So I've finally gotten the new to me roller 302 in and buttoned up. Can not for the life of me get it to run worth a Crap. Compression is around 135 per cylinder. Tried a known good carb and still runs like crap. Guess I got another dud on my hands.......smh Can only get it to fire and run with the timing really advanced. Idles around 1700 rpm and backfires through the exhaust. Can't get it to run at any other timing. Timing marks show around 30 degrees. Msd mechanical dizzy......performer rpm intake....gt40p heads.....ARP head studs......new water pump......etc etc etc. Put this motor in to replace the flat tappet 302 that ran lack luster. Only good thing is the near stock 351w in my dads maverick is reliable and makes enough power to be fun. Guess its time to pull the motor.....again...... So frustrating.
What is the engine out of? I understand some of the early roller cam truck 5.0 engines still used the standard 302 firing order.
sounds like the firing order is ok 13726548. im questioning the mechanical timing. has the ring on the balancer spun? are you using the correct timing pointer for the balancer? is the cam timing correct? was the cam degreed when installed? was an adjustable timing chain used and not set up properly?
They are ford racing pedastel 1.6 roller rockers torqued to spec. Supposidely motor came out of a running driving 90 stang with all the mods except the roller rockers that I put in. So could very well be cam timing when the trick flow cam was installed. Its a brand new adjustable timing pointer. When the motor was out I rolled it to tdc #1 and set the pointer so at max it might be 4 degrees off one way or the other.
well you dont have to pull the motor to check the timing chain. just the front end of the motor. thats where i would be looking.
I'll check that this weekend hopefully. I'm almost 100% dizzy is correct. Spun it over with #1 out until I felt compression then took it to tdc and stabbed the dizzy.
try the other firing order.... i had a problem where my motor is supposed to be HO firing order but the cam was standard 302 firing order (edelbrock rollin thunder). on these 302s the motor accepts both firing orders... its easy to try anyways if it doesn't work its not like you took the motor half way apart to find out.
I'm sure you'll find the problem - might be something simple - the engine sounds like it should be a real runner
