Head Swapping

[hf240z]

Originally posted by Ed

The exhaust ports are square. I intend to keep the car as close to "Daily Driver" as possible. My advantage is that I have a 24 mile commute (one way). Seven of which are on a lonely country road with lots of curves. The rest is all freeway. My freeway has about 10-15 cars in 17 miles. And I've only seen 2 cops in the last 6 years. So there have been many an opportunity to let her go.

I do want to increase horsepower without loosing the ability to drive into town and have to deal with 100 degree stop and go traffic. :mad: In other words I need to beat that Acura Integra! I already have the N42 head on it now but I can tell that the valve seals are gone. I'm really checking out my options for some more horsepower. Oh yea, did I forget to mention that new cam is going to go in at the same time (not sure which one though?).

i know i am late to reply, but, ....i can't imagine the fun you are having just to commute to and from work..... i travel 44 miles one way for a few minutes shy of an hour in the morning and 1 and half hour (or more) in the pm at 60 fwy (L.A. to Walnut).

[z-ya]

A good combo is the NA F54 block (flat tops), and an N42(square), or N47 (round) head. The resulatnt CR is 9.82:1 with the stock gasket, and 10.08:1 with the Felpro. I just built one, and will be firing it up in the next month or so. I'll be tuning it on a dyno (track only car), so I'll post some dyno plots when I'm done tuning.

Another option is to use the same block, but use a P79 or P90 head. But you will need to mill the head, and shim the cam towers to get the CR much above 8.5:1.

BTW, the stock CR for the F54 turbo is 7.4:1. This is perfect for high boost applications, but that's a whole different thread...

Pete