Engine Autopsy Concluded...

[Lumpydogs]

Recap. Cobra died at Gingerman Raceway last September. Was trailered back to Lidio at Alternative Auto Performance. Engine failure was unknown.

The Autopsy on my cobra engine determined that the oil pump failed and eventually seized up. Oil starvation to the bottom end ground the rod bearings and galled the crank. Also, the keyway in the crank sensor cog(?) was elongated to double its normal width.

The good news is that the block is re-assembled and ready to be put back in.

Before you ask, no I didn't see my oil pressure gauge drop but then again I don't do a very good job of watching my gauges while on track. :nono:

 

[racer]

That sucked, good to see it back together. Best of luck with this one.

 

[brkntrxn]

Good luck with the new setup. Are you going to do anything else to it while it is out?

 

[BlackBolt9]

I spy a Canton oil pan:-D

Glad to see you got it all back together and she'll be ready for the track again next summer.:rockon:

 

[Sniperdog]

ouchie glad its back together :thumbsup:

 

[Ryan]

I spy a Canton oil pan:-D

What gave that away?:banana:

:rockon:

 

[ac427cobra]

Jeff:

Looks good man! :-D That Canton pan is going to help! ;-)

Hope you have some funds left over for track events!? :dancenana:

 

[HYBRED]

What oil pump did you go with for this build?

 

[Lumpydogs]

Thanks Guys, and here are some answers.

New/rebuilt engine is stroked to approximately 300 cubes. A Terminator radiator replaced my stock 01 radiator. Brand new Alternator. The AC condenser, hoses, etc. accidentally fell off :rollseyes

Yes, finally got the Canton pan installed. (6 months and one blown engine later).

Track funds are still viable, thanks to my super fantastic wifey and her job.

Rebuilt using a standard OEM replacement oil pump. I'm still not convinced the oil pump was the problem and not a symptom. There was sooo much metal swimming around that engine when it died. It's no wonder the pump impeller shattered.

 

[gcassidy]

Nice rebuild. I'd like those cubes in mine!

Mind if I ask milage on motor when it gave out, including track milage?

 

[Lumpydogs]

Approximately 26k total miles. Best estimate is 20 track hours.

Engine internals were 100% stock. Basic bolt ons and a moderately rich tune.

 

[Yellow Iron]

Get rid of the underdrive balancer. Two things kill oil pumps, detonation or vibration. The fact that the keyway in the trigger wheel was worn would tell you that the damper was loose or out of balance. Also use a new bolt in the crank snout. They need to be replaced every time unless you have an ARP. I agree the oil pump failure was the result not the cause. I've seen this many times before.

 

[wheelhopper]

Note to self...check oil pressure gauge periodically on track.

 

[racer]

So it sounds like you did not replace the oil pump gears with billet ones. Any reason why? Are the stock 4v ones less resistant to vibration then the stock 2v ones.

 

[racebronco2]

I have thought about hooking up a low oil pressure light in my car because i have twice blown an oil line and if caught in time has very little damage.

 

[99COBRA2881]

Are the stock 4v ones less resistant to vibration then the stock 2v ones.

Still the same fragile powdered metal gear as the 2V, the only difference is that the 4V impeller is 2mm wider than the 2V impeller.

 

[PETSNKE]

Get rid of the underdrive balancer.

Wow, this is not the first time I've heard that.

I'm using the same Steeda underdrive pullies. I thought it was good to spin everthing a little bit slower on a car that sees 6K RPM so often during a driving session. Would you recommend I install the stockers back on?:??:

 

[BlackBolt9]

Thanks Guys, and here are some answers.

New/rebuilt engine is stroked to approximately 300 cubes. A Terminator radiator replaced my stock 01 radiator. Brand new Alternator. The AC condenser, hoses, etc. accidentally fell off :rollseyes

Yes, finally got the Canton pan installed. (6 months and one blown engine later).

Track funds are still viable, thanks to my super fantastic wifey and her job.

Rebuilt using a standard OEM replacement oil pump. I'm still not convinced the oil pump was the problem and not a symptom. There was sooo much metal swimming around that engine when it died. It's no wonder the pump impeller shattered.

Why do you still have a radio?oke: You might as well go for the "R" treatment as far along as you are now, an iPOD will suffice when you have to drive it any great distance :thumbsup:

EDIT: Oh and damn you for making the car even faster, I'm never going to be able to keep up with you again!!!

 

[Lumpydogs]

Oh and damn you for making the car even faster, I'm never going to be able to keep up with you again!!!

Ha, Ha. Look at the bright side. We are still tied for number of full course black flags we caused. :banana: Yours was just a whole lot less expensive :cryying:

 

[HYBRED]

Rebuilt using a standard OEM replacement oil pump.

I wouldn't do that...may not be the root cause, but it's just good insurance to upgrade something that important. The motor I'm using for my 4V swap can from a Mach 1 that shattered the gears in the oil pump. With as expensive as these motors are to just do a basic build on, I'd go with an aftermarket pump.