Now I know every one with a 660 wants to do the 3x00 swap, but that’s allot of work right, and for those of you that tryed mating the 3x00 heads with a 3.1 intake you know that there is about 1\8" that is not matched, and you’ll also know that the "D" port is ALOT bigger than the little "o" that the 3.1's have.

So here’s what I did with my old 94 Z.

I had a extra set of 3.1 heads, and a set of 3400 heads, in short I put them side by side and made my 3.1 heads an exact replica of the 3400 heads, also I matched the manifolds to the heads, in short I made "fast burn 3.1 heads"

Also I didn’t touch the intake side, I wasn’t that good at that time.


at the track i ran 1\2 a secound faster 15.9-15.3 and 10 MPH faster 84-94.
also i got 6 MPG better.

Chris



'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

hmm...do you have any pics of the process

most people just swap on the 3x00 intake along with the heads.

along with the injector harness, timing cover, water pump, fule rail.... i know, ive done it too,

that was easer so i posted it.

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

its not really that hard to do the hybrid swap, but interesting that you thought of this, pics would be nice. why not put the 3x00 intake on too?


cavaliers been laid to rest
The saturn is being born
a new cavalier is in the mist

as ive said, the intake runners from the lower plenum to the heads will not match, 3x00's use "line of site" were as the 3.1\2.8's do not.

as far to how hard it is..... when i did it there was only one other persion that did it...

Colin.

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08