(Just happened to be hanging out at my PC when...)
Front mounting point higher than the back is, from what I understand, the attitude we're trying to achieve.
Why it might be suggested it would different from one tire type to another is something I can't comment on. As far as I am aware, it's always front up for these cars.
Naturally, YMMV.

 

Took the car to Island Dragway for the annual track rental on 10/24/25. I had a few goals in mind for the day, but also had to run around a bunch making sure the event was going good since I was hosting and organizing it. One of my goals was to get at least 10 passes on the day.

I also wanted to see if I could get the Hoosiers to get me a new all-motor pb in the 1/4 mile and possibly a good 1/8th mile nitrous time. From several previous dragstrips sessions I am fully aware that the 27" Hoosier puts me wayyyy out of rpms on the top end when I am on the bottle, so I can't make full quarter mile pases on them. I've struggled with them on the launch at times, and other times they have done pretty good. (still, my best 60 foots have all been with the 28" MT radial). Nonetheless, I got to the track and right away put the Hoosiers on AND at the same time adjusted the rear LCA's to be up higher. This was accomplished by moving the rear mounting point up by one bolt hole on the LCA axle mount, which too the angle of the bar to be 0 degrees or perfectly level. Typically they are 3 degrees downhill when on the next lowest bolt hole.
I wanted to experiment again with the shift points, also planning on allowing the trans to shift itself. D.A was great all day, with negative numbers during our arrival and low 200 and 300 numbers mid-afternoon. I had 94 octane Sunoco pump gas in the tank and I had no octane booster all day, even with the nitrous passes.





Pass 1:
Rear tires set at 16.6 psi each, rear koni yellows set at 1.5 each (soft-ish), 35 degrees timing on every all motor pass. Ambient temp was 53 deg with a D.A. of 206
Footbraked to 1894 rpms, slight spin on the launch with converter flashing to 4762 rpms. I shifted out of first at 6441, made the 2-3 shift at 6264, and towards the backhalf of the track watched rpms climb up high while backing off the throttle.


Timeslip and Datalog:




Video:





Pass 2:
Kept everything the same for shock and tire pressure settings. Footbrake launch at 2274 rpms and the car launched pretty good but with a little tire slip and flashed the converter to 4604 rpms. I REALLY short shifted the 1-2 shift at 5630 rpms, but let 2nd gear climb up to 6386 rpms before shifting it into 3rd and again, backing off the throttle (bright green line on upper parts of datalog) and crossing the finish line at 6196 rpms. Surprisingly, this was a new PB for the car all motor, improving on its previous best from last year's rental of 11.55 at 115.5 mph.


Timeslip and datalog:





Video:






Pass 3.
I wanted to see if I could repeat that run but with a better launch and quicker sixty foot so I softened the koni shocks by a very little on both sides. Footbrake launch at 2090 rpms and the little tire slip was still there. Converter flashed to 4538 rpms and I shifted out of first at 5911 rpms which is generally early, but not as early as the previous pass. I made the 2-3 shift at 6281 rpms and went to grab converter lockup but it was not there, so I quickly decided to make the 3-4 shift (not a great idea but I've done it a few dozen times). I didn't want to have to back off the throttle as much as the past two runs, so I shifted out of 3rd at 6055 and it dropped to 4823 rpms in overdrive! Crossed the finish line at 6060 rpms and did not expect a good timeslip at all, but this one now stands at second best for the car all-motor! wild

Timeslip and Datalog:




Video:






Pass 4. Tried going up to 17.6 psi in the rear Hoosier bias-ply tires for this pass. Went slower in the sixty foot, some spin after the footbrake launch of 2880 rpms. Converter flashed to 4804 and I shifted out of first at 6016 rpms, again, a bit lower than I usually shift it. Second gear I also shifted early, at 5869 rpms and again had no lockup under WOT so I stayed in 3rd while backing down on the throttle a little bit, to cross the finish line at 6260 rpms.


