Thread: 4BD1T Turbo Sizing and Performance Prediction.

Originally Posted by Dougal

Your pre ic temps should be about 100c with 14psi boost.
Post temps might be reading cold too.

Egt looks accurate enough. What's the rpm at 100km/h?

They were measure just with those cheapy indoor/outdoor temp gauges with the probe cable tied to the pipe. Pre is about 120mm from the turbo outlet on stainless pipe, post is about 50mm from inlet manifold inlet on steel pipe

Originally Posted by Vern

not sure on rpm, guessing 2000? Msa 5sp, 1.003 t/c, 3.54 diffs, 285/75 tyres

I'm 2000rpm with MSA, 1.003:1 and 225/75's. You're somewhere about 1800rpm.

Originally Posted by Vern

They were measure just with those cheapy indoor/outdoor temp gauges with the probe cable tied to the pipe. Pre is about 120mm from the turbo outlet on stainless pipe, post is about 50mm from inlet manifold inlet on steel pipe

Got any foam pipe insulation to wrap around the pipe so the pipes and probes heat up closer to internal air temp?

yeah I have some 1" thick fibreglassy insulation stuff, very dense, like me.


Anyway, went for a little race to see how bad it is (took the camper off), heres' my comparison .


Hyundai Iload work van, roof rack, ladders on roof, full of electrical gear. 2+t
0-100k, 15.95sec
Isuzu LSE rangie, 2.52t
0-100k, 26.25sec

Originally Posted by Vern

Isuzu LSE rangie, 2.52t
0-100k, 26.25sec

Should be at least 10s faster than that.
Should be that quick without the turbo.

can you now see why I'm nearly in tears

Originally Posted by Vern

can you now see why I'm nearly in tears

Yes!

Okay we're not looking for tuning now. We're looking for a major problem!
Exhaust or intake blockage doesn't seem likely as you can build decent boost.
Drivetrain drag doesn't seem likely as your cruise egt and boost is okay.
Injection timing way out?

Considered bypassing the turbo and going for a drive?
How is fuel economy?

not sure on fuel economy, done around 500k (200 towing), have just over a quarter of a tank left

Originally Posted by Dougal

Yes!

Okay we're not looking for tuning now. We're looking for a major problem!
Exhaust or intake blockage doesn't seem likely as you can build decent boost.
Drivetrain drag doesn't seem likely as your cruise egt and boost is okay.
Injection timing way out?

Considered bypassing the turbo and going for a drive?
How is fuel economy?

By pass turbo or intercooler?