Blown 351 cleavor

[hertelbr]

I have a SVC with a 351 cleavor (351 winsor block cleveland heads). Engine seized up after 1100 miles. Rod bearings spun, and machine shop said it was getting too much fuel which caused the melt down. Pulled the plugs and they were a perfect cardboard brown, no carbon build up. My dilemma is what to do next. The crank was to badly scored to use so do I put it back together the same or stroke it to a 38? or 409, the guy I purchased the car from claimed 470 hp. Any suggestions or advice would be appreciated.

[blykins]

How many bearings spun? What were the rod clearances?

Too much fuel over a very long period of time will cause damage....but not of that kind....the gasoline will actually etch the bearings and rings...but I don't think it would cause them to spin in the bores.

470hp? Sounds kinda optimistic. Did it run on pump gas?

To answer your question, I would stroke it...Of course you will need a new crank, rods, and pistons if you do so. How far? Depends what you're wanting. There's no substitute for cubes....but with the bore constraints of a Windsor block, it's generally the longer the stroke the more torque you're gonna get....and at a lower rpm. The shorter the stroke, less torque, but more horsepower....and at a higher rpm.

[427sharpe]

Have to be careful trying to stroke a cleveland/Windsor combo. get a REALLY good engine builder and follow his advice carefully. The piston to valve clearance on the canted valve head is pretty close in a stock cleavor, so you would probably have to have some pistons fly cut for a stroker.

[phatry5]

The guy may have ran it without oil, after a change...ect. and done damage. You just happen to be there when it went.

[750hp]

Did your machine shop, or the seller's machine shop say that? Was your oil pressure stable previously? Your info says that the car was built in 2003, so it's not like the motor has reached it's normal service life. Make sure you get to the bottom of why it happened to make sure it doesn't happen again...

Scat seem to make a popular crankshaft and conrod at a very reasonable price, so you might get the extra cubes for not a lot of extra coin. As 427s mentioned, do some homework with the piston choice.

[tpiini]

Originally posted by 427sharpe


Have to be careful trying to stroke a cleveland/Windsor combo. get a REALLY good engine builder and follow his advice carefully. The piston to valve clearance on the canted valve head is pretty close in a stock cleavor, so you would probably have to have some pistons fly cut for a stroker.

I hope this doesn't turn out to be the dumbest question of the week. But if you stroke ANY engine, so long as you match the stroke/rod length/piston pin height, you still end up with the same deck clearance as a stocker, right? Is there something different about the Cleveland heads? I've only seen them assembled to an engine.

[750hp]

The big difference with the Cleveland heads is that the valve reliefs machines into "off the shelf" pistons will be based on valve angles of Windsor heads. For the same reason that you need pistons specific to a TFS-R head, or a Yates head, you need to match the piston design to a Clevo head.

[tpiini]

Now THAT makes sense!

Thank you for taking the time to educate me.

Tom

[hertelbr]

Great information guys. The car only has 1200 miles on it. It has a high flow oil pump. I was only reading 10 psi at idle and 20 psi at speed on a mechanical oil gauge. As you can probably tell I am hardly a gear head. I have a mechanic that works for me doing most of the work and have the heads and short block at a reputable machine shop being hot dipped and gone over. And yes the pistons are different they are not domed but have the clearance of the huge valves of the cleveland heads cut into them. I am leaning towards staying with my current set up but would not mind putting in a few extras if I could keep it in the $ 3,000.00 range. 4 of the rod bearings were spun all towards the backside of the motor. Keep the info. coming I am like a big sponge taking it all in.

[blykins]

I think $3000 is definitely do-able. I paid $600 for my Eagle ESP 4340 forged crank....4.100" stroke.....$600 for my Eagle H-Beam rods, and $600 for my pistons. You may have to clearance the block if you go with a real long stroke....And of course you'll need machine work and bearings.

You didn't have much oil pressure...that's for sure. What's got me worried is that you had a high flow pump with low oil pressure. Was it a low capacity pan? The engine could have been starved for oil constantly because the pan was constantly being sucked dry.