Timeslip and Datalog:




Video:







Pass 5. I turned the nitrous on for this pass, and despite not having the best time launching with the Hoosiers, they did net me 3 of my best all-motor passes so I wanted to see if they could get me a quick 1/8th mile nitrous pass before running out of rpms at 1000 foot downtrack. Bottle pressure at 950 psi, using 30 degrees of timing for the 150 wet shot and did NOT add any race-gas or octane booster this time, totally forgot to pour it in the tank all day! I footbraked from a low 1623 rpms and the car launched pretty good actually! the converter flashed at 4948 rpms, but 1st gear winged up real fast and I found myself shifting at 6488 rpms which is wayyy too high. I took 2nd gear to 6319 rpms before shifting into 3rd. I didn't bother trying the lockup in 3rd gear again, so this left me getting off the nitrous button for a period of time and then kinda easily cruised the rest of the way down the track.



Datalog and Timeslip:




Video:

 

Pass 6:
I decided to hot lap the car and made this pass within 5 mins of the last one! No changes to anything, but I wanted to see how the car would do letting the transmission shift itself so I kept it in 2, (that was the plan) until I partially screwed it up. I footbraked to 1619 rpms and then the converter flashed to around 4931 rpms. Forgetting that it was going to make the 1-2 shift itself, as the top of 1st gear arrived and it was making the 1-2 shift, I also instinctively moved the shifter from 2 to D, so I think it just went 1-2-3 real quick? Datalog shows a shift at 5923 rpms and then it stayed in 3rd for forever. As it got close to 6200 rpms I backed down on the throttle, got off the nitrous, back on the throttle, and then a little nitrous at the very end while finishing at 6202 rpms.

Datalog and Timeslip:



Video:






Pass 7.
I had just tried all I could with the 27" Hoosiers but knowing I am truly out of rpm at the top end, I put on the 28" tall MT ET street SS wheels and also moved the rear LCA back down a hole on the axle mount, so it is now back pointing downward-rearward at an angle of 3 deg downhill. I set the tire pressure of these at 18.0 and did not adjust any shock settings. Footbraked the car a little higher than usual, at 3063 rpms, which made the converter flash to 5049. The launch was good, didn't notice any tire slip and it went 1.38 in the 60 foot! For shifting, I think I did the exact same thing as the previous run and the datalog shows a gear change at 6129 rpms which I can only assume is the 2-3 shift? Climbed through 3rd gear again, actually backed off the throttle AND the nitrous was off for 1.4 seconds (see datalog) but somehow, mysteriously, went 10.55 at only 123 mph which is now my P.B. for E.T. on this car. A little bewildering here, but shows that there is more ET in the car regarding the shifts. Not a great pass, but its the current benchmark I am at!


Datalog and Timeslip:




Video:








Pass 8.
We had decided to take the cone away and fully open up the right hand starting area of the track, so I wanted to give it a go in that lane. I knew the groove at the line was going to be cold since it was not used yet today, but I tried a nitrous launch anyways. Footbrake launched the car from a lower rpm at 1827 and converter flashed to 5022 while the car spun a bit on the launch. Looking at the datalog, I again cant see the 1-2 shift so it might have happened while the tires spun and there was a gearchange at 6188 rpms. Rode out most of the pass in 3rd gear, backed off the throttle again during the backhalf, and was fully off the nitrous for the last 1.7 seconds of the run too! Woah


Timeslip and Datalog:




Video:





Pass 9.
Tommy with the supercharged Cadillac wanted to make a side by side pass since we both were running similar timeslips that day and he had a 360GoPro so I said sure and took the right lane that I actually just had trouble in. (We actually went again and switched lanes for pass #11). I decided to bring the rear tire pressure up to 19.0 psi. Footbrake launch from 1962 rpms and I was late on the tree this time when it actually did matter. The car launched decent for a low footbrake rpm but he was already out on me. I shifted this run and went from 1st into 2nd at 6443 rpms and then 2-3 at 6225 rpms. Moving around the throttle position on the top end again and finishing at 6216 rpms. It would have been a better side-by-side race if I left on time!

