cam swap backfire?
cam swap backfire? hey everyone, this isnt ls1 related but i know theres a lot of knowledge floating around on these boards and pushrod engines tend to operate similarly from company to company so i figure someone can help me out. besides my t/a i have an '02 dakota 5.9 r/t. i just changed the cam in it recently. went from a 210/220 544/544 110lsa+4 to a 224/230 535/544 110lsa+4 comp cam. the lobes before were on the high energy/magnums while the new one has xtreme energy intakes and magnum exhaust lobes.
whats happening is that i am getting popping out of the exhaust. it happens lightly at idle and more severe if i goose the throttle in neutral. if i try to drive down the road i can barely go because it backfires a lot more. i confirmed that the cam is installed correctly and not off by a tooth. distributor is also installed correctly and spark plug wires are pretty new and attached to correct plugs. fuel synch is set where it should be too. what else can be wrong that is causing this? attached some videos of the issue. thanks guys. gonna be installing a cam in the t/a soon so hopefully whatever i did wrong here will be a learning experience.
http://www.myspace.com/video/rid/109243603
http://www.myspace.com/video/rid/109243678
http://www.myspace.com/video/rid/109243739
http://www.myspace.com/video/rid/109243787
whats happening is that i am getting popping out of the exhaust. it happens lightly at idle and more severe if i goose the throttle in neutral. if i try to drive down the road i can barely go because it backfires a lot more. i confirmed that the cam is installed correctly and not off by a tooth. distributor is also installed correctly and spark plug wires are pretty new and attached to correct plugs. fuel synch is set where it should be too. what else can be wrong that is causing this? attached some videos of the issue. thanks guys. gonna be installing a cam in the t/a soon so hopefully whatever i did wrong here will be a learning experience.
http://www.myspace.com/video/rid/109243603
http://www.myspace.com/video/rid/109243678
http://www.myspace.com/video/rid/109243739
http://www.myspace.com/video/rid/109243787
Can't see the bids on my phone but is it possible timing is off on. They dizzy? And I belive base timing is not adjustable on those and you have a cam position sensor in the dizzy. If not set properly via scan tool it would cause this. That's my guess. If I had a working laptop I could check all data but I don't. Hope this helps
yea base timing is all in the pcm. cam sensor is in the dist. only thing the dist does when you rotate it is change the fuel synch for when the injectors fire in relation to the spark plugs. i set that with a snap-on scanner though so i know its right and i checked visually and it looks like its where its supposed to be.
figured out the problem. last year when i installed my new MSD wires i waited till i had them all on before i put those little white lables on them and i switched up the #5 and #7 wire labels so the wires were on right but the labels werent so when i did the cam swap i went off my labels only and thats what caused the problem. now the truck runs awesome. cant drive it yet because of the snow but it doesnt backfire anymore
