130mph, 26" tall slicks, what diff gears should I have?

Hey guys,

Last time out I ran 10.75 at around 129-130mph with 26" tall slicks but that was with 4.11 gears and shifting into overdrive before the line. Would I also run out of 3rd gear with 3.73's if I only want to rev to around 6700rpms?

I would like to hear from people running similar mph etc and see what rpms they are crossing the line at. I don't want to go to the effort of swapping back to 3.73's if I am only going to have to swap later on. I can also look at swapping to a 27" tall drag radial or 27.3" tall slick if needed as well to give that extra head room at the end of the track.

http://www.hotrodpitstop.com/tools.html

Have a look. Might help you out
Jake,

Quote:

---

Originally Posted by Jake@GM Motorsport

http://www.hotrodpitstop.com/tools.html

Have a look. Might help you out
Jake,

---

Thanks for the link, with guessing a 7% converter slip it said I would be right on the 6700rpm limit I wanted with 3.73's and 130mph. Have people found that this works out about right?

try this one cheers
http://www.wallaceracing.com/gear-speed.php

brett what did you end up doing with this?

i'm in a similar predicament. running fraction slower 11.4@122 with 1.63 (first outing so a bit to improve), 4.11s and 4500 convertor with 235/60/15 just hitting 4th over the line. we've got first change at 41kmh and limiter at 6900. going to push 2-3 shift a bit higher and leave it in 3rd, however not super keen buzzing the limiter.

the calc's above suggest going to a taller tyre
anyone go from 235/60/15 to 255/60/15's

hey mate,

I've ended up buying some M/T 28x9" slicks and going to run them with the 4.11's. Hopefully that will be enough to stop me hitting overdrive but it will still be close.

One thing that is helping me out is that I lock up my converter at the top of 3rd which gives that extra few hundred RPM's in that gear. :)

yeah, dale from CHE suggested that. we had a go at doing it, but with EFI live a little tricky as you have to estimate speed, which then we didn't know. but now would be 120mph or ~180kph. also bumped in Jason from Dominator when i was down at DTM automatics last week and asked about this and he said it can be done, just really shortens the life of the convertor.

PM'd M12 about this and he thinks persist with 235/60/15 as it throws everything else around, not beneficial with this hp.

so going to bump the 2-3 shift kmh, then leave it in 3rd maybe try the convertor lock-up as well.

DB, the TQ as Jason would have indicated doesnt like being locked up under WOT.
G&D used this technique on a mates car (trapped at 123mph with 3.9's) some time ago with an u/k convertor. Worked quite well and the convertor is still going strong AFAIK, although very little/no track use now.

thats the thing, we're trying to push the envelope of these things. heck, we need to push things a little, to make the improvements. i know this thing wouldn;t be making the hp without 100thou off heads and resulting 12.0:1 comp, but pretty much everyone said don't do it. same as a 6900 rev limit. same with the lock-up convertor thing, there are some dyno operators who run it in 4th to get good numbers. suppose they are covering their back in case it goes boom!

Lot of debate about the lockup either at the top of each gear or just the top end of third - me personally - done it for years - never cooked a converter - it works.
One thing I will say is though - certain converters wont like it.

Quote:

---

Originally Posted by dogsballs

thats the thing, we're trying to push the envelope of these things. heck, we need to push things a little, to make the improvements. i know this thing wouldn;t be making the hp without 100thou off heads and resulting 12.0:1 comp, but pretty much everyone said don't do it. same as a 6900 rev limit. same with the lock-up convertor thing, there are some dyno operators who run it in 4th to get good numbers. suppose they are covering their back in case it goes boom!

---

Could always buy one of these if you're "serious" ;)

" MegaRaptor-2L " This is our 10 1/2 inch Billet Converter with a Billet Clutch Apply Piston that will not flex. It has a very large carbon clutch with 29.258 square inches of clutch lining. The torque multiplication rates can be ordered in 2 to 1, 2.5 to 1 or 3 to 1. The torque multiplication of this converter will deliver an increase of up to 50 horse power to the rear wheels. The MegaRaptor-2L with its carbon fiber clutch will withstand power levels of 1000 horse power. This 10 1/2 inch converter can be ordered with stall speeds of 2000 to 5500 RPM. Fits 4L60E, 4L65E and 4L70E transmissions, 1998 on with a LS1 type motor. Will not fit 2005 Corvette, Call. Cost $795.00

http://www.partshp.com/_DSC2996.JPG

thats a big convertor!!

Hey Brett ss and dogballs,

I know this is an old thread. But how did you guys end up with tyre, converter, and gear choice?

I'm fairly new to the drag scene and only have a handfull of passes under my belt with a best of 10.91@127mph with lowerd rear springs 3k converter and 3.7:3's and 235/60/15 MT drag radials. I'm going to switch to a 26x8.5" slick and front runner's and throw some 90/10's in the front and some standard FE2 springs and shocks in the rear. but am looking for a solution to not hitting 4th gear before the line. So just wondering what worked for you guy's?
Cheers.

