What does it really take to go turbo?

[J Industries]

I have been reading all I can get my hands on for the last three months and tried to not ask questions but find answers (aka I do use the search button). I am now at a point where Parts are going to be purchased and money is being spent and Making sure I make the right choice is important.

The main question is choosing the right turbo. I have been all over garretts web site and going by what I have read and also by what I was told, the proper way to choose a turbo was to do the calculations and look at the turbo map.

The truck is a 4.8, cam, LT, gears, yank3000, e-fans, CAI, custom diablo tune

It seems that most truck guys run 70 - 76mm. The calculations I have done land me at the GT3582R. specs are 56 trim and 0.82AR.

the other things I was more confident about (but still up for opinions) are:
Bosch 044 pump
60lb inj.
aeromotive fuel regulator
2.5" hot tubing
3.0" dt
31x12 intercooler
3.0" cold tubing
TiAL BOV/wastegate
Synergy tuning


All that being said I'm desperately looking for constructive advice or experiences.

Thanks in advance,
future member of the turbo club.

[Botlfed]

Get ahold of allen nelson, turbo mic, quik, casey23, those 4 know pretty much the worlds wealth of knowledge on turbo stuff

[J Industries]

I agree with that but didn't want to just send a bunch of pm's, cause you never know who else might chime in with that one piece of the puzzle you forgot. I home they make their way to this thread. I really look up to them for their knowledge and what they have done with their trucks.

[pl4yboy]

The longtubes won't work for the turbo setup. They are made to dissapate heat quickly, which isn't good for turbo setups. Swap back to stock manifolds and sell the LT's to recoup some money. On a 4.8, I'd go with a 70 or slightly smaller. Who's hot pipes are you going with? Are you fabbing your own?

[J Industries]

I know the long tubes wont work, that list is what I have now. I was going to use the stock manifolds reversed and inverted with the crossover in front of the motor. I will be building everything myself.

Why a 70? besides the reason it works or that's what so and so is running.
I'm not saying your wrong but, I'm pretty good with math and all the calculations plotted on the map say go bigger to stay in the higher efficiency areas.

There must be something I'm missing.

[kyhunter89]

What will the truck be used for?

[George C]

depending all your goals the smaller turbo maybe all you want to use. The size is determined by a few things, if you keep your setup below 6k theres no need for a huge turbo. you would want a turbo that is in boost early and out of it by redline. if you were out racing then more rpms feed larger turbos but that also comes with using biggest stalls, bigger cams, lower gears.

a 58mm will work well on a 4.8 for a nice daily, but one thing to think about for price of that 58 others just go larger as it gives them room to grow. However you want to stay away from compressor surge when going to large on turbo

[J Industries]

The truck is the one you see in my avatar, its got 37's, 5.13gears but only a 6" lift. its not a huge truck. the main reason I'm doing this is to be able to run paddle tires when I go to the sand. I would like about to shoot for 500RWHP. The truck in the sand stays between 3000-5500 rpm but does hit 6k at times. One of my concerns is with sand there is a constant load for long periods at a time 15-30 of smashing. So the setup will have to be able to handle boost for a long time compared to the 1320 guys.

[pl4yboy]

I was not aware it was on a monster truck lol. A 70mm really isn't that big. I mean it would probably be too big for you, since you'll be in lower RPMs more often than people who race. I just don't want you to run out of turbo.

[George C]

For what You want 58mm is plenty, I'd be more concerned about sand then size of turbo