[Hacksaw]

Year One Power Crate 350 with the Edelbrock E-Tech package, hyd roller, RPM air gap, Pro Systems XC built by Patrick, Dynatech Musclemaxx headers, older MSD Pro Billet, 6AL, Blaster II coil, Moroso Ultra 40 wires. The problem I'm having is it acts like there is a miss somewhere. This engine has about 250 miles on it, and the miss is getting worse. I changed plugs, and they looked like they came out of a fuel injected engine. Perfect color. Cleaned the cap, and rotor, made sure the pick up in Pro billet was clean, switched to another 6AL, rewired the 6AL straight to battery to make sure it was good. 14.7 VDC constant, readjusted the rockers, ran a compression test, 160psi across the board, checked all wires individual with a spark plug, has good fire, and it advances with engine speed, tried two different carbs, checked fuel pressure 7psi, checked all 8 primary tubes from cold with a thermal heat gun and 5 of 8 were ranging 400 degrees after 1 min of run time, and three were in the 250 to 290 range. Is there anyway the Pro billet could be causing an erratic spark issue? I'm at a total loss this far. Thanks for any information

[F-BIRD'88]

Install a ground wire from the engine to the firewall and to the car frame.

[hcompton]

Since you have so much invested in this engine combo. I think you will want to call year one and edelbrock. Since you will surely want them to warranty the engine if any issues come up. Best to get them involved eary. They probably have some good techs that can help get things worked out. Msd is also good on the phone they will run over all the needs for voltage and grounding and make sure your all set.

Like fbird said be sure the engine and msd box is properly grounded. I would check all the gorunds for loose or dirty connection. Make sure paint is not causeing the ground to fail under a load.

[Hacksaw]

I ran new #2 high grade electrolytic grade copper from back of engine to firewall where the factory ground was and used a good star washer, ran another ground using the same copper wire from chassis to block, with new battery cables from block to battery. 6AL is grounded direct to battery, constant is hooked directly to battery, ignition is ran with a new wire to the fuse box and all have 14.5 volts running under load. Fired car this morning and it has the same issues. At this point, having tested everything, I am almost 100% positive that the Pro Billet, which is the older 8555 unit, is the issue. It's te last piece of the puzzle in my opinion... I plan to contact ATK engines, they built the engine for Year One, tomorrow to find out what they think. Unless I can find another Pro Billet close by to try. Right now timing is at 16 degrees initial and 36 total with the black stop bushing, and I have the light silver springs in it. I had the blue springs in before and there was no change. Also took the Autolite plugs to .045 instead of the factory gap of .038

[ssimpala]

MSD usually requires a smaller, rather than larger, gap in the plugs. Probably not your problem, but maybe.

[hcompton]

Originally Posted by Hacksaw

I ran new #2 high grade electrolytic grade copper from back of engine to firewall where the factory ground was and used a good star washer, ran another ground using the same copper wire from chassis to block, with new battery cables from block to battery. 6AL is grounded direct to battery, constant is hooked directly to battery, ignition is ran with a new wire to the fuse box and all have 14.5 volts running under load. Fired car this morning and it has the same issues. At this point, having tested everything, I am almost 100% positive that the Pro Billet, which is the older 8555 unit, is the issue. It's te last piece of the puzzle in my opinion... I plan to contact ATK engines, they built the engine for Year One, tomorrow to find out what they think. Unless I can find another Pro Billet close by to try. Right now timing is at 16 degrees initial and 36 total with the black stop bushing, and I have the light silver springs in it. I had the blue springs in before and there was no change. Also took the Autolite plugs to .045 instead of the factory gap of .038

Sounds like you got everything grounded well.

Not a big fan of atk. I am suprised year one uses them.

Have you talked with msd. They are pretty good. As you can imagine a lot of ppl have issues with electronics. So they are used to going over the setup. Now they may run you thru a bunch of silly test you have already done but usally they can tell if its there product or someone elses.

[Hacksaw]

Headed to Tulsa in an hour or so to get another Pro billet, coil, and plug wires. I'll start with the coil, then wires, then pro billet. If none of this works, then I'm out of options!!!

[Hacksaw]

Originally Posted by ssimpala

MSD usually requires a smaller, rather than larger, gap in the plugs. Probably not your problem, but maybe.

The 6AL manual reads that .040-.045 for up to 10.5:1 compression

[vinniekq2]

check wires,especially where they may be close to headers.I would close plug gap/the wires can leak

[lmsport]

When does it miss?
Idle?
Cruise?
WOT?
Really clean and white plugs might indicate a generally lean condition causing a miss, especially under light cruise.

[Hacksaw]

Changed all ignition with no change. Engine missed at idle and during acceleration with the Pro Systems carb, and misses at partial throttle around 2000-2500 with the Edelbrock

[vinniekq2]

open hood(car running) turn of lights in shop,look for arcs around VCs or headers.Use your wifes plant mister to sprinkle wires. make sure wires are all separated.
have you adjusted the plug gap?

[Hacksaw]

Originally Posted by vinniekq2

open hood(car running) turn of lights in shop,look for arcs around VCs or headers.Use your wifes plant mister to sprinkle wires. make sure wires are all separated.
have you adjusted the plug gap?

Yes, new plugs are gapped .045, old plugs were .038 and no change. Installed a different set of new plug wires, Taylor 8mm, and no change. Wires are separated.

[lmsport]

Richen up the carb and see if the miss goes away. Distribution in the intake may be causing one cylinder to missfire at certain RPM.

[Hacksaw]

Originally Posted by lmsport

Richen up the carb and see if the miss goes away. Distribution in the intake may be causing one cylinder to missfire at certain RPM.

Changed carbs back to the Edelbrock and the problem went away. There is still a slight bogg in the Eddy, but it's because of the secondaries not opening soon enough. But at least this tells me that the Pro Systems carb has some trash or something going on there. It's very strange why it's running great now. Like I said, chasing a ghost!!!