If i wanted to could i put a different trubo on a hypermax system than the one thats on it? The exhaust AR# on hypermax is 1.00 to 1.05 and i think the intake is .70, i found some turbo's 1.02-1.15 and .60-.70 would it work? Would i have a problem with over boosting the engine?
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First off you need to find out what turbo comes stock with the kit.

I.e. is it a T3-style turbo, a T4, or some other brand (there are a lot of different ones, T3 and T4 exhaust flanges are pretty standard, but the rest of the turbo can vary greatly). How is the turbo attached to the engine, this will also affect what you can use.

Hopefully someone can chime in about the possible overboosting, as I don't really know the behavior of a non-wastegated turbo on a diesel engine very well, but for a general reference- a higher a/r on the turbine housing gives you a slower spool, but less restriction and more top end power. Lower A/r does the opposite. A larger compressor a/r moves more air at lower temps, but at higher lag; lower moves less air, less lag, higher temps.

Beyond that...can't help ya much.

 

the stock turbo is a AiResearch Intake side .70 Exhaust either 1.00 or 1.15 and it is a T4-T04, im not possitive but i think it mounts on the exhaust flange where the exhuast pipes meet.

 

Well, any other T4 turbo should bolt on it place of it.

You didn't really specify why you want to put on another turbo...

 

My understanding is,
A low AR will spool faster, but the max boost produced is lower.
A larger AR will spool slower, but produce more top end boost.

Now the next thing, which as far as I know has nothing to do with the AR numbers is what displacement engine was the turbo designed for?
Say it was designed for a 2.3 engine and now you are putting it on an engine 3 times larger.

1. Boost may go through the roof
2. The turbo may overspeed enough to explode
3. You may not produce 5 PSI boost.

There are to many variables to even offer a good guess.
If you want to go this route, I guess you can install a boost gauge and let off the throttle before you get to 15 PSI.
But that still will not guarantee that the turbo impeller will not explode and go through the engine if it was designed for one of those small displacement gas engines.

Consider the exhaust flow out of a 2.3 (140 cu in) gas engine running 9 to 1 compression and 5 PSI boost.
You put that on a 6.9 (420 cu in) engine running 22.5 to 1 compression.

Yes the displacement is three times as much, but the 2.3 runs three times as much RPM.
Given the CFM flow at max throttle is the same, my guess is the max boost will be 5 PSI.
But my fear is the higher compression ratio combined with the lower boost pressure will result in turbo speeds much higher than it was designed for.

With out hard facts, this is just a guess though.

 

Well, that's pretty much what I'm saying...

Without a wastegate, I don't really understand how boost is controlled on a diesel with a non-wastegated turbo (if it even can be controlled at all?)

How much boost does a hypermax system hit at peak, and what RPM does it usually come on? Does the boost "creep" if you stay in the throttle for an extended period?

 

The non wastegated turbos are just set up so the volume of air going through the turbo on the exhaust side will not exceed the boost pressure the engine can take.

The only way to adjust boost on a non waste gated turbo is with the fuel screw or the throttle.
More fuel = more boost.
Less fuel = less boost.

 

should i jsut find a turbo similar to the hypermax and just controll the boost with the fuel, or find one with a wastegate?

 

What is wrong with the turbo that you have installed now?

Since the Hypermax system uses a non waste gated turbo, changing to a waste gated system may not be that easy.

 

i dont have a turbo on my truck, i can get a hypermax pulse system brand new without the turbo for 500-800$