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Sun Jan 07, 2018 2:49 pm

I have a new 1776 build I am putting together and i have a set of Mahle 90.5 pistons.
There was a delay between fit up, tweaking and final assembly, and I threw the retaining clips away with the box :roll:

What clips originally come with their piston sets? I need a full set of 8.

Thanks!

Sun Jan 07, 2018 3:26 pm

Depending on piston type, you could use Teflon buttons... I forgot why the piston style name is that they will NOT WORK with though... Someone soon will help me to remember...

EDIT TO ADD: Not recommended for "slipper skirt pistons"..

Dale

Sun Jan 07, 2018 3:27 pm

All the stock and mahle piston sets use the same round wire clips.
some people would never re-use an old clip, and that may be a good policy.......but you can. If they look OK and seem to have the right tension and so forth, then they they probably are fine.

you can also use tru-arc c-clips, I think berg started that. ACN sells those.
Square clip in a round groove is kinda screwy but it does work fine.

Sun Jan 07, 2018 4:11 pm

any ACVW store should carry them. No matter the build with Mahle pistons, I use Tru arcs. 5-6 bucks.

Sun Jan 07, 2018 4:38 pm

Teflon buttons don't normally work with the slipper skirts. but I've seen someone selling aluminum extensions that go in the piston and then the buttons go in the extension for slipper skirts.

Sun Jan 07, 2018 6:42 pm

Ebel wrote: Teflon buttons don't normally work with the slipper skirts. but I've seen someone selling aluminum extensions that go in the piston and then the buttons go in the extension for slipper skirts.

Teflon buttons WILL fall out of slipper skirt pistons. The Teflon needs to ride against the cylinder. The extension idea sounds kinda sketchy to me, I'd stick to wire locks.

Sun Jan 07, 2018 8:38 pm

I put teflon buttons in my first engine rebuild. They trap oil in the pins though so I wouldn't bother with a balance job if you go this route :/

Sun Jan 07, 2018 9:06 pm

I've used the buttons before and had no issues...at least you can't snap a button loose, lol...but have heard of clips popping out and causing serious cylinder damage.

VeeWeeman

Sun Jan 07, 2018 11:23 pm

I use TruArc on anything that comes with stock wire clips and chuck the clips. I have seen to many wire clips come out. Spiral Locks on any race motors I put slipper skirts in. I have installed a few Teflon just to see how they'd turn out but decided they weren't for me.

Sun Jan 07, 2018 11:40 pm

I drill a hole in the center of my teflon buttons so it goes on easier but i got spiral locks on my other pistons and I jus like many and wonder if da ting going come out.

Mon Jan 08, 2018 12:17 am

Tru Arc is all I use.
I've seen what the Teflon buttons can do. Nope, not for me.

Mon Jan 08, 2018 12:49 am

The main cause of clips coming out is tweaked rods.
Checking connecting rod alignment is part of any engine rebuild, yet often not done, instead pins are removed by hammering.....
yikes

Mon Jan 08, 2018 5:30 am

If using true arc clips.. there is a side with sharp edges, and the other will have dull edges. It's not hard to see when you look closely, probably a result of the manufacturing process; one side has blunt rolled edges. You want the sharp edges facing out, and the blunt edge towards the pin.

Mon Jan 08, 2018 6:20 pm

UK Luke 72 wrote: I put teflon buttons in my first engine rebuild. They trap oil in the pins though so I wouldn't bother with a balance job if you go this route :/
Unless, of course, every pin gets the same amount of oil trapped in it, in which case you're back in business! :P

I've had a wire clip come loose and destroy a cylinder before, so I decided to give the Teflon buttons a try on my latest build. They only weigh about six grams apiece, and they're easy to shave down, so you can use them to balance the pistons really tight, and that's kinda nice.

I've had them in for about five years now and I haven't noticed anything unpleasant. I have heard some people say there is a chance of carbon particles getting trapped in the soft Teflon and scratching the hell out of the cylinder walls as the piston goes up and down. I suppose it's possible, but I've never seen any actual proof, so you'll have to decide for yourself if it's worth the risk.

I accepted the risk, so if it happens to me, I promise I'll take plenty of pictures and post them up.

Tue Jan 09, 2018 8:57 am

veeweeman wrote: I've used the buttons before and had no issues...at least you can't snap a button loose, lol...but have heard of clips popping out and causing serious cylinder damage.

VeeWeeman

ive experienced this first hand... its pretty gnarly... you end up producing an oil fog behind your vehicle ... so much fun

Tue Jan 09, 2018 9:11 am

I used Teflon buttons for years. My 1776 had them for 15 year. I had it apart twice for maintenance (autocross racer and daily driver) and never ever saw a trace of oil inside the piston pin or wear on the cylinder walls caused by the buttons.

I use Bugpack c-clips now in all my engines as they are lighter than buttons or don't fit slipper skirts like in my big engine.

brad

Tue Jan 09, 2018 10:57 am

I've had the Teflon buttons, but decided not to use them because of the extra weight they add. You reduce the weight on that end of the rod. And I'm talking about a high performance engine. They would be fine on a mild or stock engine.

Tue Jan 09, 2018 11:35 pm

I used teflon buttons for more than 30 years on all my engines and i did a lot of racing and never a problem and the weight thing is trivial but the balance thing is a good idea. they are so easy to put on and take off, jus pop it in and pop it out. So first hand after 30 years, i never had a problem with it but my new slipper skirt ones is a whole new thing trying to get it in and then latter take it out.

Thu Jan 11, 2018 7:10 pm

the teflon dont hurt squat, but if they do it wasent thier fault. :shock: I use them I like them. although...there are some issues.I have started drilling them for oil release or using the 94 butons for the smaller pistons and machining them for a tight fit.I think cb now has diferent ones for the l/w pins...I think they have been out for 7 years or so...I may have a set or 2 but i have somany sets of 94'teflon bugpoops i got a deal on I machine them to fit the smaller pistons. my trick race pistons have wire locks...and tool steel dellwest casidium pins that are less than 1.8"long...so no buttons.all my mahles have buttons, and have never left a mark on the walls.

Thu Jan 11, 2018 7:46 pm

I use Spiral Locks. Total pain in the ass but they ain't coming out.