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Some questions during install of my new 406 SBC - street/strip/show/autoX
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Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Went to Island Dragway on Friday night for Test and Tune, along with a buddy who was running his 57 Chevy. We had a good time; early on the track needed to come around a bit with prep, but after that, things went pretty well.
Front struts are non-adjustable 90/10 Lakewood's and the rear Koni shocks I set at 3/5 drivers side and I tried 4/5 on the passenger side. Front tires were at 48 psi all night and the rear tires were between 18.0 and 18.4 psi all night long. Still suffering from the nervous jitters with the nitrous and even sometimes forgetting to hold the damn button down during the whole pass. That I hope to change, and hopefully soon! The moisture content was high all night, humidity in the 89%-91% according to my app. The DA was about 1200 at the start of the night and right about 1,000 at my last run, again according to my app, which is less reputable than most.
-on all nitrous passes I had the nitrous set to come on at 3,000 rpms. I might lower this to come on directly when I do launch because its almost feeling like I have a "double launch" sensation.
- I use the same timing numbers for my 100 and 125 nitrous shots, so I actually use the same tune file. so even though it says F125 on the page, I use that same file for a fixed 100 shot.. same goes for the progressive shots. I am pulling 4.5 degrees of timing for both a 125 and 100 shot. So it is at 29.5 deg on nitrous, and 34 deg on motor.
Pass 1:
All motor, no nitrous. Did a very short burnout because I forgot to pump the brakes hard before activating the line lock, so about 1 second into the burnout it pushed through the brakes and darted me forward. The track starter motioned that I could do another one (and I should have) but I told him no and staged. Foot brake launch at 1475 rpms and it instantly spun. Pedaled it, short shifted 1-2 at 5400 rpms, and then short shifted 2-3 shift at 5,421 rpms, crossed the line at 6177 rpms like a total goofball and it ran 12.23 at 113. The top green line is my Throttle position sensor, so you can see I was not at full throttle most of 1st gear and all of 2nd gear.
Pass 2:
Hoping to redeem myself from the above nonsense, I decided to do a progressive-ramp 100 shot. After a proper 7 second burnout, I footbraked the launch at 1580 rpms and then the ramp came in at 3,000 rpms. The 1.52 sixty foot felt real good! The green line in the datalog thats across the middle of the page, you can see the timing ramp before it goes flat. When it is flat I am on the nitrous, when the line goes upwards and then flat and then downwards, those are moments I am off the nitrous. As you cans ee I was off the nitrous between the 1-2 shift, the 2-3 shift and again (twice) at the top of third gear. Anyways, I shifted 1-2 at 6,700 rpms, 2-3 at 6,230 rpms, and crossed the finish line at 6515 (of the nitrous). Same as last TnT event, I am out of rpms at the top of 3rd gear (more info on that later), but thats why you hear the engine "lay over" about 200 feet from the finish line.
Pass 3:
Changed from a progressive 100 shot to a fixed 100 shot. Did a 6 second burnout and footbraked the launch from 2,002 rpms. Shifted 1-2 at 6,706 rpms, 2-3 at 6,417 rpms, and across the line at 6,536 rpms. Again, not on the nitrous with 200 feet left before the finish line.. out of rpms. I was on the button the whole time and the only time the nitrous turned off is when it hit the "high rpm limit" at the top of 1st gear and also at the top of 3rd gear. I did notice (and can be seen in the log also) that I had less footage between where I was and the finish line when the nitrous went off at the top of third. food for thought!
Pass 4:
I decided I was ready to change from a 100 shot to a 125 shot, so I did. Did a 7 second burnout and footbrake launched from 1693 rpms. Shifted 1-2 at 6,782 and 2-3 at 6486 rpms which put me crossing the line at 6477 rpms. I know the nitrous clicked off at the top of first gear, and it appears that I got off the button while shifting from 2-3..and didn't get back on the button for over 2 seconds.. .until I was mid way through 3rd gear! ugh, you can hear it in the video too.
Pass 5:
Switched lanes. Still a fixed 125 shot coming on at 3,000 rpms. 6 second burnout. Footbrake launch from 1421 rpms. Kinda wish I was at least caring somewhat abotu reaction time, because this would have been a good side-by-side pass against that Malibu. But, like my TnT session 2 weeks ago, I was way more focused on leaving at the proper rpm instead of drilling the perfect .000 reaction time. Anyways, it went 1.47 to the 60 foot and It was spinning a bit but I staked in it and it came out of it. You can see the hood shake as the tires shatter a bit. Still, was happy with the launch, and then 1-2 shift at 6,757 2-3 shift 6492, and finish line 6606 rpms. That slight "flat spot" in the red data-trace is when the tires grabbed through the spin in 1st gear. That run pumped me up, and I was justtt starting to reel him in at the top end.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Pass 6:
8 second burnout, footbrake launch at 2019 1-2 shift at 6740, 2-3 shift at 6503, 3-4 shift 6012, and finish line 5438. You read that right, a 3-4 shift . I was not sure how it was going to go, and maybe it will be better, but I shifted 3-4 wayyy to early so it was a doggg in 4th gear which is a dog anyway in 700r4 transmissions.. even on nitrous. ODDLY, the mph was the same as my other passes where I was topping out at 3rd gear. ??!?!
