Did all IROC's have 305's??? Or are there some 350's??? What years have what???

 

1985 Z28 with IROC-Z option:
Standard: 305 LG4 Carb
Optional: 305 LB9 TPI ($680)
Optional: 305 L69 H.O. Carb ($680)

1986 Z28 with IROC-Z option:
Standard: 305 LG4 Carb
Optional: 305 LB9 TPI ($695)
Note 1: 50 350 L98 TPI's were produced.
Note 2: Conjecture over whether the 305 L69 H.O. was produced on the IROC-Z. I have personally seen one Z28 without the IROC-Z option with the L69. Regardless, only 74 were produced ($695).

1987 Z28 with IROC-Z option:
Standard: 305 LG4 Carb
Optional: 305 LB9 TPI ($745)
Optional: 350 L98 TPI ($1045)

1988 - 1989 IROC-Z:
Standard: 305 LO3 TBI
Optional: 305 LB9 TPI ($745)
Optional: 350 L98 TPI ($1045)

1990 IROC-Z:
Standard: 305 LB9 TPI
Optional: 350 L98 TPI ($300)

------------------
Willie

Supercharged 1987 305 IROC-Z, Daily-Driver, Emissions-Legal.
Paxton (6-psig): 12.57 @ 111 mph.
Paxton (6-psig) & 50-hp nitrous: 12.04 @ 114 mph.
ATI D1SC (10-psig): ?

http://willie.camaro-firebird.org/

1987 "20th Anniversary Commemorative Edition" Z28 Convertible -- Super Chevy Show Class Winner, 1998.

 

As always, it is impossible to improve upon or find ANYTHING wrong with Willie's posts