Arias Forgies - Problems ??

[TokyoTaxi]

Hi all,

I've recently had my engine rebuilt using Arias forged pistons and am getting huge blow-by and a huge drop in compression pressure ( should be 120psi-140psi but I'm getting 75psi-85psi ) :cuss:

I'm told that the rings are not bedded in and I need to replace these rings and bead hone the bores to fix the problem. I'm also being told by another source that these rings are simply no good and I should get Tomei pistons and rings.

I would really like to hear from anyone who has actually used Arias forgies in their turbo nissan and what the results were like ( before I possibly go ahead and waste more money doing the rings and bore hone ).

Thanks.

[Amaru]

im using arias and have had no problems whatsoever. I think in the end it comes down to how competent the engine builder is.

[KamikazeR33]

agreed

[T0nyGTSt]

I'm also being told by another source that these rings are simply no good and I should get Tomei pistons and rings.

Sounds like bullshite. Why would one brand (and an expensive one at that) be so much better than a trusted one like Arias.

The original builder screwed the job more likely.

T.

[TokyoTaxi]

Thanks all.

Well from what I'm told, the people who built my engine are some of the best in the game so I'm now putting the problem down to the oil that was put in (as run-in oil ) by the guys who fitted the engine, or the way I ran it in ( if that's possible ).

I guess my next questions are...... How did you run in your engine ? What oil did you use to run it in ? and How many kms for ?

Thanks.

[T0nyGTSt]

I just used mineral oil and I hit it like you'd hit Paris Hilton.

2,000km run in.

T.

[SeriesIIGTST]

I've just rebuilt my engine with Arias and have to that I've had no problems what so ever. Engine runs better than ever. I ran it in for 1,000 kms with running in oil (very thin) then changed to like a half/half mineral/synthetic mix for another 500 then switched to my normal oil 10W-40/50 (can't recall).

To give you an idea of how much better mine is now, I can chirp third consistently with 255's on the back!

[Amaru]

Used run in oil in mine for 500km's, did a full flush and replaced with Mobil 1 5W-50 for 500kms, did flush again, Mobil 1 5w-50 for 2500kms, did flush, and now its got Mobil 1 5W-50 in it and it goes better than ever.

When running it in I was told to put the engine under load (going up steep hills in a high gear like 3rd/4th so the engine has to work to get up it), never kept a constant speed, never idled for too long and it all seems to have worked well.

[KamikazeR33]

yeah ur supposed to run full mineral oil for like 1000kms then run semi for another 1000kms then whateva u want

[Bl4cK32]

When running it in I was told to put the engine under load (going up steep hills in a high gear like 3rd/4th so the engine has to work to get up it), never kept a constant speed, never idled for too long and it all seems to have worked well.

Same advice i was given, and will stick by. Gotta give it sum stick to get those rings to expand, and bed in.

[SeriesIIGTST]

Yeah, I also never maintained one speed...ie driving down a 100km/h freeway i'd do 90, then 95, then 100, then 105 (no i wasn't speeding, it just appears that way), up to 110, back to 90, etc...

Never let it idle for too long, basically drove it without boost but did load it up in high gears but not all the time. Seems to have worked for me.

[T0nyGTSt]

If you intend to hit the car hard for the entirety of it's life, you have to hit from day 1.

So common wisdom is that you flog it hard.

T.

[Whoneedstherapy]

If you intend to hit the car hard for the entirety of it's life, you have to hit from day 1.

So common wisdom is that you flog it hard.

T.

could it be that the clearances set by the engine builder were a little on the large side? as in to allow massive boost etc?

[Chris32]

would it be worth putting in some cheap mineral oil and giving it heaps to try and get the rings to bed in??

FAT32, what oil did they use to run it in?

[Nizmo]

Used run in oil in mine for 500km's, did a full flush and replaced with Mobil 1 5W-50 for 500kms, did flush again, Mobil 1 5w-50 for 2500kms, did flush, and now its got Mobil 1 5W-50 in it and it goes better than ever.

When running it in I was told to put the engine under load (going up steep hills in a high gear like 3rd/4th so the engine has to work to get up it), never kept a constant speed, never idled for too long and it all seems to have worked well.

Recently ran in mine using Arias ....... ran it in very similar to Amaru .... no problems what so ever .... only thing is my car sounds liek a ute when i start it up now ..... im not sure if thats normal or not

[Gav]

I've heard quite a few Arias fitted RB engines and they generally sound less "rattley" than say an engine rebuilt with Wiseco slugs.

I've been told that this is because they have a lower co-efficient of thermal expansion compared to other forged pistons, and therefore the clearances can be less (ie more in line with OEM pistons).

Anyone know for sure?

[RNS11Z]

GAV: i dont know were you heard that from but i had wiseco's in my engine when i rebuilt it and it never rattled, nor did it rattle with the ariais in the previous engine. how ever i did get some blow by with the arias.

In regards to running in, I used motul oil and drove it slowly for the 1st 200kms then started canning it from then on. At jamboree last yr when i raced the engine was under 500kms old on the saturday.

Come 7 months/ 10 000kms later the car is still going and going strong.

i guess it just comes down to the way the engine is built

harun

[Clint32]

yeah the engine build is very important but the way you run the engine in will determine if you have a good engine or not, doesent matter if the engine is done perfect if you do it wrong it will burn oil.

im currently getting my engine built and getting a 550hp setup together, my biggest problem is running the engine in as i have a new computer and will not be able to run the stocker as i have a 32 and fitting a rb25engine, so i need to tune and run in together, not a good thing

[wrxhoon]

i used arias pistons when i rebuild my rb 26 , 87 mm , 4 thou clearance . as with all chrome rings you need a good hone . i used run in oil for 800 k then mineral oil for 4000 k then helix ultra . when running it in put it under load from the start but only for short periods like full throtle in higher gear for like 20-30 seconds then back off then on again . i have no problems with blowby whatsoever and 175 compression .

fat 32 , did they bore it out to suit the new pistons ? the clearances maybe to big or the ring gaps to big

[TokyoTaxi]

Thanks for all the info Guys & Girls.

Here's the low-down. ProFlow at Rossmore built the engine and they're renowned for building high quality and high power engines ( mostly big HP V8's for drags ) and I have very little doubt in the quality of their workmanship ( however, after sales service leaves a little to be desired ). The bores were machined to suit 40 thou oversized Arias slugs.

The guy that installed the engine ( not ProFlow ) put Synthetic 5w40 oil in as run in oil which I didn't know about ( and don't really think is correct ). He believes that itwill make no difference at all to the run-in.

The car: From a cold start up to operating temp, the engine is as quiet as a mouse and driving the car is reasonable until you hit the loud pedal and get up on 18-20psi boost and then the oil catch can goes from empty to full in no time flat ! I ran the engine in for about 400kms before changing oil and filter but the car just seems to be going down in power every time I drive it.

From all that I've heard now ( forums, workshops, and owners ), it would appear that Arias pistons and rings are great so long as boost is kept below 18psi ( due to ring design ) and if you want to run bigger boost than that you're best to get Tomei or Jun pistons. This is only a conclusion that I've made from talking to around 40 or so people re this subject.

Since I'm essentially broke at the moment I'm thinking of doing what Chris32 ( and others )suggested and chuck some mineral based run-in oil in, turn down the boost to about 14psi max and thrash the nuts out of it to see if the ring might bed in. If this doesn't work I'll just park the car and start stripping it