Pass 7:
6.5 second burnout, and a 1666 rpms footbrake launch. Using another view/page of the datalog (not pictured here) I see what went wrong on this run. One of my safeties (nitrous rich cut-off limit) was activated just a second into 1st gear, so the ecu shut off the nitrous. So my launch was good, but then it was an all-motor pass the rest of the way. Shifter 1-2 at 6523, shifted 2-3 6223, and finish line at 6249. I do physically remember shifting 3-4 during this run too, but for some reason the transmission did not make the shift. Kinda weird, but will have to look into this. It did it the previous run, but maybe it was hot or just damn tired?
Some other videos that were filmed by a drag race friend named Tom who runs at Island . Jerry also took some videos, but I feel super badly that I did not get to film any of his runs.
-note.. I do not know which pass each launch video is from, so I am sorry, I only know the one against that Malibu was pass #5.
Drove the car home late at night. Washed it the next morning and swapped the wheels. Took it to the North Jersey Auto Show today (Sunday) in Paramus. it was raining from the moment I left, and most of the morning. They had a smaller turnout than the usual 400 cars that they get at this show, and I was in the 1980-present class. (they only allow vehicles up to 1996, so I guess the way tos ay it is I was in the 1980-1996 class). Got the class trophy, and drove home in the rain.. with the lakewood 90/10 drag struts, no front sway bar, and maniacs on rt 8p in north jersey.
Going to look into the trans 3-4 shifting situation. My best bet about how to rev out the engine during the last 200 feet of the track is a taller set of tires.. this will have to waif for spring 2022. If anyone has a set of 15" drag wheels with a 27" or 28" tire that I could test fit for a size mockup, please let me know. It would be much appreciated.
On that note, after watching some of Jerry's videos and Tom's videos, I now know that the car does squat. In fact, I was certain that I felt the rear bump-stops hit the axle tube on at least two launches. I mentioned this to the fellas, and I ended up cranking up each reach shock .5 It was probably not enough. I have done a bunch of research and have some 3rd gen buddies who have used the drag-bag air-bags before. It is a budget friendly trick I would like to try so I am probably going to order a set of these. They will also help when I haul the hundreds of pounds of tools to and from each event too. Especially with a taller tire...
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Do all the Fun-Driving in D3, D2, or D1 ONLY.
D4/ OD with the THM700-R4 is just for light throttle expressway driving.
The Overrun Clutch does not support the Sprag assembly in 4th-Gear and can cause issues very easily.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by IROCZman15
On that note, after watching some of Jerry's videos and Tom's videos, I now know that the car does squat. In fact, I was certain that I felt the rear bump-stops hit the axle tube on at least two launches. I mentioned this to the fellas, and I ended up cranking up each reach shock .5 It was probably not enough. I have done a bunch of research and have some 3rd gen buddies who have used the drag-bag air-bags before. It is a budget friendly trick I would like to try so I am probably going to order a set of these. They will also help when I haul the hundreds of pounds of tools to and from each event too. Especially with a taller tire...
As I mentioned, those are fitted to my Camaro. Not only can you bias the suspension left to right but with inflation not only do you get an increased resistance to forces generated at the hit but also a slight increase in rear ride height. This is turns improves the lower control angle for even less squatting.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
QwkTrip and vorteciroc: Ok, this is good to know. I really never had looked into doing the 3-4 shift beforehand, and I am kicking myself for not doing research prior to it. I saw your reply a few hours earlier and sent an email about the topic to Dana at ProBuilt Automatics who built the trans, but I know you guys know your tech stuff, so I am damn sure going to avoid shifting 3-4 anytime ever again at a drag race. Good to know.
Someone (not on here) suggested using my torque converter lockup switch to lock up the converter at the very top of 3rd gear so it could pull the rpms down another 300 or so, and then ride them up to the finish line. I do have my doubts on this, because of the small size and strength of the TCC lockup clutch itself. Even in a built 9.5" Edge Racing 3400 converter with anti-balloon plate, I have my doubts about the TCC clutch holding up to that. Should I cross that off as an option? I obviously do NOT want to explode a converter by locking up the converter at WOT in 3rd gear on the spray!
