Thread: Is this Turbo any good to use on a Isuzu.

I believe these are the numbers for the turbo which comes standard on the HS2.8:

724652-0001
GT2256V
79517

The 721843-0001 is a GT2052S, used on 2001 Ford Rangers with HS2.8 engine Part Number 721843 - Search Applications in TurboMaster

IMHO it will be a bit small for the Isuzu 4BD1. If it was the GT2256V VNT turbo also used on those engines it would be good to see how it went.

Edit: The following chart shows the GT20 series turbos to be suitable up to about 75 kW (102 HP) at pressure ratio 2.0 (about 15 psi boost pressure) from a diesel engine.



Chart and more info TurboMaster - Products - GT15-25

IMHO it will be a bit small for the Isuzu 4BD1. If it was the GT2256V VNT turbo also used on those engines it would be good to see how it went.

Yes thought it maybe a bit small the impellor seem small to me but not sure. Dougals has said in previous threads that smaller dimensions will give a quicker spool up, but perhaps this ones a bit to small.
Garry

Originally Posted by garryseries3

Yes thought it maybe a bit small the impellor seem small to me but not sure. Dougals has said in previous threads that smaller dimensions will give a quicker spool up, but perhaps this ones a bit to small.
Garry

The stock 4BD1T turbine housing is 25 series with a large A/R. This one has a 20 series turbine housing (2 sizes smaller) with small A/R (if the A/R in your 1st post was for the turbine).

So it will spool up quickly, but as engine revs increase, the waste gate will have to open to prevent the turbo from over speeding. The drive pressure will be relatively high.

The impeller in your compressor has a 52 mm exducer, which will limit your air flow/boost at higher engine revs, which combined with the high drive pressure will limit top end performance.

Dougal will have a better take on this as I have not given these small turbos much thought for a 4BD1.

The TD5 stock turbo is also a GT2052S, however, I don't know what A/R turbine housings are used in each of these. This will determine if your GT2052 will handle slightly more or less gas flow than the TD5 version.

The GT20 series appears to be comparable flow-wise to the old T25 series. Which fits with one of the guys here (was it Dranged?) who has used a TD5 turbo on his 4BD1.
So they'll be a quick spooling turbo which will work well in a tune comparable to the factory 4BD1T (90-100kw, 10-12psi boost). Beyond that they'll be running outside the map that garrett intended.

I've been running my T25 for over two years now outside the map that garrett provides. I'm okay being a reliability-tester but others probably aren't.
As John said, smaller turbos lose higher rpm performance but gain lower end. I seldom go over 3000rpm so this one has worked well for me, but I intend to try other turbos too.