Well...my motor seized...it didn't last very long. Everything sounded great was running fine...had plenty of oil pressure and it either dropped a valve or threw a rod...I am leaning toward dropping a valve because it will not turn at all anymore and there was no sudden mechanical knock. I was able to turn off the motor and then when I tried to restart it cranked fine a couple of times and then the motor would not turn. I didn't check the valve job that the Cosworth heads came with assuming they were installed correctly. I can't really say for sure right now. I will know for sure in a few days so it looks like no dyno numbers anytime soon.

 

Man that sucks, I wish you best of luck with the new rebuild.

 

That is horrible. If Cosworth did indeed install the retainers improperly is there a guarantee on workmanship? Either way, I hope you get it resolved and running soon.

 

I wouldn't be disappointed if the motor seized when I was on the track turning 7500 rpm but for it not to last long enough to take the car home is pretty disappointing. Well time to get up off the floor and try again. Well looks like I will be out of a car for another couple of months.

 

The weird thing is I saw the original post tonight and then went to the last post thinking to myself...I wonder how it went???...then I saw his last post and DAYUM!!!

 

You know I just realized when the last time the motor shut off on the video the engine never restarted. It cranked over when we tried to start it back up but it just turned a couple of times and then seized. At first I thought the battery was just weak, then we checked the starter and when we tried to turn the motor we realized it was seized. I am no mechanic but I think a bent valve and the motor would still turn.

Reyes5937, the sound didn't sound like a Ferarri or an American V8. Its kinda of hard to describe the sound in person. The idle sounded similiar to one of the ALMS motors at idle and when reving to about 6000 it sounded like a small displacement high revving race car.

 

I am sorry to hear what happend . I hope everything runs prefect this time.

 

damn dude. I hate that

 

Well I spoke to my builder today he is already pulling out the motor. He thinks he will know what happened by Friday so I can order another shortblock if needed. Once I know hopefully I can get another engine with either the same parts or equivalant parts in pretty quickly.

 

Good luck - I'll never forget the look on my Dad's face when one of his Formula Atlantic engines, freshly built, sheared a pulley on a cam and came to a sudden demise after running less than about 10 minutes - wasn't pretty.

Almost sounds like bad lower end problem, like a seized rod bearing or broken retaining bolt...but if a cam won't turn due to a valve problem, engine won't turnover either. Hopefully a top-end problem, maybe can recover some cost if the problem came that way from Cosworth.

Sorry to hear about the problems, good luck getting things back on track soon!

 

Curious why the low CR? You could easily run 12:1 on 91 octane with a conservative tune. You might even be fine wth 12.5:1. If you run a UTEC with switchable maps, you can have a second more aggressive tune (more advanced ignition timing) for 100 octane. Not slamming you decision, just curious why so conservative?

 

Well the problem ended up being the rod bolt that had a problem originally. I was to cheap to buy another rod. The block is still good but I am going with a Cosworth shortblock instead of rebuilding the motor. I will keep everyone updated on the progress with the new block.

I didn't want to have some to make custom pistons. Plus I am not sure what the limits are on pump gas with this motor. Most likely running 12:1 would not run on standard pump gas with this motor unless the tune was extremely conservative and that would not make it worth the extra expense.

 

Good to see your project on the go. I was also wondering if you looked into the water/meth injection kit to have a high compression like 12.1 to 1 on pump gas to keep it safe for detonation. Maybe you can run more timing for more power with the kit.

 

static compression means nothing. The combination of a good set of heads, pistons, cams and head gasket really change up the CR. One can use 11 CR pistons and end up with a CR of 9.5 depending on the choice of heads and headgasket.
If i was doing an N/A build, I would stick to 11 or 11.5 CR pistons so you can get an aggressive tune with race gas, or a moderate tune to 93.

 

+1 I from 11 CR pistons I ended up with 10.7. I am shooting for an moderate tune on pump gas and really aggressive with C10 gas for track events.

 

[QUOTE=rednezz]Well the problem ended up being the rod bolt that had a problem originally. I was to cheap to buy another rod. The block is still good but I am going with a Cosworth shortblock instead of rebuilding the motor. I will keep everyone updated on the progress with the new block. [QUOTE]

Looking forward to hearing how this turns out. Thanks for sharing your build! Let me know if you're considering selling your shortblock, I'm about to start a similar project.

 

Yeah I plan on selling my original shortblock after I get my car running with the Cosworth. I just want to keep it long enough just in case I do need to go back and rebuild it if I have problems with the Cosworth as well.

 

How your Cosworth build coming.

 

why dont we measure optimal velocity on the z and come up with optimal parameters?

 

good luck man. How much hp are you shooting for?