Best piston for street/strip 340?

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Captainkirk

Captainkirk

Old School Mopar Warrior
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What do you guys consider the best piston (best price considered) for a street/strip 12 second 340?
I have heard some negative reviews on the Keith Black Hypereutectics shattering...although some or all of this could be internet rumor.
Wisecos are little bit outside my tax bracket
KB's..well, see above
Speed Pro?
Any others I may be overlooking?

10-11:1 compression range....
 
KB pistons are great pistons IF INSTALLED AND CLEARANCED CORRECTLY..... good price, much tighter piston to wall clearance is possible, and have nice valve pockets. Easy to get a good compression ratio without tons of milling. Lighter than factory pistons also.
 
replicaracer43 said:
KB pistons are great pistons IF INSTALLED AND CLEARANCED CORRECTLY..... good price, much tighter piston to wall clearance is possible, and have nice valve pockets. Easy to get a good compression ratio without tons of milling. Lighter than factory pistons also.
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Aren't the KB hypers cast pistons though?
 
Captainkirk said:
Aren't the KB hypers cast pistons though?
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Yes, but one comparison to the stockers, and you can see they are much stronger. Also, because they are lighter, they are easier on the rods and crank, especially if you compare them to old heavy forged dome top pistons. If they live in my circle track motors at 6800 rpm mostly wide open throttle, for HOURS they will live in any normal street inviroment almost forever. Well, wait, actually I do have a set of the KB243s in my street car that I built in 2002 and there are doing fine too....that's probally 80k miles by now. With KB pistons, its all in proper bore sizing, and PROPER RING GAPS.
 
replicaracer43 said:
Yes, but one comparison to the stockers, and you can see they are much stronger. Also, because they are lighter, they are easier on the rods and crank, especially if you compare them to old heavy forged dome top pistons. If they live in my circle track motors at 6800 rpm mostly wide open throttle, for HOURS they will live in any normal street inviroment almost forever. Well, wait, actually I do have a set of the KB243s in my street car that I built in 2002 and there are doing fine too....that's probally 80k miles by now. With KB pistons, its all in proper bore sizing, and PROPER RING GAPS.
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What is different in bore/ring sizing?
 
Captainkirk said:
What is different in bore/ring sizing?
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KBs can run tighter to the bore because of how they are made, material wise, and ring gaps are critical on them, they HAVE to be set correctly, thans where 99.9% of the horror storys with KB pistons come from. But its not the pistons fault, its the guy setting clearance and assembling the engine. As a comparison, the old TRW slugs are tough, but you need more skirt to wall clearance because they expand more from cold to warm.....KBs dont
 
KB failures come from idiots that do not follow instructions. They are good pistons. If you are too lazy to file fit rings, do not get them.
 
Or from guys who run lean at WOT or have too much timing. Detonation will kill any piston. Tune that carb correctly to achieve long life and max power. There are lots of guys running 500+ horsepower on stock pistons with a turbo. It's all in the tune. And as mentioned, installation.
 
KB probably most bank for the buck. I usually run the TRW/Speed Pro 2316s. Just a forged replacement piston for the earlier 340s. They are durable as hell, but VERY heavy. Im a creature of habit. Have built over 20 340s with them and never had any problems.
 
swinger340 said:
KB probably most bank for the buck. I usually run the TRW/Speed Pro 2316s. Just a forged replacement piston for the earlier 340s. They are durable as hell, but VERY heavy. Im a creature of habit. Have built over 20 340s with them and never had any problems.
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I see the "heavy" thing referred to those old forged pistons all the time. But I am not sure it's not much ado about nothing. I mean, I understand the advantage to a lighter slingin mass. Certainly it has it's advantages. But I've never seen a rash broken connecting rods and blowed up motors from the past using those type pistons. I think like with anything else, if it's machined properly, balanced good and assembled well, it will last just fine.
 
RustyRatRod said:
I see the "heavy" thing referred to those old forged pistons all the time. But I am not sure it's not much ado about nothing. I mean, I understand the advantage to a lighter slingin mass. Certainly it has it's advantages. But I've never seen a rash broken connecting rods and blowed up motors from the past using those type pistons. I think like with anything else, if it's machined properly, balanced good and assembled well, it will last just fine.
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Agreed,and then some. A good machinist, would like this pay check.
 
RustyRatRod said:
I see the "heavy" thing referred to those old forged pistons all the time. But I am not sure it's not much ado about nothing. I mean, I understand the advantage to a lighter slingin mass. Certainly it has it's advantages. But I've never seen a rash broken connecting rods and blowed up motors from the past using those type pistons. I think like with anything else, if it's machined properly, balanced good and assembled well, it will last just fine.
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Yeah. I believe the 2316s are around 735 grams, can get a hyper piston closer to 475-500 grams. If added with lighter rods the lighter spinning mass is what some people want. I have never had any problems with the heavy slugs and I pound the crap out of my poor little engines.
 
It's about lifespan and power output. Pushing heavier parts around takes more power, the quality control is not as precise which will affect output, and controlling the extra mass is more stress on the rod, crank, and block. So it comes down to what can do the job required for the least money, and the least weight. At least for me that's usually how I decide what to use.
For the OP - I'd run the KB hypers unless there is not a cost issue in which case any modern forging would be fine. I'd avoid the oldschool because there's a lot better stuff around for a little more money.
 
RustyRatRod said:
KB failures come from idiots that do not follow instructions. They are good pistons. If you are too lazy to file fit rings, do not get them.
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This is the main problem with them. You must follow directions. I have had them in my 340 for 20 years. I don't baby my car either. My 340 is 400+ horsepower. They are a good piston.

Fred B
 
I been running the speed pro hypers with the skirt coating for 15 years now maybe 12k miles. I run 11.2 and 200 cranking psi on the street with 93. They must be strong because I've been running on the razors edge of detonation and pre ignition for a LONG time!!!!
 
Captain,
FYI the KB 243's and 76cc X-heads my compression ended up at 8.98:1 which is good for today's gas.
 
I've run the KB hypers in a 500hp 340 stroker 10:75:1. Sprayed 100 hp shot of nitrous at them and have had no problems. Great piston for the price. As others here have said, follow the instructions and make sure to file fit the rings. I don't recommend using the nitrous with these pistons. They really aren't designed for it.
 
MAHLE Forged are good , and light , 12000mile on mine with no problems , lots of 7,000 rpm runs .
 
As several have said , The KBs are good if you gap the rings like they say. I had a set in a daily driver for six years , lots of miles . Now the same set are in my oldest son's 360 ,
been in there 2 years. The speed pro h116 is also a good piston .
 
mopar sam said:
as several have said , the kbs are good if you gap the rings like they say. I had a set in a daily driver for six years , lots of miles . Now the same set are in my oldest son's 360 ,
been in there 2 years. The speed pro h116 is also a good piston .
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this!!!!!!! ^^^^^^
 
Mopar Sam said:
As several have said , The KBs are good if you gap the rings like they say. I had a set in a daily driver for six years , lots of miles . Now the same set are in my oldest son's 360 ,
been in there 2 years. The speed pro h116 is also a good piston .
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Speed pro 116 is a360 piston not a 340
 
Been running Speed Pros in my 360 going on 3 seasons now..if you want to spend some money on really high quality Diamonds are my choice got them in the 416...
 
We run JE's in Are 408. Runs 11.50s and we drive it on the streets as much as we can. Paid around $500 for a set.
 
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