Offroad-Express

I recently had my diesel pump serviced in chch (something to do with a ball bearing that can drop and break stuff) and they guy mentioned that the fuel has been cranked up a bit. Now the truck is still running factory boost.
Im pretty hazy on how the boost system works in a diesel (more fuel gives more power and boost cools ??) My motor has around 280000ks on it so i am cautious on putting more boost through a old motor. Would bringing the boost up to match fuel do harm or am i better to turn the fuel down to factory level?

When towing the rally car the truck does overheat a bit going up hills would this be because of too much fuel also?

Cheers
Nick

Nick555 wrote:I recently had my diesel pump serviced in chch (something to do with a ball bearing that can drop and break stuff) and they guy mentioned that the fuel has been cranked up a bit. Now the truck is still running factory boost.
Im pretty hazy on how the boost system works in a diesel (more fuel gives more power and boost cools ??) My motor has around 280000ks on it so i am cautious on putting more boost through a old motor. Would bringing the boost up to match fuel do harm or am i better to turn the fuel down to factory level?

When towing the rally car the truck does overheat a bit going up hills would this be because of too much fuel also?

Cheers
Nick

If it is one of the older 4.2s I would be wary about increasing boost as the big end bearings are a bit small and prone to wear.

Why did they increase the fuel ?

Cheers Richard

Its a 94. Fuel was turned up by previous owner. Not sure why

it depends a lot on what the fueling does when there is more boost. some vechiles will lower the fuel when runnng high boost, others won't.

if the vechile wasn't smoking before i doubt the fuel was wound up unless the boost has been wound up to match.

how much boost?

Depends on 'whats been turned up' on that pump.

I turned up quite a few adjustments on my 1HDT on factory boost and noticed a lot of difference, coming on boost earlier and more responsive up in the rev range.

Before I up the boost I'd like a 3" exhaust and intercooler to make the most of it.

cool thanks guys

A good peice of preventitive maintanence on these engines is to drop the pants off them and replace the bigend bearings which is a quick and relatively cheap job especially if running more fuel and boost... It will greatly extend the life of an otherwise excellent engine If your engine is getting up around the 300,00km mark

toyotas are always good for more boost if you have the ct26 toyota turbo they are good for 10psi think they run around 5psi factory not sure on the fueling with that motor tho.definitly do the big ends that way you know yourself that they are done,and use good oil and change it often i do mine every 3000kms bit overkill but that way you know its always real good

i ran 18psi on my intercooled 13bt, did so for the 3 years until i sold it.. no issues. shit you could get some mean turbo whistle back through the intake.. the vehicle had 3 inch with one bullet muffler and dedicated wastegate pipe, not back fed into exhaust. if that makes any difference..

callum007 wrote:i ran 18psi on my intercooled 13bt, did so for the 3 years until i sold it.. no issues. shit you could get some mean turbo whistle back through the intake.. the vehicle had 3 inch with one bullet muffler and dedicated wastegate pipe, not back fed into exhaust. if that makes any difference..

I think you guys are missing the point. A 13bt is a truck motor and built like a brick shithouse.

The motor in question is a 4.2 and the big ends are small and are reknown for being replaced under 100ks so to over boost a motor like that is asking for trouble .The later 4.2s with the 24valves are a different kettle of fish and are strong.

cheers Richard

o. i hadnt heard that about the early 4.2's... its a toyota.. it'll be fine.