Strongest, best designed pistons for 15+ psi?
#1
TECH Enthusiast
Thread Starter
Join Date: Dec 2001
Location: Dublin, CA
Posts: 548
Likes: 0
Received 0 Likes
on
0 Posts
Strongest, best designed pistons for 15+ psi?
What are the best pistons for high boost applications?
I broke uncoated Diamond forged with detonation when I overboosted by 3psi.
I broke Mahle forged pistons before I even got home with 1/2 throttle and less than 10psi due to their design (they have no quench deck).
What's best for high boost street application? I'd like a good piston design for a 6.125" rod with:
Suggestions?
I broke uncoated Diamond forged with detonation when I overboosted by 3psi.
I broke Mahle forged pistons before I even got home with 1/2 throttle and less than 10psi due to their design (they have no quench deck).
What's best for high boost street application? I'd like a good piston design for a 6.125" rod with:
- strong ring lands
- not too much flycutting or deep top ring down distance
- good quench deck
- about -9cc or more dish
- top and side coatings
- full floating pin
Suggestions?
#4
TECH Enthusiast
Thread Starter
Join Date: Dec 2001
Location: Dublin, CA
Posts: 548
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by mattr228
make sure your compression height is suitable for your application
#5
Banned
iTrader: (8)
Join Date: Jan 2004
Location: Western New York
Posts: 375
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by blu00rdstr
What are the best pistons for high boost applications?
I broke uncoated Diamond forged with detonation when I overboosted by 3psi.
I broke Mahle forged pistons before I even got home with 1/2 throttle and less than 10psi due to their design (they have no quench deck).
What's best for high boost street application? I'd like a good piston design for a 6.125" rod with:
Suggestions?
I broke uncoated Diamond forged with detonation when I overboosted by 3psi.
I broke Mahle forged pistons before I even got home with 1/2 throttle and less than 10psi due to their design (they have no quench deck).
What's best for high boost street application? I'd like a good piston design for a 6.125" rod with:
- strong ring lands
- not too much flycutting or deep top ring down distance
- good quench deck
- about -9cc or more dish
- top and side coatings
- full floating pin
Suggestions?
Originally Posted by mattr228
Wiseco / JE / Ross ...... personally i would of stayed away from both of those your just listed
make sure your compression height is suitable for your application
make sure your compression height is suitable for your application
#6
TECH Veteran
iTrader: (21)
I would have to point fingers at the tune also. Detonation would have killed any piston if sustained long enough. Best thing to do is, get your new pistons and specify that they are for a blower application. The coatings will help also. FWIW, the GM MLS gaskets are .064, not .045.
#7
TECH Enthusiast
Thread Starter
Join Date: Dec 2001
Location: Dublin, CA
Posts: 548
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by JnJSpdShop
I know W2W made 1200 hp with these pistons also.
The problem I have with the Mahle pistons, is that I discovered they have no quench deck. Below is a pic of a Mahle Forged -9cc piston which is fully dished, and of LS1 heads. You can see where the quench deck is on the head, but there's nothing matching that on the Mahle design. Here's an article on quench: http://chevyhiperformance.com/techarticles/94138/
Trending Topics
#8
TECH Enthusiast
Thread Starter
Join Date: Dec 2001
Location: Dublin, CA
Posts: 548
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Beast96Z
I would have to point fingers at the tune also. Detonation would have killed any piston if sustained long enough. Best thing to do is, get your new pistons and specify that they are for a blower application. The coatings will help also. FWIW, the GM MLS gaskets are .064, not .045.
#9
TECH Veteran
iTrader: (21)
Originally Posted by blu00rdstr
I think those were the Mahle Turbo pistons, which are different from Mahle forged.
The problem I have with the Mahle pistons, is that I discovered they have no quench deck. Below is a pic of a Mahle Forged -9cc piston which is fully dished, and of LS1 heads. You can see where the quench deck is on the head, but there's nothing matching that on the Mahle design. Here's an article on quench: http://chevyhiperformance.com/techarticles/94138/
The problem I have with the Mahle pistons, is that I discovered they have no quench deck. Below is a pic of a Mahle Forged -9cc piston which is fully dished, and of LS1 heads. You can see where the quench deck is on the head, but there's nothing matching that on the Mahle design. Here's an article on quench: http://chevyhiperformance.com/techarticles/94138/
#10
TECH Enthusiast
Thread Starter
Join Date: Dec 2001
Location: Dublin, CA
Posts: 548
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Beast96Z
I'm confused as to what your trying to say. Your pistons are out of the hole, just like all LS-1's. I'm trying to figure out what you mean by quench deck on the heads matching the pistons. That's somewhat confusing.
