block casting on grey motors

ek61 · Post by **ek61** » Wed Jul 01, 2009 3:52 pm

looking at rebuilding a grey 4 the ek
can any one tell me why these 2 engines have different block castings?
the ribs that run down the side of the block
maybe first pic is 138 and second pic is 132?
i did write the engine numbers down but left them at the shed

cheers dave

mrs ratbox · Post by **mrs ratbox** » Wed Jul 01, 2009 10:21 pm

was talking to a fairly knowledgeable guy the other day was an actual holden mechanic and has run a very competitive front engine dragster (red motor) for a long time he reckons there is 3 size reds 132 138 and 143 was something he was surprised about

FB MAD · Post by **FB MAD** » Thu Jul 02, 2009 9:22 am

Just checked my GMH master parts catalogue which runs from '48 to HD.

No mention made of pistons in EJ being larger than standard 138.

However,

The oversize GMH pistons available went from .001 .002 .003 .020 .030 .040 thou.

I guess it wouldn't be much trouble for Holden to bore the 138 out to .040 thou oversize which ( without actually sitting down with the calculator and working it out ) would probably work out to around 143 cubes.

The .040 thou pistons ( if they are genuine GMH pistons ) would be stamped on the piston crown with part number 7406474.

I suppose its "possible" that at the near end of grey motor production that they may have looked at getting rid of surplus oversize pistons and fitted the .040 ones into the late run engines??

I suppose forum member Dr Terry might be able to answer that one

Interesting to see an optional GMH 4 ring piston for the grey available as well.

If you find a grey with these part numbers stamped into the piston crown you have a 4 ring piston set in it.

Standard Optional 4 ring type FB,EK,EJ Part Number M32518
.020 " " " " " " ' " " " M32520
.030 ' " " " " " " " " " M32521
.040 " " " " " " " " " " M32522

Also avaliable was a semi finished 4 ring piston " M32523

High Performance grey motor stuff here

ek61 · Post by **ek61** » Thu Jul 02, 2009 3:33 pm

engine in 1st pic engine number L558770 block cast 7408858
engine in 2nd pic engine number 247483 block cast 7400479

fb cruzn · Post by **fb cruzn** » Thu Jul 02, 2009 4:50 pm

think iv mentioned it on ere before but my grey has std in top of piston, but std grey (138) rings were way too small to fit over, the guy at the parts shop said they were 149?(i think, it was a long time ago) but he also said they were std in grey repco engines.
im asuming repco recond/modifyed these engines?
it was all a long time before i was born

ill get the engine number when i get a chance, it might shed some light?
now that i think of it, he did say dont wreck the pistons coz id never get another set!
so maby it wasnt 149

mrs ratbox · Post by **mrs ratbox** » Thu Jul 02, 2009 6:13 pm

i had one it was going in the chop top originally, wondered why it had split bores with standard on top of the pistons spose 161 pistons in a gray motor will do that

my mates dad older guy that grew up when hotty grays were the thing said it was something that was done but split bores were a consequence

feute · Post by **feute** » Thu Jul 02, 2009 6:38 pm

Heres the engine number dates

engine in 1st pic engine number L558770 block cast 7408858
FC Approx April 1959

engine in 2nd pic engine number 247483 block cast 7400479
FJ approx Nov 1955

ek61 · Post by **ek61** » Thu Jul 02, 2009 8:07 pm

nice work feute

so i guess it would be a 132 then?

will check the other grey engine i have and see what one is worthy of rebuilding

cheers again dave