Carnage........Whats your take?

[Nick Micale]

Everyone here loves pictures, so if you do not want to believe Brian, Neal or Kenny, here are 6 plugs removed Friday from a 10 sec. GN and the ones from no. 1 and 2 cylinders should be obvious with ground electrodes about gone, and the center electrodes and porcelain almost gone.

The tune was fine and has been for a long while, BUT, this time Autolite 103 street plugs were installed instead of race plugs.

Big mistake to use projected tip plugs in a low 10 sec. or any high boost build.

This car does run a stock fuel rail.

On my race car that is fed with 2 -8 lines up front and 2 -8 returns on the rear, plugs no. 3 & 4 did run lean, but Cal has compensated for that with his tune in the XFI.

 

[czimpel]

Brian is right. This is something I mentioned over on the other board 10 or so years ago and got ridiculed for. This is based on actual dyno results by Kenny Duttweiler. It's true that the back 2 cylinders get the most airflow due to the stock intake manifold design but they also receive the most fuel flow due to the stock fuel rail design. The front 2 cylinders run leanest.

Neal

So powerplates do or don't help?

 

[Pittsburghkid]

Everyone here loves pictures, so if you do not want to believe Brian, Neal or Kenny, here are 6 plugs removed Friday from a 10 sec. GN and the ones from no. 1 and 2 cylinders should be obvious with ground electrodes about gone, and the center electrodes and porcelain almost gone.

The tune was fine and has been for a long while, BUT, this time Autolite 103 street plugs were installed instead of race plugs.

Big mistake to use projected tip plugs in a low 10 sec. or any high boost build.

This car does run a stock fuel rail.

On my race car that is fed with 2 -8 lines up front and 2 -8 returns on the rear, plugs no. 3 & 4 did run lean, but Cal has compensated for that with his tune in the XFI.

View attachment 181121

Nick, what plugs do you recommend for a 10sec 109?

 

[HelloBozos]

So powerplates do or don't help?

http://rjcracing.com/product/airflow-distribution-plate/

 

[dr_frankenstein]

my vot is for RPM + Detonation.

 

[ek02]

If the caps have metal transfer, detonation and cracked main webs would be a result. That may have allowed the stock crank to whip around like a wet noodle until it broke. This is the best job of engine destruction I have seen in a long time. It almost tops a Chrysler Hemi fuel motor I saw blow completely out of a funny car about 36 years ago, but the crankshaft was still in the car attached to the flywheel. I was standing next to Don Garlits when it was being towed clanking down the return road, crankshaft flopping around. He commented, "That boy done had the schnitzel ". Looks like that saying would apply here.

 

[turbonut85]

Can't wait to see this in person....

 

[INEEDAGN]

I would bet that if the balancer or the main webs were damaged first, it would make noise and/or vibrate for a long while before it let go (under regular highway driving). If the crank has signs of a growing stress fracture then it's the first failure point, if not, I vote hyper pistons to be at fault. I'm trying to visualize from the comfort of my chair, what kinda bind a connecting rod without a piston attached could get itself into.

Does the front half of the engine at least kinda sorta rotate still? If the crank went first, would the front half come to a stop so fast that it'd break the balancer and rip open the mains in such spectacular fashion? And would it rip the rod out of the piston (piston 6 is still hanging on)? I'm sure that if the piston went first and the rod caught something solid, it'd do everything pictured, in very short order. I'm not claiming to know anything, just thinking aloud.

 

[PaCemkr86]

Ok, here is the story id tell.
Was at the track.. 25 PSI launch on the transbrake.. Wheels up launch hit the rear bumper causing the rear wheels to get off the ground and then total over rev !!

 

[we4Mateo]

Ok, here is the story id tell.
Was at the track.. 25 PSI launch on the transbrake.. Wheels up launch hit the rear bumper causing the rear wheels to get off the ground and then total over rev !!

awesome!

 

[c n avoid87]

Ok, here is the story id tell.
Was at the track.. 25 PSI launch on the transbrake.. Wheels up launch hit the rear bumper causing the rear wheels to get off the ground and then total over rev !!

What game is this?

 

[turbonut85]

I would bet that if the balancer or the main webs were damaged first, it would make noise and/or vibrate for a long while before it let go (under regular highway driving). If the crank has signs of a growing stress fracture then it's the first failure point, if not, I vote hyper pistons to be at fault. I'm trying to visualize from the comfort of my chair, what kinda bind a connecting rod without a piston attached could get itself into.

Does the front half of the engine at least kinda sorta rotate still? If the crank went first, would the front half come to a stop so fast that it'd break the balancer and rip open the mains in such spectacular fashion? And would it rip the rod out of the piston (piston 6 is still hanging on)? I'm sure that if the piston went first and the rod caught something solid, it'd do everything pictured, in very short order. I'm not claiming to know anything, just thinking aloud.

If you were to stick a stock rod into a block, with a stock crank and no piston attached....you will see the rod is way to long to even come close to exiting the cylinder bore. If the piston let go first, (before the crank broke) it would just beat the ever living sh!t outta the cylinder.....my take from the pics is a bad crank sent over the edge by detonation....but as stated above....I will get to see it first hand this weekend.....

 

[turbonut85]

c n aviod87........love the color on your T!!!! looks alot like mine.....only nicer!!

 

[INEEDAGN]

If you were to stick a stock rod into a block, with a stock crank and no piston attached....you will see the rod is way to long to even come close to exiting the cylinder bore. If the piston let go first, (before the crank broke) it would just beat the ever living sh!t outta the cylinder.....my take from the pics is a bad crank sent over the edge by detonation....but as stated above....I will get to see it first hand this weekend.....

I was wondering that. Kinda figured it wouldn't make it outta the cylinder but might still bind up real good. Take some good pics of it when ya do get it.

 

[S10xGN]

I always loved this shot:

 

[pacecarta]

on up stroke the rod with pin will jam under the piston and will force the crank out of the block

 

[turbonut85]

on up stroke the rod with pin will jam under the piston and will force the crank out of the block

i don't doubtt that this is true....but from the pics I've seen....whats left of the piston is below the cylinder....and the crown seems to still be mostly intact....???

 

[turbonut85]

What power level? If the caps were walking the crank moving all over the place. It likely developed cracks before breaking. Usually you can hear some clicking or some other uncommon engine noise before it fails.

A normal person WOULD hear something.....my man Austin could not.....mostly due to the Rock Island anthem he had playing at volume level +346.............

 

[Spooling]

It let go under normal driving, but.......normal driving to Austin usually means peddle to the floor, stereo up as loud as possible

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I'd like to know what kinda Stereo he has installed

Seriously though - my bet is that the crankshaft was the source of this carnage.

Back in ~ 1983 I remember a 4.1 Litre 4BBL Buick V6 that had some warranty work done - replacing the crankshaft with a NA crank - and it broke right in half - causing the engine to sieze-up.

All of this happened under normal driving conditions as well.

 

[austinibew145]

Ok, I just read up on this thread. I like Polzins ability to type. He makes a hell of a lot more sense then I do. I think the torque converter is broke. Turbonut can verify this weekend. I saw some "parts" in the bottom of the converter. I don't know how much of the transmission is bad at this point. The case is broke. The key in the crank was not sheared off, but I could not slide the small timing gear off. I did send some pics in to car craft. I should of had Polzin type it up. I took some more picks I'll try to post here soon. Thanks for the input guys. The next build will be a cheaper one, for now. I don't think I can go as long as Polzin without driving. Or is it time to buy a second one...