Author Topic: L-2248 Std forged pistons  (Read 3068 times)

opelitis1

  • Member
  • ***
  • Posts: 261
    • View Profile
L-2248 Std forged pistons
« on: October 22, 2008, 02:17:39 PM »
Any idea of what these pistons are for and a bit about them???  Checked a '76 TRW catalogue and came up with zero info..  Googled L2248 and also nada.. 
Thanks!! Ted

Tinkerr

  • Member
  • ***
  • Posts: 127
    • View Profile
Re: L-2248 Std forged pistons
« Reply #1 on: October 22, 2008, 02:24:14 PM »
that looks like TRW # similiar to the 11-1 .030 over 350 pistons I used a number of years ago. I think that # was L-2242.

dutch

  • Member
  • ***
  • Posts: 306
  • Documented Canadian 1968 Z/28
    • View Profile
Re: L-2248 Std forged pistons
« Reply #2 on: October 22, 2008, 03:46:29 PM »
   Im not sure if you are searching for 302 parts as per your other posting regarding the crank ID'ing - but I do know that the old TRW part number for their forged 302 piston years back was 2210-AF. I am not completely sure about that AF suffix I added there - but the #2210 is good for the .030" version and is what I have presently in my 302 short block at home.

opelitis1

  • Member
  • ***
  • Posts: 261
    • View Profile
Re: L-2248 Std forged pistons
« Reply #3 on: October 22, 2008, 05:52:43 PM »
These pistons L2248 came from block casting number 3789935 dated  2 C9. Believe the block is a 283ci  maybe 1962 month of March / 9th day...  Just can't pick up the L2248 numbers from my catalogues... They are forged units with about a 1/2" dome..
Also tried Google and still nothing a showin' up...  Rods have been balanced by ball milling into the big ends of the caps...  Was this how it was balanced "back in the day" and is it safe to run 'em like this???  Thanks  Dutch and Tinkerr for getting back!!   Ted

Classic Gary

  • Member
  • ***
  • Posts: 64
    • View Profile
Re: L-2248 Std forged pistons
« Reply #4 on: October 23, 2008, 04:41:34 AM »
These pistons L2248 came from block casting number 3789935 dated  2 C9. Believe the block is a 283ci  maybe 1962 month of March / 9th day...  Just can't pick up the L2248 numbers from my catalogues... They are forged units with about a 1/2" dome..
Also tried Google and still nothing a showin' up...  Rods have been balanced by ball milling into the big ends of the caps...  Was this how it was balanced "back in the day" and is it safe to run 'em like this???  Thanks  Dutch and Tinkerr for getting back!!   Ted


L2248 and L2249 left and right or (vise versa) (pin offset), for a 315HP 283 @ 11.5 to 1 compression of the early 60's. and I need a .060 over one to put a motor back together !! If they are the 283 rods DO NOT USE THEM. If they are small journal 327 rods then it's OK.
opinions are like wallets, some just aren't worth stealin'.

opelitis1

  • Member
  • ***
  • Posts: 261
    • View Profile
Re: L-2248 Std forged pistons
« Reply #5 on: October 27, 2008, 10:34:16 AM »
I have one of the L2248 Std pistons/rods  in front of me... On the piston face is there a (right or left) coded???  How can I spot the difference between a 283 small journal rod vs. a 327 small jrnl unit???  Why is the 327 SJ rod better than the 283 SJ rod???  Was that the way they balanced rods back in the day by ball-milling into the big end of the caps??? Some of the caps have 4 - 6 holes milled outta them - was it safe to do this and why???    Thanks!!!   Ted

Classic Gary

  • Member
  • ***
  • Posts: 64
    • View Profile
Re: L-2248 Std forged pistons
« Reply #6 on: October 27, 2008, 03:38:30 PM »
lots of questions,
1. no there are not stamped as to left or right, the number is left or right. I can goto the shop later and take pics of my pistons and try to figure left or right. You CAN see the pin offset, or you can measure from the skirt to the centerline of the pin.
2. 327 rod is STRONGER, i can take a pic of the 327 rod I've got.
3. ball milling is just a preferance as to the machine the engine builder/balancer has. I would not ball mill, it can go too deep into the cap and make it weak.

JohnZ

  • CRG Member
  • *****
  • Posts: 4250
    • View Profile
Re: L-2248 Std forged pistons
« Reply #7 on: October 27, 2008, 03:40:07 PM »
The photo below is kinda crude, but it shows the visual difference between 283/early 327 rods and the later 327 rods; on the 283/early 327 rods, the machined surface is the same width all the way around the big end. On the late '66-up 327 rods, more meat was added adjacent to the rod bolt heads, which shows as a "bump" on the machined surface adjacent to the rod bolt heads. You do NOT want to use the 283/early 327 rods in a performance application - they're inherently weak.
'69 Z/28
Fathom Green
CRG

opelitis1

  • Member
  • ***
  • Posts: 261
    • View Profile
Re: L-2248 Std forged pistons
« Reply #8 on: October 27, 2008, 07:12:04 PM »
Great info!!!  Thanks!!!  Ted