1/8th mile racing that is.. I ran a best of 8.10 last year with a holley 3310, i ran last week with a new holley street hp 650 double pumper and ran 8.13 but I think i couldve gotten lower. I was hoping the double pumper would have done it. Here is my setup:

355 hyperutectic flat tops moly rings
Edelbrock performer RPM intake
062 VORTEC heads from Scoggindickey
LT4 HOT CAM (hydraulic roller .525/.525 lift)
holley 650 street hp double pumper

I haven't touched the jets in the carb yet from the plugs they look to be pretty close maybe a tad on the rich side but I always say better a little rich then a little lean. I think their might be a little more power in leaning the jets out some. I did some accelerator pump tuning that was it.

I readjusted my lifters again after last week's pass, im running 1.6 full rollers and I went 1/8 turn past zero lash. I had them a 1/4 of a turn past before im hoping this will pick up some more HP, I had them between 1/2 and 3/4 turn before and I shaved .7 off my time going to a 1/4.

Then I went to check my timing, I had it set to 35* total last year and hadn't touched it, this gave i think 12* initial, then I checked it again and still was at 12* initial but gave like ~28* total so I reset it using the same vulcan light and set it to 33-34* and it gave 16* initial now. I'm using a proform distributor. I think the light might be messed up im going to use a friends snap on light later to make sure my timing is right not sure whats going on here. I went and drove it, didn't hear any pings and plugs didn't show any signs of detonation.

Tranny is a 700r4 with shift kit and edge 3000 stall. I have 3.27 rear gears in 9-bolt and im thinking I need MORE GEAR and maybe a TH-350 trans. I can't find gears for this damn 9-bolt anywhere though. Thoughts? My buddy seems to think gears would put me in the 7.6 range.

I'm running an alternator, power steering and water pump on serpentine set up, I have 1 3/4" SLP shorty headers going to a no cat magnaflow 3" exhaust. Chevy high performance made 412hp at 5,600rpm and 428ftlbs at 5,200 with the same setup.

http://www.chevyhiperformance.com/te...ild/index.html

Of course they aren't running exhaust or accessories. I'm using the same cam but I pull more vacuum than them too, and they set their timing at 34* and then 32* using 92 octane, im using 93.

I'm running no air cleaner or pcv and I'm using 255/50-16 BFG drag radials at 16psi going around the water and doing a healthy burnout, I only got them to hookup a few times and they are starting to wear out, I think I might need some mickey thompson DRs. I shift at ~6000.

 

I might be able to get a hold of another timing light tuesday (racing on wed.). I checked might advance one with a regular timing light they both show 16* initial. Then I used a formula I found on the internet where you take 34* and divide it by 360 then times 25.137 and I got 2.37" i measured this out on masking tape and put it on my balancer. The mark was showing up at 4*ATDC so that would mean I'm still 4* retarded. I need to get another light to straighten this out. Or it could be my distributor but its new, the timing should be all in at 3000 but most of it comes in by 3500 then 2 more degrees at 4k.

 

Playing with lifter preload won't make any more HP but can cause damage as a hydraulic lifter needs a certain amount of preload to work properly. You won't change the amount of lift at the valve by changing the preload on a hydraulic lifter. Hydraulic lifters need approximately .030" preload which is very close to 1/2 turn from zero lash.

Ignition timing. Don't believe what the timing marks tell you unless you've dialed in the camshaft with a degree wheel and a piston stop. I had an adjustable timing pointer that was 8* off until I used a piston stop and a degree wheel to find the exact TDC.

If the engine makes more power, keep advancing the timing but don't be afraid about what the timing is. For all you know, 40-45* on the timing mark may make the best power even if it's not really at 40-45*.

If you don't have a balancer with degree marks on it, you can buy timing tape to wrap around it. It's easier to just use an advance timing light since then you only need to see TDC which all balancers will have.

Tires don't last forever. Even if there's still rubber on them, they can be dried out especially if they're street driven.

