Doom86

I installed headers over the weekend and replaced my busted water pump. I also removed the A/C and smog pump and capped off all places where vaccume lines were removed from the partial smog removal.

The first time i took the car out it was accelerating awesome, it was like a different car. We drove around for probably 20 or so minutes with no problems. The exhaust is unhooked at the Y-pipe.

After letting it sit for 20-30 minutes and driving agian under WOT it would "sputter" while accelerating, the tac would jitter up insted of a smooth transition. At half (or so) throttle its fine and actually pulls harder then WOT. It doesnt sputter while in neutral, but seems to in all gears.

Things to note; while looking around the motor i noticed that one of the spark plug wires had been hitting on one of the primaries of the headers and melted, it was touching the header while driving. I'm going to re-harness it so its not touching once it stops raining.

The 02 sensor's wire had to be spliced to lengthen it because it was to short. It looks fine but i dont know if it could have messed with it somehow.

The Air-valve tension on the carb is pretty tight because i was getting a bad bog a few months ago and it cured it. I was thinking its possibly to tight now since the engines flow potenial has increased.

Thanks for any help

AM Racer

Sounds like the plug wire's cooked.
There's not enough load in neutral to get the misfire

Doom86

Many thanks, AM racer, i didnt want to go throwing money at my car to fix it with-out knowing for sure. I'll get some new wires tonight, i was going to get some anyhow so i can "kill two birds with one stone", hopefully.

Doom86

I replaced the wires and its still doing it. At half throttle it is great, but at full its terrible.

Would it help trouble-shoot if i got an audio or video of it doing it?

This is driving me nuts someone help a brother out.. I got to taste some good power from my car in 4 years for only 20 minutes.

Could it be my TPS sensor causing this??
i know its off but it never done anything like this before i put the headers on so i didnt think it would be the problem, but what do i know? it only goes to 2.7 volts at WOT.

AM Racer

It didn't do it before the headers, then any chance you dinged a plug porcelain with the header flange?
Fire it up in the dark and look around the plugs for any flashing. Sometimes a little water helps.

Doom86

This has been fixed finnally. I got some time to play with my car yesterday and found that it was leaking fuel from where the filter/ fuel line go into the carb. There was also a vaccume (how ever the hell you spell it) leak where i removed the gas fume can, the rubber line-cap was real loose when i checked it.

After inspecting and tightening the fuel line and hooking the fume can back up its been running solid since. I think the fuel preasure was dropping to low, there a noticalbe leak even at idle and fuel on the intake manifold.

This thing really comes alive between 3000-4800 rpms now.

Ive read that adding headers can move the max HP up to around 4800 rpm from a stock LG4. Last night was the first time this cars ever seen just under 5000 RPM, it still seems to be pulling hard then (i didnt go over 5k). But i wanted to ask something about the sound. From just over 4000 to just below 5000 where i shifted the engine sound gets louder and very mean sounding (hard to explain), is this normal? or some kinda mechanical failure? To me it sounds like my friends LT1 camaro at high RPM's, but i want to be "safe".