Engine numbers

[tm 50]

Can any one shed some light i have two grey motors with engine numbers but no prefix letter, ie F or J etc , so how do i determine what model that they are actually out of

[tm 50]

So the two motors are fj then, i measured the bore with the vernier on one motor and it came in at 3.05 inches

[tm 50]

Yep thats whats on top of pistons STD, and it measures up close enuff, just the numbers throw me unless they were restamped at some stage

[tm 50]

yep good for an FJ std bore no good for me i was hopng to cheat and get one rebuilt and swap motors over later keeping mine mobile in the interim

[FB MAD]

To identify an FX block from an FJ block the FX numbers started at 1001 and went to 121694. An engine number between these two identifies as an FX block.The are probably ?? date codes on the block ?? that might also help identify but I'm not up to speed on any date coding ( if any ).

I have an FX block ( 132 ) cube here with STD 138 pistons so the 132 blocks should at least rebore,if needed, to at least 138 cubes ( maybe more ?? ).

Hope that helps...............

[FB MAD]

I think a 138 standard is roughly a 132 60 thou over. As these were cheap pistons in the day a lot of reconditioners liked to do this on the first go. When I recoed my FJ motor in 1996, they wanted to go straight to 138 standard (first rebuilt 93K miles)
I hunted around and luckily found a set of 20 thou over 132's.
Hard to find now
Tim

Yep, the FX block I have has standard GMH 138 pistons Tim and from memory when I did the measurements they equated to the equivalent of 60 thou oversize 132 pistons.

[FB MAD]

So the two motors are fj then, i measured the bore with the vernier on one motor and it came in at 3.05 inches

Standard bore 132's are 3.000 inch.

If you measured your bore and it came out at 3.050 inches then your 132 is oversize already.

Standard 138's are 3.062 inches so your 132 at 3.050 would probably equate to around a 40 thou oversize 132 as is ( with sitting down and working it out exactly ),could be 60 thou oversize maybe ?? depending on how accurate your measuring was.

"Technically" your 3.050 measurement is 50 thou over but highly unlikely as most aftermarket piston oversizes were .020,.030,.040 and .060 thou oversize.

Factory GMH oversizes were .003,.010,020,.030,.040.

[tm 50]

thanks fellas i new between you two i would get to the bottom of it "Legends' i have a 138 j series might strip it down and possibly use that

[space ace]

My fe engine number begins with "p"
Pete

[Trev]

I think the "P" is a restamped engine buy the police? Just what I've heard .

[space ace]

[FB MAD]

I think the "P" is a restamped engine buy the police? Just what I've heard .

Yep,


"p" Prefix usually denotes a replacement engine number given to a replacement block and stamped in manually.

The numbers in those days were given out by the Police in the various states and were used for unstamped new engine blocks.

I used to think it was given out as a replacement number for a previously stolen and recovered engine but after a post on the FE/FC forum a few years back on the same topic and input from Ken McClean ( and FE/FC guru ) it appears that wasn't correct.