Replacing pistons

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skinnydog0_0
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Replacing pistons

Post by skinnydog0_0 » Wed Dec 01, 2010 11:13 pm

Hi All,

I have 2 new pistons from a previous job that i haven't used, and am thinking about replacing the used ones i have in the engine.
The new ones are brand new 35 ones;
the old ones are 30 ones.

My question is - in an ideal world i would have the barrels honed when the new pistons and rings are fitted, but is this essential?
if you think it is, where would you recomend having the honing done?
I have heard that SEP in Kegworth are good any thoughts on these guys or any others?

Thanks in advance

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trademe900
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Re: Replacing pistons

Post by trademe900 » Thu Dec 02, 2010 12:12 am

Sorry, just wondering- what's wrong with your pistons?

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Cammo
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Re: Replacing pistons

Post by Cammo » Thu Dec 02, 2010 1:20 am

skinnydog0_0 wrote: I have 2 new pistons from a previous job that i haven't used, and am thinking about replacing the used ones i have in the engine.
The new ones are brand new 35 ones; the old ones are 30 ones.
Sorry to be a bit thick, but does that mean you'd be running 2 x nc30 and 2 x nc35? If so that probably wouldn't be a great idea.
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Re: Replacing pistons

Post by karl BKK » Thu Dec 02, 2010 4:41 am

New pistons and rings = honing mate.
Your old rings would have worn to the cylinder walls, your new rings won't be destroyed but you'd be better off honing if you want everyhting to mate up nicely :)
And the question has to be asked again, just because you have two shiney new pistons why would you want to change them? :)

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skinnydog0_0
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Re: Replacing pistons

Post by skinnydog0_0 » Thu Dec 02, 2010 7:33 am

Yer sorry guys, didn't explain very well.
I plan on replacing all of them with new 35 ones. I understand that the 35 pistons are slightly better than the 30 ones?
Also they are to go into my race engine so am looking for a power increase, but if it is going to cost loads of bucks, then i will look at spending my cash in other areas.
Thanks :peace:
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karl BKK
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Re: Replacing pistons

Post by karl BKK » Thu Dec 02, 2010 9:33 am

if you don't need the pistons the money would be better spent else where mate, carb tune up, exhaust system, brakes, suspension etc etc :)

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Cammo
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Re: Replacing pistons

Post by Cammo » Thu Dec 02, 2010 11:10 am

The 35 pistons are better, but I don't think you'll notice a gain in power, everything little bit adds up I spose.

Probably not worth pulling it apart unless it really needs it!
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Drunkn Munky
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Re: Replacing pistons

Post by Drunkn Munky » Thu Dec 02, 2010 11:25 am

Yeah wouldnt be a good idea running 2x 30 and 2 x 35 pistons, save up and do all 4. is it worth doing???? well it can only make it better but doubt your notice it. Id do it tho if i had the pistons along with some hot cams while im in there :grin:

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skinnydog0_0
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Re: Replacing pistons

Post by skinnydog0_0 » Thu Dec 02, 2010 6:04 pm

Thanks for the advice guys, much appreciated.
I think i will leave the piston change till the end of the season and a full refresh.
I will save my cash and get some spare tyres, or do a few trackdays perhaps.

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