Skinny: Just ordered the Air Lift 60897 air bags, and also bought a bottle of that Geddex Burnout guard spray. I have tried waxing the rear fenders to keep burnout rubber away, but cleanup hasn't gone as well as I would like. Several people have recommended the Geddex spray, so I am willing to try it for $10.The benefits of the air bags that you mention sound awesome. Another benefit, is that when I load the hundreds of pounds of tools and gear into my car for each drag race or autocross event, I can use the air bags to help keep the inner wheel tubs from scuffing the tires when i hit a hard bump in the road. Very cool. It has been suggested to me to only run about 5-8 pounds in the bags while getting everything dialed in.
It seems no matter what I do, the car just wont get a wheel (or two) airborn. I know it is not optimal, but I'm craving a wheelie photo to put up in the garage. Even with the 1.47 and 1.48 sixty foot launches, it just wont get air! Bah! Maybe the air-bags, along with bringing in the nitrous exactly at the launch hit (instead of at 3,000 rpms) in 1st gear will do it.
Last edited by IROCZman15; 10-11-2021 at 08:23 PM.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Single Friction Element Torque-Converters are not intended for Lock-Up operation under a Load.
Only light throttle cruising (Triple Element Units are available for 2nd-Gear and 3rd Gear Lock-Up under heavy throttle).
Reaching out to Dana for help or clarification is never a bad idea for your PBA built Transmission.
Dana is up to date on everything new for THM700-R4 Transmissions.
He always wants to know about and offer the best of the best for his Transmissions.
He will always reach-out to me if he ever has a question on a Build, or regarding new designs/ parts.
I very highly recommend Him... most Transmission Builders do not keep in touch with an Engineer to better their Transmissions.
I can not say enough about him!
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by vorteciroc
... ever has a question on a Build, or regarding new designs/ parts.
I'll reach out here with a little off topic question.
What's your take on GMs 5 pinion planetaries as a late model parts upgrade in an old school 700R4?
We did just that on a couple of our own level 3.5 rebuilds.
The planetaries are genuine GM parts just for the record.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by skinny z
I'll reach out here with a little off topic question.
What's your take on GMs 5 pinion planetaries as a late model parts upgrade in an old school 700R4?
We did just that on a couple of our own level 3.5 rebuilds.
The planetaries are genuine GM parts just for the record.
I was still with GM when these Parts were designed, and then put into production.
There are not an upgrade.
They are a cost savings measure.
I will refer to a previous Post I made on LS1Tech.com:
Originally Posted by vorteciroc
Regarding the Planetary gears:
-From a load distribution standpoint; if two planetary gears are being compared, with the only difference being the number of pinion gears (metallurgy, dimensions, and everything else is identical)...
then the planet with 5 pinion gears would be better at spreading/ distributing the load/ force placed upon it and be considered stronger.
-However the "4L60E family" 5 pinion planets are made of inferior metallurgy, and are over all weaker than the 4 pinion planets.
To try and compensate for the inferior metallurgy; we increased the mass/ material surrounding the pinion gears... However it was simply not enough.
Look at this image of a 4 pinion planet. Notice the space/ air/ open area around the pinion gears:
This is a good thing, as it better allows lubrication oil to move/ spread about.
Compare that to this image of a 5 pinion planet:
The open area (around the pinion gear) had to be reduced to try and bring back some strength over all to the planet.
This however slightly hurts the lubrication.
On the rear 5 pinion planetary gear; we were able to add some lube oil slots to slightly improve the lube to the pinion gears.
You will see the OEM 5 pinion planets crack/ break way before the 4 pinion models.
The aftermarket 5 pinion planets are even worse... Do NOT ever purchase these.
There was absolutely nothing wrong with the 4 pinion planets... the only reason we actually made the 5 pinion gears was to save money (these parts were a cost cutting measure).
If everything else were identical... 5 pinion gears would be stronger.
But as I explained, the metallurgy/ casting is weaker... thus the planet as a whole is weaker.
You can use the 5 pinion planets... just not with high power.
I would switch to the 4 pinion planets in the 500 HP+ range... or if you have 4 pinion planets, just keep them.
The 4 pinion sets have survived over a year at 1,200+ rear wheel HP in one of my test vehicles... i can NOT say the same for the 5 pinion sets (I have broken the castings at less than half that power).
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
This is the wrong place for this...
But the Auto. Trans. Forum on LS1Tech.com, is filled with a ton more information on the THM700-R4 and 4L60E.
I am much more active there, than anywhere else.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
True enough. Not my thread but I know IROCZman appreciates good tech.
That said, those transmissions have long since been built and are in service.
I guess time will tell.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
heck yea, have at it fellas. Feel free to discuss any tech stuff on here; it can only help me and others, and that is what this forum is for!
