How does lower compression affect performance?

[dave friday]

Hi all,I just advanced the timing a bit more 3 or 4 pencill lines..no marbles on a plate sound and no increase in performance!
Any ideas?
Ta.

[8v-of-fury]

ITs not gonna be night and day difference because you were probably close enough to begin with 3 or 4 pencil lines back.

Now you are still within a good spec for your pump and injectors, and it still runs good. I have found that the furthest advance you can run without getting marbles all over is the best setting for all around performance and starting.

[dave friday]

Just to add a bit more info..before replacing the turbo and 2 injectors I could get up my test hill in 3rd gear, now I have to drop down to 2nd !!

[ORCoaster]

Time to time it backwards to you initial point or maybe back 2 pencil width lines.  You have gone to far forward and are hurting yourself.  The injection is coming in so soon that the piston is still on the compression stroke and being blown back down with the advanced fuel delivery.  At least that is my assessment of the performance.  Anytime you need to drop a gear it is over the sweet spot.

[dave friday]

Thanks,will do.

[dave friday]

Just checked the timing,1.20!! wound it back to 1.00.
The "smoke" screw was wound out a bit [still has the security clip on it]so i wound it back in again.
Seems to have improved the performance a bit but not to the pre turbo/2 injectors swap[ old turbo was leaking oil into the inlet,old injectors were out of spec]
I going to get the new injectors checked!!
Thanks for the advice.

[8v-of-fury]

So there is a little manipulation you can do for fine tuning these bad boys. You turn you throttle lever in relation to the throttle  shaft it turns, either CW or CCW I cannot recall at this moment. By doing this you are allowing the internal throttle to be slacked so to speak. You then crank in the fuel screw and now the fuel collar on the plunger moves further down injecting more fuel You will have to redo all the pump settings but there is quite the performance to be had.

[ORCoaster]

I think it is CCW. one spline at a time maybe no more than one.  Libby knows for sure.  He is the one that tells us all this good S....