Thread: 454 Nova

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Ran my Nova today it has a 72 Mark IV 454 in it .Edelbrock torquer 2 intake Holley 3310 vac. sec. carb. Header's around 10.5-1 comp.Not sure of cam but has a lope to it.Advanced my timing to 14 degrees init. ,seems to run a little smoother. It still has a shutter when it is idling , also the timing line moves a little at idle. Could this be in the ignition? It has a H.E.I. with a accel super coil. When cruising at around 1500-2000 the exhaust backfires a little . When you get on it the engine really run's strong. Any help would be appreciated.

Congrats, feel good, doesn't it?? Sounds like you've got most of it running good. The timing mark moving around a little isnt that uncommon, what does it do when you rev it up a little and hold it steady?? Does it stay in place then? If so, it's OK. It could be the spark plug wires. Or if the dist. is worn a lot, it could be a little shaky, but I doubt it's the distributor. Make sure the rotor is in right and secure. When you get on it, you say it runs strong....but as the rpm's are increasing, do you still get the popping in the exhaust, or is it gone then?? It could be a carb adjustment causing it also. If it's a little rich, it will pop in the exhaust. Is there black smoke when it's running, or when you get on it? Dont sweat the small stuff, you will fine tune out these little quirks soon enough.

Just got new 8.8 accel wires , cap and rotor looked o.k.. Holley is new 70 jets in front 75 metering plate in rear.The car has not been on the road in 10 years . Trying to work out the bugs. Could my single plane giving me the backfiring,or the velocity stack? Once I throttle up the 454eally want's to go, no backfiring . I want to be able to cruise with it though . I am thinking of a Edelbrock Performer R.P.M. Air Gap. ,also a 14 " K-N air cleaner . Do you think this will help?

Very well could be the intake....I ran a single plane, a Team G, a couple years ago...Now that you mention it, I had a popping sound at cruize speed too....I know everything else was OK. I run an RPM Air Gap intake now, and no more popping sound. Maybe it's just that. The single plane is made for higher RPM operation, and the air/fuel mixture distribution at lower flow rates is uneven cause it's being pulled from a commom plenum (big area) by all eight intake runners. When you get on it, it smooths out like it should. If you have the ignition covered, and the carb, it cant be too much else. If it hasnt been run in 10 years, maybe just some miles on the engine will help smooth things out too. Enjoy it!! My engine is still in the shop being bored and decked, Im looking at another 3 weeks at least before my 496 is done. I cant wait, spring is here.

Thanks for all the advice. Going to check the dist spring's today . I only have a regular timing light , but the motor does advance when I hook the vacuum hose back up.It also advances when you rev the motor.Not sure of total advance though.Good luck with your 496 1JohnnyO