Timeslip and Datalog:





Video:




360 GoPro video:








Pass 10.
Kept everything the same in relation to shocks and tire pressure settings. Moved back into the left lane. Footbraked to 1731 rpms and converter flashed to 4889 rpms. The transmission shifted itself from 1-2-3 or maybe just 2-3 from what it looks like. Who knows anymore! It was then in 3rd gear forever, and like usual when it gets close to 6200 rpms I have to back off the throttle and get off the nitrous as well, this time I was off the button for just about 2 full seconds. Jeez.


Timeslip and Datalog:




Video:





Pass 11. Switched lanes with Tom in the black Cadillac for my last run of the day. Footbrake launch from a much lower rpm than usual, just a high-idle basically, 1268 rpms. Flashed the converter to 5224 rpms and unknown where the 1-2 shift is, but there was a gear change at 5994 rpms and then I kinda stayed at only 85% throttle for most of the run. Another gear change at 6184 rpms. I was off the nitrous for 2.6 seconds according to the datalog and finished the run on-motor at 6281 rpms. I accidentally dragged the video file off the memory card and deleted it without saving it, so my footage is gone. I am going to see if Tom has the 360 GoPro video from his lane, at least I came out in front that time. This 10.59 was actually my second best pass of the day, and turned out to be my 3rd best pass of all time.


Datalog and timeslip:









Now, with all that info and testing, I have a few ideas about what I can do to resolve the "running out of rpm" but all of that will be a winter season project. My really old laptop has finally died and wont turn on for the 5th day in a row, so I have to budget for a new one. I have some ambition to try to street-drive the car out to Maple Grove Racetrack in Pennsylvania during these next few weeks of November, so there's a chance I might do that. I've gotta re-think the benefit of letting the car shift on its own, something I have experimented with multiple times at the track and only had fair results. However, this time, letting it shift on its own is giving me great results. I am wondering if I leave the shifter in 2 and launch from there while letting the car do the 1-2 shift, and me doing the 2-3 shift around 6000 rpms. I am tired of over-spinning this engine, it no longer is paying off on the timeslips.

 

Lots to read so I'll ask for the Cliff's version.
What was your best NA 60' and what were the settings?
You set the LCA level I believe you said?
Anything there regarding the 60'?

 

I fully agree, it is way too much to read; I barely ever have the stamina to re-read it myself.

Best N/A 60 foot with the 27" Hoosiers was only 1.502 that day. (my all time N/A best 60 foot is 1.44 with the MT radials 28"). I moved my LCA bars to be dead-level. zero degrees for all 6 passes with the Hoosiers (4 all motor and 2 on nitrous)

On the day I had a few personal bests but none that involved a 60 foot time.
Pass #2 of the day was my current all-motor PB of 11.47 at 117.20
Pass #7 of the day was my current 150 nitrous shot PB of 10.55 at 123.3 mph (and 6.64 at 104.7mph in the 8th) but out of rpms and off the nitrous through the finish.


My overall issue to solve is running out of rpms in 3rd gear AND now I am seeing newly recognized gains in E.T. when I am letting the transmission shift itself 1-2-3, which was not the case previously. Now it seems it wants to be shifted sooner and lower in the rpm band.

 

I edited my hastily typed reply above to make sense of the last sentence.
That was intended to ask: do you feel the level LCA's contributed to a better 60' on the new tires? Yes is the take away I get. Which is interesting.
Also interesting is that the taller tire, tire type notwithstanding, is still your 60' PB. My best 60 came about with a change in gear ratio. From 3.70 to 3.27 (due to an emergency swap after I broke the 3.70 pinion). I can only guess that the reduced torque to the tires gave them a better chance to hook rather than being overwhelmed. Might be that the taller just makes that bit of difference.

FTR: If I could nail a 1.50 60' rather than my own best of 1.70 flat, I'll see 11's on a good day. That is if 2/10ths gained at the start really is double that at the stripe.
That you're racing at a sea level DA really pays dividends. I miss it tremendously. Correction here shows 6 tenths and 5 MPH from the 4000' DA of the day.

Is your season done?
BTW: Thanks for sharing all that data and your experiences. It's inspirational (true!) and now that I'm back in the game, it's great to compare notes.