As a matter of fact, about 4 years ago when I was having the transmission built by Dana (and builder Mike) I was told by Dana that he would be using the stronger 4 pinion planetary. He assured me it was the best choice for my application and I told him it sure sounded like it. I can attest that Dana and Mike at Pb transmissions did a super awesome job with my 700R as it has held up absolutely awesome over these past few years of some serious use. I'm still not well versed in the engineering and tech of a transmission, but I know who to reach out to if I have questions!
Thanks for the info vortech. I was skeptical about activating the lockup on the converter too. Glad to know that is should not be done. I know sometimes Dana takes a few days to get to his emails, so I don't expect to hear back from him right away. I can always call him this weekend too, but I am sure he will give the same kind of answers that you have here.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Something that I really like about Dana (PBA) is that when he does not know something...
He is not afraid to ask (and that only makes him better at serving his customers).
He will call me up when he needs to know about something...
He will call TransGo, Sonnax, Etc.
5-Pinion Planetary Gear-Sets are olds news now, but people who sell Transmission Parts...
often (unintelligently) still hype them up (like they are the latest greatest thing for your Transmission).
I told Dana, a long time ago... NO 5-Pinion Planets!
(especially aftermarket versions that are bigger pieces of Crap).
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
WOW!
That is quite the collection of Absurd Blower Configurations!
I love it!
If the Blower in my Post did not already produce 10,000 HP (the reason I am no longer permitted to use it)...
I would try one of those crazy configurations (not that I would be permitted to use them either).
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
ah, that orange/gold GTO There was a picture of a girl in cowboy-boots sitting on top of the dual-stacked blowers of that GTO that was my computer's desktop wallpaper for a long-long time, back about 10-12 years ago. What a car!
If that blower is free, I WILL TAKE IT and I will pay shipping. Would make some very cool garage wall art for a while!
got air-bags installed. Probably wont get to the track for another week or two though. So I'll just do some mild street hits.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
It weights about 160 - 170 Lbs... you could reinforce the wall.
It would be cheaper if you want to take a drive to Manhattan; rather than shipping it.
I will sell it for scrap value... (waiting to hear what it will be worth).
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Wow, I honestly didn't think you were serious about selling it. I am intrigued to say the least. I know for sure it would never find its way onto a project of mine, but it would be an awesome awesome piece of garage art.
If you are indeed serious, and would let it go for scrap value, feel free to send me a PM. I'm over in new jersey, and if the price is right, it might be worth the adventure.
So, Send me a PM if you get a price number.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by IROCZman15
.... It has been suggested to me to only run about 5-8 pounds in the bags while getting everything dialed in.
IIRC, AirLift says 4 PSI as a minimum working pressure.
At one point I believe I was 20 PSI right side and 10-15 on the left.
There IS a noticeable on my Camaro with respect to how much the back ends drops. Or how little I suppose.
I'll have to go through my notes for a timeline on first using them and 60' times.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by IROCZman15
Wow, I honestly didn't think you were serious about selling it. I am intrigued to say the least. I know for sure it would never find its way onto a project of mine, but it would be an awesome awesome piece of garage art.
If you are indeed serious, and would let it go for scrap value, feel free to send me a PM. I'm over in new jersey, and if the price is right, it might be worth the adventure.
So, Send me a PM if you get a price number.
Yeah, why not.
Have you looked into obtaining your Sportsman NHRA Competition License?
Would you be interested in learning to drive a faster car... and possibly earn the corresponding license?
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
air bags have been great on the street, In fact, I don't notice that they are there. just 8 psi in each for now. Did a few car shows this weekend and put a total of 96 miles on the car. Hoping to get to the dragstrip this upcoming weekend to see how the bags may help with launch/squat.
vortech, well, I mean, I can't claim to have much racing experience aside from driving my own car. However, the performance car territory is what I hope to be involved in for a career and a hobby for the remainder of my life. One day I will hope to have a faster car which is a dedicated drag car. The budget won't be there for this for quite some time, but I am ok with that for now since I have a fun street car and can keep improving myself and the car in the coming years.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by skinny z
I'll reach out here with a little off topic question.
What's your take on GMs 5 pinion planetaries as a late model parts upgrade in an old school 700R4?
We did just that on a couple of our own level 3.5 rebuilds.
The planetaries are genuine GM parts just for the record.
The big if. Alot of fakes floating around with subpar metal. My builder who unfortunately passed away 2 years ago is dead set in using the 4 pinions. Less rotating mass, just as strong if not stronger was the response. He built alot of 4l60e into the deep 9s in 4500lb impala. His buisness is still running out of Maryland. Cahall performance trans. The biggest deciding factor imo is the guy who assembles it. Its all in the small details.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
That is a wild concept for me to imagine Vortec! I have always had dreams to go fast and be good at it, but the thought of (eventually) piloting a funny car is astonishing and wild. I gotta say that I consider myself pretty unskilled on aspects like reaction time, engine dynamics, and the hustle of grudge/bracket racing, but there will always be a desire for me to go faster and get better. This year and last year were really the only "fast" drag racing stuff I have done; aside from that, I was just used to 14 second passes in this car, and I made a few 13 second passes in my brother's 93 trans am.
