New crate engine is now a steam engine....bad problem...
Safety Car
Joined: Apr 2004
Posts: 3,997
Likes: 1
From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by luerja
From: MsVetteMan
Picking the motor up around lunch and taking it to an actual performance engine builder (vrs. a machine shop) and going to let them take a quick look at it. Just want to get another opinion before I ship it back to Marshall.
Thanks for the support guys, and I'll let you know what the 4th party inspection reveals.
MsVetteMan
Picking the motor up around lunch and taking it to an actual performance engine builder (vrs. a machine shop) and going to let them take a quick look at it. Just want to get another opinion before I ship it back to Marshall.
Thanks for the support guys, and I'll let you know what the 4th party inspection reveals.
MsVetteMan
Melting Slicks
Joined: Dec 2004
Posts: 2,101
Likes: 3
From: Cruising somewhere in St. Louis, Missouri
Originally Posted by MEGALADON
DUDE, did he really get time off!!!
Yes...They put him in the corner for 10 days...
Only through covert operations and underground tunnels we are able to get a couple messages out to respond to questions.
Jim
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Melting Slicks
Joined: Dec 2004
Posts: 2,101
Likes: 3
From: Cruising somewhere in St. Louis, Missouri
From: MsVetteMan
Okay....finally tracked down a "big time" honest/expensive/fair performance engine builder here to take a look. Of course his work was simple and the pistons were already out. (no charge by the way).
First thing he pointed to were the Keith Black pistons and he shook his head in disgust. I gave him my ring gap measurements, and he said that doesn't matter if they are correct with those pistons. Quote: "What happened to you is exactly why we don't ever use those pistons".
Basically he was saying they are crap.......and you are taking your chances with them, proper ring gap or not. Makes you wonder if the ring gap theory is just a coverup for KB's continuous problems and reputation?
He basically agreed that it wasn't detonation. His version is the ring land broke first, then it broke the cylinder. Then the broken pistons got sucked over from #6 to #3 and broke that ring land. They weren't suprised or confused at all about what they were looking at. Also the sides of the pistons were pretty clean which indicates it was not from detonation.
Guess whose doing my 383 stroker rebuild from my original block??
Engine is in the garage (in parts). Gotta put it back together and ship it back to Marshall engines.
MsVetteMan
Okay....finally tracked down a "big time" honest/expensive/fair performance engine builder here to take a look. Of course his work was simple and the pistons were already out. (no charge by the way).
First thing he pointed to were the Keith Black pistons and he shook his head in disgust. I gave him my ring gap measurements, and he said that doesn't matter if they are correct with those pistons. Quote: "What happened to you is exactly why we don't ever use those pistons".
Basically he was saying they are crap.......and you are taking your chances with them, proper ring gap or not. Makes you wonder if the ring gap theory is just a coverup for KB's continuous problems and reputation?
He basically agreed that it wasn't detonation. His version is the ring land broke first, then it broke the cylinder. Then the broken pistons got sucked over from #6 to #3 and broke that ring land. They weren't suprised or confused at all about what they were looking at. Also the sides of the pistons were pretty clean which indicates it was not from detonation.
Guess whose doing my 383 stroker rebuild from my original block??
Engine is in the garage (in parts). Gotta put it back together and ship it back to Marshall engines.
MsVetteMan
Instructor
Joined: Aug 2005
Posts: 209
Likes: 8
From: Hollywood FL
Originally Posted by luerja
From: MsVetteMan
First thing he pointed to were the Keith Black pistons and he shook his head in disgust. I gave him my ring gap measurements, and he said that doesn't matter if they are correct with those pistons. Quote: "What happened to you is exactly why we don't ever use those pistons".
Basically he was saying they are crap.......and you are taking your chances with them, proper ring gap or not. Makes you wonder if the ring gap theory is just a coverup for KB's continuous problems and reputation?
First thing he pointed to were the Keith Black pistons and he shook his head in disgust. I gave him my ring gap measurements, and he said that doesn't matter if they are correct with those pistons. Quote: "What happened to you is exactly why we don't ever use those pistons".
