What should a 92 Z34 5speed run?

[Z34-5speed]

I was just wondering what a 92 Z34 5 speed should run in the 1/4mile, it has 125k miles. I have one and i was wondering what it should be runnning. Thanks alot.

Kyle

[Garrett8]

depending on your driving ability mid to low 15's with the mods you have listed, maybe better if you a great driver and can pull a good 60ft

[stevegasm]

Check out this site: http://www.albeedigital.com/supercoupe/articles/0-60times.html It shows the 0-60 and 1/4 mile times for stock vehicles. The closest one to yours looks like:

1991 Chevrolet Lumina Z34 7.5 15.8

I'd say low-mid 15's, since yours is a 5-speed and it's not stock.

[THe_DeTAiL3R]

Check out this site: http://www.albeedigital.com/supercoupe/articles/0-60times.html It shows the 0-60 and 1/4 mile times for stock vehicles.

1981 Pontiac Grand Prix 14.9 19.9

damn that's slow! My old 88 GP 2.8 would stomp that thing! :lol:

[stevegasm]

1981 Pontiac Grand Prix 14.9 19.9

damn that's slow! My old 88 GP 2.8 would stomp that thing! :lol:


haha yeah, back when fiberglass was unheard of... :lol: it took a lot to push those tanks. what were in those? 301ci v8s? Definately a car made for the sunday drive :P

[mfewtrail]

Kyle, figure no better than mid 15's for this time of year in the South(unless there happens to be a "cool" night to run the car)...it's too damn hot/humid here. If it was running 100% and you ran on a cool fall night though, you could probably go real low 15's.

Musclecar Review magazine ran a 15.12@90.18 in a stock 5spd Z34(from their January 1992 "muscle car of the year" article). They also had a 5spd Grand Prix SE that ran 15.40@89.64.

PS: Try swapping a stock style airbox onto the car and a new/clean paper style filter onto the car next time you plan to run it. That hot air intake you have is probably hurting more than it helps at the track(heatsoak!), especially if you're running the car in the staging lanes everytime the lines move. Take a few friends with you and make them push the car in the staging lanes, be sure to pop the hood while waiting too.

[Z34-5speed]

Thanks alot. I fixed the intake, the one that is in the pics from my cardomain has been changed considerably. I used the rubber bend and the bottom half of the air box to make a heat shield for the cone filter, gets barely lukewarm now. When i had my 93 auto Z i would make sure the car wasnt running for at least an hour and have the hood up to cool the motor. I could get a 15.7-15.9 out of it if i did this. If i ran it right after a run it would run a 16.1, every time. When i take the 92 next time i will bring the stock box with me and compare time with and without it. I have taken the car to the strip before and it only ran a 16.7@83, but i think most of that is me still learning how to launch properly, 2.6sec 60ft times do suck. I was just wondering what the car should be running compared to what it is running. Thanks again for all of the great info.

Kyle

[mfewtrail]

Like everyone was saying in your other thread, 83mph is a low trap speed(should be considerably higher despite the bad 60' times). 83mph only equates to about 170hp in one of these cars. What rpm were you shifting at?

[Z34-5speed]

Ummm..., i think it was around 6300-6500. I tried in differant places. By the time i hit the line i was still in third.

Kyle

[slick]

You should consider shifting higher next time. It will place you better in your powerband in your next gear.

And, you really need to get the Ben chip.

[mfewtrail]

You should consider shifting higher next time. It will place you better in your powerband in your next gear.

And, you really need to get the Ben chip.


I did a few searches and found what I was looking for on 284 getrag/3.4 DOHC shifpoints. Here's a quote from "BigBuls" in a thread where he calculated what should be a very close to optimal shiftpoint for a stock/near stock 5spd DOHC car.

"1-2 @6600rpm
2-3 @6650rpm
3-4 @6200rpm
4-5 @6600rpm"

Of course you're only going to need to go to third gear to cross the 1/4 mile line. If you're using 225/60/16 sized tires, then 6200rpms equates to 90mph in 3rd gear fwiw.

Here's a thread with a stock Z34/5spd 1/4 mile discussion if you're interested.
http://www.w-body.com/forum/index.php/topic,29647.0.html You'll find on one of those pages that the guy driving that car shifted at an indicated 6700-6800rpms and ended up with a best time of 14.982 @92 mph.

[Z34-5speed]

Thanks. That car is awesome. I now have some hope of eventually getting into the 14s.

Kyle

[slick]

I was just looking at your original post again, and wow, your 60' really needs to come down a lot! I was able to pull consistant 2.15-2.2's in my 93 Z34 with an auto.

[Z34-5speed]

I couldn't get near those #s with my auto, 2.4s.

Kyle

[slick]

I couldn't get near those #s with my auto, 2.4s.

Kyle


Did you brake torque any before the light would turn green? Tire pressure? Any extra stuff in the car?

I can admit that the transmission in mine was modded, but even then, a lightly modded auto 3.4 should be able to pull 2.5-3 60' times.

[Z34-5speed]

I would mildly brake tq it. 25lb tire pressure. Nothing extra. It would pull a 2.4 regurlarly(i can't spell).

Kyle

[z34_nut]

As said, your shift points have a big hand in this. I rev up to 7100, but hey, my cars a little different. You should definatly be shifting near redline. Any reason why you have been so conservative?

[Z34-5speed]

Don't want to fuck up the motor if i over-rev it. I plan on going to the track Friday. I'll have some vids for yall.

Kyle

[slick]

I would personally rev it a bit higher than what you are currently doing. It will place you much better into the next gear.

Also, lower your tire pressure a bit, take out any extra weight(spare tire, jack, subs, etc...), don't have a lot of gas in your tank(weighs a lot), and try to get a better 60'.

[z34_nut]

Well I don't think you can rev past 6800RPM. Factory limiter I believe? My car has a limiter at 7125 RPM.