Aluminium Sleeves
 

Hey guys, was wondering if anyone has experience with engines like the Max Powers and Hasi engines that have aluminium sleeves instead of brass? I’ve heard that the break in is a fair bit quicker but they also wear out a lot faster? Any merit to any of this?
cheers

That makes no sense. The piston isn't touching aluminum

The one and only aluminum sleeve engine I ever had was many years ago and it was a bit of a disaster. Fast as hell though. Didn't last long enough to wear out

Aluminium has a higher expansion rate than brass so the idea of a quicker break in is more by a higher expanded sleeve.

The wear has nothing to do with the aluminium sleeve because it is hard chromed so there should be hardly no wear on the sleeve unless the chrome is not that hard. Chrome plating aluminium is a bit difficult and so a different chrome could be used.
But because the sleeve expands more you can imagine that temperature changes can have an effect on the pinch zone. that can cause the wear.

But aluminium is a good heat conductor so you can run engines cooler or looking from the other side: leaner to run the same temps as with brass.

Much appreciated! That’s what I meant when I say wear out, I meant I heard they tend to lose their compression/pinch quicker than brass sleeves.

I’ve been running both the Max aluminium and Hasi aluminium for some time now.

Both engines break in easier.

Both run cooler (5-10deg).

Both so far have held up extremely well. Most of the damage with any engine is done during the break in stage, so that’s the big benefit I think with these new style engines.

The bad wrap aluminium engines get was from the Sirio days 15-20 years ago, they were fast but didn’t last. Technology has come a long way since then.

Yep. My experience was with the Star made RB. That thing was a missile (modded by me, it was impressive) but didn't last long enough to wear out. Suffered not one but TWO piston failures.

I had experience with the RB aluminum sleeve motor, and it was the fastest my car had ever gone down the straight, but it didn't last long, wore out faster than the brass sleeve motors. It was also very finicky to tunning.

The RB Xenon was a Sirio made engine. based on the SIRIO S21-CL7 R STI

I did not know that...

RB Xenon R was a fantastic engine!!