912 Engine Project

[Jesse]

Looking good!!

Im about to order the same AA-set and would be keen on how well they match in weight?

I´ll put up a build thread as soon as I get down to business with my engine.

[James_Red69]

Yes no problem I am planning on posting a detailed review of this piston and cyl set to cover weights, cyl bore and piston diameters as well as dome volume etc.

Standby

[Jesse]

Really appreciate it!!

KR

[James_Red69]

OK here is a review of my Piston and Cylinder set.

My reasons for sharing all this info is that in searching for a replacement set that are within a reasonable budget I have come across many, many opinions, threads and anecdotal advice. You can go crazy with all the opinions, so I just took a leap of faith and thought I would share the results.

This is the set, it is AA 008 1186PB. I went with this set on the recommendation of Dave Dennett at DSD Motor Works - http://www.dsdmotorwerks.com who imported them for me (Dave also refurbed my heads).

http://aapistons.com/index.php?main_pag ... ucts_id=61



It is made in the same place that most stuff we consume is made;




Along the way I came across many opinions about P&C sets produced in China, most if not all were pretty derogatory based on claims of dimensions being out of spec, but no evidence being presented. I will let you make your own decisions after reading the information I have presented in this thread.

The design of the pistons is identical to the NPR Big Bore set (no longer made) that I have taken off the engine.





I have under taken the following;

Weighing



Measuring the bore and ovality of the cylinders;



Measuring the Dia of the Pistons;



And deck height with no shims fitted (to assist in calculating shims req. for any desired CR);




These are the results;




You can all make your own judgements.

Note that I am in no way affiliated to anything to do with AA products, China or any other aspect of the motor trade!

I hope that this information will be useful to some of you.

James

[James_Red69]

Now the satisfying part of bringing things back together.....












]

[James_Red69]

I have spent quite some time looking at my compression ratio. Any excuse for a spreadsheet! I decided to stick with just one 0.25mm shim.

[James_Red69]

Have been caught up in a seemingly endless list of 'well while Im at it' type jobs. The most significant of these has been to underseal the whole area above the transmission. I hate this kind of work for a number of reasons. Firstly there is the awkwardness of working at some obscure angle under the car whilst getting covered in cra*, secondly you never know what you will find whilst you are poking around, and lastly the mess of the application, even if you are totally prepared it seems to go everywhere.

Fortunately i found no nasty surprises, I spent longer masking and preparing than applying and made sure I was adequately protected - and the job is finished!


IMG_0323 by hangglider_james, on Flickr


IMG_0326 by hangglider_james, on Flickr

[James_Red69]

Ok things were going well. After waiting an age for oil cooler rubber mounting washers I finally got the thing installed. Then onto the generator stand....in my haste I dropped a washer down the hole, hearing it clatter down into the third piece my heart sank.

After cursing myself for 5 mins there was nothing for it, so stripping the various items I had already fitted it was off and on the bench with the offending washer retrieved.






So I am now in the market for a new third piece seal. If anyone has a spare lying around please PM me, I'm kind of keen to crack on!

James

[James_Red69]

Progress has been made. Thanks to all those who offered 3rd piece gaskets, and especially to Max at Revival for helping out with the seal installer.

Engine is now basically complete and I am finishing the following jobs;

Rear calipers - new seals and bust-boots
Half axles - new dust boots
Adjust hand brake
Replace accelerator pump diaphragm on one of the carbs
Reinstall.

All sounds simple - 'if it wasn't for those pesky kids.............'


IMG_0365 by hangglider_james, on Flickr


IMG_0370 by hangglider_james, on Flickr


IMG_0414 by hangglider_james, on Flickr


IMG_0430 by hangglider_james, on Flickr


IMG_0444 by hangglider_james, on Flickr


IMG_0445 by hangglider_james, on Flickr


IMG_0446 by hangglider_james, on Flickr

[James_Red69]

More progress, nearly back in the car. Tomorrow I have no work and no children so should be able to get things bolted back together.........


IMG_0490 by hangglider_james, on Flickr


IMG_0491 by hangglider_james, on Flickr


IMG_0494 by hangglider_james, on Flickr


IMG_0495 by hangglider_james, on Flickr


IMG_0496 by hangglider_james, on Flickr

[mooney3019]

Hi

Yes ive been reading yours and getting Tips, in regards to the torsion bar route, bit of a learning curve,

when taking apart remove all the bolts that hold the torsion arm to the swing arm so it releases the tension on the torsion arm, ensure you mark the inner arch as it is crucial to note where the swing arm sits unloaded, once you have this you can start taking apart, you have 2 allen bolts which adjust the camber/caster etc, mark with tippex on the heads so you know what position these will go back in at and should minimise adjustment.

when you get to taking the arm off the torsion bar, mine were stuck together and came out as one, so had to drill a hole in the end/dust cover and use a punch to separate them, this caused an issue for reassembly, beacause the inner splines are different to the outers, which is why it is crucial to mark the unloaded angle/position for re-assembly as its trial and error, I have used powerflex outer bushes on mine as the arms were rubbing on the top edge of the torsion cover, the inners are not av for SWB but LWB can be machined as they are larger, so for time being have used new normal rubber inners, the majority of the pivot and wear is always on the outer anyway.

Also where did you get you barrell shims from ??

[neilbardsley]

Just found this thread which unfortunately hasn't been updated for ages. Are you still on here? Is the car running well?