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Discussion Starter #1
ok here is the deal just installed my new 347 ive checked the timing about 10 times (finger on the #1 piston hole felt compression turned the harmonic balancer to 0 degrees installed the distributor rotor touching the #1 plug wire) im getting fuel (because i can smell it and my fuel pressure is showing 40 as soon as i turn the key over) im getting spark because i checked. it acts like itll catch on 1 cylinder like it wants to start but really wont do anything unless i put the accelerater petal to the floor then it starts firing on mulitple cylinders but wont start. i was thinking since the lifters are hydraulic maybe they pumped up and now my rocker adjustment is off killing my compression? need answers fast have to drive this bad boy to work in 5 days. o ya and its strait headers havent gone to the exhaust shop yet
 

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If the engine won't start, you haven't checked timing. If you're getting fuel and spark (and you're plug wires are in the proper order), I'd say you're 180 out on the distributor. Get that number 1 cylinder on compression stroke and stab the dizzy so the rotor is pointing to number 1.
 

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Discussion Starter #5
i just bought a compression tester and im only getting 60 psi on all cylinders pretty consistant but i dont think its sapose to be that low
 

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Discussion Starter #6
i turned it 180 and nothing doesnt even act like it wants to run
 

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Discussion Starter #7
ok i just turned the dizzy the way i had it i got it to start but i have to feather the throttle to keep it running and it wont stay running for long. but damn if she aint loud with strait headers in an ally
 

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Sounds like mayb pushrods to long when u torqed rockers down did ur valves open a little stock rods probably wont work and 60psi no good
 

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Discussion Starter #9
well when i was setting the timing i took the valve covers off to make sure i had it on the compression stroke and there is no tention on the rockers you think they would be hard to move if they were applying pressure to the valves i could also move the pushrods with my fingers
 

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Discussion Starter #10
i didnt mention that the maf was calibrated for a 1993 cobra i dont know the difference but maybe it could do somthing the car will stay runnning if i keep it about 1500
 

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Discussion Starter #11
and its a pro-m maf calibrated for 30 lbs injectors which i have in the car
 

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60 psi sucks dude. You did something wrong. Redo the lifter preload.... Better yet tell how you adjusted the rockers.......
 

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Discussion Starter #14
i adjusted them by firing order twisting the pushrods untill i felt resistance tighted the rockers 3/4 turn and locked em down with the allen screw. if i totally loosened the rockers and did the compression check would that eliminate rocker adjustment?
 

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Granted the twisting method is all over the internet. It is greatly one of the worse methods ever. With todays oils and so forth, you can easily twist the pushrod with a ton of preload on the lifters. If the engine hasn't been primed when this is done, you could easily take have the lifter travel before notice any real resistance. Resistance is a relative term. My resistance may be a lot more than your resistance. Or less! Then you go another 1/2 and you've probably came close to if not bottoming out the lifter. If its primed with oil, the valve opens instead.

You are going to have to redo the preload on the lifters. This time just move the pushrod up and down while you tighten on the adjuster nut. Once the movement has quit, you are at 0 lash/preload. Then go 1/2 turn and set the set screw. Then go to the next cylinder.
 

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Discussion Starter #16
thanks for the info i will do that tomorrow i drove it today and the clutch was really jerky. and it stalls anything under 1000 rpm but it sounds like a monster but i will def re adjust my rockers
 

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Discussion Starter #17
well pulled the rockers completely off the #1 piston did the compression test and the same thing 60psi so that would mean the valves arnt seating properly correct, and that would mean the heads have to come back off and go to the machine shop? fml
 

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where the heads new or used when you installed them? also if your getting 60psi on every cylinder even without the rockers installed im not sure it would be an issue with the heads. did you build the bottom end yourself or did you have it built? i only ask because if the ring end gaps arent staggered properly on the piston that can cause some loss of compression as well.
 

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well pulled the rockers completely off the #1 piston did the compression test and the same thing 60psi so that would mean the valves arnt seating properly correct, and that would mean the heads have to come back off and go to the machine shop? fml
have you only checked one cylinder with the rockers off? i would check a few others on each bank and see if the results are the same.
 

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Discussion Starter #20
no i had the bottom end build by a machine shop i had the heads decked but no valve job. i just relized if the rockers are off it cant pull air to make compression so im going to set the rockers back on. and try it again if its still low ill put a little oil in the cylinder to see if its the piston rings if it doesnt go up its probably the the valves i would think
 
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