ACL forged pistons

[love ke70]

my workshop was saying the rings are cast iron, apparently they are still the ducks nuts in rings....
and apparently cro-mo is something to stay clear of..

[rms]

as far as im aware acl make all of their own products

ACL forged pistons for the 1uz are manufactured by Ross for ACL.
They have a different skirt profile to the genuine Ross piston.

Info is direct from ACL Technical.

[fixeruperer]

cast rings are weak and they break but they wear in quicker good for a non stressed application, crome rings are alot stronger and harder and take longer to bed in you can bend crome rings with your hand but if you did the same to a cast ring it will just snap with the slightest bend.

[love ke70]

cro-mo rings apparently blow to shit at the first sign of detonation apparently. dont know if cro-mo is what is referred to when people say chrome rings..?

[fixeruperer]

that would be cast rings (that blow to shit).

[The Real Roadrunner]

cro-mo rings do fracture if detonted but chrome ones are different. cast rings are fairly strong and have their uses but also have weaknesses. and in the right application they dont blow to shit.

cheers
linden

[twentyEight]

Rohan,

I have a set of ACL Race Series forgies for a 3S-GTE if you want a first hand inspection...

[love ke70]

would you mind elaborating? i tried doing some searching but couldnt turn up much, the 1g im building is going to be making decent power, mainly a weekend warrior type vehicle. what would be the pick?

[The Real Roadrunner]

honestly, i dont build motors (but know enough about them to do so) therefore my personal preference doesnt matter, but generally it depends on the engines exact use and what type of engine.

different engine builders will use different types also depending on what they like.

personally if i were building a 1g there would only be one person id ask (6BOOST) because he knows exactly what works for a 1g.

if it were a different engine then i would ask someone with experience on that particular engine.

as far as cro-moly rings go, no i wouldn't put them in any turbo engine

apparently the top ring on most acl race pistons is chrome and the second ring cast, from the builders ive spoken to they are a good thing and most prefer them over arias.

cheers
linden

[jeffro ra28]

Chrome rings are a no no in harsh conditions which may introduce lots of foreign particles into the intake air. e.g. dusty applications. Also, a no no in nickle plated bores. If i remember correctly.

When it comes down to it. I think it is a pretty equal playing field with most run of the mill piston brands, until it comes to the likes of Mahle, HKS, Tomei and Cosworth, having seen machined and had a direct relation with the engines they were used in.

My opinion is that ARIAS, ACL, ROSS, JE, SRP, CP are all of rather eqaul qaulities. However if you ever get the chance to see or use somthing like Mahle, HKS, TOMEI or COSWORTH im sure you would agree they are probably the leading brands, their price tag will also relfect this.

It aint just the appearance, material qaulity or size tolerances but things such as the HKS "ultra flat" ring grooves and hard anondised ring lands and cooling channels is what i beleive to be the next level in piston technology. Physical appearance also has a slight difference between them.

P.S. If you manage to break them, it usually isnt the pistons fault. Most of the time, if the tune is right, the first failure you will see is minimal cracknig on the inside of the pistons where the crown moulds to the gudgeon boss.

[9000rpm]

I have spoken to ACL technical about this when trying to get RB20DET pistons.

They told me their piston blanks are Mahle because ACL owns Mahle.

http://www.mahlemotorsports.com/C125...MPHFX458STULEN

They only machine up the blanks here in Australia. I have also seen Mahle boxes there at the ACL plant too from memory.

Here it says Mahle are different part number:
http://www.aclperformance.com.au/ev_subaru_EJ20T.htm

[amichie]

I recently bought a set of oversize ACL pistons for my 7mge and it clearly said on the box that ACL and Mahle were the same.

The ACL web site is also very informative and includes a really good FAQ section.

I wanted rings and pistons that would withstand my LPG set up with out any dramas and the FAQ section covered all relevant topics.

[twentyEight]

On the ACL Race Series Forged Pistons for a 3S-GTE, the top ring is Nitrided Steel...

[merc-blue]

Rohan,

I have a set of ACL Race Series forgies for a 3S-GTE if you want a first hand inspection...

Mate might take you up on that offer,
let me know when its good to come have a look

[EVO 747]

too dig up an old thread for some clarity.
Ordered a set of 4AGE ACL race series forged pistons from veale's at a decent 750 price tag and picked up a nice new shiny set off ROSS forged pistons today! seems the acl forgies are made by ROSS and they are not even bothering to re-package them now.