IROCZ1989 - my brother had Cahill Performance Transmissions build his 4l60 and it eventually ran high 12s but that trans and the vigilatne converter were well built and he never had any issues. This was in the mid 2000's .
so far, the air bags are not-noticeable for the street, but I really haven't tried to launch from a dead stop on the streets. Just stuff from a roll and normal hard-street driving, but I can't tell much yet. Next time I get to the track, that will be the true test. The one thing I do know (and have to remedy) is that the bags have lifted the back-end of the car body exactly 9/16" on each side. I have 8 psi in the drivers side bag and 10 psi in the pass side airbag. From what I can tell, this is because of the poly-isolator piece and how it sits on the lower spring perch of the moser 12 bolt axle housing. I have a plan to fix this, but it will have to wait until winter when the car is off the road and bigger projects will take place. The benefit of it now though, is that I am pretty sure I can easily fit a taller tire, which will help my 3rd gear redline issue as I approach the finish line.
Last edited by IROCZman15; 10-20-2021 at 08:24 PM.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by IROCZman15
The benefit of it now though, is that I am pretty sure I can easily fit a taller tire, which will help my 3rd gear redline issue as I approach the finish line.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by IROCZman15
The one thing I do know (and have to remedy) is that the bags have lifted the back-end of the car body exactly 9/16" on each side. I have 8 psi in the drivers side bag and 10 psi in the pass side airbag.
Try dropping the pressures to the 4 PSI minimum for street driving. I think you'll find that there's very little impact to ride height then.
Then, at the track don't be afraid to go to 20+ PSI to get results. Especially if your car is a low as mine. It can have a profound effect on the drive lines angles (in particular the LCA angle).
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Had planned on going to Island today for TnT. For the past few weeks, November 7th was listed as an Open Test n Tune event, but just this past week it was changed to a Diesel Truck event and no cars were allowed. Kinda a bummer, but I did call and check with them that next weekend they will be open for Test and Tune as well as the "grocery getter 15.00 and slower" event. So as long as the weather holds for next weekend, November 14, I plan on going. It might be the last 1/4 mile event of the year for me, unless I decide to try to make it down to Atco.
Anyways, I decided to take the camaro out for a cruise up to my buddies house in newton today. Was stunned when out of nowhere a large male deer ran into the road, jumped onto the roof of the car in front of me, jumped off the roof, and took off ! Jeez, I am super glad that it didn't happen 5 seconds later, or I would have been the victim!
Car show season is over, nothing else local. I'll still cruise around till mid December on favorable days, before I take the car off the road for the year. Despite having the car at the chassis shop for the roll-bar install for the whole month of June, the camaro racked up More miles than my primary daily driver (2005 dodge ram) this year, and I am kinda stoked about that! It helps that I only work 0.7 miles away form home and typically drive my old 1995 jeep wrangler anyways. I've definitely enjoyed all the seat time and spent a small fortune on 93 octane shell gasoline.
So, for next weekend, I am probably going to get a bit more aggressive with the nitrous shot. My top-end MPH might still stay the same since I am topping out in 3rd gear, but I am hoping I can get a quicker 60foot, 8th and 1/4 mile e.t. by launching with a 100shot and then ramping it to a 150 shot. I'm hoping the track prep/surface will hold the launch too, and that I can improve the 1.47 sixty foot a little bit. A wheelie would be awesome for a photograph, but this car just doesn't want to lift the nose off the ground still. I still have yet to test out these new air drag-bags at the track. I'd also like to see 100 mph at the 8th mile, and my current best is 99.77 mph. can't think of much else yet; just hope the weather is good for next Sunday
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Going to start prepping the car after work this week for the TnT event this Sunday at Island. Swap wheels, remove front passenger seat, bolt check, pack tools, etc. I am also debating on removing the exhaust pipes/muffler that are after the y-pipe. I did this last year once, but I personally wasn't as dialed in with shift points so I really don't know if it helped or not. I also was not spraying nitrous last year either, but I certainly will be on Sunday.
I would keep the 1.75" Dyno Dons shorty/mid length headers on, along with the DynoDons 2.5-to-3" y-pipe. At the end of the Y-pipe I would bolt on a short 90degree turn down so the exhaust isn't blasting into the underside of the car. Same as last year.
-Therefore I would be removing the remainder of the 3" main exhaust pipe, the electric cut out, the 3" over the axle pipe, the muffler, and the two 2.5" tailpipes. When i did this last year it was certainly worth some weight savings, but I want to see if I run a better mph by having it off or not. This will help me make scientific decisions about my upcoming winter exhaust system project.