Basically he was saying they are crap.......and you are taking your chances with them, proper ring gap or not. Makes you wonder if the ring gap theory is just a coverup for KB's continuous problems and reputation?
Burning Brakes
Joined: Feb 2005
Posts: 894
Likes: 91
Cast (Hypereutectic) Pistons
Kind of goes back to my earlier answer in this post here and I do stand by my original statement (below), these pistons have no place in the performance playing field. If you're using them and NOT breaking them, you aren't making any power! Thanks, Gary in N.Y.
P.S. You may get by in a stock low power rebuild, but that's about it. And I wouldn't trust them even in that position. It may have to do with "quality control", as far as I know "Mahle" was making G.M.'s hyper-eutectic (cast) pistons and could possibly be a better piece than the KB's.
(Quote)
P.S. We do have 3 rules we adhere to strictly on "performance" units:
1-Don't ever use hyper-eutectic pistons.
2-Don't ever use hyper-eutectic pistons.
3-Don't ever use hyper-eutectic pistons.
(End Quote)
P.S. You may get by in a stock low power rebuild, but that's about it. And I wouldn't trust them even in that position. It may have to do with "quality control", as far as I know "Mahle" was making G.M.'s hyper-eutectic (cast) pistons and could possibly be a better piece than the KB's.
(Quote)
P.S. We do have 3 rules we adhere to strictly on "performance" units:
1-Don't ever use hyper-eutectic pistons.
2-Don't ever use hyper-eutectic pistons.
3-Don't ever use hyper-eutectic pistons.
(End Quote)
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
Originally Posted by GOSFAST
as far as I know "Mahle" was making G.M.'s hyper-eutectic (cast) pistons and could possibly be a better piece than the KB's.
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
Originally Posted by GOSFAST
P.S. We do have 3 rules we adhere to strictly on "performance" units:
1-Don't ever use hyper-eutectic pistons.
2-Don't ever use hyper-eutectic pistons.
3-Don't ever use hyper-eutectic pistons.
(End Quote)
1-Don't ever use hyper-eutectic pistons.
2-Don't ever use hyper-eutectic pistons.
3-Don't ever use hyper-eutectic pistons.
(End Quote)
I used the TRW forged pistons on 2 different rebuilds and broke them both times. The piston side skirts would break off and make a hell of a racket. The piston had an oil slot instead of holes which made them very weak.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by luerja
From: MsVetteMan..... His version is the ring land broke first, then it broke the cylinder. Then the broken pistons got sucked over from #6 to #3 and broke that ring land. MsVetteMan
how is this happening? are they saying that during the valve overlap when the exhaust valve in number #3 is still open a little during the intake stroke it gets sucked in?? or am i missing something obvious
Melting Slicks
Joined: Dec 2005
Posts: 2,441
Likes: 0
Originally Posted by luerja
First thing he pointed to were the Keith Black pistons and he shook his head in disgust. I gave him my ring gap measurements, and he said that doesn't matter if they are correct with those pistons. Quote: "What happened to you is exactly why we don't ever use those pistons".
Basically he was saying they are crap.......and you are taking your chances with them, proper ring gap or not. Makes you wonder if the ring gap theory is just a coverup for KB's continuous problems and reputation?
Last edited by shafrs3; Mar 17, 2006 at 10:07 PM.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Originally Posted by GOSFAST
If you're using them and NOT breaking them, you aren't making any power! Thanks, Gary in N.Y.
http://media.putfile.com/MiniRat-Dyno-546HP
Safety Car
Joined: Apr 2004
Posts: 3,997
Likes: 1
From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Melting Slicks
Joined: Dec 2004
Posts: 2,101
Likes: 3
From: Cruising somewhere in St. Louis, Missouri
Originally Posted by bobs77vet
how is this happening? are they saying that during the valve overlap when the exhaust valve in number #3 is still open a little during the intake stroke it gets sucked in?? or am i missing something obvious
In reply to Bob.....There were bits and pieces of the shattered piston top all in the oil pan bottom. Obviously they can be sucked into the intake and exhaust. Good thing was I didn't find anything else.