1980RS
09-01-2007, 08:14:03 PM
I have a project that I want to try I would like to use my L29 heads on an older 454 and that requires special head gaskets as the later engines are
mark5's. I talked to a good friend who has a boat and the dynoed the engine and it put out over 600 lbs. tq. and the rest of the range was 500 or better.
So if anyone knows of a head gasket that will mate a mark5 head to a mark4 block anything would be apreciated.
pdq67
09-02-2007, 12:40:03 AM
You do know that L-29 heads are GM's stock replacement for the old peanut port jobbers, don't you??
Smaller, true large oval shaped, about 230 or so cc intake ports and 100 cc heart-shaped fast-burn chambers. Excellent, although small exhaust ports too.
I think Scoggin D. sell's copper or brass water hole washers that fit in the headgaskets so they can be used on the Mark IV blocks.
Check into this.
pdq67
garay77n84
09-02-2007, 09:15:12 AM
I have a project that I want to try I would like to use my L29 heads on an older 454 and that requires special head gaskets as the later engines are
mark5's. I talked to a good friend who has a boat and the dynoed the engine and it put out over 600 lbs. tq. and the rest of the range was 500 or better.
So if anyone knows of a head gasket that will mate a mark5 head to a mark4 block anything would be apreciated.
depending on how old your block is you will need 1017 or 1037 fel pro gaskets
i believe if you have a 1970-1977 block you need the 1017
77-90 you need the 1037 gaskets
it is all about the cooling hoels at the bottom underneath the cylinders
call fel pro and tell them you have a gen 4 block to gen 5 head and they will ask a couple of ?'s concerning your cooling holes.