 

Hmmm, I can't really tell! I didn't see enough of a difference in the 60 foot on paper to confirm my theory actually. I've used the 27" hoosiers several times without any bar adjustments and they seemed to act the same in comparison? I also wonder if you are on to something about the taller tire might be acting a little better at not overwhelming the suspension/contact-patch at the hit too. I'll definitely keep this discussion going and making passes as long as I need to, but this winter season might bring some new rear drag-strip oriented shocks and a converter re-stall so I am also going to have some new variables come springtime!

I'll get into more detail with my winter project list later on, but I am actually hoping that my season is not yet over here for 2025. If I can get my nitrous tank filled and pack some tools up, I am strongly considering going to Maple Grove racetrack (Pennsylvania) either this Saturday or next Saturday for a test and tune. I've been to plenty of car shows and spectated at the dragstrip a whole bunch, but have actually never made a dragstrip pass at Maple Grove. The air and surface should be really good, but I gotta keep in mind that its about a 2.5 hour street-drive each way!

 

With the year winding down I was determined to get the car out to a different racetrack surface before winter arrives, it was one of my goals this year especially since I didn't get to do Hot Rod Drag Week. So, on Saturday morning 11/7/25 I street drove the car about 110 miles from my house, out to Maple Grove racetrack. Wet roads, skinnies up front and drag radials in the back, car packed with tools, but the drive out there was great. I had no nitrous but was lucky enough to be able to grab a bottle from a buddy with a nitrous car as I crossed out of NJ. The weather at the track was decent, with a little bit of wind, but the D.A. stayed between 1200-1400 all day. I had 94 octane Sunoco in the tank, and did not use any race-gas octane booster at all during the whole day.












.




I had a non-working laptop with me, so I never had any opportunities to look at datalogs in between passes or even make any changes to the tune. Kinda flying blind on this venture. I also wanted to revisit letting the transmission shift 1-2 on its own since it seemed to do better last month. Torque converter lockup has become iffy, so I was a little uneasy using it on the nitrous runs. Sidenote- the scale at Maple Grove was working so i weighed my car and with me in it, total weight is 3610 pounds.



Pass 1:

All motor
I always do an all-motor pass to start the day so this was one of two. Rear MT ET street SS drag radials were set to 18.6 psi each. Both rear shocks were set to a very soft 1.0 setting and I took all air out of the rear air-bags. Ignition timing was set at 35 deg and target AFR of 12.8:1. Footbrake launch from 1412 rpms, and it flashed the converter to 4787 rpms. I left the 1-2 shift to the transmission and it shifted at 5560 rpms. I shifted the 2-3 shift at 6165 rpms. Went across the finish line at 6085 rpms and checking the log I was only about 90-93% throttle. This was a good pass, in fact it was my 3rd best all-motor pass ever! Actually the best all-motor pass on these 28" tall tires (the 11.47 and 11.50 passes were on my smaller 27" hoosier bias plys), so I was off to a good start.







Video:






Pass 2:

All motor
I switched lanes but kept everything the same on the car. However, my buddy John who was there told me to make an OPEN loop pass so I used the handheld programmer to turn off closed loop (busted laptop). Footbrake launched at 1689 rpms and it flashed the converter to 4792 rpms. I left the trans make the 1-2 shift again at 5496 rpms, and then shifted the 2-3 at 5962 rpms. Looks like I grabbed the lockup button at 5729 rpms in 3rd gear, and went across the finish line at 6017 rpms. AFR numbers were a bit lean at 13.2 and 13.4 during the run, which is why I still typically leave closed loop on during most runs. Still a good pass, and a better launch too.






Video:






Pass 3:

Nitrous pass.
Kept the shocks and tire pressure the same. Unfortunately I had a bad burnout because I think the drivers side tire didn't get wet enough in the water puddle so it only spun the passenger side tire during the burnout. I then backed up and did a small dry hop type burnout but didn't want to hold up the guy in the other lane so I got staged quickly. Footbraked the car to 1559 rpms and the tires spun at the hit, and started driving to the left. Converter flashed as I was pedaling it, and it also shifted 1-2 at about the same time. I got back into it and on the nitrous and I made the 2-3 shift at 6226 rpms. Climbed 3rd gear and then hit the nitrous system's rev limiter a few times at the 1000-foot cone, so I pedaled it slightly and got off the button, going through the finish line at 6192 rpms all motor.






