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Post by 94m6hardtopz on Apr 23, 2005 11:56:09 GMT -5
anybody installed one of these bolt on solid windage trays (like a moroso solid for SBC) on a stock shortblock car? just trying to figure out if i should start building a budget 355 instead of putting heads on my stock shortblock. the only thing im worried about on the stock shortblock is what the lack of a solid windage tray is going to do to the oil pressure at 7000 rpm. if i can bolt a tray on the stock shortblock in the stock oil pan w/o much hassle ill go that route. heres the part im looking at the tray from the moroso 23035 kit. www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=1766&prmenbr=361 |
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Post by '68SuperchargedLT1Camaro on Apr 23, 2005 12:46:24 GMT -5
Hey 94M6HardtopZ,
As far as I know, all LT1's have a solid windage tray from the factory. Mine had one. I wasn't the oringinal owner of the motor, so I'm not 100% positive, but it sure didn't look like an aftermarket tray.
Raymond
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Post by 94m6hardtopz on Apr 23, 2005 16:08:05 GMT -5
thats very interesting..............what year car did the engine come out of?
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Post by '68SuperchargedLT1Camaro on Apr 23, 2005 22:45:50 GMT -5
My LT1 is a '93 model. I beleive it came out of a Trans Am.
I'm pretty sure the windage tray is factory. I saw a pic of the same one I had in my engine in the GM Performance Parts catalog today.
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Post by Alex94TAGT on Apr 24, 2005 2:23:51 GMT -5
There is a factory windage tray -- should be on all LT1's. Not sure if the actual part changed for the 4-bolt main blocks, but I doubt it.
I've got mine out -- you want me to snap a quick photo for you? If you are missing it, I can get you the GM part number...
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Post by 94m6hardtopz on Apr 24, 2005 19:21:23 GMT -5
no pic needed. ive just never pulled a pan off a 'stock' motor, so i didnt know. i just put the heads/cam package on my stock shortblock. i was thinking maybe lack of a tray was causing oil pres fluctuations at high rpm and causing the spun bearing problem, but appearantly thats not it.
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Post by '68SuperchargedLT1Camaro on Apr 24, 2005 22:24:37 GMT -5
Did you spin a bearing?
Raymond
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Post by 94m6hardtopz on Apr 24, 2005 22:48:52 GMT -5
no, just all this talk of it has me a little paranoid, and i know a guy that just did a set of homeport heads and god knows what cam and he spun a bearing.
my buddies have never had a problem, and they did tons of them working at AMS over the years. they seem to think all this talk of oil pres and spun bearings after h/c installs has to do with messed up installs. but my motor has 85K on it now, so im trying to eliminate any variables.
the guy that spun the bearing wont give me any details, he just doesnt want to talk about it. so i am assuming its something they screwed up. the car went 86mph in the 1/8 w/ all the bolt ons, h/c, converter and 3.73s. my car went 84 w/ exhaust, CIA and pcm tuning.....and he cant believe it. i saw him last night, i was pretty loaded. but we didnt talk cars. he doesnt want any help, so whatever.
all the stock shortblock h/c lt1 cars my buddies have had have been m6 and have run 94mph w/ 4.10s. i would think the looser bearings on the higher mileage shortblocks would help as far as rpm, if the oil flow and viscosity was up to snuff. ive done dozens of h/c swaps on mustangs (my own and buddies) and never had a problem. i dont know what the deal is.
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Post by Alex94TAGT on Apr 25, 2005 18:15:45 GMT -5
Well, they say that unbolting/reinstalling the cylinder heads will put a slight 'twist' on the block, which can cause the mains to deflect slightly. It seems to be a luck of the draw deal. Supposedly, it's better to unbolt / reinstall one head at a time -- if you have that option.
I take it you're not hearing any loud 'knocking' noises from the motor (signifying a spun bearing)? Typically, the sound is directed towards the front of the engine block.
If you're tearing down the rotating assembly for a 355ci buildup, then I guess you'll find out exactly what kind of shape the stock bearings are in. I actually had quite a bit more wear than I was expecting at 70,000 miles -- I wonder if I've been running too thin of an oil. Always had good oil pressure. None of the bearings were spun, just the outer plating was starting to wear thru...
When you're in there, you could go ahead and get a new oil pump assembly with the upgraded pressure release spring. Get the metal driveshaft coupler as well. That will help protect the rotating assembly.
Of course, it's also vitally important to get the new assembly balanced. Talk to your automotive machine shop about this when you get to that point of the buildup.
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Post by 94m6hardtopz on Apr 26, 2005 11:25:43 GMT -5
these are 9.0 deck blocks that weigh over 160lbs, i gotta call BS on the whole mains twisting theory. the first time i read that in GMHTP i laughed. ive never seen that happen on a thin wall 5 liter ford casting, there is no way its gonna happen on these blocks.
im gonna roll the dice and do h/c on my stock shortblock. we've never had a problem before, i dont know why we'd have one now.
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Post by Alex94TAGT on Apr 26, 2005 13:37:25 GMT -5
It is just a theory -- I'm not sure if there's any true documented evidence. Then again, gravity is just a 'theory' that we haven't been able to prove false. I'm no expert, but I wouldn't rule anything out by any means. Far-stretched, sure, but not impossible...
IMHO, I bet a lot of spun bearings come from people performing a cam/head swap, followed by a feeling that their engine is somehow invincible. They pop in a cam that has a power range in the 7000rpm range, so they think it's OK to take their rotating assembly up there. Who would have guessed that over-revving the engine 1K past redline could cause premature bearing wear?
-Just another theory.
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Post by 94m6hardtopz on Apr 26, 2005 14:01:22 GMT -5
i know, im not attacking you personally, but if that were the case then a lot of other engines would have this problem. i did heads/cam on a buddies 91 lx coupe w/ 200k on it. compression is only 130psi. but w/ the heads/cam package i put on that 302 it makes 290rwhp and runs mid 7s@87-88 1/8 mile w/ 1.7 60ft on drag radials. the shortblock now has 250K on it, and its an anvil. the mains dont just walk in a cast iron block. i think its an oil sheer issue and/or faulty install.
lt1s, especially loose 'worn out' shortblocks, shouldnt have a problem revving to 7K if everything is right.
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Post by JoshuaJames on Apr 26, 2005 21:14:57 GMT -5
You know I always thought it was far feched but some people belive that after a motor is cast, machined, assembled, and heated and cooled several cycles the block casting could go through a core shift. This may not necessarily apply and I belive is far feched but is an interesting enough theory. Could have something to do with the factory freak theory. Maby someone who has worked in a machine shop and seen several align boors could shed some light in the subject.
I also want to say that when a machine shop align boors a block they have the torque plates installed to simulate the heads being installed on the block.
again I am not sure and don't belive this has any "bearing" on spun bearings with h/c swaps. Even a mediocre mechanic would have a hard time messing up the short block by replaceing the top end.
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Post by 94m6hardtopz on Apr 27, 2005 9:41:14 GMT -5
a cast iron block running 200 degrees shouldnt move enough to make a difference. and if that were the case the block would be moved enough to cause problems by 10K. back in the 70s no one except pro racers line bored the mains or bores, and it wasnt that big of an issue.
an aluminum block is a lot more likely to have core shift then an iron block, yet the ls1 shortblocks seem to be fine.
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Post by streetbad on May 5, 2005 21:52:54 GMT -5
I think 7000 is too fast. Let us know when and what gets hurt.
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