What is needed to install 6.1 heads on a 5.7 block? Anyone with experience in doing this?

Thanks,

 

I remember reading a while back on a website that sold heads and compared 5.7L vs 6.1L flow and stated how mildly ported 5.7L heads outperformed 6.1L heads on the flow bench and also that the 6.1L heads had a larger combustion chamber that resulted in a slight decrease in performance due to lower compression.
Again, it was a while ago I read that, but it was definately something that stuck in my head and it was the main point of 6.1L heads are not necessarily better than 5.7L heads, but i suppose it's all dependant upon your build.
Just thought I'd throw that out there.

 

DD, this came off of Moe's site; http://www.moesperformance.com/index...roducts_id=562
Looks like a bump in CR along with improve flow superior to what the 5.7 head can offer. Just messing with different ideas.

 

I thought I read somewhere that you'd need a different intake manifold???
Could be wrong?
Al.

 

Al, yes you are right an intake would be needed. How about this for a combination? http://moesperformance.com/index.php...oducts_id=1693

Adapter plate and a 84mm TB bolted to it? or http://www.compperformancegroupstore...Code=4150Style

This could be fun!!

 

Ooooooo!!!! Now we're talkin' ha ha ha. Those TB's look AWESOME!

But.....I have also read, that some of these nice new shiny intakes, are no better and in fact worse than the stock factory plastic manifolds....so you gotta' be careful I guess.
Also please be aware, it's only "What I've read". No practicle experience here of this equipment/upgrades.
Al.

 

I have been told that the OEM TB can handle 450 hp. But I have no experience with doing any of this. So it is just looking at combonations that are interesting. The four barrel TB is cable driven. But my thought was to machine a plate to the side of it and mount a OEM IAC unit. There is also a 90mm OEM style TB that has a IAC and is FBW. I see no reason one of these can't be mounted pointing up, flat on top of a carburetor type manifold with fuel rails.

 

As said before, because the 6.1 have like a 63 or 64 cc chamber, to use on a 5.7 block you need to used double head gaskets to raise the heads slightly so you can bring compression down a bit. Intake adapters are used because of the post mismatch. Everything else will bolt up as normal. Ive seen 6.1 heads sell for as little as 600 and on up to well over 1500 depending on stock heads v/s modified heads.

 

Weed, Looking around on the internet I haven't seen the adapters being offered. Who sells them? On Moes site they are offering a custom chamber to either give the 5.7 a 10.4 cr or to use on a 6.1 with a blower to lower the cr. What compression are you running?