Four spun rod bearings would clue me into something else being wrong besides running rich. Clearances could have been off.....But would be led to believe there was not enough oil to the engine....

If you rebuild it, make sure you have a high capacity oil pan if you use a high volume pump.....6-7 quarts at least.

That Clevor combo would probably like some high revs with those heads....I would go with a stroker combo.....probably a 3.85" stroke....match the cam and intake with it. I think you would be very very happy....and would come in under or meet your $3000 budget.

[hertelbr]

blykins,

It does have a high capacity oil pan 9 qts. I believe. The oil level has always been right on since I have owned it. I use a K & N oil filter and Amsoil synthetic.

[blykins]

Hmmm....that's a tough one. I really really doubt that the air/fuel mixture had anything to do with it with just 1000 miles on the clock.

Either there was a plug left out of the oil system and it was starved for oil...or the rod clearances were so far off...

I can't remember guys....can't excessive clearances spin a bearing? If so, that could be the culprit of the spun bearing and the low oil pressure.

I have a 7 quart pan and Melling high volume pump on my Windsor. Oil pressure is 65psi cold....and about 50-55 (at idle) if I remember correct at operating temp.

I think there's an old addage that says you need 10 psi for every 1000 rpms you turn....

With 20psi at speed, you were only good for 2000 rpms.

[cobrashoch]

The story on the cause of the failure is with the crank and rod bearings on the journals that did NOT spin. It does sound like it's a oil problem though. Hard to call it over the internet. It "could" be a clearance problem that caused either low oil pressure or bearing slap (or both) but you would have heard something rattling or knocking before it cut loose while you was driving it those 1000 miles I think. Low oil pressure could be from a lifter/block mismatch too. Clevors need the blocks drilled to cool em on the street. Was that done? I can ask a thousand questions,,,,,,,,,,,As for running a stroker, I've yet to talk to anyone (that means ZERO) in my 59 years that regrets running a stroker once they get them sorted. Can't say the same thing about the various other hot rod stuff out there.
cobrashock

[427sharpe]

check the clearance between the bottom of the pan and the oil pick up on the pump...if the pickup is too close, it would cause the starvation problem. Should be about1/8-- 1/4" between the bottom of the pick up and the pan.

[hertelbr]

To answer your question

The cleveland heads were re-drilled to match up with the winsor cooling ports. Freeze plugs were installed over the old ports, I was surprised they were not welded.

[hertelbr]

I will also check the clearance I had not thought of that thanks to all who are trying to help me through these trying times.
signed, still walking, wish I was driving.

[Bruce Edwards]

Why not just re-ring it and install a crank kit and a few new rods? Sounds like you had low oil pressure due to damage at some time that opened up the rod clearence. As long as the mains did not spin you could fix what you have and save yourself a fair bit of change.
Install a new oil pump and be sure to check your clearences. Rule of thumb is 10 psi per 1,000 rpm. So if you can spin it to 6,000 you need 60 psi when you get it off of idle speed.
20psi is not enough to run a high end V-8.

[lovehamr]

I would be interested in hearing what your combination is. Did they just slap canted valve heads over fly cut flat top pistons? That sounds weird but OK. Do you know what the other rods and the mains mic-ed out to? As for the oiling problem (rest assured from what you wrote it's not a fuel problem) the only ways that I can think of for an engine to have pressure that low are, in no particular order;

#1 A stuck pressure relief valve on the pump its self.
#2 A poorly done oil restrictor system.
#3 Massively oversized clearances on the rod and main bearings.
#4 An oil galley plug missing or leaking allot. The one at the rear of the lifter valley comes to mind. (I guess this could be #2 as well. LOL)
#5 A blocked pick-up. Could be the pan clearance or just junk in it.

That pretty much sums up what I could come up with. Hope it helps.
Steve

[cobrashoch]

hertelbr - it's the block that needs drilled not the heads. Some drag guys do not drill 'em' somethimes, they want to hold the heat on the topside. As for the bearing problem, how did stuff mic out? I still think that it's a oil problem of some sort though.
cobrashock