Club Cobra - Rod and Main bearing clearances

Club Cobra (http://www.clubcobra.com/forums/)

- 429/460 Engine Talk (http://www.clubcobra.com/forums/429-460-engine-talk/)

- - Rod and Main bearing clearances (http://www.clubcobra.com/forums/429-460-engine-talk/87829-rod-main-bearing-clearances.html)

Rod and Main bearing clearances

It is time for me to buy my bearings for my 460/514 stroker build. I decided to go with KING Bearings. I plan for the motor to run no more than 6300-6500 RPM max. I was thinking .002-.0025 on the rods and .003 on the mains. Does this sound good or should I tighten it up a bit? What have you past builders run on your builds.

jetsbaby,

You're more likely to get helpful responses here: 460ford.com :: Index

Tom

Call Jon Kaase for numbers

jetsbaby I am not a pro with 429-460 motors. Jon would be the one to call and ask about the MAGIC numbers. For a street motor the clearances are geting smaller and the oil is getting thinner. If you are running a HV pump, and not knowing the Lima motor problems, I would go with a .0021-.0023 on rods and .0025 on mains. Find a blueprint builtup for a 460 and see what they are using. IMO the most important thing would be to add an Accusump to the car and oiling system. Use this as a per oiler before starting the motor and if you try a little autocrossing. 80% of engine wear is caused from dry starting motors. Get a bottle of EOS and on breakin run the motor at 2,000 rpm+ and keep the rpm at a steady speed. As the motor breaks in the rpm will go up, don't change the rpms. Good luck with the motor. Rick L. Ps old blue print numbers from the early 70's are .003" and .003" on rods and mains. this is for a RACE MOTOR for blue printing ONLY.:eek:%/ That's loose IMO. The motor only runs 600 miles and 7,800 rpms. Also alot thicker oil and additives.%/:)

The old rule of .001 per inch of shaft diameter still works pretty darned well. Truth is that as long as you are between .002 and .003 you'll be OK. My normal target for bearing clearances are around .0026-.0028. The bearing engineer that worked with me over my 12 years running Speed-Pro often said that "my phone doesn't ring if they're under .003 - if they're over .003 the phone starts ringing...".

Thanks

I am going to get my rotating assembly balanced and my block machine in the next month or so. The garage is like an oven here in AZ during the summer can't do any thing but order parts. :) I have recently done a lot of home work and I bought two sets of rod bearings and main bearings from King. Standard and .001 to tighten things up if necessary. I'll post my clearances when I get them.