7 replies to this topic

[.998TANGO.]

i cant decide which pistons to buy for my 1293 engine project.

heres the two choices clicky or clicky

im drawn to the cheaper ones as im working with a small budget.

has anyone used either of these types?

thanks

[T.Harper]

Totally depends on spec and intended usage.

[.998TANGO.]

im going for general reliable road use,using piper 270 cam, and stage 1 kit everything else standard

is there any major advantages with the slipper piston?

thanks

[T.Harper]

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.minispare...=...GA 6CC DI...

This is similar to what you've got there:
http://www.minispare...=...75 LOW DR...

These have been popular in recent years:
http://www.minispare...=... 9.75CR 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.

[.998TANGO.]

thanks for the point in the right direction think im going for the middle one keep costs down for now

thanks elliot

[T.Harper]

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.

[01smartc]

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

Edited by 01smartc, 09 March 2010 - 10:59 PM.

[Cooperman]

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.