Don_89Iroc

i wuz wondering what my IROC is SUPPOSE to do in the 1/4 mile, stock, if anybody knows, or has takin there 87-90 IROC to the track what your times were?, my IROC has 350 TPI and single cat and i think 2.77 gears? im not sure but it has rear disc brakes and its not posi, thanks 4 your help!

IROCZTWENTYGR8

iTrader: (1)

With the 2.77's I'll say around 14.4-14.5.

[This message has been edited by IROCZTWENTYGR8 (edited December 06, 2001).]

86ZZ4

Mid to high 14's.,Its kinda of unrealistic to go by internet times posted,way too many varibles to take into account,track condition,alt ,weather etc.I see a lot of cars that are basically the same mods and there can be .3-.4 diffence in ET's just by where they are from.

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86 z28 zz4 ssm lift bars ,3.73 simesed runners and a traction deficient 13.707@101.02,on a 2.16 60 ft on 295/50/15 junk street rubber ,best MPH run 13.82@102.7,69 AMX,390 4 speed sticky tires and other stuff..12.94@102.3

BitchinCamaro

Well, I ran my car when it was stock (K&Ns don't count as a mod IMO) Here was my best run.

60' 2.219
1/8 9.632 @ 74.54
1/4 14.920 @ 92.73

I hate to be one of those guys that give a million excuses for thier crappy times, but you need an honest image. This was my first time and the track (3rd run that night) When I left the track at 10:30pm it was 90*, meaning this run it was about 95* and high humidity. This is in Florida (orlando) so that accounts for the heat, also means it was at sea level basicly.

Car is a '89 Iroc 350 TPI, 700R4, 2.77 posi, single cat. In need of a tune up, plugs/wires/cap/rotor. And it was in full street trim, subs in the back, 3/4 tank of gas. Yadda yadda yadda.

Now I don't think those factors are going to pull a second off the time. But realisticly the car should have been able to pull off a 14.6-14.7.
Hope this helps you.

BuckeyeROC

Well, mine w/ 2.77 gears ran 14.8 @ 96 MPH on a G-Tech w/ stock engine and headers, exhaust, CAI, pulleys, roller rockers, AFPR, ported plenum, and a PR chip. That's with a decent amount of wheel spin on very poor street tires on the street.

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89 IROC-SuperRammed 355 w/ AFR 190's and LPE 219/219 cam-http://www.geocities.com/buckeyeroc

Steve R

I have a stock '89 GTA, convertible. I just ran a '97 6-speed formula firebird. First run I got him by a little, second run he took me by a little over a carlength. So figure mid-low 14's.

This is with 119,000 miles, mis-adjusted tranny, and in desparate need of a tuneup and some sensor resetting.

IROCZTWENTYGR8

iTrader: (1)

2.77's. I guess it would be more like mid-high 14's.



[This message has been edited by IROCZTWENTYGR8 (edited December 07, 2001).]

MikeT 88IROC350

I had several runs in the 14.4's this summer, at 95 mph. My motor, (block, heads, cam, exhaust manifolds) is still stock. I have all the other basic, first mods, though. It was a warm day, and I think I could do better on a cooler day. This was before I had the tranny worked on, so hopefully now I am quicker.

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Best ET 14.413 @95.57 without
pulling valve covers or manifolds.
Also with stock 2.77 rear end!!!

Don_89Iroc

man, i wuzzent expecting such low times!! that gives me a little confidence!! i wont get my hopes up to high though, but my friend just got a 94' Z28, its a 6 speed and im not sure what his car is suppose to run in the 1/4 but i read in car&driver, they tested a 96' Z28 and it only did 14.6 in the quarter, that wuz after they put 40,000 miles on it, but it still did better times than when it dident have any miles on the motor yet, i would just like to be able to stay w/ him

Burningblue

Some of these answers are from la la land. A box stock Irocz like yours with the 350 pulling 2.77s well prepped would run low 15s. One thing I have noticed is that as the cars get older, they get faster.

IROCThe5.7L

This post is 22 years old, haha. Well I might as well chime in. Bone stock mine went 14.8@93 with the wonderful 2.77 gears on a pretty hot summer day. A healthy L98 with the G92 package should easily go mid 14's.

3tas4me

I own a 1993 LT1 T/A 6-speed (stock) and just bought a 1990 IROC with the L98/G92. I can tell you from driving both that the LT1 is much stronger than the L98. The LT1 will run circles around the IROC.

dmccain

iTrader: (2)

I saw my friends brand new 93 Z28 run a 13.88 absolutely bone stock right after he bought it in 93. We knew and the Mustang guys knew right then and there those 4th genCamaros were ugly but they would run!

