maybe timing
12-07-2004, 10:07 PM
#1
maybe timing So i have a haynes manual all the problems I am having refers back to ignition timing. When doing a cam install does the engine have to be at top dead center on number one when removing the cam? So the cam shaft postion sensor is not screwed up. Cause i am having backfiring under 1/4 throttle. but when at idle you rev it up slowly and it will go out to 5000 rpms before sputtering. So could my ignition timing be off and could it be cause of the cam install? I know i need to get it tuned. I have fully ported heads a stock bottom end and a .591/.569 230/226 on a 112 cam f1. Sorry for the ?s We were messing with it earlier and thought about the cam shaft postion sensor and if there was a certain way to remove the cam so it doesnt mess up the ignition timing? thanks for any help
Last edited by flippincamaro; 12-07-2004 at 10:32 PM.
12-08-2004, 05:40 PM
#5
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So are you saying that it was not installed dot to dot originaly and you had to tear it down and re-align the cam? If so you probably have a bunch of bent valves now, and it is throwing everything out of wack. What are you symptoms?
12-08-2004, 06:04 PM
#6
well i had piston to valve contact. We tore it down got the head checked it was good the guy pulled the valves out checked them they were not bent some how. Here is my symptoms it revs great idles great. But when you drive it if you go more than 1/4 throttle it bogs pops and sputters and sounds like crap. In nuetral you can rev it but if you flat foot it it bogs when it hits about 4800rpms. Good oil pressure i know i need the computer tuned but people say that the tuning wont make that big of a diffrence. it pulls hard as hell for the split second when taking off. but like i said once apast 1/4 it bogs out. Not sure what the problem is some people say it could be the cam shaft sensor or the crank shaft sensor, map sensor, i dont have a scan plug cause i did a conversion and havent got one put into the harness yet. thanks for trying to figure it out also it is dot to dot now i have an adjustable timing chain set we advanced it the first time and got things out of whack that was what caused the ptv contact but that is fixed now.