WTB : Black Iroc-Z

[Chazman]

Originally Posted by Survivor 69/Z28

Great thread!
I have been poking around for a 5.7 Iroc myself. Good info on these cars that people on here have brought to the table.

Question: What was the scoop on the 84 Z28 with the HO motor, 5 spd, and 3.73 gears? On paper this thing was only like 175 HP if I remember correctly. However I had a buddy in high school that had one. All he did was remove the catalytic converters and put an aftermarket muffler on the car and that dang thing was beating 5.0 mustangs somehow.
Maybe his was just an apple out of the crate. I always liked the looks and the handling of the Irocs back then and even today.

The L69 HO was rated at 190 hp in the Camaro. And came out mid year on the 1983.

It was thrown together fairly urgently when the LU5 Crossfire just wasn't able to hang with 5.0 Mustangs, plus the LU5 was having trouble being certified with a stick.

It was a back to basics hotrodded smallblock, based around a bigger cam, decent compression and MUCH more free flowing exhaust which included bigger exhaust manifolds, bigger Y pipe, new free flowing cat, bigger I-pipe. The Q-jet and ignition were recalibrated and a new free flowing dual duct air cleaner housing was added. Initially they were only available with stick and 3.73s. In the blink of an eye, Z/28 and Trans Am had gotten straight line parity with the Mustang GT.



Trivia: The Crossfire intake manifold was based on the same casting as the 1969 Z/28 Crossram 302. GM reuses EVERYTHING! They reduced the runner size to increase velocity, but it really needed a lot more development. I guess the intake worked better with two 600 CFM Holleys at 7200 RPM than it it did with two 275 CFM TBs at 4500 RPM. LOL!

By the time of it's release no further development was in store for the Crossfire as GM had already moved on to develop TPI.


Trivia #2: The HO motor needed a code, since it didn't have one. As a joke, the engineers who developed it said they should call it the L69. Their boss thought that was pretty funny, and approved it!