Help - Search - Members - Calendar
Full Version: AA Performance P&C kits
914World.com > The 914 Forums > 914World Garage
Kansas 914
I have a 2.0L motor sitting around that was water siexed (rusted) ao this weekend I pulled it apart.

Needs new pistons and cylinders so I was looking at this big bore (no machining needed) kit.

Anyone have experience with this particular kit?

http://aapistons.com/index.php?main_page=p...;products_id=58
scotty b
Grab your dice, and roll them. Do a search here, they have been discussed many times
904svo
Buy a big bore kit from Jake!!!!
IronHillRestorations
Cheap chinese junk will be cheap chinese junk. You might get lucky though and get a few thousand miles out of a set before it costs you some real money.
tomeric914
About 10 years ago AA's cylinders used to be nice and fit perfect. They even had a black coating on the fins which has never burnt off.

The last set of cylinders I purchased from them were junk.
Kansas 914
I just don't have $5000 to drop on parts for a motor I may never use.

The spare is a GC case (#0000022) and the kids in the neighborhood want to build it and make it run.

Just a learning project as much as anything else.
hot_shoe914
QUOTE(Kansas 914 @ Sep 12 2010, 07:41 PM) *

I just don't have $5000 to drop on parts for a motor I may never use.

The spare is a GC case (#0000022) and the kids in the neighborhood want to build it and make it run.

Just a learning project as much as anything else.

I have a set of the 96mm that I bought about 2 1/2 years ago. I still haven't used them. Let me know if ya decide to go that route and I might just sell mine. You could pick them up at MUSR11.
sean_v8_914
I have an AX 2056 D-jet motor that has run 96mm AAs since 2005. the engine has never been driven gently . it has well over 100 events on it before we put it in another car. after 2nd season, I replaced the rings with grant rings. didnt need them but I pulled it apart to see how much of all this was internet blah blah vs reality. the motor has over 20000 roard miles and now is back in teh 10jreen as our back up. the 10jreen's 2.4 also has AA 103s. they too are in great shape after 3 seasons of 2 guys flogging it.
I use AA 96mm frequently but I use better rings like grant or hastings
if your budget is strong and you only want the best ingredients then bore out OEM 94 cylinders and use KB or JE pistons...just buy Jakes kit
sean_v8_914
if someone has real evidence or first hand experience with poor quality, please share the data so we can learn about the failures
rick 918-S
QUOTE(sean_v8_914 @ Sep 13 2010, 08:10 AM) *

if someone has real evidence or first hand experience with poor quality, please share the data so we can learn about the failures



agree.gif Real data vs comments on junk.
sean_v8_914
the link you sent me was for the biral cylinders. I can not recommend those since I have no test data to support any claims good or bad. Biral is a cast iron sleeve with aluminum fins cast over it. in theory it should be better heat dissipation.
the kit I have used is cheaper cast iron cylinders with cast hypereutectic pistons. AA has them made in china and does the machining here in costa mesa CA. under $300 for pistons, cylinders and rings. for heavy duty applications like AX, I recommend upgrading the rings and a flatter hone angle
rhcb914
So, being the cheap bastard I am I bought a set of AA off of ebay.

Overall I am extremely satisfied with these parts. I built the engine over the winter and have about 3200 miles on it so far this summer. Broke the engine in hard, bringing the car imediately to the redline several times shrotly after the 20 minute cam break in period. Oil consumption has been almost nothing. I know some folks have had a problem with the rings seating but for me it wasn't an issue.

Now the things that you need to look out for.

1) Rings had .002 of gap when I measured. Not really a big deal because we should be checking and setting anyway.

2) Says pistons are balanced within 1 gram, I found this was not the case, more like 4 grams. Was able to match the heaviest rod with the lightest piston and only remove a small amout of material to get where I wanted it.

3) Height of cylinder from shoulder to top mating surface varies a bit. There was about .004 variation. I was able to swap each cylinder around and find the best combo. So far no leakage from either bank of cylinders.

I would suspect you would find similar issues with any set you bought but for the price I would highly recommend based on my experience.

-Rob



rick 918-S
Thanks Rob, Real world info. What did you end up setting your ring end gap to.