Dogballs,

Dont recommend 4.11's.....................Dont want to regret selling you that diff!!! Maybe wouldn't have lasted many passes anyway being pintara gear's.....;)

hi mate if you were going to stick to a radial would of said step up to a 255/60/15 et street which is 27 inch !!!would help on the launch with more sidewall!!!! going full slicks !!! either step up like me and brett ss did and fit 28x9 slicks which actually measure 27.3 inch!!!!! or 3.45 diff gears!!!! with 26 inch radials i was maxing out 3.73s at 6500 rpm at 134.8mph fitted 28x9 slicks went 140.8mph then went 3.45s went 142.8mph limited testing cheers

Quote:

---

Originally Posted by blnls1

Hey Brett ss and dogballs,

I know this is an old thread. But how did you guys end up with tyre, converter, and gear choice?

I'm fairly new to the drag scene and only have a handfull of passes under my belt with a best of 10.91@127mph with lowerd rear springs 3k converter and 3.7:3's and 235/60/15 MT drag radials. I'm going to switch to a 26x8.5" slick and front runner's and throw some 90/10's in the front and some standard FE2 springs and shocks in the rear. but am looking for a solution to not hitting 4th gear before the line. So just wondering what worked for you guy's?
Cheers.

---

Hey mate,

With 3.73's you will be fine for a while with a 26x8.5" slick. With those I was hitting overdrive with the 26" tall slicks but I wouldn't have been hitting it with 3.73's. I did end up running the 28x9" slicks and they worked well with poly air bags and 8mm spacers with a little inner guard "massaging". Running them allowed me to not hit overdrive but I didn't run any faster that day as track prep was terrible and it was stinking hot. Overall still with the gearing and tyre choice you have and you should be fine. BTW I ran a 1.57 60' time at Heathcote on those same slicks.

Thanks ittwgn, perfect info.
What sort of hp you at to get up around 140mph?

Hey Brett,
Thanks for the info. My best 60ft with the current above mentioned setup and 235/60/15 MT ET streets is 1.57sec. Been doin some searching in between posts and do you guys think there is anything to gain going to a 26x8 slick? Correct me if im wrong, and i probably am but isn't a 235/60/15 the same diameter as a 26" slick? So maybe wouldn't help me not to hit 4th gear before the finish line?

ittwgn,
Any problems fitting a 255/60/15 MT ET under the back of a VZ?

http://i603.photobucket.com/albums/t...IMG_0383-1.jpg

Quote:

---

Originally Posted by blnls1

Hey Brett,
Thanks for the info. My best 60ft with the current above mentioned setup and 235/60/15 MT ET streets is 1.57sec. Been doin some searching in between posts and do you guys think there is anything to gain going to a 26x8 slick? Correct me if im wrong, and i probably am but isn't a 235/60/15 the same diameter as a 26" slick? So maybe wouldn't help me not to hit 4th gear before the finish line?

ittwgn,
Any problems fitting a 255/60/15 MT ET under the back of a VZ?

http://i603.photobucket.com/albums/t...IMG_0383-1.jpg

---

Good work mate, I assume that 60' time was at Calder? If so the prep has usually been better there than Heathcote. My best 60' time on drag radials was 1.66 at Heathcote as I needed to pedal it off the line.

I don't really think you will 60' heaps better if you aren't getting wheelspin now and with slicks if you are running lower tyre pressures you will probably lose a little mph due to the lower pressures and higher rolling resistance. I tested this theory on the same day by running the same drag radials and slicks you have and even though I picked up some 60' with the slicks I went 2mph slower.

Yeah there are some traction issue's getting off the line, have to be carefull with the throttle application.
Might just go with some 90/10's in the front and standard fe2 springs and shocks in the rear. Maybe play with the shift points and limiter and see what I can get out of that......??????
Will post results.

So are you guys all still running stock A4 4L60E auto's ?

Quote:

---

Originally Posted by Brett SS

Good work mate, I assume that 60' time was at Calder? .

---

Yeah first pass me and the car had at Calder. Defiantly a better track.

Quote:

---

Originally Posted by cjf

So are you guys all still running stock A4 4L60E auto's ?

---

No. Still 4l60e but not stock.

Quote:

---

Originally Posted by blnls1

Yeah there are some traction issue's getting off the line, have to be carefull with the throttle application.
Might just go with some 90/10's in the front and standard fe2 springs and shocks in the rear. Maybe play with the shift points and limiter and see what I can get out of that......??????
Will post results.

---

dogsballs said he already had 90/10's in that car already

Quote:

---

Originally Posted by blnls1

Yeah there are some traction issue's getting off the line, have to be carefull with the throttle application.
Might just go with some 90/10's in the front and standard fe2 springs and shocks in the rear. Maybe play with the shift points and limiter and see what I can get out of that......??????
Will post results.

---

If you are bordering on traction now then getting full slicks will make it easier, I went from pedalling it off the line to being able to mash it full throttle. I'm already running 90/10's in the front with standard FE2 front and rear also.