Gears for a 9 bolt can be found in Australia. Try www.9bolt.com

 

What damage would it cause? I've read in a lot of sources that 1/8 turn is okay, but would the proper way to do it use a dial indicator then? .030" doesnt sound like much. I had them a little more than 1/2 turn then I went to a tiny bit more then 1/4 turn and dropped about 6, 7 tenths almost, it really woke up the car. I might put them back to 1/4 if somethings going to blow up. This is a roller lifter with 1.6 full roller RAs.

So should I get a piston stop and check that the mark is at TDC or I need a degree wheel... i think its pretty close, I just installed the cam "straight up".

I need to get some mickey thompsons so I can hook up to accurately tell what improvements im making.

I guess I'll just keep advancing the timing and checking the plugs for detonation then. Do you think I should get a curve kit for the distributor?

Thhanks

 

give it some more gear and let it eat! thats the best we ran in my friend's car about 8.1x with a 10 bolt a 3.73s. always wanted to put more gear to it too

 

Using a dial indicator would be an exact measurement but there is always a tolerance so the adjustment only needs to be close. Most rocker studs give approximately 0.060" per turn.

Adjusting hydraulic lifters, flat tappet or roller.
http://www.compcams.com/Technical/FAQ/FAQLifters2.asp
http://www.popularhotrodding.com/eng...ic_lifter.html

To determine if the timing mark is correct, you need a piston stop and a degree wheel to find out when the piston is at exactly TDC. When you know the piston is at exactly TDC, the timing pointer should line up with the timing mark on the balancer. You don't really need to degree the cam but you should be making sure the timing marks are correct.

To use a piston stop that screws into the spark plug hole, the rockers for that cylinder need to be removed or the valves will hit the piston stop.

A recurve kit does 2 things. It allows you to change how much mechanical advance is in the distributor and it allows you to change how quickly the advance comes on.

Since you have a 3000 stall converter, you should be at full advance by 3000 rpm. Your base timing and mechanical timing will be your total. Sometimes if you increase the base timing to increase the total, it can be too much base timing and the engine is hard to start. You can mix and match springs and weights to get a perfect recurve but it's trial and error until you get it right. Don't just randomly install different springs or weights and think it's good. Changing the timing will change a bunch of things like jetting, plug temperature etc. When dyno tuning, the first thing that's adjusted is the timing. Changing other things such as jetting, lash (solid cam), plug gaps, plug heat ranges etc, after that won't change where the engine likes it's timing. Find out the total timing where the engine makes it's most power then don't touch the timing again unless some major adjustment has been done.

For a full race car, lock out the distributor to full advance. Cars like mine don't need an ignition curve and it's one more thing that can cause an inconsistency. My ignition system has a start retard so I can retard the ignition up to 20* to get it started then the ignition goes back to full advance when it sees more than 500 rpm. When the engine is running, it's always at full advance and never changes throughout the rpm range.

 

had bad day ran 8.3

Adjusted lifters to 1/4 turn past zero

Put in light + medium spring in distributor, called proform they said my distributor has 24* of mechanical I set base timing to 10*.


Ran down track was pinging during my burnout and launch I backed down to 8* and ran 8.3 still pinging, I backed it to 6* but didn't get to go again. I'm going to switch back to the old springs and put it at 8* and try again. Should I disconnect my vacuum advance? (street car, but for racing disconnect?)

Still couldn't get ahold of a good dial back light. I measured my balancer and its 21 5/8" circumference meaning its about a 6 7/8 balancer I think its the wrong balancer maybe, it has thet timing tab bolted to the cover like an 8" uses maybe thats the problem? Should I buy an 8" balancer?

I tried to find TDC using a screwdriver and then a big bolt in the spark plug hole but it WOULDNT STOP the piston??? vortec heads and flat tops, how come it didn't stop it?

Gotta get this timing straightened out before i can do anyhting else.

 

Vacuum advance is for part throttle operation under load. It won't normally affect WOT operation. You can easily disconnect it and plug the line when racing to remove one more variable.

Putting "one light and one medium" spring in and not checking is just guessing. You set the timing for 10*, you assume the distributor is still 24* of mechanical so that should give you 34* (with the vacuum advance disconnected). The springs change how fast the advance comes in. You need to run the engine and see what the maximum advance is and at what rpm it stops increasing. To do this you need a degreed balancer, timing tape or an adjustable timing light since factory marks won't let you see that much advance. Of course if TDC isn't accurate then what you set it for doesn't mean much.