Rich Towle told me he ball parked his pistons on his scale then used the high end scale down at the post office to fine tune his pistons. That's cool! biggrin.gif That's 914!


QUOTE(rhcb914 @ Sep 13 2010, 08:59 AM) *

So, being the cheap bastard I am I bought a set of AA off of ebay.

Overall I am extremely satisfied with these parts. I built the engine over the winter and have about 3200 miles on it so far this summer. Broke the engine in hard, bringing the car imediately to the redline several times shrotly after the 20 minute cam break in period. Oil consumption has been almost nothing. I know some folks have had a problem with the rings seating but for me it wasn't an issue.

Now the things that you need to look out for.

1) Rings had .002 of gap when I measured. Not really a big deal because we should be checking and setting anyway.

2) Says pistons are balanced within 1 gram, I found this was not the case, more like 4 grams. Was able to match the heaviest rod with the lightest piston and only remove a small amout of material to get where I wanted it.

3) Height of cylinder from shoulder to top mating surface varies a bit. There was about .004 variation. I was able to swap each cylinder around and find the best combo. So far no leakage from either bank of cylinders.

I would suspect you would find similar issues with any set you bought but for the price I would highly recommend based on my experience.

-Rob

rhcb914
I set the compression ring @ .025. The second ring at .020 and I don't remember what I used for the oil rings. I think somewhere around .015. I have it written down somewhere in my notes. I'll see if I can dig up the specs tonight.

Rich is a character! Very creative. I actually used a kitchen meat scale to ball park everything. Then borrowed my dad's balance scale from his days as a chemist to dial in the tollerance to about 1/2 gram. That was time consuming! But pays you back every time you spool up the engine to 6K!



rhcb914
One other thing I forgot to mention. Deck height was a bit high on these. With no base gaske or head gasket I got .068 of deck height. That was more than what I wanted but with the 50 CC heads and my 1911 cc displacement I ended with 8.6 compression ratio which is right where I wanted.

If I was building it again I would have had the base trimmed and targeted closer to a .040 deck height and had the heads worked to have a slightly larger chamber and kept the compression ratio about the same. But all that costs $$ and I have already said I'm a cheap bastard!

The engine was not hard to tune but I can smell a very slightly rich mixture at idle. If I jet down the idles I get occasional lean pops just before transitioning to the mains. Stick with .050's and it transitions fine. Dial in the idle screws so I don't smell the exhaust and I get light popping on deceleration. So I just deal with a slightly rich mixture at idle possibly due to incomplete combustion from the larger deck height. Overall, plugs look great and overall the engine runs excellent!
Kansas 914
QUOTE(rhcb914 @ Sep 13 2010, 09:51 AM) *

I set the compression ring @ .025. The second ring at .020 and I don't remember what I used for the oil rings. I think somewhere around .015. I have it written down somewhere in my notes. I'll see if I can dig up the specs tonight.

Rich is a character! Very creative. I actually used a kitchen meat scale to ball park everything. Then borrowed my dad's balance scale from his days as a chemist to dial in the tollerance to about 1/2 gram. That was time consuming! But pays you back every time you spool up the engine to 6K!

Hi Rob,

This is great data - thanks for the detail.
sean_v8_914
I will discuss these issues with Johnathan at AA
Kansas 914
QUOTE(rhcb914 @ Sep 13 2010, 10:23 AM) *

The engine was not hard to tune but I can smell a very slightly rich mixture at idle. If I jet down the idles I get occasional lean pops just before transitioning to the mains. Stick with .050's and it transitions fine. Dial in the idle screws so I don't smell the exhaust and I get light popping on deceleration. So I just deal with a slightly rich mixture at idle possibly due to incomplete combustion from the larger deck height. Overall, plugs look great and overall the engine runs excellent!

Hi Rob,

What cam are you using on your engine?

Also - What carbs are you using?
rick 918-S
QUOTE(sean_v8_914 @ Sep 13 2010, 11:25 AM) *

I will discuss these issues with Johnathan at AA


Nice to have that connection! I'm looking forward to using the set I bought for Sandy's cars as soon as I get the heads back from the chevy machine shop. (= low cost head work)
dr914@autoatlanta.com
The AA piston and cylinder kits as scotty says are a crap shoot but so cheap that they can be used and taken the extra time to match up and measure. We use them here for cheap engine rebuilds and have not had a problem after carefully fitting weighing and mic ing them. NPR were the best made in Japan but long discontinued. As an amusing anecdote, after the war my dad called the stuff from Japan cheap jap crap!!! Then japan got better and better, until he actually PREFERRED products from Japan (except cars!!!!!)
Eventually the Chinese will be there.
Please note that the AA stuff is not ours!!!!!

