Hope that helps

 

Yes, that does help. Thanks.

But then how will an L76 intake that is designed for a 15* head work on an aftermarket 11* head? Special gaskets? Spacers?

Aren't they rolling the head 4*?

What about the deck thickness? (for stability on the spray)

 

The head is at the same angle, they roll the valve.
Deck thickness should be much better.

 

It is all bolt on stuff. No rolling decks. It is a purpose built head. No spacers or any of that, It will even accept stock l92 rocker arms.

 

So my Tony Mamo ported 90mm Fast wont work with these heads? I make great power with a set of portd and milled 241's. These heads should put me head and shoulders over my current set up. What about harland sharp rockers I have now, will they work? Am I gong to have to sell all my LS1 stuff?

 

No, your FAST 90 manifold wont work but your throttle body will work, only an L76 manifold will work (or carb'd or sheetmetal). No the HS rockers won't work either.

You'll most likely need new pushrods, rockers, and L76 manifold. You can sell your ported fast for more than you can buy the rockers and manifold together for.

Also sell your old heads with pushrods and you won't be that far off. Just head gaskets and tuning.

Marty

 

Two questions:
1. is this basically the same head as the LS7 4.0, only for the L76 intake?
2. Why make these heads for a L76 manifold since it is clearly a bottleneck?

 

Can the L76 manifold be ported for better flow?

 

It's already been asked but how much thicker is the deck compared to a stock l92 head?

 

The deck thickness is minimum .750

 

Because an L76 manifold won't be a restriction on a 346 where it is with a 408/416/427 etc. Plus you can port the manifold as well for more flow.

Marty

 

The only problem with porting the l76 is that it is a 1 piece manifold, where as the fast and ls7 for sure are 2 piece manifolds. It is much easier to get in side of them and work. You shold have no problems portmatching the l76 to the heads, but beyond that, it could get a little rough...

 

so if i wnat to put the et 265 on my lq9 6.0 i should change my fast 90?

 

If you want to let them breath you will.

If you are running 265's you shold be running
a) sheetmetal
b) Harrop or other ITB
c) Ported carb intake (probably race only setup)

Also if you want to see the benefits of the 265 on a 6.0 displacement, you better be ready to spin the ever living **** outof that thing. 8K+ rpm's

 

even if i had a twin turbos

i want to change my MTI stage 2r heads so should i go for the et 265 with the wilson manifold
or go with et 255 and keep my fast?

 

If you are running twins and a shot, I would stay away from the fast.
Anything above a ET225, you will be choking it with the fast.

How much boost will you be running?? IMHO I think you will have problems keeping your heads down on any of them...

 

until now i went 10 psi and i gined 600 hp and i will go for 20 psi and that will be my max

 

Let's keep this thread on topic.

Marty

 

all what i wanna ask is what is the best et heads and intake maniflods thats fits my application

 

Anything over 15psi (1 BAR) and it is better to O-ring and beter to run an ironblock. Otherwise do not expect it to last long.

and yeah, the FAST is not a good seal because of it being a 3 piece. You can run a LS2 ported intake.