The shift points and limiter will help out a little as I always play with that but it will mainly be after the 60' mark that will help. What stall do you have again? Another thing some people do is pull out some timing around your launch RPM so that your launch is a little softer...

stick with 235/60/15, i managed 11.3@ 119 with 1.53 60ft last time at calder with excellent track prep with 21psi in the tyres and probably could've run more to get a little wheelspin. unfortunately smashed 5 crown wheel teeth (due to side loading of pinion without the little extension on the VT-VZ gears). although getting rebuilt with bigger M80 centre and VZ 4.11's. pushed first change out to 43kmh or roughly 6825, although limiter set at 6900; kept it in 3 and didn't hit the limiter over line. definitely keep the smaller 26" radial, but set the rear end with FE2 springs. that car already has 90/10's ;) , just need to get heat into those radials.

if you go to 26" slick you will loose mph and may not get better 60ft. if you go to a 28" slick or even 255/60/15, you'll go slower again, unless you do drop to 4.11's. this is without possible gains in 60ft. this is what i've learnt from a lot of back and forth with Markone2 who's probably got most out of auto 60fts and lsx racing. also, go to bigger tyre you have to play with gearing and changes. smaller 235/60/15 with the right pressure and suspension set-up will work. proven before.

Sorry to jump in here, just a quicky, will Monroe low shocks still be ok with swapping over to a taller spring for the track? Or is it worth while buying another set for track?

Cheers

Quote:

---

Originally Posted by Yianni vzCrewma

dogsballs said he already had 90/10's in that car already

---

There's been a few different owners since dogballs. The 90/10's are long gone out of this car. I replaced all the running gear when i bought it with the gear out of my VZ SS, engine, tailshaft, diff, driveshafts, interior and along with the front shockers as they were leaking badly! Pretty much nothing left in the car from when dogballs owned it.

Quote:

---

Originally Posted by vyls1wa

Sorry to jump in here, just a quicky, will Monroe low shocks still be ok with swapping over to a taller spring for the track? Or is it worth while buying another set for track?

Cheers

---

Munroe low shocks will not work with taller (stock FE2) spring.

I've already hijacked this thread enough.... will continue updating how i go in my ride thread.

http://www.ls1.com.au/forum/showthre...ct-VZ-EXEC-LS1

Thanks for everybodies advice and info so far!!:cool:

Quote:

---

Originally Posted by blnls1

Yeah there are some traction issue's getting off the line, have to be carefull with the throttle application.
Might just go with some 90/10's in the front and standard fe2 springs and shocks in the rear. Maybe play with the shift points and limiter and see what I can get out of that......??????
Will post results.

---

hi as said see how you go !!!! you can if your not already!! run cross ply front runners with radials on the back!!! from my research and i,ve done it is said to be the most stable combo of tyres!!!! your not maxing out that tyre/diff combo yet mph wise so all the gains you can get in first 100 odd ft the better!!!! cheers

Quote:

---

Originally Posted by blnls1

Munroe low shocks will not work with taller (stock FE2) spring.

---

Ok, well In Saying that, how will 90/10s go with a little lower than fe2 king springs? My front struts are in Need of replacing and wanting 90/10s, is it a case of havin to replace all springs and shocks to use the 90/10s?

why do that? man, can borrow my radial front runners if you want.

the reason for the fe2 spring is that its relatively soft and will give a full extension on the 90/10, and with it set up high you will get the weight transfer. it may work with the lowered spring, but the FE2 is a proven performer. FYI this was my 1.53 launch on radials as discussed earlier, FE2 springs and shocks, about from pedders 90/10's.

http://a5.sphotos.ak.fbcdn.net/hphot...03605577_n.jpg

Damn!! Sold

Quote:

---

Originally Posted by ittwgn

hi as said see how you go !!!! you can if your not already!! run cross ply front runners with radials on the back!!! from my research and i,ve done it is said to be the most stable combo of tyres!!!! your not maxing out that tyre/diff combo yet mph wise so all the gains you can get in first 100 odd ft the better!!!! cheers

---

I didn't think you were allowed to mix crossply and radial on the same car?

I've done it, upto 120mph it's not too bad past that though and it gets interesting. Banned on andra tracks although I ran at willowbank so go figure

ANDRA rules allow you to mix cross ply and radial down to 12.5 ET. Any quicker and you have to have both front and back the same

I have done a few......'miles' using a radial/rag mixture. Nothing wrong with it. Harden up australia!!

i can show you the email and reply from andra that cross ply fronts and radials are andra legal and as iiiiiiiiiiiiiiiiiiii said the most stable out of any setup!!!!!i,ve run 10.2 @ 134mph with et street drag radials on the rear and cross ply f/runnas on the front!!!! slicks on rear and radials on front are not allowed being unstable under braking etc cheeeeeeeeeeeeeeeeeeers radial rear c ply front yes!!! radial front slick rear no!!!

Hmm I've been running 115mph hitting limiter at 7000rpm in 3rd in my ute with the standard 3.46 gearing on a 26" slick Best et so far is 12.60's and Its a 6 spd. Putting in 3.9s next weekend with a kazz centre according to the calculator on the first page I should be doing 137mph at 7000rpm in 4th that's if I can get it on limter in 4th across the line not sure what kind of et that'll run but it reckons 9.80s lol....