Video:









Pass 4:


Nitrous pass
Switched lanes, lowered the rear tire pressure from 18.6 to 17.6 psi in both tires, while keeping shock settings the same. Decided to leave the line from a dead-idle, which was 952 rpms. Converter flashed at 4789 rpms and I had stayed off the nitrous in 1st gear to hopefully prevent it from spinning. It made the 1-2 shift at 5426 rpms and then I got on the nitrous button, making the 2-3 shift at 6201 rpms. Since lockup was becoming iffy, my only other option was to stay on the nitrous but shift it into 4th gear (overdrive) at 6205 rpms. Instead of loosing mph, it felt like it just maintained speed for the last couple hundred feet, until I crossed the finish line at 6004 rpms.








side-by-side Video:




Video:






Pass 5:

Nitrous pass:
Kept the rear tires at 17.6 psi. Knew it was going to be my last pass of the day and I was really hoping for a decent 60 foot time and a clean run. Footbraked the car to 1803 rpms and the converter flashed to 4892 rpms. Right after that, I got on the nitrous button and the car made the 1-2 shift at 5766 rpms, the 2-3 shift at 6085 rpms, and then I shifted it into overdrive (after chopping the throttle at the rpm limiter) at 6174 rpms. Still on the nitrous and in overdrive, I crossed the finish line at 6011 rpms.




Video:






Packed up all my tools and aired up the rear tires, aired up the rear air backs and cranked the rear shocks up tight. Drove home another 110 miles and got home 12.5 hours after I left. Not a bad day at all!



My Sick the Magazine GPS tracker has worked great all year; glad I have it. Occasionally it will check-in when I'm on the strip
too.












I might be able to get two more weeks of street driving the car around before taking it off the road for winter. I have some ideas for upgrades this winter that I will explore here in the coming weeks before getting things going. Most notably, a torque converter adjustment, drag race rear shocks, and I do need a tough/inexpensive laptop for this car now that my old one is out of lives.

 

First off, well done on a successful and most importantly, an enjoyable season of flogging the old 3rd gen.
Great looking, respectfully fast and certainly no trailer queen. Thanks for representing our community well. Hats off.

As for your quote:
Being without data logging is like a big step back in time for me. It used to be all analog all the time. One of the things on my spring to do list is to get my laptop and associated hardware gathered up and functional again.
Do you have an "E" transmission or is it a 4L60? Curious as to your automatic shifts and how you've dialed it into the RPM it shifts at.
As for the lockup getting iffy...let's hope it's not from abuse. The notion of applying my single disc clutch at max torque and high RPM gives me the heebie jeebies! I despise transmission re and re and hope to never have to do it again. So I protect my converter at all costs.
Our weights are the same which is interesting in a way. 3600 even all in here. Glass hood, iron heads, Spohn SFCs, Dana 44, IROC rims. (I'm 200 lbs.)
An 11.50 is my stretch goal. But it'll take a perfect storm, so to speak, to realize that. I'd probably have to refine it more into a drag racing orientated car that what it is presently. Drag shocks all around and more rear get would do it. I've got the HP and transmission/converter which is all new this year.
While your converter is apart, a look at the clutch is obviously in order.

Thanks again for all of the data.

 

thanks dude! I had a good time this year despite only getting to the track 4 times and a few big car shows. My speedometer cable is still busted (and has been since June) so my odometer on the dashboard hardly logged any actual miles this year, but in truth I had a blast. I'll redo the speedo cable routing this winter when I have the transmission out and get the converter reworked at Yank.

