Ok I am buying a 1990 IROC-Z/28 with a tuned port 350, What kind of performance numbers can I look foward too?? And whats so great about it

 

A '90 L98 should run mid-high 14s depending on what condition it is in.
They have tons of low-mid range torque which is what makes them so great.

 

yep.

 

A lot of low to mid range tq due to the TPI.

Make sure you check the heater core works without dripping before buying

turn the heater on and let it run for a little bit...

If it drips the core is around 30 bucks to replace but will take a shop around 11-13 hours of labor... mine went bad as soon as I got the car. I changed it out in a weekend... prev people covered it up, when I bought it. So this would make a good price cut deal if car is priced high.

 

See below....(I know MAF vs. SD but its close stock )

 

58mm TB , stock plenum/runners, stock internals, stock manifolds, 2000 stall, a muffler, and some free mods, and i hit a 13.9 at 96 mph and that was with it being about 90f outside. 90 Iroc is the last year iroc, and the iroc with the most HP. rated at 245hp and 345 ft/lbs tq. I have never lost to a stock rustang or another stock 3rd gen. I would buy another one without thinking twice, but be prepared for things to wear out (ie: fuel injectors, pump, tranny, water pump, radiator..ect, ect)

*EDIT*
Oh i forgot, 1990 Iroc's were only produced for half a year, since the IROC contract ended. That means production numbers were way down for 1990's, making them one of the rarer 3rd gens. They will only get more rare, seeing as how most of them are not treated how they should be, and most owners don't realize what they have.

 

My dad has his own auto repair so I don't have to worry bout paying smack

Turns out the car's valve seals leak on start up but it goes away

 

WTF??? I paid $17 for mine 3 weeks ago and it took me 2 hours to replace it...someone is making a killing on their flat shop rates.

 

They all do that unless they have been fixed already.

 

Yeah, they sure do....mine have been leaking for about 2 years, but they haven't gotten any worse. I'm swappin' heads soon, so I'm just gonna wait it out.

 

For real, I remember swapping the part on my 86 and it took all of a couple of hours without the proper tools at that. And being my first attempt at ever tackling a heater core. 13 hours is insane.

Will

 

It took me around a full weekend on a firebird... I had to pull the dash pad, lower kick panels on both sides, drop the steering column and then take the two bolts that hook that dash to the firewall... Lay the dash down in the seats and then take the 4 screws that hold the core lid on it... then cut my OEM hoses off cause I couldn't get them to come off the old core... put the new core back on... hacksaw old piping off the old one to rig it back up (since I spliced a hose) and then reassemble the dash.

Oh and I pulled the gauge console out cause I was afraid it might twist and crack a bezel.

My valve stem seals leak a little bit too on start up but not any big deal... I got a new 383 eventually hopefully.

 

Ummm, ouch. It was my F bird that took me two hours to change. The IROC was so long ago that I don't remember exactly how long it took, but no more than 4 hours to be sure.

 

Yeah, might have been due to me being slow... I know I messed around the heater core hoses for awhile though.