A restricted engine, say a race engine that has to run the standard carb, are often built to have high compression. They can run a high manifold vacuum (maybe 6" at WOT) effectively reducing the compression when under full load. Cam timing also has a big bearing on cranking pressure.

At 250psi it would probably be an alcohol engine or a restricted engine?

Help is out GG, what sort of engine is it? My A12 only cranks 110psi. Flat tops with a big cam.

250psi , sounds like an engine built for economy. High compression ratio but with a mild cam? Or a race engine where the rules don't allow a change in cam?

Ill take the turbos if you still have them?? Ill give you a call, Cheers

Here is a dyno graph with a comparison to a worked L20 with twin DCOE's

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  Davids A15T Dyno Graph 001 resize 30%.jpg (131.63 KB)

I've had Ziggy's ute in the shed for the week. All the wiring and fuel system worked perfectly(Good work Zig!)apart from a stuffed SH module that I had supplied!. Just needed to put a pull up resistor(1K ohm)on the distributor hall sensor for the ECU to pick it up properly.
Once it was configured and running, it had a few trigger errors that had to be filtered out in the software. Then made a start on the tune. I had trouble with the idle as the injectors are very large(660cc)for the size of the engine. If I tried to reduce the injector pulse width to lean out the idle mixture, it would just fail to open them at all. I could have tried to lower the fuel pressure to fix it, but as the intake temps were getting up around 80 deg c at 12 Psi, Zig and I decided to switch to E85 to enable wider pulse widths at idle and help with the intake temps.

Yesterday the head was retensioned and valve clearances done.
We backed off the boost to 9 Psi and finished the tune today. Then the fun part.....The road test! Lucky me got to drive as Ziggy's leg is still out of action.

Zig supplied the turbo, its a brand new Garrett of a 2.4 diesel engine. I was a little skeptical at first but it proved to be a cracker. 5 Psi at 2500 gate fully open by 3000. It produces about 160Nm from 3200 to 5000rpm and 86Kw at 5800 and 11.5 Psi.....76Kw at 9Psi.

To put that into perspective, that's more torque and over a wider range than my 2.7Lts twin cam Hilux.

Well done. Very good idea. I like it a lot! Would save heaps of time as well.

+1... Taking the Z at this stage.

No room inside the shed, but plenty of room out!
Drums all round Zig. With the lack of options this this has, I'm probably lucky it's got brakes at all!

Good stuff Stu! Gees, that TB setup gets around! Its like a game of pass the parcel... someone turn off the music!

DD, You could be right about the vinyl floor post 1978. I still have to finish a bit around the shed before I can do anything to it. I might just leave it as it is, or maybe just a set of alloys and lowered slightly.
I still have the other ute with the missing rear tray to use as a project car.

The ute is pulling the chicks already, hey Flatto. Thanks for posting the link for this too!! It was only 5 mins drive from home.