Thread: Rebuild kits 4BD1 v 4BD1T

Originally Posted by 110Landy86

Hi All,

Planning to rebuild 4BD1 in the near future. Given that I'm looking to turbocharge the engine, i was thinking of rebuilding using a 4BD1T rebuild kit which I can purchase from local Isuzu dealer.

Question is, are there any differences between the 4bd1t and 4bd1 engines (excluding the oil squirters) that won't make this possible?

As I understand, the 4BD1T rebuild kit comes with stronger components?

Ultimately, I'm looking to build a heavy duty engine.

Any other recommendations w.r.t rebuild kits on the market are welcome.

I will add that I already have a 4BD1 engine in my possession otherwise I'd go with a 4BD1T variant.

Thanks Joe

Rebuild kits for 4bd1t is not nessaceraliy stronger but just slightly different....you may find ring-bore clearances differ between both,you may find piston skirt height varies... So all in all not much difference really so I cannot see why there is a problem...i was tempted to rebuild mine but at 400k it don't really need it as it still runs sweet...

Originally Posted by 110Landy86

Hi All,

Planning to rebuild 4BD1 in the near future. Given that I'm looking to turbocharge the engine, i was thinking of rebuilding using a 4BD1T rebuild kit which I can purchase from local Isuzu dealer.

Question is, are there any differences between the 4bd1t and 4bd1 engines (excluding the oil squirters) that won't make this possible?

As I understand, the 4BD1T rebuild kit comes with stronger components?

Ultimately, I'm looking to build a heavy duty engine.

Any other recommendations w.r.t rebuild kits on the market are welcome.

I will add that I already have a 4BD1 engine in my possession otherwise I'd go with a 4BD1T variant.

Thanks Joe

How many kms on yours, I had 320000 on mine and pulled the mains off and the shells looked great. Unless you have low oil pressure or blow by gas or low compression leave it alone. I would run the standard gasket kit if you do rebuild. The engines are crazy strong already.

Sent from my iPhone using Forum Runner

Thanks.

I was under the impression that components would be strengthen to accommodate higher internal loads/ egts.

Up around 450K now. Turbo on at about 400K. Haven't checked oil pressure but pressurising crankcase leading to oil coming up and out of oil dipstick and some blue in exhaust smoke under load, other than that it runs well.

No need IMO to upgrade at all, the standard rebuild kit to suit later engines with Alfin turbo spec pistons will be more than enough. My late (1988) engine has been turboed since 420K, it has now almost 600K. No noticeable change in oil use (Almost nil) and power is still up there

It breathes the same as when it was first installed 8 years ago.

I don't intend on touching it for some time yet.

JC

Originally Posted by 110Landy86

Thanks.

I was under the impression that components would be strengthen to accommodate higher internal loads/ egts.

In regards to this statement the alfin pistons as already mentioned will help but goodness knows how much...as you would know the only thing that is inside there is a sleeve , rings and piston all of which are pretty much the same apart from the alfin pistons that may allow higher egt's for a tad longer.
My motors an 85 model so asuming no alfin pistons and it sees stupid temps with no problems yet...

Hi

I am looking at converting my 4BD1 to turbo, and going through the logistics, I assume that I have to ditch the current air-con and retrofit one from a later defender, but I'm grappling with the issue of an intercooler or not. Any experience out there on this - I will keep air-con so space near the radiator may be an issue

cheers Smithyz1

Originally Posted by Smithyz1

Hi

I am looking at converting my 4BD1 to turbo, and going through the logistics, I assume that I have to ditch the current air-con and retrofit one from a later defender, but I'm grappling with the issue of an intercooler or not. Any experience out there on this - I will keep air-con so space near the radiator may be an issue

cheers Smithyz1

As boost pressure is increased from about 12 psi up, it becomes more advantages to intercool.

With a bit of work you can have aircon plus intercooler. JustinC build thread shows what can be achieved - sorry I don't have a link, but I think the thread may be called "the new tourer" or similar.