raulz28

My friend is getting ready to do a cam swap on his LQ4 T/a and first we want to know is if the stock 9.5 to 1 CR is to small? If it is what would be a good CR to get it to? The cam that we have been looking at is 227/227 .555"/.555" 117LSA(is the LSA the machine shop recommended). The car will be keeping the stock 317 heads but they will be milled a little just don't know how much yet. Is the cam too big for stock heads? Any cam recommendations would be appreciated? The goal is 400rwhp but if we can get some more without too much sacrifice to driveability then we are all for it. I own an LT1 so I'm not as knowledgeable with this platform as my own so any help is appreciated. Thanks in advance guys.

raulz28

So after some more research and talking to another machine shop we decided to go with this cam. What do you guys think about this one with the stock 317s that will maybe be milled a little to increase compression?

COMPETITION CAMS 54-428-11 LS1/LS6 XTREME RPM HIGH XR281HR $390.95 BUY ONLINE

WhiteHawk

I would get the compression at least back to 10.5 or so. Both those cams will probably feel pretty lazy around town without it. Have them "cc" or measure the heads after they mill it, too, so you know what you are dealing with. Either one of those will be OK if you get the compression up.

-Geoff

raulz28

That's the compression I was telling my friend and the machine shop that they should try and get to. The heads are 71cc if I remember correctly, how would I calculate compression if they mill them .020 for example? Lets say that they manage to get it that high is that a good sized cam or should we be aiming at something bigger?

WhiteHawk

To calcualte compression you would have to measure your heads and do the math. You can find compression calculators on the web, too. Maybe someone else has milled those heads before and checked them.

Cam choice is always a pretty personal thing. The best thing to do is find a car that you like the sound and driving charcteristics and copy it. Cams in the 220's are pretty well balanced between power and driveability - 400 will be a stretch though unless you get the compression up.

-Geoff

Need4Camaro

If you have the ability to get L92 Heads, which are relatively inexpensive then 400RWHP will be like nothing at all.