Teflon button question
Turbo Mini Forums

Hiya i have been collecting parts for an turbo engine build and the pistons i was going to use are circlip type not a problem i was going to make some teflon buttons. But i was reading an article the other day that dosent recommend them for road engines as the life span is short. The article said it had seen some worn to excess in under 1000 miles and they pollish the sides of the bores which damaged the rings.
Im not after an engine that will last forever but dont want to take it appart every 1000miles. My question is to anyone running them what sort of life span have they found they last and any signs of bore wear.
Thanks James

My small bore turbo project http://www.turbominis.co.uk/forums/index.php?p=vt&tid=473901

Exactly what pistons are they, if theyre the newer Omegas the circlips or wire rings are sufficient

I seriously doubt it!

hiya cheers for your quick reply. They are actually used standard pistons that are very low milage so i was going to re ring them. they are 1098cc pistons. i know i could post in the 998 section but i though the teflon button question is general cheers james

My small bore turbo project http://www.turbominis.co.uk/forums/index.php?p=vt&tid=473901

Ah, tbh I have no experience of those pistons

I seriously doubt it!

I've had mine in for probably 10,000 miles or more with no problems so far. they have slightly polished the bores, but I'm not sre it's a big isue.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

ok cheers 10,000 miles slight bore mark i can handle.

My small bore turbo project http://www.turbominis.co.uk/forums/index.php?p=vt&tid=473901

I've had a set fitted for probably over 5-6 years now. Probably only covered around the same mileage as Wil though.

WWW.TURBO-MINI.COM

I did 6000 miles in one year and never had a problem, never noticed they polished the bore where they ran. TBH that was the least of my worries lol.

The buttons I used were rather thin too, the pins were the longer type.

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Edited by Sprocket on 29th Feb, 2012.

In a 1098 engine I'd use the original circlips...

I wouldn't, I had a circlip get out on a 1098 +020 engine build and wreck the block. This was many years ago as an impressionable 18 year old who knew nothing about teflon buttons.

I'm using original Cooper raised D pistons with circlips in a 998 race engine. No problems. I'm not saying it couldn't happen, but I don't fear it if installed correctly.

I said the other week I was chatting to an engine builder who prefers to use circlip pistons over press fit.
But it's each to their own from the advise given or through own personal experience, when I do come to strip and rebuild my 998 I'm undecided what to do.

one day boost will be mine!

You will only have a circlip get out once before you will never use them again.

Depends very much on the intended use of the engine. Purely from an engine building perspective, circlips are a lot easier. But not suitable for an engine seeing high revs regularly.

As discussed before:

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=304197

Going over 6k, then use buttons.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I suppose once it's stripped and Ive spent X amount on pistons and machining etc it would be buttons that went in, if the risk with circlips is small but the risk with buttons is none then it has to be buttons.

one day boost will be mine!