Thread: Would you buy this turbo for a conversion?

Originally Posted by Maggot4x4

eBay Motors: ISUZU NPR DIESEL TURBO 4BD1 88-91 (item 120330556026 end time Jan-16-09 16:15:15 PST)

Genuine factory turbo. Is it a good price? Would I be better using something else?

No I wouldn't. I'd go for a wastegated turbo with a slightly smaller turbine housing.
That turbo is a T25 with a T3 inlet flange and a large non-wastegated exhaust housing (A/R is 0.89).
I run a T25 which has exactly the same core and compressor, but with a 0.49 A/R turbine housing, this is the smallest turbo you can run on a 4BD1. A T28 with a 0.64 A/R housing is the next step up in size, this turbo is now sold as a GT2560. Then it's the T28 with a 0.86 A/R exhaust housing, Isuzurover fitted one of these recently.

This turbo from the same guy is worth buying.
eBay Motors: ISUZU NPR DIESEL TURBO 4BD2 NEW WITH WASTE GATE (item 110347233225 end time Mar-06-09 14:08:07 PST)

It's got a smaller exhaust housing and wastegate, but otherwise is the same thing.

Originally Posted by Dougal

This turbo from the same guy is worth buying.
eBay Motors: ISUZU NPR DIESEL TURBO 4BD2 NEW WITH WASTE GATE (item 110347233225 end time Mar-06-09 14:08:07 PST)

It's got a smaller exhaust housing and wastegate, but otherwise is the same thing.

I can understand how the smaller exhaust housing has the effect of 'concentrating ' the airflow as it exits the engine, so it can spin the wheel faster, depending on the wastegate setting, but couldn't it also stifle the engine by way of too much backpressure?.

Is the turbo advertised by that guy, the best suited to a 4BD1T?, is it a Garrett Turbo?, the way he has it angled in the pic, I can't tell!. Will that turbo fit the manifold he also has advertised?, and finally how much PSI could you safely expect out of this turbo with a bit of tweeking?.

Originally Posted by 1103.9TDI

I can understand how the smaller exhaust housing has the effect of 'concentrating ' the airflow as it exits the engine, so it can spin the wheel faster, depending on the wastegate setting, but couldn't it also stifle the engine by way of too much backpressure?.

Is the turbo advertised by that guy, the best suited to a 4BD1T?, is it a Garrett Turbo?, the way he has it angled in the pic, I can't tell!. Will that turbo fit the manifold he also has advertised?, and finally how much PSI could you safely expect out of this turbo with a bit of tweeking?.

Yes a smaller exhaust housing will give a little more backpressure at high rpm. It's all a compromise.
Bigger for more top end power or smaller for more bottom end.
The housing I run is smaller than either of those and up to 2000rpm it can still deliver more boost than backpressure (at up to 20psi). At higher rpm my exhaust and muffler is the current bottleneck.

The compressor side of those is good for up to 20psi, but will start to run outside the design limits with a good intercooler above 3000rpm on our engines.
I run mine with 20psi, no intercooler yet and it's surviving fine.
Turbo compressor map here:


Yes these are all garrett turbos, T25 family so parts and rebuild kits are dirt cheap.
They have the T3 flange so they will bolt right up to the later style angled turbo manifold.

I asked him about shipping to NZ for a manifold, he said he wouldn't. Maybe you know someone in the US who can forward one to aussie.

I asked him about shipping to NZ for a manifold, he said he wouldn't. Maybe you know someone in the US who can forward one to aussie.

Might see how much FedEx want to pickup and deliver, sure be nice to have a brand new spare turbo/manifold to go on, especially at that price!.

Originally Posted by 1103.9TDI

Might see how much FedEx want to pickup and deliver, sure be nice to have a brand new spare turbo/manifold to go on, especially at that price!.

I might be able to get it shipped to a mate in the US and have him reship it.

Originally Posted by 1103.9TDI

Might see how much FedEx want to pickup and deliver, sure be nice to have a brand new spare turbo/manifold to go on, especially at that price!.

......FeDex wanted about $200AUD for manifold and turbo door to door.........didn't think it was too expensive........I'd go for it Maggot, certainly the right price and it'll transform your Rangie!.

Buying stuff on another continent can be a pain. Been there. I'm in the US and if you need some help. I can take stuff to FedEx/ UPS etc. and send it to NZ or AUS.

Cheers,
Paul

Originally Posted by Dougal

I asked him about shipping to NZ for a manifold, he said he wouldn't. Maybe you know someone in the US who can forward one to aussie.