[Jeff Walker]

Also in regard to the oiling I see that the oiling hole for the wrist pin appears to be pretty good sized. Aslo it looks to have a dish shape around it to help capture more oil.

It it interesting to find they made a full floating setup without a bushing. Before seeing this I would have put up a pretty good aruguement that nobody ever did. Of course who knows what good this new knowledge will ever do for me.

[onetru462]

I have thought over this for awhile, and this is the only thing I can come with. As far as worrying about the powder, or two metals forcing against one another, the wrist pin is easily allot denser material than the rod would ever be. I can't really imagine the rod being able to hurt the pin, and the finish on the pin would make it hard to hurt the rod. I am also thinking that the enlarged hole at the head of the rod is that size to keep the constant flow of oil to it. I am also sure my example a straight motor is to a v based motor isn't apples-to-apples as the side loads are allot different (right?). Second, if the pin did seize in the rod end, how would that actually hurt anything? It would then be like a pressed pin, correct?

Again thanks for the responses, I love how this forum continues to make me think or look at things so differently. Allot of fantastic knowledge roaming around here.

[Jack Gifford]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> if the pin did seize in the rod end, how would that actually hurt anything? It would then be like a pressed pin, correct? </div></BLOCKQUOTE>

Good point!

[Half-Inch Stud]

Er ah,

1. Inline motor slugs have the same sideload skirt issue as the V8 slugs.

2. Like a pressed-pin...Hey, there's a thought.
Thanks for making me point more clear than I could.

sooooo, the "remaining issue" is: what is the best, most reliable, preferred way to keep the Pin located within the Slug? Suppose the choise is Pressed-to-Rod or endclips (spiral, C-clips, Rollpin, etc).

Hmmmmm.....having both may not be as reliable as pressed for Street. While Pressed may not be as reliable for Strip. There ya go:
----------------------------------------------
Street,Street/Strip: pressed

Full High RPM Race: floated pin with endlocks.
Assuming the advantages are improved tear-down capability and more tension load handling for the litle end.

[onetru462]

Thank you for the input on side loading. I wasn't sure of that, kept over thinking it what with the off set pin location. Didn't think the inlines would have that or how it would effect it.
I am not sure about the way you took my point on the pin seizure. I was supposing worst case if it happened is all.

What I have taken from the discussion is there doesn’t seem to be a reliability issue that has been shown, so most likely it was a "bean-counters" decision to use the press fit as there is less machining and materials involved. I can imagine there really being a performance advantage either if the weights are the same as the no mater how the pin is installed, the piston floats on the pin either way. So from there I can only see a preference by ease of installation, and using the parts you have.

Main point that I was trying to find was the reliability of honed ends vs. bushings, not the use of floating pins. I am glad I was able to just do a rod swap, and after this much thought in it I would believe I would put the bushings in as there must be a reason for them to be used longevity wise.

Thanks all.

[Half-Inch Stud]

My hunch about side-locking a floating pin is one lock would get constant Pin end-loading and wear away (lathe their way out) the Slug groove in the Street application.

[onetru462]

Good point!And I suppose the forces involved would be extreme which I sure they are at that end of the rod. I wish now I had looked at my Quad when I had it apart. Never occured to me to look at that detail. Will look next time that is for sure. As a matter of fact, when I do the head swap on this motor later in the season I would only be a rod bearing away from checking one to see. Is this maybe the reason why they drill a hole in the oil ring land that intersects the pin area of the piston (actual ? as i have wondered just why they are there, not a sarcstic ?)? To keep extra oil at that point to keep this from happening? I did notice my TRW's didn't have that hole, but the ones in my Quads and the Venolia pistons I am using now in my poncho do. Thanks for the insight on this HIS. I have read alot of your posts, and I appreciate how quick to the point you most often are.

[69v8tr6]

I have run a set of 1967 cast oil squirter rods full floating with no bushings since about 1992.
I drilled holes in the top like the rods pictured.
No problems yet,have used as much as 175 HP of nitrous, but keep the RPM under 5800. Don't know if I would run a steel rod with no bushing as it is a lot harder than a cast rod.