nothingeined

Hi i have not posted in this forum. I just have a couple of quick questions. My friend just bought a 89z28. I know I will lose if i ever i get race him, but i just wanted to know how much hp he has if it is all stock except for a cowl hood? also what hp are the rs's rated at and the v6 camaro from about 90-92? there are tons of those down here but there all beat up. i just wanted to know if i should still stay away from racing them. thanks a whole lot

fbird95

89' IROC-Z,
Z28's were discontinued in 88 nad instead called IROC-Z's untill 1990. However the Z-28 emblem was not removed from the dash, a GM error.

The 89' IROC-Z was rated at 230 hp for the 5.7 tpi 350 (only available for automatics) RPO B2L
and the 5.0 tpi 305 was rated at 195 hp (automatic and 5 speed)RPO LB9

In 91-92 the V6 3.1 liter was Rated by GM at 140 hp

nothingeined

Thanks! any info on the rs or is it the same?

puckboy60

i have a 91 rs with the 305, its rated at 170 stock horsepower i believe. they aren't the fastest cars in the world stock, but they do move. but on the other hand there are a lot of things that can be done to these cars to make them a lot faster

nothingeined

Thanks a whole lot! I bet it would move cause there are some down here that are fixed up real nice. But then again there some down here that think there rs is an unmarked corvette or something and there all stock cause street racing is not a big thing down here. Thanks again.

brodyscamaro

what part of corpus are you in? click the link in my sig to see my car - maybe you have seen it around. there used to be tons of street racing in robstown every thursday night but they opened up a 1/8th mile track there so everybody goes there to race thursday and friday night. i was gonna go there tonight but decided not to.

nothingeined

wow another fbody member here in corpus! cool! i live over here like in the korstoryz area. next to ayers. how about you? awesome ride! you any good at working with the mods and stuff or did somebody help you with yours?

brodyscamaro

who else here is from corpus? i live in calallen. i have done all the mods myself including the engine(although Pro Muffler and Automotive set up the rear end. wow first time i have seen somebody from here on the boards, thanks for the compliments

Marc 85Z28

Unfortunately it's not that simple

Power ratings for 89:

For the IROC:
5.0 TBI auto or manual - 170HP
5.0 TPI auto single cat - 195HP
5.0 TPI manual single cat - 220HP
5.0 TPI manual dual cat - 230HP
5.7 TPI auto single cat - 230HP
5.7 TPI auto dual cat - 240HP

RS:
2.8 MPFI auto or manual - 135HP
5.0 TBI auto or manual - 170HP
In 90-92 upgraded to 140HP 3.1 MPFI

Kevin91Z

Marc85Z28 is correct on the horsepower numbers. A 2000 V6 Camaro will cream a thirdgen TBI or V6.
Against a TPI car it could go either way, depending on the condition of the older car, but I would hope a V8 would beat a V6, or thats a sad blow to thirdgens...

nothingeined

sorry for all the questions but how can you tell if it is a TPI or TBI or which ever? thanks again!

RedL98Z

If it's an RS with a v8 it's tbi unless they swapped the engine.

If it's an iroc it will probably say tuned port injection on it somewhere if it's tpi, or just pop the hood and check...

Marc 85Z28

TBI has an air cleaner like a carb, black and round with a single snorkel. The TBI itself looks like a 2 barrel carb.

The TPI is a aluminum, with runners that look like a spider, like most late model FI setups.

Or, you can check the 8th digit of the VIN:
E is TBI
F is 5.0 TPI
8 is 5.7 TPI

NEVER trust the badges!

nothingeined

Thanks for all your info!