Not enough meat for a press fit? Do you mean the hole is too large? That would explain your problem.

1. I have never seen a wristpin bushing with steel backing. Ever.

2. There's no way in heck that Eagle or any other high performance rod manufacturer BRAZES a bushing into a connecting rod. Again, I have never seen it done in any application. Ever.

3. If Eagle uses a 0.0030" thick bushing there's no reason why you can't.

At 5000rpm, a stock dimension 440 piston exerts 5000lb of pull on the pin end of the rod. That's assuming an 1100gram piston and pin. If the wall thickness is 0.125 and the length is 1.1", the cross-sectional area of the pin end is 0.275 square inches. That computes to 18,182psi tensile stress.

Using Young's Modulus for 1541 steel of 28x10^6, the deformation of a 1.09" length stressed at 18,182psi is 0.0007". The press fit has to be greater than that. Steel elasticity is not dependent on its tensile or yield strength.

If you wish to float steel on steel, you will need an oiling hole on top of the pin end about 1/8" diameter with a small chamfer. I would suggest 0.001" clearance as a starting point, although others who know much more than I should be consulted first before setting that as ideal. The racing community started out with this as pin oiler, moved to two holes coming up from the bottom sides at an angle, but then moved back to the single hole on top of the rod. That is the latest configuration I have seen.

R.