You can't use a bolt or screwdriver to find TDC. A piston stop is an accurate mechanical stop. The head on the engine version is a special brass tool that screws into the spark plug hole. It screws in far enough that it will stop the piston from coming all the way to the top of the cylinder. As I've already mentioned, the rockers need to be removed or they'll hit the stop.

Using a degree wheel, you bar the engine over until the piston hits the stop. Using a pointer (coat hanger bolted to the engine somewhere) anywhere on the degree wheel, record the number. Bar the engine over the other way until the piston hits the stop again. Record the number on the degree wheel. Half way between the 2 numbers is TDC. Remove the piston stop and bar the engine over until the half way mark is lined up to the pointer. The piston is now exactly at TDC. The timing pointer should now be lined up with the mark on the balancer.

You can use whatever balancer you want however only the TDC mark will be accurate. If you're using a different balancer than what the factory style multi marked pointer is for then the degree marks will not be accurate. That's why an adjustable timing light is useful. All you need to know is if TDC is accurate. If you want to set the timing at 8*, you adjust the timing light to 8* and adjust the timing to the TDC mark.

It's even possible you have a completely different balancer on the engine. Most have the timing mark around the 2 o'clock position but there are some that have it close to the 12 o'clock position.

 

Maybe I need to try again and get a piston stop then perhaps balancer is way off? I adjusted all my valves using the #1 and #6 @TDC method, will they be misadjusted now? I think my balancer is close though I marked it off in 90* when I did a leakdown test and everything went fine. I'm not sure a piston stop will stop the piston though, I used a bolt that fit snugly in the spark plug hole and it should of been long enough, I also tried an extension and a screwdriver and neither worked. My buddy said they would stop the piston. Noone sells a piston stop except online Iguess I'll have to order one if you think it will stop the piston. Will it work on vortec heads and flat tops?

I asked proform about the springs because the kit I bought the center plate would not fit. They told me the distributor will always have 24* no matter what springs I use is that true? Hopefully my snap on dial back will come today.

And the thing is with the springs I had it set at 12* with the proform springs and no pinging or anything ran a 8.10 with that, and then I put in the light springs and it jumped my base to 17* without moving the dizzy, so I put a light and a medium in and they were at 12* but if you rev it it takes a while to come down and moves erratically. I put the old springs back in because of this and the pinging. Maybe I got bad gas but I used 93 from the same sunoco I always go to. Doesn't seem to run as good on the street with 8* base, with more initial it seems like I have more bottem end but less on top, hard to tell on the street though.

 

Valve adjustment should be close enough. If your balancer mark was way off, the engine would have a hard time running. You know the timing is close. You just don't know if it's exact.

Changing the distributor springs doesn't change the mechanical advance. They just change the curve or how early/late the curve is before full advance. You need to change the weights and cam in the distributor to change the mechanical advance.

 

What kinda MPH does it pull? what do you 60ft???

 

i dont know the 60 but the mph was 91

 

HELL YEAH! Thats Flyin for what you got...THats an easy 7.50 car with some hook.....My car is gonna fly as soon as I stick my Lunati 232/242 .510/.525 cam in there....

 

You need to physically limit the mechanical advance stop limit within the distributor.
You will have to tear down (disassemble) the distributor and modify the advance pin slot to limit the mech advance travel. Weld up the advance slot and regrind.
The mechanical advance travel limit is now 24deg. You want around 12 to 14.
This will allow 34 to 36 deg total max mechanical advance with 20 to 22 deg initial at idle for best throttle responce, hard launch and 1/8th mile et, without over advanced timing at high rpm.

Once the distributor mechanical advance travel is properly limited you can experiment with the advance springs.
You want to set it up so that you can launch the car clean and hard from idle or just off idle without preloading the torque converter at the start. (max converter flash stall effect.)
This is what creates the hardest "foot brake" launch, lowest 60ft and ET slip.

Vacuum advance:
Get a Crane, Mr. Gasket replacement adjustable vacuum advance and limit its travel also (vac adv stop limit plate). 10-12deg and play with the diaphram spring tension.



