pistons?
Turbo Mini Forums

just found these on minispares website http://www.minispares.com/web/Item/P21251%2D00/InvDetail.cfm do you reckon they'd be suitable for a turbo engine? one of the rings has gone on my engine and seeing as i cant afford a full rebuild just yet will these do to replace the ones ive got in there seeing as they give 8.8cr?

Cheers, Nick.

They aint a very good for alot of power put it that way, theres a reason theyre cheap

They dont have a very large dish and achieve low compression by having a shorter distance between the gudgeon pin and the top of the piston, fitted in a normal 1275 they are a few mm down the bore at top dead centre. Not good for squish, making them more suseptable to detonation. Id say theyre ok to around 100 brake, Mine lasted along time with 90hp naturally aspirated but with 130 bhp one broke.

The engineer at Minisport reconned theyre crap. depends on theyre usage really

i might give them a try then, as long as they last me untill i've saved enough money to get a decent engine built up anyway. plus i'm only running 4.5psi on a standard engine so i'm lucky if i'm touching anywhere near 75bhp.

if i do fit them its gonna be the first time i've stripped down an engine so it'll be worth the ?60 just to learn how to take things apart and re-assemble em.

Cheers, Nick

I recon theyd last along time with that sort of power, they'll be fine

cool, cheers for the info dude. is there anything else thats fairly cheap worth replacing while i have it in pieces? or what parts other than gaskets are a must to replace?

worn out bits. Diff pin is one thing id change, otherwise just tierd parts. If it aint broke!
Other people may have some suggestions,

Phil

Before you order ask if they have a slot or holes behind the oil control ring.
If slot, fine, but don't ever go over 5500 rpm or 100hp!

Arent these +40?

Just wondering as obviously the more you take out the block the less options you have for later rebuilds

Just dont rev them!

Limit yourself to 5k and they will last a good long time!

alex

AlexF

PMSL, 3 years dude!!!

I ain't the chief fer nuthin!

PMSL..

Vergard you deserve the award for digging up the oldest posts..lol

EDIT: just read the comment under your pic..lol

Edited by matty on 15th Aug, 2007.

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

i love the way Vegard responded to the question like it was asked today

Back once again like a renegade master

I read some where that the standard Rover A+ piston was good for 8500rpm as long as they are replaced frequently, and that was on Miglia builds, slots and all.

mind you they are a different kettle of fish

Edited by Sprocket on 15th Aug, 2007.

21251 pistons aint the greatest: they were fitted into marina vans and such like and designed for low compression 'shopping trolly' work (not a great deal of strength in them)..

there is a massive groove that joins the crown to the skirt of the piston.

nick - will bring you a 21251 and a 21253 to Oulton at the weekend and you can judge for yourself... but i wouldnt like them in a turbo tbh... especially with your right foot

Edited by icklemini on 15th Aug, 2007.

dave, this threads about 3 years old dude

I've been using the 21253's since i posted this all them years ago, lol

Vegard having a flashback?? :s

could bring up a melted 21253 then if you like..

yup, vegard is the chief ancient post excavator

don;t bring me any melted pistons please, i'm worried enough with it running how it is at the moment, pinking its nuts off at anything over 10psi even though fueling and timing are fine.

Melting stuff is bad

I got a little concerned when i heard a whisper that one of the engines I had built had failed drasticaly, as i was told on the grape vine Devastated was I

The story goes, on the way back from IMM in Denmark, the engine spat its coolant out the exhaust in 500 yards, firing on only two cylinders and thoroughly cooked the engine.

The truth of it was just a head gasket failure brought on by detonation. And this is where i am let off the hook My engine build was fine. Filling up on the continent with 92 octane unleaded, cuased the plug to overheat, melt, promote detonation and take the gasket. Oopsie, this happened in germany and it took another two days to get the car and driver home

Bud, use tesco 99 and maybe some booster in there as well, just dont melt anything