7.3 compounds with a stock turbo?

Dzchey21 · Jun 19, 2011

how many set ups like that running around?

Seen one in an OBS this weekend with a stock turbo and a gt 4202 remote mounted, made 477? If i remember right on hallers dyno, pretty impressive i thought. any thoughts, anyone else running similar?

Powerstroked162 · Jun 19, 2011

Anybody who uses a stock 7.3 turbo in a set of compounds deserves to be kicked in the nuts

Dzchey21 · Jun 19, 2011

Why whats so bad about it? Isnt a stock turbo like 58mm? isnt an A3000 57mm?

Powerstroked162 · Jun 19, 2011

Center section, drive pressure.... The turbo is a pile.

38r.... Now you got something you can work with..... Kinda

Dzchey21 · Jun 19, 2011

gated i dont see a problem, esp fuel only

lincolnlocker · Jun 20, 2011

thats cool!

dirtboy25 · Jun 20, 2011

Powerstroked162 said:
Center section, drive pressure.... The turbo is a pile.

38r.... Now you got something you can work with..... Kinda

I'm with that guy...

If I were to build a compound setup I sure wouldn't want to use the stock turbo. That's just me though. :shrug:

I guess it would all really depend on the circumstances, power goals, and/or money flow.

TheSmokinStroke2002 · Jun 20, 2011

i think it would be kind of something cool to do.

Dieselboy. · Jun 20, 2011

477 with twins ?

Stocker or not, that 4202 can do 600+ by itself. Seems like a hassle, no ?

Powerstroked162 · Jun 20, 2011

Dzchey21 said:
gated i dont see a problem, esp fuel only

It's a good thing you don't build 7.3 compound kits then..... Just saying

Do it with a 38r or don't waste your time. Guy would've been money ahead to use the 4202 as a single and be done. Sure saying you have twins is cool at some point I guess but the reality is it's a dog chit setup that is desired by nobody.

477 was his number?? I as well as many others did that on a 38r and mini-me's.... Something to ponder

jdgleason · Jun 20, 2011

Im curious to know whats wrong with the stocker? Sure theres better out there, always is. What were fuel mods dustin?

lincolnlocker · Jun 20, 2011

did it have a ic in it?

mike@haller's · Jun 20, 2011

The truck wasn't ic. It was a pretty nice setup though for the amount of money he had in it (which wasn't much). I do agree a 38r is probably a better setup as many people have proven, but as a cheap budget setup it worked alright.

Big Bore · Jun 20, 2011

Sounds like a good tow setup. Do you know what injectors he's running?

Diezel Dawg · Jun 20, 2011

Powerstroked162 said:
477 was his number?? I as well as many others did that on a 38r and mini-me's.... Something to ponder

I did 491 and 496 on a 38r and hybrids.

I dont see how adding that 4202 in with a stocker would be cheaper and easier than a 38r, especially with the price of 38rs these days.

I agree with Steve, the guy wasted a lot of time for JUST 477. what kind of tuning was he running?

Charles · Jun 20, 2011

The 42 is simply way too small to act as a fiirst stage charger on one of these engines.

The GTP38 would have been fine with a good gate and at least a GT45. People just don't understand that a compressor must be much, much bigger to provide the same flow at a fraction of the pressure like what a first stage must do. Instead of running a PR of 4.5 to 5.0 or so like it would as a single, it must move that same, or more air at a PR of ~2.0 to 2.5 or so.

Here....

This is a GT4202 compressor map:

The Green dot is running ~47lbs of boost while moving just over 90lbs/min. The Red dot is running ~20lbs of boost and moving the same flow. At 47lbs of boost that compressor will move that air with an efficiency of ~73%. At 20lbs of boost it is below the lowest listed value of 65% and technically beyond "choke" for that wheel.

In contrast.... look at that same point... just over 90lbs/min and a PR between 2 and 2.5 on this GT45 compressor map...

Bingo... We just figured out why the 42 isn't large enough for a first stage.

Big Bore · Jun 20, 2011

What year was the truck?

Jake · Jun 20, 2011

As long as is is gated properly to not overdue the pressure. I was going to start the compounds with a van turbo untill I could get a38r.

I was going to use a 45 or the bw equivalent

Powerstroked162 · Jun 20, 2011

Charles said:
The 42 is simply way too small to act as a fiirst stage charger on one of these engines.

The GTP38 would have been fine with a good gate and at least a GT45. People just don't understand that a compressor must be much, much bigger to provide the same flow at a fraction of the pressure like what a first stage must do. Instead of running a PR of 4.5 to 5.0 or so like it would as a single, it must move that same, or more air at a PR of ~2.0 to 2.5 or so.

Here....

This is a GT4202 compressor map:

The Green dot is running ~47lbs of boost while moving just over 90lbs/min. The Red dot is running ~20lbs of boost and moving the same flow. At 47lbs of boost that compressor will move that air with an efficiency of ~73%. At 20lbs of boost it is below the lowest listed value of 65% and technically beyond "choke" for that wheel.

In contrast.... look at that same point... just over 90lbs/min and a PR between 2 and 2.5 on this GT45 compressor map...

Bingo... We just figured out why the 42 isn't large enough for a first stage.

That makes to much sense.... Anyway you could scrap all that and just go off the fact that it has twins and should work?? They do it on CumminGs trucks all the time in Diesel Power mag