AA Performance P&C kits, Anyone have experience? Options

[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]

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]

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

(IMG:style_emoticons/default/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! (IMG:style_emoticons/default/biggrin.gif) That's 914!

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]

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]

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]

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!!!!!

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.