Question about con rods

[GeoffP]

I'm wondering what the benefits of a full floating wrist pin are over a press fit pin? Since I'm building a street/strip engine, do any of ya'll have any compelling reasons for me to go with a floating pin rod over a press fit pin rod? TIA

[CraigSkiles]

Easier to assemble the floating wrist pins.

[GeoffP]

Craig, did you build your engine with floating pins? I thought that floating pins had to be honed to size by hand to get the pins to fit just right?

[ragtop88]

Easier to Assemble?? You must not have had to play with the spirolocks... :D I'm not sure what the differences truely are, but the floating you can assemble and disassemble numerous times if you need it without fear of damaging the piston or rod in the process...the end of the connecting rod does have to be honed to the correct diamter, but any competent machine shop should be able to handle that.

[GeoffP]

I found the 2-icr6000p at http://www.flatlanderracing.com/cribeamscat.html for $219.00. I'm probably going to check this place out. The next lowest price I've found is $245.00 at Sallee Chevrolet. Unless I hear any compelling arguments for one style over the other, I'm probably going to go with press fit just because that's what I've always worked with and it's what I know.

[CraigSkiles]

Yes, I used floating rods. The Eagle Rods I got were already honed by the time Ball Enigne got them. What Ball engine did was finished honed them to the JE wrist pins.
The first rod assembled to the piston was a bastard with the spirolocks. A hint that if you do go with the floating wrist pin, spread out the locks a little bit then use a small screwdriver to insert the lock. After that, it made the whole assembly much easier. smile.gif

Craig

[GeoffP]

I'd say based on what ya'll have just posted, that I'm just going to get the press fit rods. Since I'm having a hard time finding a local machinist that can balance my rotating assembly, I'd rather not have to through more difficulty into the build up at this point. Thanks guys!

[Jeremey]

Rods designed to be used with floating pins actually use a bonze bushing in the small end. Your pistons must be designed to use floating pins and have the groove for the locks to seat in. Floating pins are primaraly used in all out racing and allow the engine to rev easier and slightly higher.

[Hammer]

Geoff, In my opinion the only reason to "full float" a piston rod assembly, is to engineer just one more clearance into your motor to loosen up and knock later on. Just one more thing to go wrong, so to speak. The real benefit of the full floater is ease of installation....(like if you "cook" a piston at the track)....pull the pin, put on a new slug. I've built some pretty tight motors, and haven't had a problem with my preferred method yet. Although, I have seen the aftermath when the other method was used(spirolocks coming out, getting lodged in the oil pump- knock, knock...the pin sliding out, rubbing on the cylinder wall, wearing a 1"x1/8" groove in an otherwise perfect block....you get the picture.) Less maintainence, less money, same function......you make the call ;)
Hope I shed some light on the subject,
-Hammer-