Fabricate your own custom built vortec piston stop tool using a vortec spark plug body and a short length of 3/8" steel tubing. Knock the center out of a old vortec style spark plug and weld the 3/8" or 5/16" steel tubing pipe into the center. Cut to length and bend the end a bit so it points down in the cylinder a bit to contact the piston top before TDC. You may have to play with the length and bend angle to get it just right, while still allowing easy install and removal in the spark plug hole.
Put a mark on your home made sparkplug/piston stop tool hex to indicate the direction of the bent tube.
You must loosen off the rockers of the #1 cylinder completely so the valves will not open while using the piston stop or the valves will interfer with the stop.
Find true TDC and move the timing pointer. 36° BTDC is 1/10th the distance around the diameter of your balancer from true TDC.



Set up the rockers adjustment hyd lifter preload while the engine is running at idle. Slow the idle rpm speed down as much as possible to minimize oil mess.
Set all rockers preload to just "0 lash" while running at slow idle. Shut the motor off and add 1/4 turn of preload to each rocker nut. Reinstall the valve covers, Restart and readjust the idle speed.
The magazine dyno tests you refer to was achived using long tube headers and open exhaust on a dyno.
Shorty headers do not make near the low end grunt (torque) that long tubes get. But...

You can maximize the low end grunt you can get with shorty headers by building a proper 2 into 1 Y pipe with a merge style scavenger Y. Flowmaster #Y250350 or # Y250300

Note the rpm point where maximum engine torque falls. For hardest launch and lowest ET you want the torque converter stall speed to be at, or just below (~500 rpm ish) the point of max engine torque output.
in this case peak torque is at 5200 rpm. For this engine, You would want a "4000stall" to "4800 stall" torque converter, for best possible launch.

Then you need raw tire traction.

Get some slicks. M/T ET Street "DOT legal slicks" work very well. (14psi)

Get some 4.10's or 4.56's and some Air-Lift rear air bags (drag bags) to maximize starting line torque , control axle torque reaction and suspension squat and maximize traction for best 60FT times and ET.

7.30's are possible without adding any Horsepower.


www.airliftcompany.com

 

F-BIRD, I dont think it'll go .30's but 40's are definitely possible with the mods you suggested....Which is some 11.80s or possible .70s with a HOT CAM!

 

Thanks for the advice Fbird! I set the timing today with my buddies brand new snap on digital dial back light and we set the timing with the original proform springs that are supposed to come in at 3500 but I reved it to 4k and set it to 30* and this gave use about 15* initial. Proform supposedly says it has 24* of mechanical in it but this time I know the light isn't wrong. I'll get a piston stop to verify TDC but im pretty sure its close. Going to see what it runs wed if it isnt rained out. I'm going to see what it does and then try modding the distributor.

Will 255/50-16 mickey thompson street drag radials be sticky enough?? The bfg DR's I have now suck. I dont want to run slicks because I drive to the track with them on.

Should I lose the 700r4 and put in a TH-350? I had edge racing custom make the stall for my app and they came up with 3000 stall because its a daily driven street car.. I can get a manual valve bodied TH350 with a 3500 stall from someone would that be too much stall for the street?

Going to try to find some gears for this crappy 9-bolt rear looks like 3.73s are the most common going to see if I can locate some 4.10s.

I wanna try and lower my times tuning the engine first before I go spending a ton of $$$$.

 

9bolt.com wants 350 bucks for a used 4.11 ring and pinon.. not gonna happen I can get some 3.70s off ebay for about 180. Is that enough to make a difference from 3.27s

 

Keep the 700...Get it re-stalled to at least 3600.....You want it stall as close to 4000 as possible....With the lock up feature of the 700, it will be PERFECTLY streetable....3.70 would a nice improvement.....AND leave you enough room to still spray it later....

 

getting it restalled would probably cost more than buying the th350 w/ a 3500 stall from my buddy.. damn edge racing should of gave me a 3600 stall to begin with! You think going to just 3.70s would wake the car up that much?

 

I doubt it.... You'll have to do the drive shaft, torque arm bracket, and/or crossmember...So cost will be about the same..Plus you'll effectively increase the starting line ratio even more...Making a gear swap even more necessary....And the gear swap, No, I dont think it'll wake "That Much"....But, it with the stall increase, it'll definitely help knock the ET down..

