hi hope this is the right place to post this,
i have an 88 gta 350 auto i have alluminum factory heads how rare is this? it seams everybody i talk to has cast iron, but the real reason for this post is i have a set of good heads off another project that i was concidering using they are pro action heads they flow really well i am changing the cam and wanted to go with a better set of heads to match the cam however my L98 heads1.94--1.50 valves and are 58cc combustion chambers and the pro action heads have 2.02--1.60 valves and are 64 cc also i was not sure if the tpi intake would bolt up? the alluminum heads appear to have Dshaped exhaust ports the alluminum heads only need to be freshend up new springs to match cam shaved .006 to raise comp. the tpi set up is factory excluding adj. fuel presure, gutted maf, air box has been changed to a free flowing box, hypertech thermomaster chip, cool fan switch, edelbrock emision leagle headers, flowmaster catback setup, and only 60000 orignal miles so i guess the real question is use the stock heads and get them rebuilt or use the aftermarket heads if i evan can thanks

 

All Thirdgens got Iron heads. If you have aluminum, they're from a vette. ALL thirdgens had Iron.

Those heads can flow great with some porting, but if you've got your hands on some good pro-action heads, i'd probably go that route. The TPI will just just as well as any other manifold would. -meaning assuming you've got the proper bolt patterns for the given year, you should be fine. I "think" the differences pre 1987 and 1987 and above. I "think".

 

Do you know for sure they are aluminum? Lots of people think they have aluminum heads and really don't. Will a magnet stick to them?

 

they were proli swaped on there...no thirdgens got alum heads from factory

 

yes i am sure that they are aluminum, i am the second owner of this car , not sure that they are gm castings, i just figgured they were stock as it does not look like the engine has ever been apart i guess i will pop a valve cover off and look for casting # i will reply back to let you know thanks guys.

 

as far as 87 up 86 lower intake bolt pattern the pro action heads are the older bolt patern is it just the center bolts that are dif, or is it all, and can the intake be redrilled for the older pattern or not.

 

as far as 87 up 86 lower intake bolt pattern the pro action heads are the older bolt patern is it just the center bolts that are dif, or is it all, and can the intake be redrilled for the older pattern or not.

 

If you're taking the stock intake manifold off, replace it with the Edelbrock TPI intake manifold. And do some port-matching to the new heads. The stock intake stinks.