brandon 455

I just installed new plugs and wires on my Cutlass. Somehow when I was putting them on I ended up developing a dead spot at cruising speed. I've checked my plugs and wires along with the distributor cap and rotor. What else could it be?

brddg

Crossfire? Route plug wires 5 & 7 in opposite directions around the distributor and see if that helps.

brandon 455

Okay ill give that a shot tomorrow. Could you explain how cross fire happens?

brddg

When cylinders that are next to each other fire in succession the spark energy can "jump" from one wire to the other and cause a misfire in that cylinder. I have heard that the cylinder pressure causes increased resistance in the plugwire but it's really a moot point if it gets fixed.

brandon 455

Okay that makes since

oldcutlass

Make sure all your wires are seated properly at the distributor and at the plugs. You also could have gotten/ or cracked a plug.

brandon 455

Well I tried my old plugs and wires and ity was still doing it which points me to the distributor.

oldcutlass

Was it doing it before you changed them the first time? Did you change anything else?

brandon 455

No it wasn't doing it before. They only other thing changed was the 2 front jets in my carb. I went from a 75 to 78 there.

oldcutlass

Try going back to what you had in there before.

brandon 455

Ill try and see what happens

brown7373

That's a pretty big jump in jet size unless you also installed bigger rods. It would make the mixture a lot richer at cruise and might cause the bog. The normal proceedure is to go to a bigger jet and a bigger rod. Virtually all primary rods have the same size tip, which means a bigger jet would make it richer at full throttle. But if you don't go to bigger rods, the mixture would also be much richer at cruise and part throttle, which is not usually a good thing. A richer mixture only helps if the engine needs a richer mixture. Too rich and you lose power and drivability.

brandon 455

Its not to rich it still is a little bit lean.