2270 Build thread, Looking forward to making all of the mistakes! Options

[vjb206]

Hey folks! I've got...

• Case halves from an old 1.7 (cleaned as best I could)
• 2270 crank + P&C kit
• #163/86b Web Cam
• 2.0 heads with 44X36 valves, where I'll be installing dual springs and 38mm exhaust valves
• Upgraded oil pump and other goodies

So my first question for the community has to do with ensuring the rotating mass is spinning freely/correctly…

I started by measuring all of the the main journals on the crank and I got a range from 2.358” - 2.360” (I used a digital caliper and I'm pretty sure I did this correctly).

Then I “dry-fit” Silverline STD/STD main bearings into the case (sans crank), torqued everything down, and got 0.003” in radial play (I used a cylinder bore dial gauge for the first time, and I think I did it correctly).

The spec-sheet says radial play should be between 0.06” - 0.10” (0.03” - 0.09” for #2); and I have 0.003." I'm a MINIMUM of 0.057" off, is that normal? What's my next step?

1. Stop pretending I know what I'm doing and take it to a machinist for test-fitting and honing (I'd like to keep cost down so this is my less preferred option)
2. DIY: hone 0.06" off all bearings (what's the right honing tool / approach here?)
3. Order different bearings (if so, which?)

[technicalninja]

That's the way...


Plasti-gauge can only be used on split bearings. The single piece bearings have to be measured.


It's HARD to properly torque up a rod without moving it.

The tiniest movement destroys the accuracy.

They missed some important tips.

Make your length of plasti-gauge that you're inserting in the journal slightly narrower than the bearing width. It's best to have .020" (.5mm) on either side of the strip or you will have a harder time cleaning the PG off of the bearing and the crank. The radius corners squish the piss out of plasti-gauge; try to keep it out of the corners.

It is IMPORTANT to carefully remove the plasti-gauge after testing completely.
I use soft rags, WD/40, alcohol, and a soft touch. The inner surface of an engine bearing is extremely soft. You can scratch it with your fingernail.
Don't damage this surface when cleaning.