L2481f-30 Piston's

twstdv6

Member
The Box say's L2481F-30, but the piston say's L2481 with no F and they are 30 over. Is this wrong? should the piston say L2481F? or can I use them?
 
The F stands for forged. I will see if I can find the ones I have here and see if they're stamped with 30 or not. I'd take a set of calipers and measure them myself though.
 
The box say's L2481F for forged and the Piston's say L2481..Are these not forged piston's? I guess someone did a switcher-Roo on me, lol. I know they are turbo piston's, but since they are not forged I'm guessing, should I use them or look for some new one's? Are they worth the trouble sine they are not Forged or are they?
 
I just pulled my engine today awaiting the arrival of my Champions. I have the TRW forged (standard bore) pistons.

trwpiston.jpg
 
That's the newer ones Preston. I've got 2 sets of the older ones and don't think they're marked the same way. I'll try and find them tomorrow.
 
Pics

Here's some pics of what I have.
 

Attachments

  • IMG_20101030_183246.jpg
    IMG_20101030_183246.jpg
    26.6 KB · Views: 248
  • IMG_20101030_183302.jpg
    IMG_20101030_183302.jpg
    33.6 KB · Views: 243
  • IMG_20101030_183401.jpg
    IMG_20101030_183401.jpg
    31.1 KB · Views: 253
Looks like an .030 piston to me. It also looks like old stock. I'll need to pull the set I have here and compair them to yours.
 
That's what i wanted to know, Thanks!

the forged piston you have is several years old---------for at least the last 4 years they have had a coating on the shirts-------i really dont' think that it matters about the coating but what i do think matters is that the older ones like you have came with a heavier pin to make it near the weight of the stock piston probably to negate a new balance-----------rebalancing with the lighter pin (has a much larger hole) really makes a lot of sense in a performance engine---------i have used a lot of these pistons over the years and had good luck until one of the faster cars i built had an issue with the pins galling and grabbing------after doing some more looking i found a few other cases of this as well------after research I believe the root cause is because its original application ( V-8) was not for a turbo application--------its oil ring deposits the oil inside the piston like most older piston designs--------the buick turbo pistons and most new high performance pistions have oil drainback holes in the oil ring land that directs oil directly to the pins--------i built a fixture to drill these holes and i use them in all my 2481 builds and so far things seem to be working fine...................RC
 
I believe that there's a post on here about this Rich. If I remember right the holes for the pins are cut to tight and you can also have the pin hole honed to reduce the galling issue.
 
I believe that there's a post on here about this Rich. If I remember right the holes for the pins are cut to tight and you can also have the pin hole honed to reduce the galling issue.

to me the pins seem to have adequate clearance--------Gm had the same problem with the early turbo pistions--------thats why they added the oil drainback slots to the 86/87 pistons---------i think its really an oiling issue and loosening them up doesn't seem to me to be a good fix---------
 
Back
Top