02anti_vnm

iTrader: (32)

ok guys so i was over at byunspeed looking to buy some cometic head gaskets for my t76 347 im buying some big bore 225 afrs and couldnt decide which to get 4.060 or 4.085 i didnt see 4.000 in a .051 thickness so itd be between one of the to. does it even matter? will it make a difference?

butler

they recommend felpro 1041 4.135 bore gasket, .041 thickness.

helicoil

iTrader: (104)

Yes, it will make a difference. Don't worry about the bore of the block, make sure the head gasket fits the 'head' too. Almost positive the big bore 225 AFR chamber measures 4.120". I used an 1162R and 1162L Felpro on my AFR 225's. It is 4.175", but they don't offer .020" increments in bore size like Cometic. I believe they have a 3.950" (1160 R&L p/n), 4.100" (1161 R&L p/n), and the 4.175" bore (1162 R&L p/n)

The Felpro 1041 is a 'composite' gasket and would work, it is 4.135" on the bore I believe, but why not use MLS, they are quite a bit better. Almost overkill really.

02anti_vnm

iTrader: (32)

i am using mls cometic mls.

and i have to stay with a .051 thickness for my compresssion ratio i already have mahle flat tops which are pushing it dont want to go any thinner

helicoil

iTrader: (104)

The Felpro MLS' measure .053" compressed. The 1041 is .041" compressed.