is it ok for the rods to have a little bit of play on the crank? has anyone else put eagle rods on an STi/WRX and had them not sit completely "snug"?

im wondering if i need oversized bearings or not because of the clearence on the crank/rod

someone chime in and let me know if i'd be safe runnig it as is with this clearance.


eagle rods
cosworth rod/main bearings

-alan

do you have any way to measure the clearance?

i would expect a small amount of clearance for oiling, but it shouldnt be anything you could really feel

what were you clearences on the rods did you use plasti-
guage i would def use cosworths or acl specs.

If you can feel the rods "playing" on the crank, then thats WAY too much clearance!!

If you can feel the rods "playing" on the crank, then thats WAY too much clearance!!

To describe a little better.

You should have Thrust (side to side clearance/movement) this also should be measured.

With bearing shells installed in the rod ends and either oil or assembly lube applied you should not be able to feel any play forward to backward (bearing surface to opposite bearing shell surface) ..... This also should be measured.

- J.

Yeah I should have clarified....if you think the bearings might be the wrong size and you are feeling foward/back movement of the rod, then that is bad.

You'll know its bad when you start the car and the engine clunks like a jackhammer, and flogs the bearings out within 20 seconds. :eek:

Plastigauge is a quick way to tell straight away if the bearings are the right size, but you should really mike the inside diameter of the bearing shell installed in the rod, and also the outside diameter of the journals, and the difference will be your clearance.

Also, have you had your crank machined or linished at all? Cosworth bearings only come in a standard size, so if you did have the crank worked on at all, there is a good chance that you'll need undersized bearings

ok, got it all straightened out.. jonathan @ world1 perf. worked it all out for me.... seems that cosworth doesnt really like the Eagle rods and told him that in order to use those rods with their bearings i'd have to use the standard sized bearings.

yeah, i didnt know i had the "race" bearings which are thinner than the standard. today we put some factory STi rod bearings on to see how it'll fit and it fit snug (no play).

I'd like to thank Jonathan @ world one performance for hooking it up and sending me the right bearings (not that we knew that these wouldnt work, but thanks for fixing it for me)

-alan