look at my sig,and this is the best i got at the track,it is only my second time going but i figure i'd be in the low 15's.

60ft 2.614
1/8 10.697
1/4 16.450

why the hell is my car running so slow. i had a tune about 6 months ago,just changed
the oil and greased the suspension 5 days ago.I know in have an exhaust leak at the
driver side manifold.What could be wrong.

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1987 Trans AM GTA
305 5SPD
Hypertech airfoil
gutted maf
kn filter
High Flow Cat,
3"Walker pipe
Dynomax Super turbo Muffler
TB Coolant bypass
Lubricated by Mobil 1 Tri-Synthetic

 

Well it is 14 years old and a 305. Don't expect a lot. How many miles on the engine? Is the cam and valve springs still stock?

Looking at the 60 foot times I'd say it has no bottem end torque or you're spinning off the line.

------------------
Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.89
Best MPH on a time slip: 121.52 altitude corrected to 125.89
Altitude corrected rear wheel HP: 497.9
Best 60 foot: 1.546

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

Don't be too upset about your times. I have an '87 IROC 305 and my first run was 16.1 and run a couple of 16.3's. I was very surprised. But, I have an auto and was manually shifting at 4500 rpm's. I was also running 2:77 gears. I started to shift at 5000 and started running 15.7's and 15.8's.

Your 60' times are not that good. Probably tire spin. Once I am staged, I rev with my foot on the brake at like 1500 rpm. When the light hits I let off and floor it. I get a little spin but it recovers quickly and is fine.

I know you have a 5 speed but I'll tell you how and why I shift the way I do anyway.

Some let their cars shift for them. I don't for 2 reasons.
1. If I spin too much and need to let off a little, I will still be in first rather then second gear. With the 2:77's you will get pounded if you start off in second gear.
2. My car shifts at 4500 rpm and when this happens you fall too far out of the power band and your car will take too long to make more power. Try shifting at 5000-5300 and watch the tach as you shift. Your car will now be in the power band to keep producing power.

Try advancing your timing a bit as this should help. Advance it until it pings and then back it off a little. You have to play with it and adjust it. I am surprised a little with your et's being that you have a 5 speed. Traction is everything at the strip. Don't have it and your times will suffer greatly.

I read your mods and I didn't see an aftermarket chip. If you advance the timing you won't need one yet, at least until you do more mods which will require it. If you have one in like the Hypertech Streetrunner, take it out and run with the stock one. The Thermomaster is what you want here. The Streetrunner will slow you down. I have the time slips to prove it.

I have seen many other 305 GTA's running low 16's. Don't worry about it. How many miles are on your car? Also, if it was a hot day that could account for 2/10's of second. On a cool night you should run a little quicker.

I would first focus on your driving, not the car if it is running fine. Practice, practice, practice. Focus on your launches. With street tires, it is ideal to have a chirp and then all traction. A bad launch will kill your et's. 2.6 is bad. Mine are always like 2.2. Good luck and let me know what you find out.

 

Time to be a heart braker again. I run 14.6@93mph, in a 128,000 mile 87Z 305 with 2.73's. Just look in the sig. I run a 2.00 60'. Time for tires.

------------------
87 Z28 305 TPI, Auto, LT-1 cam (@.50 418/430, 194/199, LSA 111), roller timing set, 2.73, Gutted air boxes, K & N fillters, Dyno Max 3" cat back, 8.8 mm spirals, air foil, BFG Drag radials,170* Stat and TB bypass.
Old Best 15.414 @ 87.47.
new best 15.006 @ 89.55.
w/ drag radails 14.6 @ 93
“Fallen But Not Forgotten”

[This message has been edited by new87 (edited July 08, 2001).]

 

New87,

What do you mean by "heart breaker"?

Actually your car has many more mods than mine and you should be running faster. Your car is far from stock. Comparing your car to mine or the GTA above is comapring apples and oranges. Stock, your car would run high 15's or low 16's. Do you have time slips for your car without all the goodies? If your car ran 15.4 stock with an auto then you have a point. If you have a manual tranny than that will account for about 2/10's of sec. faster than an auto, stock to stock.

