S13LSx

I'm building a 5.3L TC78 turbo nissan 240sx. I have a 216/221 .580/.580 cam and I would like to throw some take off heads on it. I will be running E85 all the time so I don't want the compression to low to help the little 5.3L spool.

I was thinking about buying some 317's and having them milled down to 64-66cc.

What would the CR be for a stock 5.3L and 243's compared to 317's?

Any suggestions on budget take off heads for my setup will be appreciated.

evo462

iTrader: (27)

I had a similar quandry awhile back, the concensus was that it would be a dog out of boost and unnecessary with e85.

Johnv

Just go with the 243s, no point in milling 317s and reducing head deck thickness on a boosted LS , just gonna make it easier to push water.

trav-tech

iTrader: (1)

I agree with johnv i just ordered arp head bolts so i can swap out to a set of 243's i have laying around. I believe the comp will end up around 9.1to1 or somewhere there abouts correct me if im wrong.

S13LSx

Thanks, so the 317's are out. It's either buy some take off 243's or keep the 5.3"s for now.

I have some 241's but I'm not sure what cc they are and if they would be any better than the stock 5.3's for my application. I want to keep it around 9.0-9.5 CR with E85 and a TC78.