Old Geezer

iTrader: (3)

Ne pics of the main cap parting faces??
Clean the oil off the block main brg faces, and re-take the pics.
No knock? What's the sensor[s] torqued to? Are they even working?

1SIKZ31

iTrader: (5)

Oops! Yea that's what I meant 3 thousandths not 30! Lol.

I wonder if my oil is to thick? 20w50... should I go to a synthetic and lighter weight oil? 15w40?

Speer13... thanks for that info! Good to know !
We're getting rid of the stock crank and putting in a Eagle 4340 so if it is/was a crank issue it'll automatically be solved... that's crazy though...

Old geezer I honestly have no idea on the knock sensors but I do know there was no knock count and the plugs looked fine to me. My machinist said that the plugs show detonation because of where the ground strap is burned...

I'm using 24gph nozzles which is the same nozzles everyone else is using from what I've seen... it turns on at 5 pounds and progressively increases and is at 100 percent at 12 pounds...

dazman

a good rule of thumb is if your going to go as far as replace the pistons and rods, then why not the crank. everyone knows this stuff isnt budget minded. should have new bearing too... everywhere.

OR.. it may be time for that 408 from one of the vendors..

dazman

i remember when i put the heads and cam in my stock corvette... i had it blown up in a month. called texas speed, orded a 408, back in 2008 and never looked back .... drove car around yesterday all over town with 600hp on the spray.

S10xGN

iTrader: (11)

RockinWs6, how'd you get me quoted saying this? It's not from me!

To back this up, here's an animation of a multiplane crank at high RPM that shows what the journals are going through. Couldn't find one based on load but I'm sure the effects would be similar...

A.R. Shale Targa

iTrader: (2)

The weakest link in the system is the soft aluminum babbitt bearings. Making
your kind of power does require a H-race style bearing but again look at the
difference of your rod bearings. The shell in the cap looks evenly worn from
the shrapnel particles flushing through it. The rod shell has concentrated
wear directly in the middle....again crank moving up and preignition pushing
down....BIG forces which can easily overcome the thin layer of oil pressure.
This isn't a pump, pressure, or oil viscosity issue. Your bearings look far
worse than some of my circle track(dirt) customers after the whole season..
which typically requires 13-1500 dyno pulls (figuring 2 7500 rpm blasts/lap)
My customers that choose to ignore my timing recomendations usually don't
make it through the season regardless of the quality of their parts.

X-Bomb Racing

iTrader: (1)

Should aluminum bearing not be used in a higher hp app? I just reused my factory mains but bought the aluminum rod bearings. which i believe are stock replacements.

1SIKZ31

iTrader: (5)

That's crazy..
If it's detonation what the hell would cause it?
I've got the following conditions and they timing is extremely reasonable...
Compression is at 10:1..
11.7:1 A/F under boost (we watched the data log on the run where it lost oil pressure and we're using a brand new sensor...
Timing was at 16 degrees
We're on 93 octane with 24gph meth nozzles (two 12gph nozzles)
Injector duty cycle only at 60 percent
16lbs boost on a 76mm turbo.
iat's under boost went from 99 degrees ambient out of boost to 72 degrees under boost
And we're using 1 step cooler plugs (br7ef)

Seems safe but I may be wrong...

Any insight to why it would detonate?

stoning_volcom

iTrader: (6)

When you build a engine to support 700+ hp you are asking for a car that is fast but can explode. especially on a stock crank, not saying it hasnt been done as it has. But it is smart to upgrade them, seeing as you were sayin you were making pulls all day that motor was warm, as was the crank. So the crank very well could have shifted. Now i could see if the center clearences were off by a lil bit it could eat the center then 2-4 mains. Possibly thrust wasnt set properly, but when building a preformance car/engine you have to expect problems to arise. Cause if you dont, then you will not be looking for the signs that could point to the problem. Now you said the oil pressure dropped after you let off the throttle, but befor you let off did the oil pressure change/vary? during the pull. what are the build sheet specs? can you post a pic?

