Thread: Turbo Isuzu Questions

Valves, yes. They run a lot smoother when the clearances are all consistent.

Timing, there is a tradeoff between advanced and retarded. Best to experiment on your own setup and find the best spot. More advanced gives you more noise (more like a tractor), more kick and slower turbo spool. More retarded makes it a little soggier, quieter and spools the turbo a few hundred rpm sooner.

Dougal see how you found it takes longer to spool up when timing is advanced did it still each maximum boost as per usual ?

Yes still reached max boost, it just took a few hundred more rpm to do it.

This few hundred rpm might not matter for some, but for me it coincided with not having enough boost on a 4th gear pull up one particularly long hill (porters pass). Instead of cruising up at 70-80 in 4th (this hill has corners) I was doing 60 in 3rd and probably using more fuel as a result.

Basically too far advanced caused drivability issues for where and how I drive.

Summer pic of porters pass here:

Dougal. I assume that over time as the timing gears wear you would need to advance the timing very slightly to compensate??? (say every 500k km or so...)

Originally Posted by isuzurover

Dougal. I assume that over time as the timing gears wear you would need to advance the timing very slightly to compensate??? (say every 500k km or so...)

I'm sure. Anyone had to do it twice?

Auh I see the dreaded lag when power is needed quickly as I have stated before on my tdi advancing it made it spool up quicker and make the drivability much nicer that's why im finding your results interesting I know a old fella with a stage 1 (correct me if I'm wrong with saying stage 1) isuzu it has original engine and just went in for pump rebuild at 1.3million k's because he said it was getting sluggish haha

Originally Posted by Dougal

Yes still reached max boost, it just took a few hundred more rpm to do it.

This few hundred rpm might not matter for some, but for me it coincided with not having enough boost on a 4th gear pull up one particularly long hill (porters pass). Instead of cruising up at 70-80 in 4th (this hill has corners) I was doing 60 in 3rd and probably using more fuel as a result.

Basically too far advanced caused drivability issues for where and how I drive.

Summer pic of porters pass here:

Off topic, but I drove my FIL's Toyota Dyna based campervan up Porters last year. NA 3L engine from memory, foot flat to the floor with clouds of black smoke behind and revs dropped down to about 1400 in second before we made it to the top.
Thought I was going to have to drop it back to 1st
Isuzu turbo would have been very nice indeed....

Steve

Originally Posted by Dougal

Yes still reached max boost, it just took a few hundred more rpm to do it.

This few hundred rpm might not matter for some, but for me it coincided with not having enough boost on a 4th gear pull up one particularly long hill (porters pass). Instead of cruising up at 70-80 in 4th (this hill has corners) I was doing 60 in 3rd and probably using more fuel as a result.

Basically too far advanced caused drivability issues for where and how I drive.

Summer pic of porters pass here:

LOL MOT gave me a prezzie there once, i think it was $12 + $6 court costs. Kwaka H2. now that's back in the day, being hunted down by a ghost gray HQ