corvette heads on a firebird
05-12-2010, 08:44 PM
#1
Junior Member
Thread Starter
Join Date: Aug 2008
Location: San Jose, CA
Posts: 33
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Firebird Formula 350
Engine: 350 TPI L98
Transmission: 700R4
Axle/Gears: 3.27
corvette heads on a firebird
hello i drive a 1989 firebird formula 350 and while i was at a car show a guy was telling me that u can swap out the stock L98 heads for the corvette L98 heads. Is this true?
if so what would i have to do, do i need 1989 corvette L98 heads or will any year L98 heads work?
is there any mods that need to be done or will they bolt right on?
will it give me more horsepower over stock heads?
please reply
thank u very much
if so what would i have to do, do i need 1989 corvette L98 heads or will any year L98 heads work?
is there any mods that need to be done or will they bolt right on?
will it give me more horsepower over stock heads?
please reply
thank u very much
05-12-2010, 08:57 PM
#2
Re: corvette heads on a firebird
Sure, they are just SBC heads. Only issue is they have a 90deg. bolt angle on all bolts so you'll need to mod the intake a bit and it does not have an EGR passage so your EGR will not work.
They are only about 170cc but the chambers are a good bit smaller, only around 54-56cc. They will give a bit more power but they are thin castings, especially the decks and prone to warping when they get hot. There's a significantly higher head gasket failure rate associated with these. I would only do it if you get them cheap and you know they are straight
They are only about 170cc but the chambers are a good bit smaller, only around 54-56cc. They will give a bit more power but they are thin castings, especially the decks and prone to warping when they get hot. There's a significantly higher head gasket failure rate associated with these. I would only do it if you get them cheap and you know they are straight
05-13-2010, 12:25 AM
#3
Supreme Member
iTrader: (9)
Join Date: Mar 2007
Location: Raleigh, NC
Posts: 1,804
Likes: 0
Received 2 Likes
on
2 Posts
Car: 1988 Flame Red Trans am GTA
Engine: Forged 355 4 Bolt, FIRST TPI
Transmission: 700r4
Axle/Gears: ls1 torsen 3.42 gear
Re: corvette heads on a firebird
and they have a d port exhuast design... which means you need d port style headers........ not the standard square.... really not worth the swap unless u port them.. they flow close to your stockers....
05-13-2010, 12:35 PM
#5
Re: corvette heads on a firebird
Yes the EARLY L98 Vette heads were standard exhaust port, but they did not perform any better than the Iron L98 heads.
The later L98 Vette heads, the 113s, which are also still made by GM for use on the ZZ4. Are the ones that sported that groovy "D" port exhaust. Now that D port is the only thing that makes the vette heads better than our Iron L98s. Believe me, unless your intending on porting the heads first YOU WILL NOT SEE A SUBSTANCIAL GAIN IN PERFORMANCE.
And for reference, the D ports are as small as standard ports. They bolt DIRECTLY to your STOCK MANIFOLDS with STOCK GASKETS. Heck its even a good fit!
But yeah anyway, if your going to do it port them first. otherwise just buy a set of Patriot heads.
The later L98 Vette heads, the 113s, which are also still made by GM for use on the ZZ4. Are the ones that sported that groovy "D" port exhaust. Now that D port is the only thing that makes the vette heads better than our Iron L98s. Believe me, unless your intending on porting the heads first YOU WILL NOT SEE A SUBSTANCIAL GAIN IN PERFORMANCE.
And for reference, the D ports are as small as standard ports. They bolt DIRECTLY to your STOCK MANIFOLDS with STOCK GASKETS. Heck its even a good fit!
But yeah anyway, if your going to do it port them first. otherwise just buy a set of Patriot heads.
Thread
Thread Starter
Forum
Replies
Last Post
ambainb
Camaros for Sale
11
04-25-2016 09:21 PM