BLK95-Z

iTrader: (2)

These guy's are making over 1k to the tire with stock cranks putting up real results. Several threads on YB about this. I think your having other issues IMHO

http://www.yellowbullet.com/forum/sh...d.php?t=586066

A.R. Shale Targa

iTrader: (2)

[QUOTE=1SIKZ31;17768926]That's crazy..
If it's detonation what the hell would cause it?
I've got the following conditions and they timing is extremely reasonable...
Compression is at 10:1..
11.7:1 A/F under boost (we watched the data log on the run where it lost oil pressure and we're using a brand new sensor...
Timing was at 16 degrees
We're on 93 octane with 24gph meth nozzles (two 12gph nozzles)
Injector duty cycle only at 60 percent
16lbs boost on a 76mm turbo.
iat's under boost went from 99 degrees ambient out of boost to 72 degrees under boost
And we're using 1 step cooler plugs (br7ef)]

Seems safe but I may be wrong...
GM had the timing on my 10:1 LQ9 at 21 degrees with a cylinder pressure of
maybe 180 psi. Don't know for sure as I never pumped it. Now 16 lbs. of
boost is more than one full atmosphere which means your 364 incher thinks
it is actually an 800 incher. I'd bet the cylinder pressure is up around 250psi
which is completely insane. On 93 with meth IMO it still should only have 10
or at most maybe 11 degrees of advance. A nitrous guru once told me that
you will never ruin an engine thats too lean, but too much timing will always
kill good parts. They're only air pumps and it's about controlling the POP !!!!

RockinWs6

Now that's a smart post. I've seen timing ruin a lot of good engines QUICKLY.

RockinWs6

Well It had to be there when I posted...................

Forcefed86

iTrader: (4)

Sounds like it was put together incorrectly to me. The crank sure as hell isn't flexing at those power levels and the bearing material is fine. (maybe not ideal, but fine). I'd get a new engine builder stat. You would have been better with a bone stock engine.

I run a bone stock 160k 2001 short block 5.3. Right down to the hardware. OEM 6.0 heads. I took it all apart and put it all back together with the original OEM bearings and hardware. All the TTY hardware that your not suppose to reuse... I did. Making over 800 whp through an auto and a 9" rear for well over a year now. Roughly 100 1/4 mile runs at 24lbs of boost.

RockinWs6

Without knowing how it was built, everything checked properly etc It's impossible to to say what happened to this mess. I suspect a bunch of different things wrong that added up to this.


Move on but do it right this time, you have to have reliable builder that knows LS1 engines. I call um the Aluminum freak engine, you can do everything right and still get kicked in the head.

Burken01

iTrader: (88)

Impressive, if my engine lets loose im throwing a stock 5.3 in...

HRD

iTrader: (1)

"On a second note I would be sure that you don't have to big of water/meth injection nozzles, you may be trying to compress water in some cylinders causing flex on the crank......."

I agree.
Too much water/meth could have the same effects as detonation on the bottom end due to the absurd cyl pressure but you may not see it in the pistons, plugs or knock count in your datalog because it's not knock, it's hydra lock or at least approaching it.

Forcefed86

iTrader: (4)

Negative guys...Thats total BS. Thats no where near enough water to harm anything.

*Most* of the Detonation I've seen hammers the rod bearings pretty bad. They usually fall right out of the rod/cap if the detonation is bad enough. Your rod bearings don't look to bad aside from the all the garbage that went through them from the mains crapping out.

*Usually* there are signs on the plugs and pitting on the piston faces if the motor was detonating. Doesn't look like the case here. Looks like oil starvation or incorrect assy to me. (IMO, oil weights don't have a damn thing to do with a failure like that) Pretty typical for inexperienced builders to forget the o-ring on the oil pickup tube or have the incorrect tube for the pan, loose pickup etc? The LS series is also known to slosh the oil away from the pickup on hard launches. I run a quart over full to help with this. Again though that's catastrophic failure. Not something thats a little "off" that would take the motor out over time.

ADM

I am rebuilding my friends GTO's LS1 engine and we found #3 and #4 main caps put on the wrong way around. And of course, their bearings looked like absolute ****. So much metal was missing from their surfaces I am surprised it was still running smooth in that condition. Had to turn the crank for 0.010" bearings.

Even found the pick up tube bolt sitting in the oil pan. Go figure!

Check the directions of the main caps. Its possible the guy put them on wrong as we all make mistakes and you also mentioned he is an old school engine builder.

SlowBurn

iTrader: (7)

the amount of threads I see like this have pretty much sealed it for me, when I do needs a new short block, I think I'll just buy one fully built from one of the big names like TSP, Vengeance, or HKE.