QUOTE(9146986 @ Sep 12 2010, 09:57 AM) *

Cheap chinese junk will be cheap chinese junk. You might get lucky though and get a few thousand miles out of a set before it costs you some real money.

sean_v8_914
Nippon Piston Ring Co is still in business. they are considered high quality in some JDM circles...but they dont make low volume Porsche stuff...Nissan, Toyota...
96mm NPR pistons are built like tank pistons weighing in at a whopping 250+ grams over stock and even more over teh AA product.
I get the impresion that AA wants to get better but they get little direct feedback.
Rick: could you measure your cylinder height for us? I have run into the low compression issue due to too much deck height. this can be cured by AA in costa mesa when they machine down the castings.

***yes, I agree with comments above. measure everything...liike you should anyway
rick 918-S
QUOTE(sean_v8_914 @ Sep 13 2010, 08:08 PM) *

Nippon Piston Ring Co is still in business. they are considered high quality in some JDM circles...but they dont make low volume Porsche stuff...Nissan, Toyota...
96mm NPR pistons are built like tank pistons weighing in at a whopping 250+ grams over stock and even more over teh AA product.
I get the impresion that AA wants to get better but they get little direct feedback.
Rick: could you measure your cylinder height for us? I have run into the low compression issue due to too much deck height. this can be cured by AA in costa mesa when they machine down the castings.

***yes, I agree with comments above. measure everything...liike you should anyway



Sure, I already plan to make a deck height checker and have my heads CC'd.
Lennies914
Is deck hieght the distance between the top of the piston and the top of the cylinder at TDC?
Jake Raby
I've had a couple people ask why I haven't responded to this post, so I figured I would.

The AA pistons haven't met our expectations for about 3 years now, I pulled all of them off the shelf except the 1.7 and 1.8 sets because nothing else is available for those engines.

The pistons had lots of issues and the ring pack wasn't impressive for high mileage use. I found variances in piston weights that were greater than the amount of material that could be removed safely. Deck heights were everywhere. Piston/cylinder clearance wasn't adequate and etc. I DID give this feedback to AA and their response was "many engine builder use our part without problem" (I talked to Thomas, the Owner and thats exactly what he said!)

Since then the cylinders themselves have been recast and are nice. We couple these cylinders with the KB pistons and Hastings rings after going through lots of steps to ensure they are compliant, have proper ring gaps and have proper skirt clearance.

The VERY FIRST set of the KB pistons I ever used were applied to my 912E engine. See this page on my site for a complete tear down of this engine after 160,000 miles of hard service with almost no maintenance and extended oil drain intervals
http://www.aircooledtechnology.com/index.p...&Itemid=112

Now.. remember that these were the prototypes of this 2.0 KB piston, being the first set that was ever made and usually the first set isn't the best set no matter what we are working with.

Here are the KB pistons from this engine after those 160K miles.
IPB Image

When measured the rings gaps had only opened up .003, skirt clearance had worn less than a measurable amount and the pistons were simply cleaned up via our corn cob blasting technique, re-ringed with a new set of Hastings rings and resused. We honed the cylinders .0003 to clean them up (they were original 039 cylinders that now have over 260K miles on them) they were bored to 96mm when I built this engine the first time in 2002.

Here the pistons and cylinders are prior to reassembly with the new Hastings rings fitted.
IPB Image

Now the application of some "Snake Oil" engine assembly lubricant
IPB Image

Nice tight deck of .036 was attained on all but one cylinder, which was .035, achieving .001 variance between 4 cylinders is very hard to attain! Try that with AA pistons! Len decked my case perfectly which helped in the ability to get these deck height results, my registers were sagging very badly, like most. The engine is set up at 9.83:1, as I am looking to capitalize on the 37 MPG average this engine gave previously. I'd like to attain over 40, which I have done in the past with this engine in the previous state at peak.

