Technical Question Pinto Pistons?

[eaa53]

  I have acquired a 200 Pinto block (i.e. NOT a 205) as part of a job-lot-buy and having stripped it I find that it may be worth rebuilding.

I have fixed the core plug problem (55p) and the drilled hole in the casting! (strange!) and now I find that one of the pistons is 'actually' broke! Yes I know Pisston Broke old joke, but it is broke.

The engine has clearly had only little use since this rebuild so I am guessing the failure of the piston warranted the owner to abandon the block. Indications for this are:-
honing marks are clear on the bore and the bores are lined but clear of scores,
the open end ring gaps in the bore are in the low tolerance band,
there is no blow-back marks on the skirts of any of the pistons and
the crank journals and shells are pristine.
Add to this there is very little oil debris in the sump.
I judge one or two 'race days use' or 200-500 road miles.

The bore is over size by 1.5 (making the displacement 2056cc) and the pistons are level with the top of the block indicating to me, high compression.

The crown of the piston reads:-

------------------------------------
HRP
92.29sc (or it could be 92.295C)
SPO .025
1.5
------------------------------------

There could be an 'AE' casting mark inside the skirt by the way....

Based on initial research on Google, I think that is a Hoerbiger, 1.5mm oversized, class C dimension-match, piston.

Okay comments on that interpretation are welcome please.



The second point is where do I buy a new piston? I will have to get the set up balanced but if I can source a new piston I could have a very healthy block to use.

There is no information on the net of any value I can find; remarkably no one on eBay has any for sale!


Thanks guys

[dave_bence]

The piston could be made by AE (they're part of the Federal Mogul group now).

Try Phil Jones, he's an agent for AE pistons:

http://www.pjed.co.uk/engine_development_spares.htm

['The Gaffer']

Try Phil Jones,

http://www.pjed.co.uk/engine_development_spares.htm

Very helpful company, couldent agree more.

[eaa53]

Thanks for the pointer.

Phil identified the piston as an AE 18755-V1 +1.5.

The HRP was a red herring, I am making moves now to obtain a piston and have the lot rebalanced not really required for the intended duty but it was clearly balanced before and I may as well do it again while its in bits.

Using this web site 'Compression Ratio Calculator by Bowling and Grippo'  -   www.bgsoflex.com/auto.html
I have calculated that the compression ratio of this block with a standard head and a 30thou head gasket will be 10.7-1.

Will I need to use higher octane fuel to prevent pre det. with 32deg ignition timing or will standard fuel be okay?


Regards

['The Gaffer']

That's good news.

Is Phil doing the work for you?

If so, mention you got his details from the BKCC