That is normal for our cars with a 305. The cam alone is much better than my stock + the extra mods that I don't have. 15.4 without the slicks is right. A very good time. With the slicks your time doesn't suprise me. Drag slicks make a huge difference.

[This message has been edited by Hurst (edited July 08, 2001).]

 

new87- Your car has a different cam and you are on drag radials, yet you are only running 14.6, or 15.0 on normal street tires.

If HURST cut a 2.0 or 1.9 60', like I'm sure you did with the dr's, He would be right around 15.2-15.4 which is close to your times.

How about I be the heartbreaker to you. I ran a 14.40@95 with my 92Z28 305 TPI, auto. I have some free mods, SLP catback, ported plenum + base, 3.42 rear. Oh yeah, thats on a Dunlop 8000 street tire too.



------------------
Jason 92Z28

 

Impressive times Jason.

How do you launch and also at what rpm do you shift at? Thanks.

 

HURST- I bring the rpm's up to about 1200 and then when I'm about to launch I quickly let go of the brake and push the gas pedal about 1/2 to 2/3's the way down. As soon as I get traction I just push it the rest of the way down. As far as shifting I just leave it in overdrive and let it shift by itself at 5k rpm. I was getting 60' ft times between 2.06 and 2.1 with this method.

Since your car is a manual this probably won't help you much. Based on your 2.6 60' it looks like you are either spinning the tires alot or feathering the clutch too much and taking off easy. How were you launching and shifting?

------------------
Jason 92Z28

 

The second paragraph of my last post, was actually meant for StormshadowGTA not Hurst.

When I was talking about cutting better 60' times two posts ago, I meant to refer to stormshadowGTA once again, instead of Hurst.

Sorry for the confusion.

------------------
Jason 92Z28

 

No problem. Thanks Jason.

 

FIX THIS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
My 87 IROC started out with a first ever run of 16.43 @ 82 MPH last year with the following-
TPI 350, auto with shift kit, SLP torque convertor, 3.27 posi rear
Flowmaster 3" cat back exhaust on Goodyear Eagle GSC's, a few of the free mods
150,000 miles on my car.
Problems with my car when I started - bad radiator, was running a little too warm, not overheating though
exhaust leak at drivers side manifold

this lets fresh air into your exhaust right in front of your O2 sensor, which will make your car run rich, and can also cause a burnt valve.

I bought new bolts and tightened everything up. ALos, did tune up, switched to synthetic oil, replaced TPS, ignition module, O2 sensor fuel filter... basica maintainence things.. how's your car as far as that goes? Make sure that your car is in good running condition.
Only "mods" I did between my first ever run where I got my 16.43 and now, were that I switched to a 160* thermostat, removed the lower porion of the airbox, removed MAF screens.
My car now runs 14.46 @ 92 MPH

[This message has been edited by Jay (edited July 15, 2001).]

 

Lets see what I've done to my car compared to yours. 1st my cam, it is only a small amount bigger than your stock cam. 2nd 3.42's compared to 2.73s is a huge diff. My stock, and I mean stock times were 15.4 thats auto with the peanut cam, Which nethier of you have. Other than that I havent done much to my car. Awaiting headers from Jet hot and a 3.23 rearend. Will see what the times are after that. Buy the way what was the weather for your 14.4 and what track(GLD, Byron, US41)? Your car is just like mine sorry to burst your bubble. Also I did that on a car with 127,000 miles, compared to your?

 

New87,

It must be in your driving because I have never, I mean never seen a stock 305 auto run 15.4's. I have seen a manual run 15.4's though. You are defintely doing something right.

As I write this I am having a new rear with 3:73's installed on my 87' IROC 305 auto along with headers, an MSD 6AL ignition and few couple small mods too. I would think that the new gears would do wonders for my best et of 15.7.