I've begun piecing together my heads, cam, and intake swap. just got in my '01 Cobra intake manifold . . .

. . . and yeah I'm going to clean it.


Here's one quick question (I'm sure there'll be more)

When swapping out the B-heads to later DOHC heads, like the '04 Aviator's I'm planning on using, is there any change in compression ratio?

I only ask because I know in certain situations it changes e.g.(NPI to PI swap) even without extra shaving on the head deck. Just differences of combustion chamber etc.

 

Nevermind...figured it out, pistons are the same, as well as the combustion chamber, both are 52cc. For some reason only the 99/01 are 54cc. Thanks anyway.

 

good luck with the swap! ive always been interested in doing it to mine but cant bring myself to get rid of my bheaded intake

 

Ive thought about a c head swap but after talking to alot of headshops the general consensus is that worked b heads flow better than worked c heads in a boostb application

 

I agree..But some people will still argue C Heads flow better for boosted apps.

 

I'm hoping na svt over on SVTP will get a B lid to C lower adapter eventually. If not I may have my fiance's father, he's a metal fabricator, try to make me one.

 

iv been following that thread and im not getting my hopes up

 

Yeah, me either. Which is why I'm talking to my own fabricater.

 

The B heads don't "Flow" better, the difference is in velocity....

-------intake-----exhaust
.050---39---------34
.100---79---------71
.150---114---------97
.200---144---------119
.250---172---------132
.300---194---------138
.350---207---------141
.400---217---------144
.450---225---------145
.500---231---------146

c heads
-------intake-----exhaust
.050---40---------34
.100---88---------74
.150---118---------102
.200---151---------123
.250---178---------133
.300---201---------138
.350---211---------140
.400---221---------143
.450---229---------145
.500---233---------145

 

Make sense