another engine identification

[minijojo]

i have a engine standing in my garage.Got a few problems with identification
The block is labeled 12A497, the engine numberplate shows 8G162 ES(B or 1509 with AD stamped in the second row in the space. The bore is 64,5mm and the stroke is 84mm. Seems for me to be a 1098er Block. I found by searching the forum that engine numbers starting with 8G are gold sealed blocks, that agrees with the color of the block

Motor12.jpg (2.25 MiB) Viewed 4187 times

Motor01.jpg (3.81 MiB) Viewed 4187 times

the Head is MOWOG 2A629 with inlet valve head size 29,5mm and outlet valve head size 26,0mm, for 2A629 i found, head for a 948 engine.

Motor09.jpg (3.08 MiB) Viewed 4187 times

is there somewhere a listing with all a-series heads, valve sizes and combustion chamber size?

final question, is it a good idea to use this combination for a rebuild?

[geoberni]

You've typo'd in your description, that Block is 12A497

if you refer back to my recent discoveries, you'll see that means it's a 1098 as you thought. Perhaps that's where you've already looked.

viewtopic.php?f=4&t=67378&hilit=block&start=20#p642731

As to the head, yes, it would appear to be a 948 head for a Minor/A35
https://www.calverst.com/technical-info ... ng-number/

As I'm useless with engine tuning details, I'm sure somebody who does know their stuff will be along to comment shortly.

[minijojo]

thanks for your note, corrected it in the original posting
and yes, this was the posting i found with the note to the gold sealed engine

by the way, nice car, same age as me.....

[philthehill]

The block is from a 1098cc 'A' Series engine.

The 2A629 head is from a 948cc 'A' Series engine.

The head should be a least casting number 12G202. The smaller valves and ports of the 2A629 head will restrict the engine breathing and ultimately effect the power output.

Here is a list of 'A' Series cylinder head used on the most popular 'A' Series engines:-

cyl head details.jpg (870.85 KiB) Viewed 4159 times

[minijojo]

many thanks Phil, that´s what i was looking for

would a 12G295 be an option? It´s because i got one stored. It has a bit bigger inlet valve and 2.2 cc more chamber volume.

We discussed about this head to be mounted to a 948 with shimming.
viewtopic.php?f=4&t=63877

[philthehill]

The 12G295 head skimmed by 0.060" is an excellent option. The standard head is 2.75" deep from top to bottom machined faces.

[minijojo]

thanks again Phil
now my opions are, rebuild and skimm the 12G295 or get a 12G202 for rebuild

by the way, does someone got a 12G202 head in usable (for rebuild) condition and is willing to post it to Germany?
pm me for offers plaese

[philthehill]

I would suggest that you skim the 12G295 head. The only reason to skim the head is that the 12G295 head combustion chambers have a larger volume than the 12G202 (see chart I previously posted) and so to bring the combustion chamber volume (and compression ratio) back to the same as the 12G202 you need to skim by 0,060".

I would also suggest that it would be cheaper to skim the 12G295 head than incur the cost of purchasing a 12G202 head and the courier delivery charge.

The 12G295 head is better in every way compared to the 12G202.

[minijojo]

thanks again Phil, will follow your advice

[minijojo]

last question to complete this
what would be the best carburettor for this setup?

My available options
single HS2, standard inlet- outlet manifold available
twin HS2, no outlet manifold available
single HS4, standard inlet- outlet manifold available

[philthehill]

HS4 on standard late inlet/exhaust manifold.
The HS4 is 1.5" so the inlet tract will need to be blended in.

I would recommend that you obtain Clive Trickey's books on Tuning the Mini and More Mini Tuning. All you need to know about tuning the 'A' Series engine to the level you require is set out in the books.

https://www.ebay.co.uk/itm/VINTAGE-AUTO ... Swz4ZdbiOd

https://www.ebay.co.uk/itm/MORE-MINI-TU ... Swvfpdgokn

[minijojo]

thanks again, will have a look for that book...