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Discussion Starter #1
A while back I had the Injection system rebuilt. The car started and idled ok but seemed to run rich and was down on power. Recently, we looked at the system and found two things, first the throttle linkage was not allowing the butterflys to fully open and the injection timing was off one cog. Reset the engine and I regained the missing power. Still starts and idles fine and at low speed runs good - but when rpms begin to rise I lose the back two cyls. They are getting spark but not enough fuel. The plugs come out dry after running at speed. Have checked fuel flow at low speed through the injectors and it seems ok.- and fuel injection piping from the pump to the injector and they seem fine. I don't have the equipment to check high speed flow.
I have the feeling I'm missing something very simple.
Any ideas,
Thanks,
Dale
 

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Hi Dale.

Have you checked the fuel pump pressure? The flow to the pump might only be enough flow/pressure to supply the front cylinders at higher speeds.

Regards
Phil.
 

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Discussion Starter #3
Thanks Phil,
Maybe I've made a very bad assumption that the fuel pressure warning light would come on with low fuel pressure. All the filters are new and clean - as were the ones I replaced. Pumps seem to be operating normally. Guess a flow test might be the next item. I will check this after checking an item Wes Ingram mentioned that the pump timing might be 180 degrees off - the alignment not set with #1 Exhaust valve open but closed.
Thanks,
Dale
 

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pump timing

Here is what Bruce Taylor was kind enough to confirm when I was re-timing my pump:

"The correct position to use is when the I mark is centred in the inspection hole with the piston of cylinder 1 approaching TDC of the induction stroke.

TDC of the induction stroke of cylinder 1 is when the piston of that cylinder is at the highest point of its travel and both the inlet and exhaust valves are open. (It is easily distinguished from TDC of the power stroke because then both valves are closed).

As you have observed, at the injection time the exhaust valve is open and the inlet valve has not yet opened (but it does so shortly afterwards).

There is a valve timing diagram on page 97 in the book."

When my pump was 180 degrees out, the car ran but not as smoothly. (I have a '71 non-S motor, btw.)

--Charlie
 

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Discussion Starter #5
Thanks for the Help

Thanks for all the suggestions. It turned out to be that when the pump was reinstalled it was timed 180 degrees out of whack. Thanks to all for your help and to Wes Ingram for taking my call.
Dale
 
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