This transmission is not Electronically controlled in any way; its the top level build that Dana at ProBuilt automatics offers. The only electronics going to it are for Torque Converter Lockup and thats just powered by my oem fog-light switch that I activate by hand. The trans has the well-liked TransGo shift kit. The Yank converter reduced the rpm drop in between shifts a LOT compared to my Edge racing converter. The Yank flashes hard and gets the car off the line so much quicker than the edge did too, but I'm certainly causing it havoc by frequently locking it up on the track, at WOT, on the nitrous, sometimes hot-lapping! I'll be calling Yank int he next week or so, but I think my intentions are to refresh the lockup clutch (or upgrade it to a triple disc?), and certainly drop the stall from a 3800 to a 3400, (possibly 3600) in order to keep me off the rev limiter at the top end and more in my torque curve. This engine is just not a high-revving hungry type of engine. It likes it between 5000-6000 rpms and I want to keep the rear gears the same at 3.91 so taking a bite out of the converter is my best bet.

 

Which Edge converter did you originally have?
Mine is a 3800 "Street Edge" model that through conversations with Andre was his recommendation.
Not sure if that 3800 is the true stall (as in a transbrake kind of deal) as I can only push to a little more than 2k before I start to creep. It does however easily flash past 4000 at the hit. As you've described, shift recovery is excellent with mine as well. Shift at 6500 and it never sees less than 5000. That said, this is observed and not logged. At least not yet anyway. Andre also stressed his high RPM efficiency and was stated at something like 95%. I'm am however calculating about 7-10% slip at the top. (Again, need that data logging).

When we were building the LS3 '69 C10, Yank said that their triple disc clutch would ultimately make the truck slower in the 1/4. My guess is this is due to the increased mass.
My S/S racing forum friends go with an internally lightened TH350 as it provides the quickest acceleration. No lockup converters there either. But I need my O.D. and lockup because I do occasionally see some highway cruising.

Good luck in the off season. My heap is covered and stored and won't see the light of day again until April.

 

I originally had the 9" Edge Racing converter stalled at 3400 when I put this engine into the car in February 2020. After about a year and a half I switched over to the current YANK performance converter and got the 9.5" PAS (power addee series) 3800 stall, single lockup clutch. Thats when the car started sixty footing hard and I've loved it ever since. Especially the "shift extension" or rpm drop in between shifts, which is only about 700rpms with the Yank converter compared to 1300-1600 rpms with the Edge converter.

I think my current 3800 converter is just a little too loose for the powerband that my engine seems to want. Despite the cam, valvetrain, intake engine parts that say my engine should make power higher above 6000 rpms, the truth of the matter is that on an engine dyno, on hundreds of dragstrip passes, and seat-of- the pants feel... my engine likes to be lower in the torque curve and pulling from 5000-6000 rpms. Maybe 6200 max. Even on the nitrous, I think I am blowing through the converter... when its unlocked especially. I want to be shifting this car at 6,000 rpms instead of 6300 (or letting the trans shift itself instead of my hand on the shifter) and also not be on the revv-limiter with 200 feet still left before the finish line. I also hope to not keep on relying on converter lockup at the top end anymore; I would like to just keep the lockup for highway driving as it is supposed to be.

I called Dave at Yank converters last week. I had actually also spoke to him last year about the same exact discussion points, and we both agree that I can probably accomplish these goals by getting this converter reset to a 3400 rpm stall speed. It should help me not flash the converter up so high anymore, because it was previously flashing to 4700-5100 which is past peak torque and heading downhill on the curve. It will be more responsive and still hit harder in the 60 foot compared to the previous 3400 Edge converter too. However, the shift-extension might suffer a little bit so I might have a little more rpm drop between shifts. They will also check over the converter lockup clutch and replace it if needed. I was told to stay with a single disc TC lockup clutch for my all motor and small-nitrous shot setup.

In the coming weeks I will get under the car and start disassembling everything in order to get the transmission and converter out. I am partially thinking about sending the transmission out for another refresh, but part of me thinks that if nothing appears problematic with it; well just to leave it alone. Freight shipping down to Georgia is expensive, so I might just keep the trans here untouched.

I can post cam specs, chassis dyno sheets, timeslips etc if anyone wants to dig into the math, but the sweet spot for this car is between 4500-5500 on motor and 5000-6000 rpms on the nitrous shot so thats why I want to take 400 rpms out of the converter. I have no intention of re-gearing the rear axle gear ratio or changing tire-height in the back either, so its pretty-much a converter re-stall as my best option.

