Lets see where to start =\

First off a few of my rockers were a little out of adjustment. but... Car was running good. Was out on the highway one day, it was raining.

Some guy in a riced hyundai (tiburon maybe, doesnt really matter) started pacing me, then blocking me in behind other cars, etc. He wouldnt let me pass for a good 15 minutes. I got pretty pissed off, my anger got the better of me. He gave me an opening barely, so i downshifted and shot past him.

For some reason I left the car in drive and held it at 5000 rpms instead of shifting. I easily broke 105 but never passed 5000 rpms. But i probably held 5k for at least 10 seconds.

Ok so now the problems start. Later that day when i started the car again, after it had cooled off etc, it was running a little rough. Over the next few days it got worse and worse, to the point where it almost felt like i was on 7 cyl.

Me and a buddy adjusted the rockers, one of them was really out, that helped a little. Then i changed the plugs and it seemed to be fine. Almost fine, if i took it up to 5k under load it would backfire (2 or 3 small ones) right as i shifted.

So then i went away for the weekend, and when i started the car for work on monday it was running like crap again. Once again feels like almost 7 cyl but not quite. Now today im almost 100% sure its only running on 7 cyl. If i rev over 3k it gets really rough, bad power loss etc.

So relevant info. New cap rotor and coil (accel supercoil 48k i think) 8mm wires, accel shorty plugs gapped to .045.

All the plugs i pulled out look the same, dark black buildup around the outer edge and threads, the tip and the ground look fine.

Suggestions I have gotten so far are, hotter plug, larger gap, change carb jets, and possibly blown piston ring.

So i guess im just asking for ideas, since this has gotten to the point that im so angry about it i cant spend more than 30 minutes playing with it.

 

Look real close at all the valve springs and the rocker studs first.

Then look at all the valves, make sure they're all moving about the same amount.

Then a compression test.

I'd suspect a broken valve spring or pulled stud most likely; a wiped cam lobe next; or a blown head gasket, least likely.

 

pushrods are straight
no broken rockers
no broken springs
what i can see of the valves also fine
the studs are screw in

however, the exhaust rocker on cylinder 1 (front on driver side) had about half the range of motion as any of the other rockers. It felt really loose, but when I tightened it, it didnt seem to help.

I will do a compression test on that cyl tommorow, and another for comparison.

 

Sounds like you wiped a cam lobe.
How did you "look" at the valves? Do you have a bore scope?
Do a compression check.

 

by look at the valves i mean i checked what i could see of the valve stems... sorry i typed that in a rush, i should have been clearer

 

The valve stem wouldn't be the problem.
The problem would be the head if a valve floated for a split second and got whacked by a piston.
As far as one rocker not lifting as much as the others sounds like a rounded off lobe and probably something that happened some time back only to be found now.
As far as all the plugs now running black, a backfire may have blown the power valve in the carb causing it to stay rich.

 

Sounds like a wiped cam lobe to me.... not enough valve sprimg probably; put too much stress on the lobe running at that high RPM for that long. Especially if that rocker nut has to be further down the stud than others to take up the lash.

 

welll that really sucks... the place that I bought the heads said the springs were good to 0.600 lift and im not close to that.

i guess that explains the backfire then too

 

Ok, since i was going to get rid of the car anyway pretty soon.... is there anything I can do to partially fix this. Will properly adjusting the rocker help or hurt? (it is still rather loose now)

One person I know suggested a longer pushrod, just for that valve.

 

Have you perfrmed a ppower balance test to determine what cylinder(s) is causing the problem?