302 CROSSRAM ENGINE

[69 JL-8]

WHEN I RUN THIS ENGINE, THE PASS. SIDE HEADER GETS VERY HOT, ESPECIALLY AT IDLE. THE CROSSRAM SETUP IS ORIGINAL WITH THE #4295 CARBS AND A #140 CAM. I WOULD APPRECIATE ANY TUNING TIPS THAT YOU MAY OFFER. GREATLY APPRECIATED, JEFF

[njsteve]

Do you have the plug wires installed wrong? I once accidentally swapped #5 and #7 on the distributor on a small block Chevy. Because they were so close in the firing order, (1-8-4-3-6-5-7-2) there wasn't much of a noticeable misfire in the engine, but one header pipe (they were painted white at the time) glowed green from the extreme heat.

Or is one side of the exhaust blocked? Internally blown muffler bocking output?

[Salvatore]

sounds lean to me. A vacuum leak maybe? Timing?

[juliosz]

If you're low on vacuum at idle, lower than your power valve is rated, then you maybe dumping fuel at idle from the carb feeding that side. I've had very hot exhaust from an extremely rich condition as well. Good luck

Paul

[69 JL-8]

THE PLUG WIRES FOR THE T. I. IGNITION ARE INSTALLED CORRECTLY. WE RECENTLY INSTALLED A NEW CHAMBERED EXHAUST SYSTEM. THANKS, JEFF

[PxTx]

If you swap the carbs from side to side, doe the problem follow the carb?

[sYc]

Chevys with a factory intake will not heat the exhuast tubes the same at idle or low RPM, as they do not flow equal amounts of fuel. And I would inagine a crossram would be one of the worst offenders.

That is why all books say "read the plugs" after running wide open.

[edcar70]

Jeff, I love the L-78. Do you have a 4-gas. It would help to determine if it is lean or rich. ed

[VintageMusclecar]

-Check the gasket on the manifold lid to make sure it isn't out of place or torn

-PCV hooked up?--if not, is the boss on the manifold plugged?

-Do the idle trim screws on the DS carb have any effect?

-Are the carbs synchronized to each other?

-Are the carbs originals or service? Are they rebuilt/restored?

[Jeff H]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: edcar70</div><div class="ubbcode-body">Jeff, I love the L-78. Do you have a 4-gas. It would help to determine if it is lean or rich. ed </div></div>

Ed, that's a different Jeff with a JL8 crossram car, who would've figured! [img]<<GRAEMLIN_URL>>/dunno.gif[/img] I still miss the L78 car but I need to get my JL8 car finished so no regrets.

Anyway, Jeff, give Kerry a shout over at Camaros.net, I responded to your post there, but he's been running the crossram setup for a few years on his 69 Z and the jetting is staggered from what I remember. He may be on here as well as Green Z but that is his user name over there.