okay i have a 1990gt and everything is brand new it is a 306 with kieth black pistins,ecam,trickflow aluminum heads,trickflow 1.6 roller rockers,holley upper and lower intake,holley 70mm throttle body,bbk 70mm egr spacer,bbk cold air intake,24lb injectors,holley 190gph fuel pump,bbk adjustable regulator with liquid filled gauge,granttelli 24lb mass air meter,msd pro billet distributor, and its like i cant get the timing right but i know it is i set the timing mark on 0 on the compression stroke and put it on number one and it wont idle it will run but it skips and pops when ugive it gas and yes the timing chain is perfect check it twice i really dontknow much about adjusting the valves but i read the book and did everything it said to do and it still wont run someone help me get it running before my wife kills me thanx
some thing wrong
- Thread starter jake1990gt
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I would check the dist next. make sure that all the wires are going to the right cylinders and that the cap is on tight. it sounds to me like they are trying to fire in the wrong order. double check all your dist connections and wire placements.
LiquidGT
Member
When I did my engine swap I had the firing order wrong thanks to Chiltons. Like stykthyn said it sounds like an ignition problem.
Fuel system clogged?
Timing set BTDC?
Spout connector?
Just throwing out Ideas.
Fuel system clogged?
Timing set BTDC?
Spout connector?
Just throwing out Ideas.
the reliefs should be pointing up and they should be fine with your heads, all that aside it should not make your car backfire and miss, you would hear the sounds of pistons slapping valvles.what you have is a spark/timing issue.
I can almost guarantee that if you set your timing with a Chiltons that it is wrong.
MSD is also notorious from making garbage. Try to rotate your dist with the car running and see if the car runs better, also if you have the stock distributor plug it back in and see if your problem continues.
I can almost guarantee that if you set your timing with a Chiltons that it is wrong.
MSD is also notorious from making garbage. Try to rotate your dist with the car running and see if the car runs better, also if you have the stock distributor plug it back in and see if your problem continues.
PUNISHER RACING
Active Member
PUNISHER RACING
Active Member
holy crap that has to suck. if he had bent valves wouldnt his car be smoking real bad??
PUNISHER RACING
Active Member
no it would idle like it had the worlds biggest vaccuum leak and backfire upon hitting the throttle
PUNISHER RACING
Active Member
wouldnt the pushrods bend before the valves?I have bent p.rods before but never a valve. perhaps I have been lucky????
PUNISHER RACING
Active Member
It does not take much to bend either when you have the clearance you bend the push rods when you don't it is just enough to knock the valve around a little and cause a bad leak in that cylinder. That causes a rough idle and all kind of backfiring like stated. Wonder where he is?
Don't be surprised if a couple of your KB pistons are broken around the valve relief. My buddy's 347 busted 3 of them for no apparent reason with only 2k miles on them.
PUNISHER RACING
Active Member
Do a compression test first to verify that you have bent valves. A bent valve will not seat and seal properly, resulting in low compression.
Only use a compression tester with a screw in adapter for the spark plug hole. The other type leaks too much to get an accurate reading. Your local auto parts store may have a compression tester to rent. If you do mechanic work on your own car on a regular basis, it would be a good tool to add to your collection.
With the engine warmed up, remove all spark plugs and prop the throttle wide open, crank the engine until it the gage reading stops increasing. On a cold engine, it will be hard to tell what's good & what's not. Some of the recent posts have numbers ranging from 140-170 PSI. If the compression is low, squirt some oil in the cylinder and do it again – if it comes up, the rings are worn. There should be no more than 10% difference between cylinders. Use a blow down leak test (puts compressed air inside cylinders) on cylinders that have more than 10% difference.
I generally use a big screwdriver handle stuck in the TB between the butterfly and the TB to prop the throttle open. The plastic is soft enough that it won't damage anything and won't get sucked down the intake either.
A battery charger (not the trickle type) is a good thing to have if you haven't driven the car lately or if you have any doubts about the battery's health. Connect it up while you are cranking the engine and it will help keep the starter cranking at a consistent speed from the first cylinder tested to the last cylinder.
Only use a compression tester with a screw in adapter for the spark plug hole. The other type leaks too much to get an accurate reading. Your local auto parts store may have a compression tester to rent. If you do mechanic work on your own car on a regular basis, it would be a good tool to add to your collection.
With the engine warmed up, remove all spark plugs and prop the throttle wide open, crank the engine until it the gage reading stops increasing. On a cold engine, it will be hard to tell what's good & what's not. Some of the recent posts have numbers ranging from 140-170 PSI. If the compression is low, squirt some oil in the cylinder and do it again – if it comes up, the rings are worn. There should be no more than 10% difference between cylinders. Use a blow down leak test (puts compressed air inside cylinders) on cylinders that have more than 10% difference.
I generally use a big screwdriver handle stuck in the TB between the butterfly and the TB to prop the throttle open. The plastic is soft enough that it won't damage anything and won't get sucked down the intake either.
A battery charger (not the trickle type) is a good thing to have if you haven't driven the car lately or if you have any doubts about the battery's health. Connect it up while you are cranking the engine and it will help keep the starter cranking at a consistent speed from the first cylinder tested to the last cylinder.
PUNISHER RACING
Active Member
I personally would remove all the rocker arms and check pushrods first and foremost, then with the valves all closed up remove plugs and place an air chuck in the cylinders one at a time to listen to each cylinder. If you got a bent valves you will hear the air traveling out the exhaust or up the intake. The only reason I say this is running the engine anymore now will only cause further damage to it. Just my 2 cents!
Do you know for sure he has 281's and not 311's? It doesn't say in his description. If you are just assuming he has bent valves, that's no good. The E-cam is not all that radical and might not be a problem at all.
Did you advance the timing at all to see if it improved? Did you put the wires on the cap in a counter clockwise rotation of 1-3-7-2-6-5-4-8 ??
PUNISHER RACING
Active Member
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