Thoughts?
I don't mind the 20 minutes of work it takes to remove the exhaust, it comes apart pretty easily...but getting it back on is a bit of a pain. Come January, a different exhaust system altogether will be getting built, so this might be the last on-off for this 3" system and maybe even the dyno dons headers/y-pipe too.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by IROCZman15
Going to start prepping the car after work this week for the TnT event this Sunday at Island. Swap wheels, remove front passenger seat, bolt check, pack tools, etc. I am also debating on removing the exhaust pipes/muffler that are after the y-pipe. I did this last year once, but I personally wasn't as dialed in with shift points so I really don't know if it helped or not. I also was not spraying nitrous last year either, but I certainly will be on Sunday.
I would keep the 1.75" Dyno Dons shorty/mid length headers on, along with the DynoDons 2.5-to-3" y-pipe. At the end of the Y-pipe I would bolt on a short 90degree turn down so the exhaust isn't blasting into the underside of the car. Same as last year.
-Therefore I would be removing the remainder of the 3" main exhaust pipe, the electric cut out, the 3" over the axle pipe, the muffler, and the two 2.5" tailpipes. When i did this last year it was certainly worth some weight savings, but I want to see if I run a better mph by having it off or not. This will help me make scientific decisions about my upcoming winter exhaust system project.
Thoughts?
I don't mind the 20 minutes of work it takes to remove the exhaust, it comes apart pretty easily...but getting it back on is a bit of a pain. Come January, a different exhaust system altogether will be getting built, so this might be the last on-off for this 3" system and maybe even the dyno dons headers/y-pipe too.
Weight savings aside you may well find yourself producing a side effect that may limit performance rather than enhance it.
As has been discussed before, if the distance from the end of the y-pipe extension to the end of the primaries is such that the reflected wave produced arrives at the exhaust at the wrong time it could well trim off several ft./lbs. of torque.
Here's where PipeMax would be helpful.
Check out these screenshots posted previously and look at the best vs worst tuned collector lengths and how suitable differences can swing the results one way or another.
(NOTE: This is an example only as the engine tested isn't a 400 CID SBC)
It continues to surprise me that with the information available today that some guys run with open headers and no tuned extension thinking that this will make more power. Most always the case there is tremendously reduced torque and the vehicle falls flat through the lower rev ranges.
Have you run any of your specs through PipeMax or similar before? I don't recall.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
very interesting skinny. I p;planned on diving into he exhaust tech. with both feet this upcoming winter. I really want to understand the science behind it, prior to spec'ing out my winter exhaust project. However, for this upcoming TnT event (and probably the last drag racing event of the year for me), I just wanted to "try it out" and run without the 55 pounds of extra exhaust. I still have the y-pipe and about 4 feet of the 3" main pipe, so its not an open-header setup. Also, the small "bullet shaped cat" is fully hollow, to its just an empty pipe basically. My existing exhaust is by far the nastiest thing on the car, and I cant wait for it to go away. I put that small 3" turndown on. Also, keep in mind that I had been running a fully-open electric exhaust cut-out just about 1 foot rearward from where I removed the existing exhaust. So, I doubt the flow/pressure will have changed at all, but I did weigh the pipes/muffler/cut-out/tips and it was right in the neighborhood of 55 pounds.
.
Anyways, I will certainly be looking for some helpful advice this winter as I spec out and build a revised exhaust for this car.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
I had mentioned here that I was looking for a Funny Driver...
I am going to part-out the Funny Car, and change over to a Dragster.
Anyone have, or want to earn a NHRA Professional-Sportsman Level 2A License... instead of the 2B License?
Top Alcohol Dragsters can run a Blown Injected Alcohol Hemi, like I have in my Funny Car...
or they can run a Normally-Aspirated Injected Nitro-Methane Hemi.
Similar to the Image below:
Top Alcohol Funny Cars are not permitted to use the Nitro-Engine.
These Engine look similar to the Image below:
Both Engine types make 5,000 to 6,000 HP.
But the Blown Alcohol Engine launches at about 7,000 RPM...
and makes Peak HP at about 11,000 RPM.
The Normally-Aspirated Nitro-Methane Engine launches from an Idle of 1,500 - 2,000 RPM...
and makes Peak HP at about 6,000 RPM.
If any of you are interested in Nitro-Methane...
It will approximately TRIPLE the output of an Engine compared to Gasoline.
Also if I tried to run my Blown Alcohol Engine on Nitro-Methane...
It would produce even more Power than the fastest NHRA Top Fuel Dragsters and Funny Cars.
The Blown Alcohol Engines have a TON more Camshaft, more Compression, and a way better Super-Charger that makes more Boost.
