Please be careful when answering peoples technical questions that you do not misguide them into taking inappropriate action.
Not only is this annoying, but it can also be costly and could even be dangerous if the wrong information is given.
This is why we ask that only first-hand and factual information is posted in reply to peoples queries.
If you are not 100% certain of your reply, be sure to point out your uncertainty.
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Mar 9 2010, 09:35 PM
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#1
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Mini Mad ![]() ![]() ![]() ![]() Group: Members Joined: 14-August 09 From: eastbourne |
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Mar 9 2010, 10:20 PM
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#2
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Super Mini Mad ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Joined: 9-February 08 From: Kent |
Totally depends on spec and intended usage.
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Mar 9 2010, 10:26 PM
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#3
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Mini Mad ![]() ![]() ![]() ![]() Group: Members Joined: 14-August 09 From: eastbourne |
im going for general reliable road use,using piper 270 cam, and stage 1 kit everything else standard (IMG:style_emoticons/default/sideways.gif)
is there any major advantages with the slipper piston? thanks |
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Mar 9 2010, 10:36 PM
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#4
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Super Mini Mad ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Joined: 9-February 08 From: Kent |
Not really for road use. You want something that's reliable for the road, and that can handle your compression ratio.
A full skirt is desirable for reliability but comes at a price: http://www.minispares.com/Product.aspx?ty=...GA%206CC%20DI... This is similar to what you've got there: http://www.minispares.com/Product.aspx?ty=...75%20LOW%20DR... These have been popular in recent years: http://www.minispares.com/Product.aspx?ty=...%209.75CR%20+20 Above all, you need to decide on a compression ratio to go with that cam, and then decide on a capable piston from there really (depending on dish size and intended chamber size). I can't help you with that, but I reckon you'll probably end up with one of the above. Best consult an engine builder on here or working for one of the suppliers. |
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Mar 9 2010, 10:44 PM
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#5
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Mini Mad ![]() ![]() ![]() ![]() Group: Members Joined: 14-August 09 From: eastbourne |
thanks for the point in the right direction (IMG:style_emoticons/default/thumbsup.gif) think im going for the middle one keep costs down for now (IMG:style_emoticons/default/sideways.gif)
thanks elliot |
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Mar 9 2010, 10:56 PM
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#6
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Super Mini Mad ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Joined: 9-February 08 From: Kent |
I'd recommend asking someone first. I've not been on here a while so I don't know who's in the engine building business. You just need to ask someone what compression ratio you should be looking at with that cam, then you can work out what pistons and dish size you'll need from the CR calculation and head combustion chamber size.
You may need to go for a piston capable of higher compression because of your cam choice. |
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Mar 9 2010, 10:57 PM
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#7
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One Carb Or Two? ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Traders Joined: 17-December 05 From: Tamworth ... Staffodshire |
We always use the 21253 pistons in our engines.. good quality for fast road.
The 21251 are good enough on a lower budget. Just re-read.. i'd sway towards the 21253 as your going to be running around 9.5-10:1 compression with that cam (i assume?) Chris @ Smart Performance This post has been edited by 01smartc: Mar 9 2010, 10:59 PM |
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Mar 10 2010, 12:32 PM
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#8
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Up Into Fourth ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Joined: 13-March 04 From: Earith, Cambs Member of a Local Club?: MCR, HAMOC, Chelmsford M.C. |
I always use the Hepolite 21253 piston. It is a 'slipper' low-drag type with good oil return slots as opposed to the cheaper ones whih have long oil drain slots. Thus the 21253 is much stronger as well as giveng a higher basic compression ratio.
I have used these in competition cars over the years with no failures whatsoever despite using sustained revs of up to 7000 rpm. Also they seem OK at high compression ratios of up to just over 11:1 if you want to go that high. They do represent a really good cost/performance/strength option. Excellent value. |
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Lo-Fi Version | Time is now: 31st July 2010 - 07:14 PM |