 

I've also talked with Dave. Very personable and technically informative. I went with Edge (for reasons that escape me at the moment) although his (Andre from Edge) talking about his converter designs and their "efficiency" where definitely a point of interest for me. Perhaps this will mean a few MPH more at the stripe and less slip. Time will tell.
Shift recovery is similar to what you described. About 1500 which is 6500 down to 5k. Way better than the old TCI I ran which had about a 2500 RPM change. Closer to 3 k actually.

You're certainly at that point now where details really matter. Seeing as you're fixed on gearing and tires, there's little else (that I can think of) to work with regards to RPM. Maybe the converter restall will do the trick.

On a personal note, one of my paths forward is turning the car into more of a specific drag racing spec rather than what it is. And that's essentially a street car with little more than a hot rodded engine, transmission and converter. RPM at the top end is low by about 1000. Fellow racers and engine builders have often discussed how getting through the peak HP RPM range and a little beyond is what you're looking for. In my case, HP RPM is flat (or stimulated to be) from 6000-6300. That puts me at an ideal 6500 but I've not enough rear gear to make that happen. That said, if my 60' improves (hopeful for 2/10ths over my best) then the RPM follows. One of those changes to a drag spec would be to install the 90/10 from struts I just picked up. Then it's tire pressures and drag bag adjustments.
Time will tell. I just have to wait.

 

Yes, he has always been good to talk to and float ideas by. He doen't try to rush off the phone either, which is much appreciated.
Woah, almost a 3000 rpm drop between shifts is massive!! I'm glad you went with the Edge converter. I had the 3400 Edge in my TPI setup, and the TPI with the nitrous, and for the first few years with this 406 both all motor and nitrous. The most noticeable difference of the two was in the sixty foot. The 3800 yank hits hard and pulls good. However, my Edge converter actually delivered better than the yank in 3rd gear and did pull off some good timeslips. It got me in to the 11s on motor and the 10s on nitrous, so I really have very minimal to complain about with it; plus is was there for lots and lots of autocross between 2017-2022. I still have it in a box "just in case" but truthful I'll likely not need it. I had it for sale for a bit and may re-list it one day, but if anyone wants it, just ask!

I like the way you are carrying out your car's plan, especially since you will be able to pull good rpm for a sbc on the top end. You are smarter than me with the technical stuff so I am curious to see your trials and successes with cutting down the sixty foot. I have the Lakewood 90/10 struts up front and really like them. For the last two years I have had them on the car; with lots of New Jersey roadway street driving and racing around, mostly without any front sway-bar and on skinny front tires too. As you might remember, I had the drag-bags for a number of years and had intermittent success with them. Sometimes they worked great, sometimes not at all with getting them to launch the car properly. The UMI drag-bar antiroll bar I put in this past winter solved all that, forever!. What do you have for a rear shock? One of my winter purchases is a set of Viking double adjustable drag shocks for the rear of the car in order to perfectly dial in the launch. My current koni-yellow shocks are less suitable for how I want the car to come-out-of-the-hole. I have a set of Lakewood 50/50 shocks that I I tried for a while, but they have been on the shelf in a box for the past couple years. They could also be up for grabs in case anyone was interested. I am probably going to keep my current (cut-down)Moog oem style springs unless there is a set of drag springs that suits my car.


Nonetheless, getting the transmission/converter out is the next project for my car, so soo I will get it up in the air and start disassembling everything. At that time I'll run a new mecchanical speedometer cable and hopefully solve that issue once and for all too.

 

I've started a 60' thread here.
One of the subjects that came up was the launch RPM and the how much HP/TQ the engine is making down that low. Not much I know.
My question to you is, based on your data logs, can you determine how long it takes to get from the footbrake RPM to the flash stall? Certainly your car starts to move the instant you smash the gas and the 60' clock begins. Saying that though, with a 1.5x time, there can't be too much lost although arguably, there might be a couple of tenths there if you could leave and hook at 4500.
1.5 would be right in my target range just the same.