3tas4me

Original owner of my Trans Am took the car to a drag strip after he bought it. He let a friend drive it who knew how to drive and said it turned high 13's. I believe it.

Fast355

iTrader: (2)

G92 305 TPI car ran 13.90s driven well. LT1s were typically a bit quicker than that from what I have seen. LT4 Corvette was in the 12s. I had a L03 get into the mid 14s with the stock long block. I had a 94 G10 shorty van run 16.70s with a basically stock ~250K mile L03.

SbFormula

May as well chime in!

Bone stock '89 IROC-Z, MT, 305TPI, 3.08 on 91 octane

0-60mph, 7.0s
1/4 mile, 15.1s @ 91.0mph

After custom tune
0-60mph, 6.6s
1/4 mile, 14.7s @ 93.0mph

https://www.thirdgen.org/forums/diy-...89-camaro.html

chazman

iTrader: (4)

Wow! That's quite an improvement!

tom3

I don't know what mine would do in the 1/4 but the change from the 2:77 to a 3:23 rear was pretty amazing. A whole different car seems like. If you're looking more performance that would be my suggestion for the first upgrade.

SbFormula

Actually, after reading your comment, I went back to my numbers and decided to retest but this time with more accurate device: Dragy. On the street with street tires and my lack of launching skills.

So they came at:

Bone stock '89 IROC-Z, MT, 305TPI, 3.08, NOT N10, on 91 octane

0-60mph, 7.0s
1/4 mile, 15.2s @ 90.0mph

After custom tune
0-60mph, 6.7s
1/4 mile, 15.0s @ 91.5mph

Around +10HP at crank. But not more than factory advertised!

In 1989, Road and Track tested the IROC-Z equipped with the 5.0-liter LB9 and manual transmission and garnered a 0 to 60 time of 6.9 seconds and a quarter mile time of 15.0 seconds at 91.5 mph. (don't have more details).

It is what it is lol

chazman

iTrader: (4)

Of course, there is always this Motorweek test of an '89, G92, 5 speed, N10 IROC. 13.9 sec 1/4 mile.


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SbFormula

I don't know how they pulled this one off! 230HP on a 3700lbs car (driver and gas) don't add up to the numbers they get. But again, it is what it is.

EDITED:
The more I research and compare, the less I believe Motorweek's claim of 5.9sec/13.9sec. The MPH was not specified. That would mean around 102mph or a bit less if the 1/8 mile was very quick. If you look at the video, it's not like the IROC hooks hard and launches forward. There is no way you can move a 3700lbs car that fast with 230hp. You need at least 270-280hp. I call BS.

SbFormula

This is actually a good video:

Camaro 91 or 92, Convertible, L03 TBI, Transmission/rear gear not specified, 17.4s @ 74mph
Camaro 91 or 92, LB9 TPI, G92, MT, most likely 3.42, 14.7s @ 95mph
Camaro 91 or 92, L98 TPI, G92, AT, rear gear not specified, 14.6s @ 92mph

Fast355

iTrader: (2)

The G92 305 cars are absolutely that quick. 13.9 @ 100-102 is what I watched a stock one run numerous times the same day.

The GM ZZ conversion package made 308 hp claimed hp at the crankshaft and ran mid 12s in the car I worked on ~20 years ago.

SbFormula

Old debate

https://www.thirdgen.org/forums/hist...89-iroc-z.html

dmccain

iTrader: (2)

I probably seen a thousand thirdgens go down the track as a kid, I practically grew up at the dragstrip with my Dad. NEVER saw a stock Thirdgen 305 or 350 run better than a 14.2 or so. Now with headers , gears, underdrive pulleys and lil add ons they would easily.

chazman

iTrader: (4)

I've seen lots of low 14s too. This test is what it is, though. I wouldn't necessarily call BS, but definitely an outlier.

TransamGTA350

iTrader: (2)

This is funny. Motorweek always seemed to have the slowest 0-60 and 1/4 mile times compared to every other magazine test, except for this "ringer" apparently.

I'll add mine:
1989 GTA 350/Auto, 3.27 rear, dual cat. Only mods were air box replaced with K&N conical air filter and Magnaflow cat back. So, not exactly stock, but the mods probably didn't add anything.
14.63 @ 95mph

chazman

iTrader: (4)

I think I've mentioned this before. I had a friend with a '92 B4C, 1LE, 5.7. First time at the track, he put it in drive and mashed the pedal. 13.7 seconds.