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BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

Well what started out as a seemingly simple problem (wasn't getting fuel to cylinder 4) has turned into a complete rebuild.

I have a warranty on the fuel dizzy so i got it rebuilt. The engine still wasn't firing strong on 3 and 4 even after checking and adjusting everything imaginable. So we figure that maybe I have a weak or broken valve spring. I take the head off and check em with a screwdriver. 3 and 4 have just as much if not more stiffness than 1 and 2. Well what the hell I figure, Ill go ahead and pull the head off and take it to the machine shop just to make sure. He tells me that there wasn't really anything wrong, he said he did a little work to 3 intakes and 1 exhaust, but the springs were fine. I had him go ahead and port and polish it while he had it.

Well before I got it back, I figured I'd go ahead and do a leak down test just to make sure. Went and ate lunch and came back like 2 hours later to find that 3 and 4 had leaked alittle but just barely. Cool. Well before I leave the shop for the day (around 8 or 9 pm) I fill the cylinder back up and figure I'll check again int he morning just to be sure before I put the head on. Next morning I find that cylinder 1 is full, 2 is bone dry, and 3 and 4 are half full. Eff me.

Pulled the block. Pulled the pistons out. Rings look fine. So IDK what the hell is going on. But the engine is going to be totally rebuilt. I picked up all the gaskets, bearing, and rings today.

At least now I know that fuel isnt the problem. Neither is spark. And this weekend, I can mark mechanical off this list.

One question I had though. I figure while I got the block out, I may as well get it decked 1 mm to bring the CR up to around 10:1.

Question is, will my tensioner be able to handle it or should I pick a bigger one up or a smaller belt up? If one of the latter, any suggestions for donors cars that will work?

I did a search and didnt find a whole lot, but I seem to remember somebody posting that a rabbit tensioner would work?
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1980 924 NA
1982 931

Scorpio · Posted: Tue Apr 21, 2009 11:47 am Post subject:

Have you done an injector flow test? fuel dizzy may be rebuilt but if injectors are clogged then wont flow fuel..just a thought
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1979 NA
MS1..EFI..
GARRETT T25 TURBO
BILSTEIN SHOCKS
GT BASED CUSTOM BODYKIT

Brisbane , Australia
Think mean think fast
all youll see is
my Porsches Arse!!!

huckster · Joined: 22 Dec 2006 Posts: 115 Location: Burnaby B.C.

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

injectors are brand new.
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1980 924 NA
1982 931

Scorpio · Posted: Tue Apr 21, 2009 5:42 pm Post subject:

Rich H · Posted: Tue Apr 21, 2009 5:58 pm Post subject:

I got a random tensionner off an Audi 100 that is slightly bigger and offset more
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1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

thanks rich. The injectors are fine, they got a simply beautiful pattern and all 4 lines have been pressure tested.
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1980 924 NA
1982 931