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night
08-14-2002, 06:34 PM
i was just checking some on my car today after it sat for a year and #2 is dead. but thats not the annoying problem.


has anyone ever had their car run great accelerating and slowing down, but if you hold the throttle at a steady speed it stutters like crazy?
it idles great (considering #2 has 0 compression). never moves off 850. but beyond idle it will not hold a steady rpm.
when im driving it throws me around everywhere.

just thought id ask first. maybe an easy fix.
im not in the mood to work on this engine.


i do wonder if #2 was dead before though. cuz i never would have known if i wasnt checking for the other thing.
it would mean i ran that 15.9 on 3 cylinders....

PhydeauX
08-14-2002, 07:23 PM
I'd take a wild guess that you have some rust on one or more of your valves in #2 keeping them from fully closeing. That is odd that you have a good idle on 3 cyl, mine will barely even run, maybe the computer adjusts for it at idle.

andy

night
08-14-2002, 08:40 PM
ya, i was thinking either the rings are stuck, or the valve(s) are carboned open. everything else is good.
i tried to compression testers. 1 showed nothing, 1 went to 20. the injector is firing and clicking. spark is sufficient. so it has to be mechanical.

i can get the head off in 30 mins, its what i could find after that makes me hesitate. not to mention i dont wanna buy a gasket. but that is the only thing i need. hmmm.....

although if do pull it, im gonna shave like 30 or 40 thousanths off of it and get some damn power from it.
gonna drop the tank this weekend already so maybe ill go ahead and pull the damn thing off

PhydeauX
08-14-2002, 09:39 PM
Dump some oil down in there and check the compression again. If it goes up then its probalby the rings, stays down and its problaby the valve, head gaskets dont usualy go bad from sitting. Funstick mentioned to me that the a20 head's deck was already a bit thin and advised me aginst having it shaved. I did some calculations and shaveing off 40 thousanths should put the compression of a later a3 to 10.4:1. I'll agree with him that having material welded into the combustion chamber would be a better way to get compression, and as a bonus you get a little bit of quench too, something the a20a lacks.

andy

night
08-14-2002, 09:53 PM
ya i thought of squirtin some oil in there, but i ran out of time at work and it was to dark when i got home. either way, head has to come off.


10.4 sounds good to me :D.

its a noninterference engine. there should be plenty of room to mill the head. well... i say so anyway. i have checked broken belts by taking the cap off and spinning the engine over. never hit anything. not that i care much anyway. this engine wont be in there long.
although i may not wanna screw up this head. it does have that PYR PnP
isnt it like 1 degree per 10 thousands shaved ? ive never even messed with my gear.

Sean
08-14-2002, 11:35 PM
yeah at 40 thou yr belts gonna be about 2.5 degrees off. also shaving the head that much bad bad bad idea. been there done that. youd be better off having the combustion chamber welded up. the exhuast valve is offset so you can fill the blank area in. it almost works out like a SBC heart head the fast burn chamber. ive gotten good solid 10hp gains doing it. good shit really.

night
08-15-2002, 04:17 PM
i'll just run it on 3 cylinders til i get my engine built.
i have the gear, but it needs new bolts and im paranoid it will slip and leave me stranded somewhere.

i dont like welding heads. not to mention it costs more than just sending it off to be shaved