Hurt my car tonight... Need advice

IBChillin32182

Founding Member
Mar 23, 2000
167
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16
Shepherdsville, KY
Tonight I was giving my friend a ride in my Bullitt I just purchased a few weeks ago. I ran the car up to about in 5800-5900 rpms in first and shifted and when the car reached around 4500 and 5000 in second the car fell on its face so I let out. When I put the car back into gear it was missing on one cylinder. I'm pretty sure I bent a valve. What should I upgrade as far as valves and valve springs and also what brand. Should I upgrade both or just one of them. I am new to the 4.6 engines so I don't really know their weak points. I knew the connecting rods and pistons were weak but I dont know anything about the top end of these engines. The car has a ATI P1SC on it running 7 #s. The car put down 360 hp under load during tuning on a dyno.
 
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Thats a pretty low RPM to bend a valve.. but possible. I did the same thing.. but at 8400 haha.. gotta love a misshift and no rev limiter. anyway, I would go ahead and have the heads worked since you have to pull at least one off anyway. And you might wanna make sure you didnt spin a bearing also. We though I had only bent a valve also until we got the car finished only to hear a knock.

Check out patriot, VT, Steen for ported heads, and I know I am forgeting some real good names just drawing a blank. It is very disheartning.. I felt like crap when I went through it.. just take this chance to upgrade and itll be a great experience. :nice:
 
My friend mentioned that I should look into the Patriot heads if it is really a bent valve. I figured I might as well upgrade while the car is apart too. I would really like to get a forged bottom end while I'm at it but I dont have the cash for all of that at the moment.
 
VERY unlikely that its a bent valve. Its really tough for the valves to unload and be "launched". Like above happened @ 8400ish.

I run mine to 6200 all the time, and have hit the 6500 limiter more than once. RPM is what causes this, not a blower...weaker the valve springs the lower the RPM that this will happen.(ie high milage engine)

Check all of your spark plugs FIRST...could have had a hint of detination and closed the gap on one of the plugs. :nice: then follow up with a compression check while all the plugs are out. Get back to us.
 
hotmustang331 said:
VERY unlikely that its a bent valve. Its really tough for the valves to unload and be "launched". Like above happened @ 8400ish.

I run mine to 6200 all the time, and have hit the 6500 limiter more than once. RPM is what causes this, not a blower...weaker the valve springs the lower the RPM that this will happen.(ie high milage engine)

Check all of your spark plugs FIRST...could have had a hint of detination and closed the gap on one of the plugs. :nice: then follow up with a compression check while all the plugs are out. Get back to us.


good advice, I know mine sounded HORRIBLE when it happened.. you could hear the air being pushed back through the intake.
 
There is no check engine light. I didnt have a chance last night to see exactly which cylinder is missing. I know it is on the drivers side though. The car is bealching raw gas out the tailpipe whenever its on the dead cylinder. I had the car towed to my mechanic so hopefully he can look at it today and let me know whats wrong.
 
Another area to look is the coilpacks. I mishifted once and bounced off my rev limiter. Shortly thereafter I was misfiring...turned out I needed to replace the coilpack. I got no CEL either, but when I plugged my OBDII sure enough it logged an error code for the misfire and which cylinder it was.
 
i also do not think it is a bant valve. i also run my rpm higher then that with no problems. ford set the rev limiter higher then that so that no damage would be done to the car. you didnt even touch the limiter.

as far as the blower, i think you will blow your internals before you damage anything in the heads.
 
Well I just talked to my mechanic and it is definitely at least a bent valve. The spark plug was also crushed. There may be more damage...They are taking the head off tomorrow to see if there is any more damage. He said there was a ton of carbon buildup on the piston.
 
IBChillin32182 said:
Well I just talked to my mechanic and it is definitely at least a bent valve. The spark plug was also crushed. There may be more damage...They are taking the head off tomorrow to see if there is any more damage. He said there was a ton of carbon buildup on the piston.


the spark plug could have been crushed from violent detonation. try putting another plug in before you pull the head.

or just go ahead and not even try the plug ( it would take a few minutes) and maybe waste thousands.