If you are building an engine with steel rods, tight bearings, tight pistons, modest RPM and automatic transmission, a .035" quench is the minimum practical to run without engine damage. The closer the piston comes to the cylinder head at operating speed, the more turbulence is generated. Turbulence is the main means of reducing detonation....A running quench height in excess of .060" will forfeit the benefits of the quench head design and can cause severe detonation. - http://racingarticles.com/article_racing-10.html
Last edited by blu00rdstr; 10-31-2005 at 12:16 AM.
#11
Launching!
iTrader: (10)
Join Date: Dec 2004
Location: GI, NE
Posts: 287
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by blu00rdstr
How do you do that? I had .045" GM MLS gaskets, which is good for pistons with a zero deck height. Rocked and cold, the Mahle pistons have a max of .0237", so half that is .012" deck height(rounding up). That leaves .033" clearance, correct? I've read that .040 is close for steel rods, and .060" is close for aluminum rods.
give the guys at J/E a call and see what they ultimately reccomend
Last edited by mattr228; 10-31-2005 at 12:19 AM.
#15
TECH Veteran
iTrader: (21)
You can get away with the .033 quench in a mild application. People run LS-1's pretty tight these days. As long as your static compression is ok and the tune is good, you should have been able to go with .033. Personally, I wouldn't run it that tight. I aim for about .040 to be on the safe side. I still don't know what is up with the GM gasket thicknesses. The MLS's are spec'd at .064 from GM, but yours obviouslly measured thinner. On your next round, I reccomend using a Cometic .054". At least you know your problem won't lye in the gasket thickness. Was there something in the head desighn of the Mahle that was diffrent from your Diamonds? I'm still trying to figure how you said there was no quench deck. A pic might help. You should also measure your deck height with a dial indicator on th eblock. Using the math might get you close, but the only true way to know is to measure it in in the block.
#16
TECH Enthusiast
Thread Starter
Join Date: Dec 2001
Location: Dublin, CA
Posts: 548
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Beast96Z
You can get away with the .033 quench in a mild application. People run LS-1's pretty tight these days. As long as your static compression is ok and the tune is good, you should have been able to go with .033. Personally, I wouldn't run it that tight. I aim for about .040 to be on the safe side. I still don't know what is up with the GM gasket thicknesses. The MLS's are spec'd at .064 from GM, but yours obviouslly measured thinner. On your next round, I reccomend using a Cometic .054". At least you know your problem won't lye in the gasket thickness.
Originally Posted by Beast96Z
Was there something in the head desighn of the Mahle that was diffrent from your Diamonds? I'm still trying to figure how you said there was no quench deck. A pic might help.
Originally Posted by Beast96Z
You should also measure your deck height with a dial indicator on th eblock. Using the math might get you close, but the only true way to know is to measure it in in the block.
Last edited by blu00rdstr; 11-01-2005 at 11:44 PM.
#18
Banned
iTrader: (8)
Join Date: Jan 2004
Location: Western New York
Posts: 375
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by blu00rdstr
I think those were the Mahle Turbo pistons, which are different from Mahle forged.
The problem I have with the Mahle pistons, is that I discovered they have no quench deck. Below is a pic of a Mahle Forged -9cc piston which is fully dished, and of LS1 heads. You can see where the quench deck is on the head, but there's nothing matching that on the Mahle design. Here's an article on quench: http://chevyhiperformance.com/techarticles/94138/
The problem I have with the Mahle pistons, is that I discovered they have no quench deck. Below is a pic of a Mahle Forged -9cc piston which is fully dished, and of LS1 heads. You can see where the quench deck is on the head, but there's nothing matching that on the Mahle design. Here's an article on quench: http://chevyhiperformance.com/techarticles/94138/
Having a large quench isn't what killed these pistons, it was your tune or incorrect installation
BTW factory LT1 engines had a hugh quench area, .060"+ and they ran excellent
#20
TECH Senior Member
iTrader: (21)
Originally Posted by Phil99vette
Honestly you need to address your fuel system and tune before you start throwing money @ your shortblock. Spend alittle money there and you will be happy in the long run.
Phil
Phil
Exactly ...... u even said so yourself.... detination killed your first pistons........ my first thought would of been get rid of the detination... not the pistons........
Sounds to be the tune is way off and its one of the most importnat things.....