LsxCody

iTrader: (3)

well im sitting here drinkin a few beers and looking on some diesel forums lol. i was thinking why doesnt anyone ever do a compound turbo setup on our trucks like the diesel guys do? i know a setup like that would require to run alot of boost, and that brings me to another question, can one of these motors be built to hold a massive amount of boost, say 40psi? these are just some half drunken thoughts im having and i would like to hear other ppls opinions on this.

WJ MARK

iTrader: (7)

people have tried but its more headache than its worth. These trucks can run plenty fast on simple single or twin setups . we don't need to blow 40 psi to be quicker than a diesel

marlboroman71818

because the deisel guys can run up to those high pressures they use a smaller turbo to spool faster to get the boost going and spin the larger turbos that take a long time to spool but created high amounts of airflow resulting in higher pressures. Gasoline engines generally will not accept these high boost pressures. And then you have daltons law and the ideal gas law to deal with while your trying to get it setup correctly.

schino

iTrader: (14)

i dont think it would ever be needed on a gas engine in the manor that the diesels use them. i believe there is at least one sled pulling tractor with 3 turbos in line making upwards of 120lbs of boost..

1slow01Z71

iTrader: (36)

FYI people dont even run twins to get 40psi, most guys going to the MPI twins dont even go to them till well into the 50psi range. There just isnt any reason to. Sounds good in theory but very little gains would be realized for the cost.

I still really want to see someone work out the kinks in a roots supercharger/turbo build. I think that could really be a sweet ride if it could be made to work correctly.

SincalT/A

iTrader: (16)

I got the means to do this.Problem is I dont think the ol 4.8's ready to take 25+ lbs. Of boost.You really think there would be a demand to see this.

1slow01Z71

iTrader: (36)

KB tried but had problems with boost creep and couldnt keep the boost down once the turbo spooled full. If someone figures it out, I will be doing it for sure

SincalT/A

iTrader: (16)

I know how its just a matter of money.Im not talking theroy it will work.

MikeGyver

iTrader: (5)

How about instead of compounding to build boost, compounding to build horsepower? This is what they did in the last military piston aircraft engines before jets replaced them. The first couple of turbos compressed the intake charge, and the next one or two had gears instead of compressor wheels. They were geared back into the engine, and the last of the exhaust waste heat was turned into motion.
That would take a little money to do, eh?

marlboroman71818

My thoughts on getting the roots/turbo to work are this:

A custom intake that will allow an inlet for the turbo underneath the roots blower. Also, there would need to be some type of throttle that opened at a desired rpm or pressure to keep from backfeeding boost into the turbo while it isnt spooled up enough. Then once the turbo is going the roots blower would have to be closed off. I beleive this is the only way to keep from boost creeping because the two do not create boost at the same ramp and rate and if one is less than the other then you have effectively a boost leak which causes creeping.