 

oh yeah forgot about the torque arm. I'll have to call edge and see how much itll cost. For now i think im gonna get my timing right and my distributor set up and then buy the piston stop and some M/T Drag radials and buy the 3.70s and see what it does.

 

sounds like a good start...

 

came home pissed today did 3 passes didnt have any more money for 4. First time I ran an 8.30 w/ some spin. So I advanced the timing 2 degrees, this time I spun all over the track and ran a 9.0. So I retarded the timing 2 degrees and ran 8.5. So at least I know i need to advance it so i turned it back and went home. My tires are shot im going to order the mickey thompsons tonight hopefully they come in time and hopefully they hook up at least. I'm going to order the stuff for the distributor too.


Car seems to bog down off the line, it doesnt cut out so much as it doesnt feel like it has any power until about 3500 adn then once it hits 4500 its pulls HARD and tires usually break loose. I'm thinking I still need more accelerator pump shot. I already put both cames in the 2nd position and I put a 29 squirter in back and a 32 squirter in front. They had a 29/28 before. It free revs pretty good and drives good on the street but it could use a tad more shot.. I'm thinking I should get a pump cam assortment..

Should I mess with the jetting yet or no? I have to call the track and see what I need to pass tech so I can go on test and tune day and get a real timeslip and find out my 60 and trap speed.


What I also dont get is why if my proform distributor has 24* mechanical all in at 3500 and I set the timing to 30* at 4000 and then I end up with 14* initial?? Giving me 16* mechanical I called proform and they don't know why either.

 

oh one more thing should I be brake torquing off the line or no? I hold the brakes and go about 1800 rpm and then I release brake and punch it on last yellow



------


Just called JEGS and ordered the M/T's, piston stop, adjustable vacuum can, moroso curve kit and holley pump cams.

 

Alright guys a little update:

I pulled the rockers off #1, went past TDC and put my piston stop in and screwed it in all the way, turned the engine back till it stopped and marked the balance where TDC on the tab is. Then went around until it stopped again and marked it. I marked TDC halfway between these two marks. My original mark was about an 1" off, so thats about 12* retarded. Set the base to 6*.

The moroso curve kit like the mr gasket kit has weights that don't fit. I used one proform spring and one light gold spring. I installed the adjustable vacuum advance to 12*. Took it for a spin, didn't hear any pinging and it SEEMED to pull harder.

I will mount up my M/T street DR's tommorow and get my buddies snap on light to accurately set the total timing.

I was going to put a green pump cam in but after changing the timing it doesn't seem to need it anymore.


Do you guys think I should readjust the valves again since the mark was off? I dont have a pair of old valve covers to keep the oil from pouring out.

 

Wow just took the car for a ride after setting the timing, the car is a ROCKET now... And I only timed it to 31* total, 12* initial. I might bump it up to 32* when I readjust the valves tomorrow. I got the m/t's mounted up, im planning on running them at 17-18 psi and going around the water doing a good burnout in the damp and brake torque off the line. Car feel sures like a 7 second car but only tomorrow will tell but i got my hopes up!

 

Still sorting out the timing issues but now I got another bad isssue. Wheel hop. That's why im hooking off the line and then loosing it my buddy said my rear wheels popped right off the ground! One guy said I need air shocks so it doesnt squat and another guy said i should get lakewood traction bars. Any suggestions?

 

LCARBS







look at it this way
its a $60 fix versus air bags ($200?) or traction bars ($who knows)

 

I was thinking about changing the springs because i think they have sagged, and putting the air shocks in. Aren't the LCARBS only for if you lower your car?

 

technically if the springs have sagged it has been lowered! most of the time with these cars you want the control arm running down hill to the axle. do the LCARB's and som LCA's and call me in the morning

 

Im looking at the UMI Bolt on LCARBs, should I definetly get LCA's too? How are the spohn tubular with poly bushing LCAs?

 

i've always had good luck with BMR stuff personally. but definitely some tubular ones with poly bushings and then the LCARBs the bolt ins will work but i'd still at least tack weld them in

 

Get the LCRRB's with the new tires and go to the track. No use in tunning (unless its on a dyno) untill you can get it down the track without spinning.
Have the relocation brackets welded in and start out in the lowest holes.

