full floating wristpins vs. pressed wristpins

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yes but you can get them cheaper than that. $3.80 a pop at rock: Sealed Power, not junk.
1968 DODGE DART 5.6L 340cid V8 Piston Pin Bushing | RockAuto

Also converting stock rods to floaters is probably more expensive than buying a set of 8 340 floater rods off this site. Seen them go for $40 a set.

Anyone got any advice using Teflon wrist pin buttons on floaters with no lock grooves? Soft enough not to damage the cylinders, tough enough to survive air cooled VW's...?
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They are fine for a race engine that you pull down frequently. I would not use them in a daily driver. Worked with a guy that raced a Porsche. He used them in the skirts. Good for one race.
 
Depends on your meaning of "converting". That is a replacement bushing for a rod which originally was prepped to have a bushing, Unless you intend on resizing the small end of the rod to accept a bushing. That's a lot of metal to take out! That wouldn't thrill me if I was asked to do this!

The rods are the same, whether bushed or pressed. At least with Mopar. That's all the factory did. They just honed the small end to accept a bushing. There's plenty of meat there to do it. People have been doing it for decades with no ill effects. It won't hurt a thing.
 
As far as drilling the top of the rod for pin oiling on floating pins I never have. Even on total race engines turning 7000 plus rpm. Kim

Yeah, I've seen opinions on that both ways. Even seen factory floated pins with no oiling holes at all. I can only imagine how much splash goes on "down there" even at idle.
 
Pressed do wear on top and bottom respectively while the floaters spin 360° and get worn evenly. That's about all I know. Lol.
 
Also converting stock rods to floaters is probably more expensive than buying a set of 8 340 floater rods off this site. Seen them go for $40 a set.


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I agree!
I don't think I'll be running out and snapping up more equipment that's going to sit in a corner, for the few applications that it would be used for that my power stroker pin hone can do, applying logic, converts a stock rod to be able to use a bushing, when anyone can buy a prepped con rod in a box ready to go! I would rather make more use of my time using shop tools that ARE needed and ARE used!
Perhaps I could use this more frequently! Any one need a piston fluffer, comes with dust!
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"Piston fluffer" ..Gets the piston ready for action? We had a piston knurler in our old auto shop as well as a brake shoe radius grinder. "No asbestos shoes allowed" in hand writing on a sign! would love to get a Sioux valve grinder with the lifter face grinder adapter.

@66fs How about a weekend car: Shows, donuts on a saturday morning, Ice cream runs? 1000 miles a year tops. I already have the pressed pins hung and balanced, just wondered if the teflon buttons were effective on a street motor.
 
I dunno, I have a set of stock rods out of a 360, thought about getting them bushed for floating pins, but forget it. Resized with ARP bolts is all I’ll do. I paid $60 for the bolts and it’s $88 bucks to do all rods. So $148 with rods ready to go, good enough for what I’m doing. I’ll be using the SpeedPro H116cp pistons. $300 to my door. It’s going in a ‘74 powerwagon.

Speed-Pro Hypereutectic Pistons H116CP 30
 
[QUOTE... @66fs How about a weekend car: Shows, donuts on a saturday morning, Ice cream runs? 1000 miles a year tops. I already have the pressed pins hung and balanced, just wondered if the teflon buttons were effective on a street motor.[/QUOTE]

Teflon is pretty soft. If it were me, I'd use a more conventional method. Pressed pins are good to go. No extra weight either.
 
@66fs I hate press pin rods, and I had some reconditioned floaters all ready to go and then I found the pistons I needed to use (and had already) did not have lock ring grooves for floaters so naturally I thought up a plan B. I know air-cooled get way hotter than water cooled so Teflon buttons was the other option. Ive since hung the pistons on the press fit rods with much drama: 2 are stiffer than the rest, piston hanger probably used a press (and not the specific spoon jig) to put those 2 on as he told me 2 were being very stubborn on standard hanging methods, ie heat.
 
@66fs I hate press pin rods, and I had some reconditioned floaters all ready to go and then I found the pistons I needed to use (and had already) did not have lock ring grooves for floaters so naturally I thought up a plan B. I know air-cooled get way hotter than water cooled so Teflon buttons was the other option. Ive since hung the pistons on the press fit rods with much drama: 2 are stiffer than the rest, piston hanger probably used a press (and not the specific spoon jig) to put those 2 on as he told me 2 were being very stubborn on standard hanging methods, ie heat.

They are not my favorites either. Just another reason I like 273's and 340's. They are really easy to work on. Unfortunately not all shops are created equal. There are dimensions for the pins (usually extremely close), rods, and the piston. They all need to be checked to go together and stay there. When I was single and poor, I would put the pins in the freezer, and the rods in the oven and put them together, but usually had to finish the job with a press. Where the pistons stiff on the pins before pressing together? My best guess is the small end of the rod is too far undersized or the pistons should have been sized for the pins? What engine are you working on?
 
I think the pin is fine but the pin boss edge in the piston got its edge deformed in the press operation (Probably used a socket or something as the support against the piston to press the pin into the rod instead of using the spoon jig to support the rod itself) I think I can correct These were magnum stroker pistons so no lock grooves hence the teflon button inquiry. When I pressed the pins out of these rods (old 360 pistons be damned) I used a 50 ton press with a electric pump in my fleet yards garage. I set them up and started the press and watched the pressure gauge build until the pins gave in with a pop...21 tons break away force! Pistons did not get damaged during that debacle, I thought for sure the pistons were gonna shatter under that 20 ton force between the rod sandwiching the lower piston side.
 
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I think the pin is fine but the pin boss edge in the piston got its edge deformed in the press operation (Probably used a socket or something as the support against the piston to press the pin into the rod instead of using the spoon jig to support the rod itself) I think I can correct These were magnum stroker pistons so no lock grooves hence the teflon button inquiry. When I pressed the pins out of these rods (old 360 pistons be damned) I used a 50 ton press with a electric pump in my fleet yards garage. I set them up and started the press and watched the pressure gauge build until the pins gave in with a pop...21 tons break away force! Pistons did not get damaged during that debacle, I thought for sure the pistons were gonna shatter under that 20 ton force between the rod sandwiching the lower piston side.

Wow! I've been cleaning things up and have no problem pressing 440 pistons off the rods with a 10 ton press. Usually the pins are within a few .0001 so maybe the rod small end should have been checked and honed to the right size?
 
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