Last edited by vorteciroc; 11-13-2021 at 08:23 PM.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by skinny z
And collector by definition can be any length. Or could be unless otherwise limited by the rules.
As for zoomies, that's Funny Car talk...
The Rules will dictate which Model Headers are permitted for your Engine and Vehicle combination.
The Headers may not be modified...
and extensions may not be added to the Headers.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
That is some WILD WILD stuff there vortech! Monster power. Way out of my league, and I can only imagine what it would be liek to be behind the wheel of somethign that powerful!
I went to Island Dragway this past Sunday, November 14, 2021 for my final drag race TnT of this year. It was also the Daily-Driver Grocery-Getter e3vent, an Impala club event, regular Test-n-Tune, and a racing for Santa's type Toys-for-Tots fundraiser. They opened an hour earlier than usual (9am gates 10 am racing) but due to water seeping up into the track on the top-end, it took them till almost 11:30 to get the first pair of cars off. There was an insane amount of cars there. Good for business, but really a lot of down time. Lots of oil downs and whatnot too, so the track and starting line was cold temperature which made for some tricky launch conditions. Someone hit the timing system very early on, and that caused a delay too. There was a weird issue with the tree during my 1st run, as it put on the bottom bulbs before ever lighting the top bulbs (no I was not deep staged). Also, later on, someone started a fire in one of the trash barrels so they had to have the fire department come and handle everything. It was just a very long drawn out day, and they only allowed everyone to get 3 passes, unless you were in one of the bracket racing groups. My buddy John was there with his low 11 second Trans Am, and Jerry was there with his 2nd gen too! Jerry was consistent as always and I think it was the first time I got to see his bird on the track. My buddy John was lined up next to me in the left lane for our 2nd pass, and he dialed up his clutch adjustment too far and it caused him to stall on the line. This was a super big blessing in disguise because when he opened the hood to adjust the clutch valve, he noticed some milkshake colored oil/fluid in the clear hoses that connect his valve cover to his vacuum pump. He had known a head gasket was just starting to leak coolant outside the engine, but it must have just started leaking into the engine during his first pass. If he had not stalled on the line and had made the pass next to me with a blown head gasket, who knows how bad the situation could have been.
Look at how far back the line stretched!
Anyways. the drag bags seemed to work great. I did not hit the bump stops and from what it felt like in the driver's seat, the car did not squat all that much. I ran 8psi in the driver's side bag, and 10.4 psi in the passenger side bag all day. Front tires were 50 psi and the rear tires I kept at 18.5 psi all day. Had the rear shocks set at 3.5/5 driver's side and 4/5 on the passenger side. I put in the 150 jets and had a full nitrous bottle which I used the bottle heater to keep it at a steady 1,000 psi. I programmed the nitrous to only spray between 2400-6500 rpms. Weather was cold, but not all that windy. It was a negative200 - negative 300 all day, which was great, but the track temp was just dead cold because of the lack of cars being able to continually make passes amongst the very frequent down-time. Look at the clock/time differences on my timeslips, its 3 hours between pass 1and2, and 1.5 hours between pass 2and3.
Pass 1:
Did a 5.5 second burnout. Wanted to try launching from a slightly high idle, so I launched at 1036 rpms. The nitrous was programmed to come on at 2400 rpms, and I had it set up for a slow progressive ramp.. it was a 2 second long ramp from 75hp-150hp. The car sipped the tire a touch on the n/a footbrake launch and then held the tire during the nitrous ramp. Nitrous clicked off at the high-rpm limit of both shifts (as well as the top of 3rd gear still 150+ feet from the finish line). I shifted 1-2 at 6546 and 2-3 shift at 65401 rpms, and crossed the line at 6524 rpms. The car is very unhappy during the last few hundred feet, and I know I am not accelerating, I am either staying steady speed or possibly decelerating.
Video:
- I have no in car video from this pass as my memory car footage loop records, and the time at the track was sooo incredibly long, that the loop recording wrote-over my first pass.. which just so happened to be my quickest pass to date!
Fortunately, Joey D was in the stands spectating and he took a video, so here is the link to it:
Pass 2:
I was glad that the progressive 150 shot worked, and had a choice to make. Do I shorten up the progressive's ramp, or do I go out there and see if it will take a fixed 150 shot instead. Hearing the track's announcement that all cars would only get 3 runs total, I thought, well, lets put the fixed 150 shot in it and see if it takes it. My buddy John was next to me and I had hoped he was going to get his 10.99 n/a timeslip (He has been 11.02, and that is a stick shift car). I did a 5.5 second burnout, but for some reason it felt like only 1 tire was getting worked, and it has done this before, but only rarely. Foot brake launched from 1089 rpms and it barely rolled out at all before hitting 2400 rpms and getting on the nitrous, which caused it to completely knock the tires loose. So I pedaled it, got back in it and on the nitrous and tagged the rev limiter a bit before making the 1-2 shift at 6586 rpms. Second gear held fine but I was on the limiter again a bit before shifting 2-3 at 6681 rpms. I crossed the stripe while still spraying at 6614 rpms, which is weird because it should have clicked off at 6500 rpms. Was bummed out for John who I was expecting to make a side-by-side pass with me and both of us get a 10 second timeslip together.
