LQ4 Tank

My original plan was to run a Procharger on my 3/4 ton Sierra (yes I'm going the forged route and sticking to low compression, that's out of the way) but have seen a lot of people running the twin screw style superchargers, and guys running turbos, which I'm in love with just don't think will prevail with a 7,000 pound truck. Which setup will provide the low end power? I know the problem with turbos is that you have to build boost and that they come on strong in the top end, so will a Procharger work better for my low end needs?

ken6881

For off idle performance a twin screw is your best bet. Whatthe truck being used for, max power goals?

JoeNova

Prochargers build boost linear to RPM. The faster the engine is spinning, the faster the procharger is turning by a direct ratio. This means that it starts low and builds boost slowly and predictably. This isn't the best for low end torque.

Twin screws and turbos both provide better low-mid range. The twin screw will provide the best low end.

LQ4 Tank

Kenne Bell practically the best? I'll start researching them. I wanna build the truck as a sleeper I guess you could say. Tired of all the pretty boys in their diesels, need to be put in their place. I wanna end up making 600 and 600, I feel like those are practical numbers and streetable.. Could be wrong however.

ken6881

Those are very realistic numbers. Keene bell, Whipple, even a eforce will get u close if not there. Just depends on what your willing to put up with, ease of instillation, and cost what will best fit your goals.

LQ4 Tank

Yeah this whole build will be spread out of the course of a couple years, haha, just trying to get a parts list going and see what kind of cost I'll be looking at. I'm getting an LS9 cam cheap off of my tuner and it'll work for what I'm going to do, just need to figure out what to do with heads and bottom end parts.

trevmust

lingenfelter is selling their ls9 cam for 389. if you got the budget just twincharge. solves both problems :-p

LQ4 Tank

I mean a cam that came OUT of an LS9, not a nicy shiny one to go IN!

stevieturbo

A twin screw would probably be best. But at that weight and moderate power goals, you could build a 427 with small turbos that would give you very good spool which would offer lots of torque at lower rpm's

JoeNova

Twin turbo 427 for 600 HP?

stevieturbo

You're ignoring the low rpm, small turbo torque aspect which would be rather handy with a 7000lb vehicle

The headline power number is almost meaningless.

LQ4 Tank

Now that just sounds expensive.. Wanna stick with my iron block 6.0, MAY bore it out but does it really make a difference?

stevieturbo

I was only suggesting the larger motor again because of torque reasons.

You could create more low rpm torque more easily, and spool any turbos faster. it would just do it all more easily.

But of course you could retain the 6.0

Ive never driven such a heavy vehicle, so I'd think every little helps. But I'd also think the weight and auto trans would load then motor up well which should also help spool any turbos used.
Again with the low overall power goals in mind, you should have access to very fast spool from a turbo setup via small turbos.

Or a twin screw blower, whichever you think might work best.

RonA

iTrader: (1)

You better bring a bigger hammer. Especially around College Station. If you are at 7000#'s a 600hp truck is not going to be anything special.

LQ4 Tank

Well there's always room for more boost

sweet99ss

iTrader: (41)

Turbo will make the biggest power by far.

LQ4 Tank

I know it'll make the most power, just not enough down low. Not enough to get a 7,000 pound aerodynamically challenged truck moving quick.

sweet99ss

iTrader: (41)

Choosing the correct size turbo you will have faaaaar more torque than a procharger and be able to make a few hundred more horsepower than a roots style blower.

bigd98

iTrader: (11)

^^^ I agree! U could even convert to e85 and get that much more TQ and HP!

LQ4 Tank

I'm interested now.. And the E85 swap just sounds difficult.