I was thinking of buying a plenum and runners off of ebay and porting them,this way I would not have as much down time on my car and could take my time.My question is which years are compatible.I have a 88 350 Iroc.Thanks

 

If I remember correctly the runners are the same. I could be wrong though. As for the Plenum, you will need one from an 85-89. You are most likely running a MAF setup. 90-92 use speed density. Good luck.

Hope that helps!

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'91 Z-28 5.7, SLP 1 3/4 headers, 4 inch Mufflex/Flowmaster cat back, gutted cats, Edelbrock intake, 8.5mm Jacob wires, MSD Blaster coil, S&W subframe setup, Jacob Pro Street Ignition, complete Kenwood system.

 

An 89 plenum has no provisions for a cold-start injector. Also, in 1989, they removed the recess for the IAC passage behind the throttle body. I think you might be stuck with the 87-88 plenum if you want to keep it stock.

 

Any 85-88 plenum, runners, and throttle body will interchange with your 88 setup.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
317 RWHP, 418 RWTQ
13.23 @ 107.62 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Member: SoCal F-Bodies
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