Thread: things to upgrade for high performance

May I ask who done the diesel gas system ?

Originally Posted by rovercare

When your manifold cracks you'll be spewing, not many have lots of luck with made manifolds

Pipe welding for pressure purposes sorts the sheep from the goats (so to speak) - I have done enough work for large chemical plants and when they have a shutdown they get the best welders from around Australia, then need to get others from other parts of the world. The best pipe welders seem to be Korean (their TIG technique is superior.

One thing that should be done is to block both ends, purge the inside with shielding gas, and run the gas continuously until the root run is finished.

Yes Rovercare , okay , I confess, I do suffer from boost envy

CHIEF. It was already fitted when I bought it. Done by Bolton 4WD in Eltham , Vic. Not necessarily a great job. The tank is a 25 litre capacity but never takes more than 14 litres. I think that is because it is under the driver's seat and the valve arrangement is at 45 degrees off horizontal , thereby affecting the fill capacity.

Isn't there a Turbo Isuzu / D Gas tuning expert somewhere in Sydney?

Originally Posted by Bush65

Pipe welding for pressure purposes sorts the sheep from the goats (so to speak) - I have done enough work for large chemical plants and when they have a shutdown they get the best welders from around Australia, then need to get others from other parts of the world. The best pipe welders seem to be Korean (their TIG technique is superior.

One thing that should be done is to block both ends, purge the inside with shielding gas, and run the gas continuously until the root run is finished.

Yes, but unfortunately little Asian welders, that love there job so much they make bets and have welding comps during their breaks are not all that easy to find some days

Just my experience with these manifolds, huge sustained heat from the diesel seems to warp them, either causing manifold leaks or cracks, ****ed a few off on td42 engines and replaced with standard cast jobby, after repairing then milling again a few times

I think it's a waste of effort for a single turbo, I don't think there will be much notable benefit on a 4bd1

Mmmm both have points here... I do have a few mates that do power station boiler tube welding and are Australian but then they have to get time to do it how John said...I'm beggining to think using my standard manifold will be easier to stick with at this stage then...

Originally Posted by c.h.i.e.f

Mmmm both have points here... I do have a few mates that do power station boiler tube welding and are Australian but then they have to get time to do it how John said...I'm beggining to think using my standard manifold will be easier to stick with at this stage then...

That's my thinking too. If you have to fit a turbo in a completely different location (as John is) or are chasing the last few % then a custom manifold may be worth the hassle.
I'm sticking with the factory Isuzu items.

I can't see the point in gas fumigation. Fit a turbo instead.

yep after looking at other factory manifolds the isuzu one (although i slightly different to yours) is about as good as your going to get before having to goto this extra trouble of a custom manifold...at this stage i will just have to compensate for the small loss with other methods

im yet to make a full decision on lpg fumigation as i have read some of your points on other forums about it...
although if the volume of lpg is to large it will pre detonate but if the quantity is reduced it will not...
i do have a mate that designed a diesel gas system over here in australia and his system then was copied by others even though his was one of the only properly certified system in australia..unfortunately once he started to progress further and further with designing a fully electronically controlled system others started to try and destroy the company and things got ugly...
only thing that i can suggest is if you have not tested it under load it will not give a true demonstration as most systems are progressive but im sure you have already tried...
but in the end i am yet fully convinced with lpg!!!
however i will post back in the future when i decided to give it a try.. in the mean time as you have said boost and fuel will achieve power so im staying with that
if anything i am more interested in giving water injection a try

Just finishing wiring a shed for dude who is a pressure welder offshore, I spyes a manifold he is making for his car, big single turbo LS1, looks nice, but I think petrols are more forgiving, as they dont sustain the temps, unless making power, none the less, no cast iron manifolds available to do the job he is after