Kurt: I finally crawled under my car and pulled the rest of the #'s off of it. The car is a '68 RS/SS BB convertible. I will give you the whole run down again.
S/N 124768N408063
Trans: M21 #'s s/n 8N408063, P8C2 ( couldn't quite read this so don't know if it is exact)
Pt#3925660, #3857584 GM
Diff: BU 0325G1 E
Ring Gear: 3862525 11 41 3 68
Pinion: 3862513 11 41 GM 2 2 68
Carrier: 30140PN1 ( could be U1 )
These gears I believe are original.
The odometer currently reads 68397 miles and the tic toc tach is a 6000 red line. I know this car has been sitting alot since 1983, don't know prior to that. Do you think this car is a true L78 car?
As luck would have it I have located a 4 bolt block #'s are TO322MQ S/N 8N406921. The only issue is that one of the lifter bores is cracked. My local machine shop tells me this can be fixed simply by sleeving it. Any comments?
I could put some pictures on the system if I knew how.
Thanks

If that's a true M21, the only 2 engines available with convertible and M21 were the L34 and L78. But I can't think of any feature to distinguish which engine it would have been.
The 3.73 rear (March 25th) was a special order. The data I have shows the standard gear for a L34 was a 3.31, perf gear was 3.55. Standard gear for a L78 was 3.55, perf gear was 3.73. So it was either a perf gear L78 or a special gear L34. Not conclusive.

The trans code looks OK, but it is missing the last digit. March 2?, 68.


------------------
Kurt S.
CRG www.camaros.org (http://www.camaros.org)

Is there a code on the radiator? How many fuel lines from tank 1= L78? 6,000 rpm redline tach points toward L78.

------------------
'69 SS 396/375hp L78 M21 3.73 Fathom green/medium green interior

See a picture of my Camaro here:

http://temp.corvetteforum.net/c3/1970corvette//view.jpg

All 68's have one fuel line.
But the radiator tag is a good call.

Between the rear gear and the tach, I'm leaning towards an L78, but there's no definitive proof.

------------------
Kurt S.
CRG www.camaros.org (http://www.camaros.org)

Yes it does have the original fuel line (1)intact on the car. It has been blocked off and a new line has been tie strapped to it because of an electric fuel pump I'll check the rad out. Where is the tag info located?