And here it is completed and ready to test the prototype throttle body on the engine dyno, before going back into my 912E for another 150K+ miles of service!
IPB Image

Once I complete the engine dyno evaluations, install the engine into the car and get chassis dyno results I plan to make an extensive thread describing what needs to be done to "rebuild" a RAT engine after high mileage.. I'll share all the details of this engine there.

The bottom line is the AA pistons provide service for entry level engines and those that don't have high expectations for building high mileage, or super well blueprinted engines. For their cost they are a viable alternative for low performance applications. As with any Chinese made component you have to understand that the attention to detail isn't their biggest attribute and that should you have issues with them gaining technical support could be a challenge. If I had to choose one primary grip about these pistons it would be the ring packs that they use out of the box.

Don't take this post as an advertisement, because we are not the only people that sell the KB pistons.. We also don't have the cheapest price on them, because of what we do to them thats "extra" that may not be necessary.

We have used KB pistons in applications that far exceeded what the pistons were designed for and were advertised to do. This includes using a set in a Road Race engine turning over 8,000 RPM for a full season! To date I have NEVER had a KB piston fail that wasn't the fault of some other primary failure, like heat or oil starvation. I can't even say that for the JE pistons, because I have had them rip pin bosses out for no reason on the street and track!

KB pistons are very tough, resilient to wear, don't rattle at start up and generally consume around 1 qt of oil in 1500 miles, which is normal.. They are very hard to beat, 90% of what I build run them because they just plain work.

Does anyone have any pics of AA pistons with extreme high miles on them??
sean_v8_914
well said Jake, thanks.
there are levels that people are willing to pay for or not. no single mod is going to make power or reliability. it is the sum of the details that make an engine great vs OK. I speculate that most guys are OK with OK.
engine builders do things(details) automatically, perhaps subconciously, that the home builder will rarely think about. Hell, most guys dont even remove those AAs from the cylinders to install them.
rhcb914
QUOTE(sean_v8_914 @ Sep 14 2010, 01:53 PM) *

Hell, most guys dont even remove those AAs from the cylinders to install them.



Well that would explain why there is a high "failure" rate. How would you do the following:

1) CLEAN THEM??
2) Set the ring gap
3) Check to make sure there are no defects
4) Mock assemble to check for things like deck height

amongst other things.

I am not a professional engine builder, but I just can't see how you would over look those things.

sean_v8_914
a guy on this site built a 96 x 80 and didnt even measure deck. it ran smooth but gutless. it had about 1/4" deck and head CCs...whats that?
realred914
what are the prices fgolks are seeing for teh varius pistons. i am looking at a big bore 2056 for my motor as i would like to keep the stock FI and much bigger than that wont work.

any ideas on prices and vendors of the varius pistons?
Jake Raby
You reap what you sow... Take your time, spend what's required and do it once.
It took me and my nephew who I am training about 100 hours to complete the work to my engine... That was time well spent because I won't have to touch it for the next 10 years.
People who lack attention to detail have no place inside an engine. If you are too lazy to clean parts also have no place inside an engine. Cleanliness is the #1 fundamental that must be applied in engine building. I spend more time cleaning than assembling.
realred914
just trying to get a fix on the prices,

what is the going rate for the 2056 cc pistons from:
AA?

KB?

others?
rick 918-S
Thanks for the response Jake. I agree with Sean that most guys are OK with OK. There are many levels of ability. I'm kind of a hack machanic myself. But I like to listen and I like to try. Maybe I can offer up a couple of measurements that will help to improve a product. Maybe I won't have the experience. But I'll share what I have good or bad.
Jake Raby
The real question is "whats OK?"

Everyone has a different definition and perception of "OK".

Engines are never perfect, because they are mechanical and nothing mechanical will ever be perfect..
Don M
never mind
sean_v8_914
this makes me think of new car warrantees. 10 yr 100000 miles...the avg owner resells in under 36 months so the 10/100000 never comes into play. how many years/miles do most 914 owners keep their car for? I guess thats the level of OK they need unless they are like us: detail devils that flog the piss out of our cars.
I have to build it tough cause I never pull punches so it better take it. I wonder how long my first 2056 djet will last? its back in teh race car since we broke the 2.4's crank.
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.