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High compression pistons

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Time for a new piston in my 03. Does anyone have any pros and cons on the pro circuit high compression piston?? I'm wanting a high compression piston and I want the best out there. It's going into a bbt head with sst valves.

Thanks guys.

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pro-circuit pistons are shelf items with a new box and insane price tag....

they wont even give any specs on them.... just have to believe in the tooth fairy and give them a blank check....

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Time for a new piston in my 03. Does anyone have any pros and cons on the pro circuit high compression piston?? I'm wanting a high compression piston and I want the best out there. It's going into a bbt head with sst valves.

Thanks guys.

Go with Wiseco.

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wrong...wiseco has been the worst performance piston mfgr of the last 4 decades....

if you want the best shelf pistons possible, there is no other choice than CP pistons...

if anyone wants to talk serious piston tech rather than just flag waving... lets hear what you guys think makes power in piston details

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wrong...wiseco has been the worst performance piston mfgr of the last 4 decades....

if you want the best shelf pistons possible, there is no other choice than CP pistons...

if anyone wants to talk serious piston tech rather than just flag waving... lets hear what you guys think makes power in piston details

The guy that works on my bike is the owner of JMD Pro Porting, has been in the business for 30 yrs. and swears by them. He is a top engine builder and backs up his work. I don't think he would use the worst piston for past 4 decades as you put it and back his work. Are you an engine builder, and what do you have to back your comment.

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CP pistons are better than Wiseco and JE. JE and Wiesco are partners.

CP (Carillio) are MUCH more beefy on the crown supports and they have better oiling of the piston pin. CP also has some type of anti detonation rings on the valve reliefs (who knows if they work). The skirts are wider on the CP and JE. I like the fact that Honda widened the 04+ cylinder skirt area(I can't remember if it was 04 or 05!).

You can use a 04+ cylinder on a 02-03 but the cylinder has to be ground/notched for the skirt oiler in the case.

JE pistons come with a spec sheet on measured dimensions(s) and weight for each piston.

I have used all 3 pistons without any harm. No catastrophic failures with any.

My money is on the CP piston. If I can't get a CP would choose JE. If no JE I would get a CP :smirk:

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i'm down with rocksalt's appraisal....

the Calvert brother's that started CP pistons are their own engineering group now...

they first worked as the engineering drive behind Arias pistons in the automotive world...

then they were the engineers that got JE pistons on the map...

then they got tired of being put in a "design box" and engineering stuff for everyone else and decided to start their own company so they could do what they do best without any limitations: engineer premium performance pistons...

and that's exactly what they do...!!

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i am the engine guy at Venom Performance... WWW.VenomPerformance.net...

and have worked with CP pistons engineers for all of Venom's custom application pistons for over five years....

does that count ??

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i am the engine guy at Venom Performance... WWW.VenomPerformance.net...

and have worked with CP pistons engineers for all of Venom's custom application pistons for over five years....

does that count ??

I'm in no position to argue with you since I know nothing about the subject. I do know that my buddy is well respected in the area and has been building high performance engines for a long time and he uses wiseco. I'm sure CP pistons are very good but I don't think he would use the worst piston in 4 decades. I will ask him. CP is what you guys use and like and that's great, but it doesn't mean everything else is garbage.

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wrong...wiseco has been the worst performance piston mfgr of the last 4 decades....

if you want the best shelf pistons possible, there is no other choice than CP pistons...

if anyone wants to talk serious piston tech rather than just flag waving... lets hear what you guys think makes power in piston details

...just for interested, could you give me tutorial explanation what makes power in piston details?

Thanks

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absolutely.... i type with 2 fingers so i will have to author it when i get a bit of time... soon

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I noticed they've got a 14:1 compression piston. Ever tried that beast out? It's a single ring piston so how would the durability be? I do know that I won't go no lower then the 13.5:1 compression piston. Is it wise to use race gas on such high compressions? Can I still use 93 octane? Or will race gas give me the best bang?

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compression ratio is the difference in volume between the piston at bottom of cylinder and top of cylinder.... i.e. 14:1 is 14 time smaller/tighter squeeze at top than at bottom...

once you get into race gas territory of 13:1 ish, you might as well go for tons of compression to get the most out of race fuel ...

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It all depends on what the piston manufacture is willing to do for the customer even though wiseco and J&E are owned by the same share holders dopes not make them the same company .i have used all the brands of pistons some work better than others in certain aplications the cps work well in the crf and trx aplications and seemed to work better in big bore aplications .the real hp comes from the ring groove acuracy and top ring suport i use J&E for all my proto type and race engines latley i have found some good results with the new wiseco pro pistons .im so old that i used arias pistons when the cp boys were still there i also used venolia pistons back when i needed customs for the 350x honda trikes.i also found the cp to work very well in the 2009crf 450.

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Efficient combustion makes power, not high compression. If higher compression make the combustion better then yes, but if the raised crown of the HC piston interfers with good combustion process ( especially at higher rpms) then no it's not better. More is not always better when your just simply bolting a piston in. There's a reason why the oem piston crowns and compressions are where they are. compromises were made, not saying you can't do better, but there is usually a reason.

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absolutely.... i type with 2 fingers so i will have to author it when i get a bit of time... soon

ain't a problem, whenever you want....thanks a lot

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