my L98 has 154K miles on it now, and just headers/exhaust/gutted airbox mod
beefed 700r4 with 2800 stall. 3.27 gears 9 bolt rearend
timing was advanced to 10 degrees base but i might not use that anymore
suspension is full bolt ons... adjustable shocks, eibach springs, spohn LCA's torque arm (about -2 PA)
Irocz wheels with ET Streets

took it to the track yesterday and blew the 9 bolt rearend doing a 1.79 60 foot! month and a half before this, in 80 degree heat, i went 1.80-1.82 60 foots and ran 13.79-13.82's. I feel like the car is down on power right now too on that 1.79 60 foot run as i only ran 14.0 at 94 in cold weather...unless that rear end damage held me back. it feels fine in the straightline but on turns the posi binds up and cracks/bangs very loud. its shot.

not bad for a exhaust only L98 in a full weight full optioned 89 Irocz. i know alot of highly modded 12 second cars only doing 1.7x 60 foots. TPI lowend with the right gearing just BLASTS off the line. but its incredible how bad it drops off after first gear. lol i cant wait to get rid of AC and add some pullies to free up some power, and tune it abit more

oh well, time for LS1 3.42 rear end swap and hope it holds that TPI.

 

I pull 1.88 60' with my n/a 305 TPI

 

Your nine bolt should be stronger than the LS1 rear end. Mine has held up just fine over the years with many a trip down the track. 1.70's included.

 

thats what i thought...but its dead

 

Man, those are really nice 60 fts! The best I could do was a 2.1 launching off idle. When I stalled it up this happened:



Do you think that might have slowed you down? My car was at 6 degrees, and the stock fuel pressure. I turned the fuel pressure up to 49 psi, and set the timing at 10. And I seen almost no difference. I ran .1 faster, and had a very very slight increase in MPH. But I honestly think that was due to the colder weather.

Sorry to hear about your rear end. I hope the LS1 rear does not stick out too far.

 

idk, some ppl think the rear end posi with it being damaged might be slowing me down some. even tho it felt fine in the straight line on the way home and such.

i think that could be a possibility

i also had a near 3/4 tank of gas as opposed to my usual near empty to 1/4 when i race.

but i think someting might be wrong with the timing or the motor itself since the gasket install.

also i have a code 36...mass air relay...

but i have ran it at the track before with taht code on, and it ran normal!

 

I believe 36 is for the MAF burnoff. Might want to try replacing the relay. Cheap and simple.

 

i cant seem to get my 60 foot under 2.145 i had my tire psi at 25 and launched at idle no luck any tips? This is done on a kumho 711. What i did was got to the line when the third yellow lit up i smashed it and only felt like it was chirping alittle bit i guess if i ease into but i dont how much too any suggestions?

 

what are your mods, and what trap did you run? thats not to bad for a lightly moded TPI. one tip is to stage as shallow as you can so you can get a good rolling start on the timing switch.

 

Can I guess and say you have 2.77's like me?

 

i had 2.77 gears and with my 2800stall on street tires, i cut many lower 1.9x 60's and two 1.8xs...1.88 and 1.895. the converter makes all the difference tho...

on slicks i know i could have been bottom 1.8x's for sure.

the 3.27s should be good for high 1.7x for me. i already hit 1.80 and 1.79 and thats just the few times i tried it. more tweaking and i got some good launches going. i think i could hit 1.76 or so. too bad i'lll never know, cuz i doubt i'm keepin the 9 bolt.

my buddies full bolt on L98 with 3.70 gears and stock converter on street tires does low 1.9x 60's. he doesnt spin too much either with stock converter for some reason. he launches pretty good, he says he just smashes it and it goes. but runs 13.6x at 99-100. a converter/slicks on his car would really open it up. cuz i raced him a few times on street tires and matched his 60 foots but thru first he pulled a half car or so, and once in second, i start falling due to his better power and those 3.70s. he always gets me by about 1.5 cars-2cars

 

yes i have 2.77 my mods are basically headers cat catback and some free mods stock intake heads and cam. cant seem to find a place that sells some 3.45 and a 3 series posi w/ installation kit on the web. Other then tires and stall dont some suspension stuff lower 60 foot?

 

lower control arms and the relocation brackets will help give more traction. torque arm with adjustable pinion angle could give more traction too. but i dont think its necessary right away

shocks and springs are the big stuff that help get the launch goin

 

my 88 l98 has done a best of 1.97 60 ft and the only mods i have are a slp cold air and underdrives. I dont know why (this was brought up about my car in another thread) but it just hooks up everytime. I cant get the car the really do more that chirp the tires from a dead stop. I really want to do a converter, some LCA's and some relocation brackets so I can kill people from redlights. anyway thats my 2 cents.

 

i never ran my car bone stock, but even when it was bone stock on the street, if i floored it with 2.77's...it would roast the tires!!! that doesnt seem right if you floor it at the track and they dead hook, unless u got some great street tires and good track prep

 

I can dead hook at my track going wot off idle (not on the street though). But I only pull a 2.1 60 ft. Stalling it up a bit just destroyed the tires. Getting Nittos for sure next year.