 

I didn't notice your 60foot thread until you pointed it out, glad you did, I will check that over in a few minutes.
To your question about how long it takes the converter to flash from footbrake stall, I had never yet done that math. So I decided to knuckle up and do it using the personal best ALL-MOTOR pass I have made with the car, which was on 10/24/25 at my track rental event. Pass number two of that day the car went a 1.502 sixty foot (which is an attainable goal for you I agree). I had footbraked the car to 2274 rpms at 17.082 seconds into the datalog. The converter flashed to 4604 rpms at 17.512 seconds in the datalog, resulting in a .43 second time period from footbrake launch to WOT to flash rpm. That now seems longer than I expected, but it is what the datalog shows. The car then went a 7.25 at 97 mph in the 8th mile and 11.47 at 117 mph in the 1/4 mile. Nitrous passes are different and I have that data also if needed.

I am confident that chopping 400 rpm out of hte converter will make this the perfect street/strip combination I have been seeking. Different converters from different manufacturers even at the same 3400 rpm stall speed will react different and I think the Yank 3400 is my ticket to getting the car to use more of 1st gear, and climb the tq curve instead of blowing past it. As per the chassis dyno, peak tq is 378 foot-pounds at 4550 rpm and I want to use the torque curve before it a bit too.

 

Thanks for that. .43 seconds eh?....makes you think.
It was also interesting to see that chassis dyno graph. Was it peak HP RPM at 5500 or so? That makes a difference in your approach as well. I'm not realizing enough RPM at the top as I'm crossing the stripe well below my peak HP RPM. Maybe 1000 RPM less.
Although you mention street/strip, ideally, and staying strictly in the drag racing theme, these cars should always be between peak TQ and peak HP. Further to that, some really quick racers I've chatted with extend the RPM at the top end past peak HP and run it out for another 500 RPM or so. These same guys all have monstrous converters too with stall beyond 5k. Rev range is also very tight with little more than a 1500 RPM spread. That's the converter doing it's job.
But I'm not one of those guys. I'll have to live with the converter I have and figure it out from there. It's inevitable that I'll always have to make that climb from footbrake to full beans. I also understand your need for that more all around utilization rather than specifically drag. I'm getting further away from the daily driving thing and may eventually morph into something I just race. That and getting to and from the track which is all of 25 minutes.

1.5 seconds? Up until reading these last few threads (mine and yours) I was hopeful for that but something in the 1.6's is more realistic. To go quicker will mean some wholesale changes I would think. But first up is 1.7 again.

 

I really do think you are on the path to a 1.7 second slip this year. I think I am making the right choice in changing the converter and I am also on the path to more consistent high-1.3 slips on the nitrous and probably stay right around the 1.47-1.52 all-motor sixty foots.
Year after year I tried to revv this car out, and I am not saying I won't re-explore it later. Maybe some valvetrain upgrades one year will help, but for now I am going to let it live as far off the revv limiter as I can while still going fast.
I am also excited to finally start using my rear drag radials as a set of proper drag radials. For too long I have had better success in the sixty foot with airing the radials down to 17ish psi or so but they are wadding up, sometimes unloading, spinning, and unpredictable. I am also crushing the sidewalls and seeing the zebra stripes. So, to remedy all this, a proper set of drag shocks will be purchased and I will then figure out the higher tire pressure to make the radial bite/work as it should.

I got the car up in the air this weekend, drained the trans fluid (nice bright red and no smell), removed the driveshaft, Y-pipe exhaust, and the speedo cable. Next time in the garage I will remove the trans/converter and get it boxed up for shipping back to Yank to go from 3800 to 3400. I think its unlikely I will have the transmission refreshed, but I am going to call the builder and speak with him about this.

 

Nice garage!

I'll be watching your exploits regarding the radials. They're new to me and so far I've nothing really to say about them, good or bad. I do know however, as we've touched on this before, that some of the advice I've seen given to other racers regarding the rear suspension is to have a spring that's just enough to hold up the car and have a quality shock to control it. I'm certainly lacking in both regards. Way too much spring and a garden variety non adjustable pedestrian Monroe shock absorber.

And your converter re-stall is intriguing. That too I'll be following.