Thread: Boost

Lots of turbo options - how long is a piece of string

I have a borg warner turbo to go on mine when i get some other things out of the way.

I'm after a lot more than 5psi.

The injection pumps we have will not change with boost pressure. Some other countries have 4BD1-T's with a boost compensator on the injection pump, but their purpose is to reduce fuel at low boost pressure for environmental reasons. Some also had an aneroid for high altitude compensation.

Turning the fuel up when a turbo is fitted will increase the performance. And the drive pressure for the turbine will increase.

Originally Posted by clean32

rijidij has posted that his is as good as the 3.5 it replaced, with a stock turbo so that would be runing at about 5psi max?

Actually the engine it replaced was a 4.2 (a bit long in the tooth though)
Apparently 13psi is standard for a factory 4BD1T. Mine currently runs to 9psi, but I think the guy who dyno tuned it for me de-tuned it a bit for running in as it was a freshly built motor. Fresh 4BD1T's have been known to nip a piston if worked too hard when cold, so we thought we would play it safe for a while. When I get a EGT gauge I might start to experiment with boosting things up a bit.

Originally Posted by rijidij

Actually the engine it replaced was a 4.2 (a bit long in the tooth though)
Apparently 13psi is standard for a factory 4BD1T. Mine currently runs to 9psi, but I think the guy who dyno tuned it for me de-tuned it a bit for running in as it was a freshly built motor. Fresh 4BD1T's have been known to nip a piston if worked too hard when cold, so we thought we would play it safe for a while. When I get a EGT gauge I might start to experiment with boosting things up a bit.

Thanks , not to argue I was just going from my 4BD1 T workshop manual. But then it said 5psi at 3000rpm no load. Waste gate at 13psi.

So under load you are getting 9psi with the possibility for more so there must be plenty of extra pump volume.

Any turbo lag with the STD turbo, if so would you have gone for a smaller turbo? Or should I just not worry about it?

Originally Posted by clean32

Thanks , not to argue I was just going from my 4BD1 T workshop manual. But then it said 5psi at 3000rpm no load. Waste gate at 13psi.

So under load you are getting 9psi with the possibility for more so there must be plenty of extra pump volume.

Any turbo lag with the STD turbo, if so would you have gone for a smaller turbo? Or should I just not worry about it?

5psi no load at 3000rpm is just a stationary check to see if the turbo is working. 5psi is generally a waste of time, the only people running that are ricers who are paying off their bolt on turbo kit and can't afford to drop their engine compression.

I run 20psi, increased fuel to suit.
It can light up stock sized tyres on dry tarmac in second gear. Third gear on damp tarmac.
Pretty good for a 2.3t fulltime 4wd but embarasses the hell out of the wife when driving around town.

There are a range of turbos that will work, I run the smallest you can get away with to maximise low end torque, that's a T25 with the 0.49 A/R exhaust side. The largest I'd recommend is the T28 with the 0.86 A/R exhaust side that Isuzu rover is running.
There are about 4 garrett T25 and T28 options between those two as well as T3 based turbos.
I have adapter designs to bolt the T25/T28 turbos up to the T3 pattern on the manifold.

Originally Posted by rijidij

Apparently 13psi is standard for a factory 4BD1T. Mine currently runs to 9psi, but I think the guy who dyno tuned it for me de-tuned it a bit for running in as it was a freshly built motor.

I just recalled that my dyno guy didn't alter anything. He said it was set up ok for running in as it was. Maybe my boost dropped from standard because I fitted an intercooler. It's likely the waste gate is set at 13psi on a factory turbo.
Would I be right in thinking that adjusting the fuel on the pump might be all it needs to bring the boost back up, and bring the boost on quicker (reduce lag) ?

Originally Posted by clean32

Thanks , not to argue I was just going from my 4BD1 T workshop manual. But then it said 5psi at 3000rpm no load. Waste gate at 13psi.

So under load you are getting 9psi with the possibility for more so there must be plenty of extra pump volume.

Any turbo lag with the STD turbo, if so would you have gone for a smaller turbo? Or should I just not worry about it?

That's no load, you need the engine load, for more exhaust to make the turbo work

Originally Posted by Dougal

, the only people running that are ricers who are paying off their bolt on turbo kit and can't afford to drop their engine compression.

.

That's a ****take right? 5 psi on a high compression engine can make a massive difference, horses for courses

thanks guys.

I doint realy want to spin the wheels, but what i do want is to hang on up hills etc 80klm to 110klm would do the trick. so i supose just about any of the turbos mentioned will do.

next problem would be trying to keep the original aircon??