Rare!!(?): Turner semi-finished pistons

[Smitty]

Well, I THINK they must be rare. One pair semi-finished Turner pistons for Merc B/D/F deflector. These will have a little more compression than stock Merc. Get them turned to your specs, inclucing your choice of ring groove(s). "Cam-grind" (using a file) to relieve the area around the wrist pins, and pin the rings. Molycoat the skirts so they last a long time.

$225 for the pair, plus $10 as your half of our contribution to the site.

[rich]

pistons

what would give these more compression then merc?

Rich 8-ce
DMH/DSH

[crankbearing]

20ci

Rich,

Those are .20 CI pistons, Get that thought out of your Head.

Smitty post some pics. What is the dome height currently? Alky or Gas.

Regards,

[rich]

Rich,

Those are .20 CI pistons, Get that thought out of your Head.

Smitty post some pics. What is the dome height currently? Alky or Gas.

Regards,

Gee Dave I was just curious
I have to do somthing while I'm waiting for class to start.

[crankbearing]

Yeah! Study.

Gee Dave I was just curious
I have to do somthing while I'm waiting for class to start.

Rich,

Yes! you can Study. So you can pass with an interprovincial ticket. Holy &()* I feel like a Big Brother. LOL An Inter-provincial brings more $$$$.

Sorry Smitty, was not trying to hi-jack the thread.

Regards,

[Smitty]

Sorry, I haven't got around to learning how to post pix. These pistons have the same skirt length and shape as Merc B/D/F pistons, and the same dome height.

However the shape of the dome appears similar to the early-version Merc pistons with the dimple and the center-drilled hole in the top. These look to me to have a little more material in the deflector than the newer versions of Merc pistons (there were three versions, total). My guess is that when Mercury got rid of the dimple, they took a corresponding amount of material out of the deflector so that compression would remain the same with either piston. The Turner pistons look to have the same amount of material in the deflector as the early Merc pistons but do not have the dimple, which is why I think they have slightly more compression than any of the Merc pistons. The differences are slight. If I could do a drawing, I could show you all of this better than with a photo, but . . . .

Hint: If you have a set of the old version Merc pistons, weld up the dimple and you'll have the same compression as the Turners. I have a pair for sale in my next ad.

[Smitty]

I'll take a closer look at the pistons and see if I can tell you any more when I get on tomorrow.

Dave, I haven't ever sold anything on ebay, and would like to try it, but am worried about a lot of probably-phony ebay and PayPal (which I have never used, either) spam messages I get in my e-mail Bulk slot. I don't open any of it, but if I start selling on ebay, I'll have to figure out what I can open and what I shouldn't. Any ideas?

[Smitty]

(the next day)

Looked at all the pistons, and I described them correctly. But an additional difference is in the leading edge of the deflector, where the intake charge enters from the port and is ramped up into the combustion chamber. In the first-generation Merc pistons (with dimple and center drilling) as well as the Turners, this ramp-up section does not wrap around the outer edge of the dome quite as far as in the second and third generation of Merc pistons. I don't know what practical effect this had, if any, but I do remember being told that Jeff Lowe used the old style pistons. Jeff was the fastest guy in Reg. 10 and argueably in the country, in the mid-'60s (Nat'l Champ, comp. record), and at that time the rest of us were using newer pistons. I'm not advancing this as a reason for Jeff's speed; for one thing, he was a terrific driver. But it is one of those "speed secrets" that used to obsess us slower guys.

In any case, Rich, it is obvious from visual inspection that the Turners have more compression, and that they were made from a mold taken of a first-generation Merc piston with the dimple filled in.

[rich]

pistons

thanks for the info.