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?)

[Superhawk996]

(IMG:style_emoticons/default/smilie_pokal.gif)

Congrats - while it’s apart don’t be afraid to play with the tools - all about feel.

Measure the same journal a couple times (no cheating by looking) by feel without watching the mic numbers. Write down the results. Get an idea of what your repeatability is.

Seriously - so glad it’s starting to make sense and that the numbers are plausible. (IMG:style_emoticons/default/aktion035.gif)