Pass 3:
Put a progressive nitrous tune in it, but shortened the ramp to be 1.2 seconds. So it sprays from 75shot-to-150 shot in 1.2 seconds. 7 second burnout, both tires. Tried to launch from a higher rpm footbrake like I am used to doing, and I footbrake launched at 1701 rpms. I did feel the tire slip just a little bit at the hit, BUT it turns out I did not got WOT right away either, so the even though I passed my 2400 rpm On for the nitrous, it did not click on until I went past 80% TPS. This can be seen in the datalog traces below, but at the time, I did not even realize it later until I looked at the datalog. The progressive ramp was fine. And after a touch of the rev limiter I shifted 1-2 at 6652 rpms, shifted 2-3 at 6588 rpms and as usual, as I approached the finish line it clicked the nitrous off, kept my timing retard in it, and dropped rpms, which eventually had me cross the line at 6458 rpms. You can see that it did this for about 1.3 seconds on the datalog (top right corner) and hear it in the video.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
I'll type up a longer post about winter upgrades and projects in the upcoming weeks, but
My buddy John who was in the left lane next to me for my second pass at Island two weeks ago had his dash cam rolling. Since his clutch had issues and he stalled on the line, his in car video shows the beginning of my pass. It is not of great quality, but when I watched it in super slow motion, I was curious about what I saw...
...This pass was where I went to the non-progressive 150 nitrous shot coming in at 2400 rpms, so almost out of the hole. It zipped the tires loose and I got off the throttle and nitrous for an instant, and then got back on the throttle . You can see this in the previously posted (above) datalog for pass #2 and hear/see the car get loose in the pass 2 youtube video of my in-car footage. But what it looks like from his footage, is that when I got back on the throttle, it might have just slightly yanked the front driver's side wheel up an inch in the air?!?!?!? Part of me thinks its an optical illusion, but I do remember that pass and how it boogied when I got back on the throttle after peddling it. So, I wonder if this can calm my brain about thinking this car will never lift a tire. Maybe it will, maybe this time it did get a wheel up, and I didn't realize it until freeze-framing his video. Interesting.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
The Images do make it hard to tell.
I can say that I am happy to see that Car running down the Track!
I normally instruct people to not nail-the-Throttle when getting back on the Accelerator.
The Nitrous System can Kick-the-Rods and make a nice Window in your Cylinder-Block.
I know that you do not use a Large Hit...
But that is the scenario when a Window often happens...
Especially if the RPM is below peak Torque.
I know I also cautioned you about initiating the Nitrous at lower RPMs...
So just keep all that in mind.
I like to install a Selectable-Switch that provides multiple methods of Nitrous activation.
For a Non-Progressive Hit...
I will have a Momentary-Button after a Throttle-Body/ Carb. Micro-Switch.
After the Micro-Switch is active (from WOT) the Momentary-Button has to be held for the Hit to spray.
That way you can get back on the Throttle (WOT) without the Nitrous immediately coming back on (till you hold the Button).
My fingers are crossed that you keep your Connecting-Rods for a while longer!
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by vorteciroc
I like to install a Selectable-Switch that provides multiple methods of Nitrous activation.
For a Non-Progressive Hit...
I will have a Momentary-Button after a Throttle-Body/ Carb. Micro-Switch.
After the Micro-Switch is active (from WOT) the Momentary-Button has to be held for the Hit to spray.
That way you can get back on the Throttle (WOT) without the Nitrous immediately coming back on (till you hold the Button).
I follow what you are saying, but if he never let go of the button, then when he hit WOT again the nitrous would spray, correct?
I think you are trying to describe a one-shot - can be done with a relay.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Originally Posted by NoEmissions84TA
I follow what you are saying, but if he never let go of the button, then when he hit WOT again the nitrous would spray, correct?
I think you are trying to describe a one-shot - can be done with a relay.
No, not the way that I construct the Circuit.
There is an Order of Operations that must be followed for safety reasons.
The WOT Micro-Switch must be closed before the Activation Button for the System to Spray.
Re: Some questions during install of my new 406 SBC - street/strip/show/autoX
Hmmm....sure looks like it pulled that front tire.
So let a non-racer ask a question here...if that tire pull is the result of a harder launch the 2nd time compared to the initial launch....does that mean you need more converter?
09-29-2021, 07:14 PM