Then you can check you et/mph and go from there. Right now you are all over the place with et and dont know what the car is doing.

Dont "brake torque" the car. Leave just off idle and let the convert flash.

Make sure the throttle is opening all the way, and dont mess with the pump cams just yet.

You could use more gear and more converter, but just run it and see were its at for now.

 

i wouldn't just leave off idle, get on the the throttle just enough to load the drivetrain and get the slack out of everything, your rear diff will appreciate it

 

Depends on where he has the idle set. For racing, I bump mine up an extra 100rpm then load to about 1200. I have tried holding to 1800 then dumping the gas, but got better 60fts by leaving just a few hundred rpm off idle.

But yeah, these 10 bolts cant take too much shock. Usinging a auto does help over using a 5 spd.

 

I put new rear springs in the old ones were worn out. Throttle opens all the way. I'll use the suggestions.

One question, im going to order the LCARBS and I want to know before I order them If I need new LCAs or if the stock ones will be good enough for now.

 

You'll probabily find the rear air bags (Drag Bags) do more for your launch.
Corrects lower control arm geometry and pinion angle + allows right/left side axle bias adjustment+ allows adjusting the rear spring rate, eliminates wheel hop all by adding air to the bags for track use.
You can let the air out if you wish for normal street driving.
www.airliftcompany.com

Very easy to install.

 

I added Spohn LCARB's placing the stock LCA's in the bottom hole. I also added a Poly T/A mount. The wheel hop is totally gone.

This was just my results, so do as you wish.

 

alright thanks bluegrassz ill order just the LCARBS im going to get the UMI bolt on ones

 

You need to have them welded also.

 

yeah i'd save the money and get real weld ins because you need to weld them anyway. find a buddy with a welder if you don't have one yourself

 

My buddys got a welder ill get the spohn weld in ones then. Any clearance problems with PBR calipers?

 

You shouldnt have any problems. Plenty of guys running them with all sorts of brake setups.

 

brackets are on the way, ran an 8.5 still spinning the tires but not as bad, cant seem to get back to where I was.. frustrated hopefully brackets will at least make me hook and i can figure out this *#$^&*#($ timing. I think i might switch carbs to an eldebrock and see what happens. I go and check with the piston stop again and now it looks like the old mark was right maybe off a degree or 2 so I set total to 35.

 

What was your 60ft times?
Was that on the new tires?

You will be fine with the Holley. Lets get it hooking first with some solid runs.

 

I ran 8.10 last year with the 3310 carb on bifgs, I ran 8.13 with the new carb on the same tires. Then they stopped hooking up, and i put the new mickeys on and have been having wheel hop problems. The ignition timing is driving me crazy, I think im going to put everything back the way it was, timing, valve adjustment and put the accelerator pumps back to stock.

I wish I knew what the 60ft time was I go on wednesday and you can run anything you bring for 5 bucks a run, they dont give you a timeslip though. I could go on test and tune on tuesday but I'd have to fix my rubber fuel lines, battery tie down, neutral safety, get a helmet and probably some other stuff I dont know about to pass tech.

 

we really can't be any help to you without full time slips including MPH

 

Well, if you are going to do any racing, you need to get those things fixed anyway. You should be wearing a helmet also. Not trying to come off harsh.

Put the 650 hp carb back to factory specs. The stock accelerator pumps should be fine. Adjust the valves to 1/4-1/2 past zero lash. Mark your balancer and get your timing correct. Add the LCARB's and play with the air presure in the m/t's before you go back to the track.

Without a dyno or track times/mph, trying to get the carb to its best is like pissing in the wind. You can get it close for just driving, but you will not get it to or close to 100%.

 

i agree, get the car legal, take it back to the track and get some full time slips

 

I welded the LCARBs in, put the other pump cams back in, dropped the tire pressure and she hooked up. Got her down to an 8.10, it still needs more timing im going to do more tuning next week ill go on tuesday so I can get timeslips. I'm going to pull out 2 jet sizes because it looks like by the plugs its running too rich.