Rods from Common Block

[BLASINTEBO]

Will rods from a common block 89 shelby, fit my earlier crank (86 T1)?

I want to upgrade the rods, and don't know whether to get

PN 4323957,

or PN 4387699

I definitely don't want to keep the LW rods.

[BLASINTEBO]

Ttt

[slasky]

yes. My old 87 block had common block rods in it.

[22dodge]

Rods in the common block are 5.94" long. rods from all 2.2's from 1981-1994 are 5.94" long. however the 1981-1984 rods are beefier. In my racing program were stock rods were required I used the older rods or I would use the long 2.5 rod depending on track applications. I found on the longer tracks that the long rod worked better while on short tracks with tight corners the stock 5.94 rod was a better choice

[slasky]

the 81 to 84 were press pin and all the t2 and t1 common blocks were floating pin. The floating pins really don't offer any performance gains but the mahl and most forged pistons require them.

[22dodge]

I did some research with an R&D guy at Mercury Marine. The conclusion is that press vs float made no real difference. the only advantage was disassembly.

[BLASINTEBO]

How can I tell the pressed pin from floating pin?

The guy who sold me the rods told me they would be TII rods, but I think they are 81-84 rods... they look beefy up top, but the caps look like the T1 caps, without the extra material there, shown on thedodgegarage.com .

I told him these weren't the rods I expected, he replied and said to tell him the xact year/model I want them for.

IF I said 89 CSX, maybe Ill get forged?

[22dodge]

floating pins have a bushing in the pin end with a oil feed hole.

[mr_v8horsepower]

Ask for a '89 2.5L Turbo Rod. They are the same as the T2 rod and standard equipment on the 2.5L t1 engine in '89. They have the bronze bushing and oil hole mentioned in the post above and the beefy cap.

[tonyz2897]

With all this discussion about rods, I'm just curious what the change was that finally got rid of that annoying wrist pin noise in higher milage motors? I've heard a good bit of talk about it with early t1 stuff, but not much mention of it regarding the later model motors. Heck, if that was all the floating pins were good for, then they're ok in my book.
Tony

[glhsken]

It was the change to floating that solved it.

[tonyz2897]

Quote:

Originally Posted by glhsken It was the change to floating that solved it.

Good deal! So the '89 2.5 I'm getting ready to rebuild actually stands a chance of not making embarassing noises. Cool!
Seriously though, I was pretty well convinced for awhile that wrist pin noise was just a myth that was used to explain knocking due to worn bearings/low oil pressure. That was until I pulled the '88 2.2 in my Daytona apart (sounded like a diesel) and discovered that the bearings were in halfway decent shape.
Tony

[22dodge]

full floating pins (not offered in any non-turbo chrysler engines) does NOT solve pin wear. The main issue is starting circa 1988 the pistons went to a hyperuetectic design which has a very high silicon content in the aluminum this creates a high resistance to wear. in fact the silicon will actually wear out the steel of the pin creating a knocking noise. I actually pulled one engine apart that had over .050" wear on the pin other than the horrid noise, the engine was still in excellent running condition. I just tossed in a good set of select used wrist pins, re-used the original bearings/rings and that engine is still running strong miles @ 300,000+.

[puppet]

Just want to point out that not all forged rods have an oil hole in the small end. I wouldn't use that as an identifier.

[BLASINTEBO]

The only rods that are forged are the 89 Shelby ones right?