CoBRaKiLLnT/A

i was on my way home friday night around 3 am, and this damn eclipse will not stop messing w/ me. for about 3 miles he paced me getting on it every once in awhile. so finally i slowed down to about 55 and put er in 2nd and nailed it. killed him, but when i went to hit 4th.... i hit second . my car shakes like a b*tch now, and will drop to about 500 rpm @ idle sometimes when it is usually @ 900. i took it to autozone cause the SES light came on and started flashing, and they plugged it in. it read a misfire in cylinder 5. what else could cause a miss other that plug or wire???

CHRISPY

you had a mechanical overrev and kissed multiple valves off the pistons.

You probably bent alot a pushrods and possible a couple valves.

On the bright side you have nice valve reliefs in your pistons now and can probably run a bigger cam

Cricket99SS

Yeah expect a couple hundred dollars to have your heads redone. Probably gonna take a couple new intake valves, and if you cracked the valve guides in the head, you'll need those pressed in also. And if you are running stock pushrods, there is a 99% chance like Chris said that those are bent too.

In my case, when I floated some valves due to old crappy valve springs, my chromoly pushrods all came out perfectly straight. However, I had bent a valve pretty good.

Time to pull the heads and see just what all got borked up.

Colonel

LMAOatChris!

That sucks man. Time to make some upgrades.

Tech

iTrader: (1)

Stock heads, stock pushrods. You think damage was done to the pistons or valves before he would have bent a pushrod? I'll be taking apart the top end in a couple of days for him.

94form2000z

iTrader: (10)

At the very least you've bent the pushrods. They are cheap I'd start there.

pdd

iTrader: (3)

o man that sux. good luck with the fix

DenzSS

Pretty much everything, Tech. The entire top end of the motor needs to be disassembled. 4th to 2nd is an incredibly high mechanical "over-rev".

You have likely kissed the pistons, broke some valvesprings, bent some pushrods, and who knows what else. Sorry, it sucks.

crainholio

iTrader: (2)

Before tearing it down, I'd pull and check the pushrods. Replace any bent ones (the old roll 'em on a glass pane test works fine) and re-test the car.

With a stock cam, it's entirely possible to bend pushrods without the valves having hit the pistons...just simple valve float. I've seen two LS1 cars running stock/small cams do this, no bent valves or kissed pistons, just a bent pushrod or two.

Start w/ the pushrods, see what you get, then do a teardown if necessary.

Mike K.

ouch!! hopefully its just the pushrods. If not time to upgrade.

DenzSS

You won't get a consistent misfire and the symptoms he is describing from a bent pushrod. Replacing pushrods is a waste of time and you'll risk further damage to the engine.

Situations like this require a full top-end postmortem.

crainholio

iTrader: (2)

Totally displaced or broken pushrod would cause what he's describing. Especially if it happened to be on the exhaust side.

Not arguing w/ you, just suggesting some diagnosis. If he was running a King Kong cam with lots of lift I'd agree it's time for a teardown, but with a stock cam...low lift, short duration...there is some likelihood the valves and pistons didn't meet.

While you're pulling pushrods, whip out your compression gauge or leakdown tester and you'll know if you bent a valve and/or holed a piston.

Inspector12

iTrader: (29)

The only thing I am going to say is start with the easiest and check every thing twice. Could be some thing all the experts have not had happen. Not likely but possible. LOL! Good Luck!

DaleMX

iTrader: (4)

I would do a leakdown test first then if you pass you can change the pushrods and inspect the springs.

furiouSS99

iTrader: (-1)

Look at it this way, this is a great argument to use on your wife or girlfriend that you need a loan for new heads and a cam!!

jd13

iTrader: (3)

If it's shaking that bad you more then likely knocked up a valve (which explains the misfire on 5). You definatly have some bent pushrods.

Thank God you've got a buddy looking at it for you. If you were to take it to a dealership they would charge you about $4000 to do all the work required to replace just valves and pushrods. Just imagine if you damaged the pistons or heads.

onyxxtreme

iTrader: (4)

I did a 1-2-1 shift before, never bent any PR's or valves
but a small cloud of smoke came up out of the shift-boot, so I think maybe thats why my pilot bearing exploded?

SSEUL8R

the guy that had my car before me told me he bent a few PR's on night on a blown shift. I thought OK, whatever, then when I pulled the valvecovers off the first time, I found about 5 egg shaped holes where the PR's go down to the lifters. Everything was ok, my heads just had a couple scars from the wound he caused. Nice. Not a big deal now though, the car runs hard and everything is ok. Oh yeah, and that guy drives a 500 rwhp 03 cobra now.

66ImpalaLT1

Good move for him, those dont have any pushrods.

Spinmonster

I would just get LS6 complete castings from Pace for 1400 and put them on. You can sell your LS1's for 200. No down time and you get to see the tops of all the pistons while they are off. Use thinner gaskets to get to 11:1 CR while you are at it. Good luck.