Swamplizard

good stuff. HAs to be 93 octane or can 91 suffice?

Swamplizard

Flat tappet with iron gm ovals, nearly 700hp with 6psi on a 460ci, not bad at all. Still made 522ft lbs at 2000rpm.

Damn!

Baja Rooster

iTrader: (1)

Those are some nice numbers on a solid reliable build.

Generally speaking with N/A engines, are oval port heads a little better for lowend power and torque with the rectangular ports better for higher end HP? It seems that with a huffer the fuel will get shoved in there one way or another, but the ovals don't seem to get a lot of love here.

bck

It'd be nice to have a chart for the best blower size for a given rpm/ ci / desired boost etc. I've got a pair of these so I'm good.

buck35

Lol, I used to maintain a bunch of these things . couple with 300 horse electric turning them.
Is that on a vac truck, or big compressor?

bck

2 or 3k hp diesel. Some have twin turbos some have a pair of those roots

Young Performance

Those are some great numbers from a rather pedestrian setup. Good job.
My only issue is the somewhat large flat tappet cam. I've gotten to the point where I just won't do them. For me, it's not worth the hassle. Even if you do everything right in the break in, there is a risk of tearing up a lobe or lifter. All of that material has to go somewhere. And no matter what the cause, it's the builders fault if a new engine takes out a cam. I've just found that it's not worth it in the end, for me. That's not to say that you can't use a flat tappet, make power and make it live. I just won't do them anymore.
Like I said, very impressive numbers from a simple combo. Kudos.
Eddie

CDShack

I sold off square ports to go to 049 ovals on my last NA build. It was based a engine build sheet provided to us by Lingenfelter for maximum torque under 5500rpm that we followed. 049s were cleaned up, smoothed out around the valve guide, back of pocket cleaned up, big valves and port matched to the intake. 454 bored .30, Hyd. roller. Dual plane intake with 850s and a 2"spacer. Engines were originally 375hp/454 Innovations.

VE 107%. Flat torque curve from about 2500rpm on at 500+ft.lb. and maxed at 510hp up to 5800rpm. (Tanked badly after that-LOL) Great, simple motors, pushed my Kaama Scarab around for many trouble free years! This is NA of course and creating runner velocity, etc. But I became a big fan of those heads.

phragle

iTrader: (3)

While we are talking size...I am planninng/starting a 454 build with a 177. I really do not want to make more than 5oo-525 hp. 1. I want the boat to be fun, not dangerous 2. it will be airborn a lot, I dont not want to change drives more frequently than I change my socks.

Looking to cruise around 50-55 and before laying into the boost,. So do I really need a bigger blower? I will have higher static compression than a 525 sc and better cam so the actual boost shouldnt be that much except when I want to turn it up to 11...

Baja Rooster

iTrader: (1)

The only real advantage of a smaller blower is space, and the benefit of a bigger blower is its only working half as hard for the same boost giving you a cooler and safer boost.