Spun rod bearing..

[F1scamp]

Anybody run into this? I feel like I am the lucky s.o.b... Instead of putting the car away for the winter Saturday, I decided to run at Englishtown Sunday. Did an oil change Friday, put a touch extra oil in it since I spin it to 7700rpm shifts, 5w/30 max life.
Track was pretty bad, had to turn first gear down 15%, second 10% (stock tires), fourth pass it went 11.22 @ 133.7mph. Fifth pass everything felt fine, no noises, clicked it into neutral through the traps and that's all she wrote. Motor locked up. Of course I drove it instead of towing... Had to get it towed 187mi to the shop, pulled the motor Monday, haven't gotten it all the way torn down but #3 rod is blue and the bearing is in the pan.
Particulars of the car 16 gt, manual, stage2 whipple, 3.75 pulley, boundary opg, t.s.s. crank gear, ati balancer. 10k on motor, 5k on whipple and gears, 24 passes.

What the heck did I do wrong?

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[wildcatgoal]

How much extra oil? Not sure why you put more oil than it calls for in because you go to 7,700. Probably not the issue I was just confused by this...

 

[F1scamp]

About a quarter quart. I have been plagued in the past with a car that the rules mandated a stock oil pan, and it would suck the pan dry at the top of the track. The higher the rpm, the more oil the oil pump picks up, more oil is out of the pan.

 

[Roh92cp]

About a quarter quart. I have been plagued in the past with a car that the rules mandated a stock oil pan, and it would suck the pan dry at the top of the track. The higher the rpm, the more oil the oil pump picks up, more oil is out of the pan.

Very sorry to hear about that, and you wouldn't be the first to loose a rod bearing. As far as th oil, I've heard that running high rpm and with extra oil can cause a frothing effect. The extra oil gets beaten by the crank and starts to foam or froth an airate, which can cause loose of good oil flow. Who knows what's happened in your case. Are you sure your oil was fully warmed when you ran it? The reason I ask is since I've installed a dedicated oil temp gauge I've realized how long it takes for oil to reach 180 degrees.

 

[F1scamp]

With the factory windage tray, and the crank being that far up in the block, and the fact that it was at high rpm for at least 10 seconds I don't see how oil would be near the crank.. I used a quarter extra quart when I changed the oil last time, actually showed right on the line on the stick.
I have no idea what the oil temp was, it certainly wasn't stone cold, coolant temp was at normal reading, it was driven 200 miles down in the morning and it was the 5th pass of the day.

 

[wildcatgoal]

Is it possible the oil filter caused a blockage or something like that? I mean... for this to happen there would have had to been no oil there like... at all... seemingly in a brief period of time considering you said it was running fine until pooof. I don't know lots about bottom ends, though. Sucks... but opportunity to build up the engine now for MORE POWAAAAA.

 

[Roh92cp]

With the factory windage tray, and the crank being that far up in the block, and the fact that it was at high rpm for at least 10 seconds I don't see how oil would be near the crank.. I used a quarter extra quart when I changed the oil last time, actually showed right on the line on the stick.
I have no idea what the oil temp was, it certainly wasn't stone cold, coolant temp was at normal reading, it was driven 200 miles down in the morning and it was the 5th pass of the day.

True with the windage tray it would be hard for the crank to hit the oil, so maybe it's a non factor. And with a 200 mile drive the oil should have been plenty warm unless you had a long cool down period and then hit the track.

 

[jasonstang]

That sucks. Sounds like for whatever reason that bearing is not getting oil.
A defect in the oil path?

 

[Excelerater]

Extra quart on a 8 quart system is a waste of oil and prob does more harm then good,actually hard core racers run less oil for many reasons but never more..

Yous spun bearing could be from many factors but 7700 RPM with stock rod bolts is something Id never do. Been drag racing for 20+ years,far as Ill push a stock motor is low 7000s,if you wanna rev higher you need better hardware. Good time to upgrade is now,forged pistons,stainless rings,billet rods and balanced assembly,your good to go . Make sure your piston didnt wack the head or valves,one step further is a real race valve job on these motors,goes a long way HP wise

 

[SolarFlare]

I will likely stick with 7000-7100 when I do the procharger, maybe 7300 if I do E85. I'll gladly give up the 20whp from 7300- 7700.

Sorry to hear that OP. Build it stronger during the winter.

 

[Tommy V]

When lund starting tuning my procharger i did not say anything about rpms.Every time he ask for a log he said to give him a pull from 2500 to 7200 rpms,my thought was its probably a good reason for that so i didnt ask him to tune for any higher rpm.

 

[ghostnote]

Just out of curiosity, how much will something like this set you back?

 

[SolarFlare]

Isn't an aluminator something like 4k for a complete short block? Seems like the fastest route.

 

[mustang_guy]

Extra quart on a 8 quart system is a waste of oil and prob does more harm then good,actually hard core racers run less oil for many reasons but never more..

Yous spun bearing could be from many factors but 7700 RPM with stock rod bolts is something Id never do. Been drag racing for 20+ years,far as Ill push a stock motor is low 7000s,if you wanna rev higher you need better hardware. Good time to upgrade is now,forged pistons,stainless rings,billet rods and balanced assembly,your good to go . Make sure your piston didnt wack the head or valves,one step further is a real race valve job on these motors,goes a long way HP wise

Yeah that just isnt true. You realize this is an improved 302 boss engine we have, right? We have their rods, bearings and rod bolts. The largest difference betweem us and a boss is our cobra jet intake cams and 302 boss exhuast cams. Our heads are not cnc ported like the boss. We also have bigger valves slightly and our heads are cast with these valves in mind and stiffer valve springs. The only thing we dont have is their forged pistons, timing chain tensioners, harmonic balancer and intake manifold. Missing those few of things at 7700 wouldnt cause a spun rod bearing. Broken oil pump gear, sure eventually.

 

[Super Werty]

Spinning that high and boosted I would only use amsoil or motul.. Just my opinion.

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