83Firebird420

so i am about to start a tear down, on my L98, of the top end all the way down to the headgaskets.

ill be sending the heads out to replace the valve seals. and machine it.

is there anything anyone would recomend me doing for the stock internals? such as springs or new rockers? i wont be doing the cam anytime soon so i dunno if doing that work would be worth it.

ive got some hooker 2055-1 and new fuel injectors going in.

Viprklr

iTrader: (5)

Aside from cleaning out the intake system you could replace the rockers with 1.6 to give you a little more oompf.
Porting of the intake if you so desire.

83Firebird420

ok cool thanks.

also i was under the impression that L98 heads were aluminum....i think mine are cast iron. very heavy and magnets stick to them.
is there any way i can identify them?
the marking on the engine block says:GM5.7 LG or L6

also the old headgaskets i pulled out were metal.

the vin on the hood matches all other vins on the car, the hood engine decal indicates its a 5.7 and the rpo sheet indicates its a L98. so mabey they arnt suposed to be aluminum heads?

88iroc52387

iTrader: (2)

corvettes had the aluminium head.... check the numbers 083 is iron head. unless they've been replaced they are iron.

83Firebird420

yea they have like a 7 digit number ending in 083.

is it worth buying new aluminum heads on a moter that will remain near stock? or are these heads worht keeping? i dont plan on doing much else to the motor ie cam/crank/pisons

tdavolos

iTrader: (2)

Id like to know myself

83Firebird420

well after doing some research, decent heads arnt cheap so i think ill just stick with some 1.6 rockers.

oh yeah, anyone know if these motors came with metal head gaskets ffrom the factory? or has someone already been in my motor?

jwscab

yep, metal shim gaskets are factory. Iron heads are factory L98 for F-body. With just a standard rebuild like you are doing, either 1.6 rockers, or new cam will be a nice upgrade, and above all, if you can afford it or have the time, porting the heads, intake, plenum will also add some power. I would say the 1.6 rockers will have only a slight increase, compared to better flowing heads. Try and replace the head gaskets with the thinnest composite ones you can find. I never had any luck with replacing the metal shim gaskets unless both the block and heads are trued up (tend to leak a tiny bit of coolant)

83Firebird420

thanks for the response. i thought about replacing the cam but im just not too sure i want to do that at this point(someone convince me its a good idea to do it now lol). i would like new heads but i cant justify spending 1400 on them right now. and ill probably port the intake my self.

jwscab

well, you might be able to get your heads at least mildly ported, and little bowl work, for a few hundred, which would be worth it...

83Firebird420

awsome thanks for the help and input! im about to take them to parts store to get em taken care of.