Young Performance

I think you're going to have a hard time making 750 hp from an iron headed 502 with a 6-71 and no intercooler. You will also have a hard time keeping it reliable with that small blower turning that fast and generating a ton of heat.
Eddie

slippy0217

ok i am a newbe at this what about 871 and if i change the heads to alluminum ones could i get around 700 and be reliable

Panther

On the dyno I saw just under 40 hp increase going from 5 lbs to 7 lbs boost. I think it all depends on your setup.

axapowell

Good tuning for sure...I was just throwing out a baseline that I have used in the past!

Dave

Young Performance

Absolutely.

MILD THUNDER

iTrader: (3)

My buddies old engines were 509, mild hyd roller, merlin iron heads, B&M 250, single 1050 dominator. no chiller. 697hp at 7psi at 6000rpm

he later freshened the engines, installed a larger cam, added a 871 and superchiller. he only had one set of pulleys when he dynoed, and it made 800hp at 5400, but boost gauge on the dyno showed 10psi.

In reality, had he pulled to 6000 with the cam he had, im sure he would have saw 825+. but, it wouldnt live long at 10psi with the iron heads and compression he runs. At 7psi, i'd say he has some 750's.

kylemenz1

Don't put blowers on your boat without intercoolers!!! I made the mistake and suffered the consequences. Spend the extra few buck and get the insurance that the intercoolers will give you. Put 8-71's at 5psi with intercoolers and enjoy boating all year.

MILD THUNDER

iTrader: (3)

I have lots of friends, and myself, who have been running blowers without intercoolers for years without issues. While they are nice, they aren't mandatory. It's all in the combo and setup.