Re: Type 1 twin screw supercharger build / 9 yrs later I'm back at it

[Alexander_Monday]

Holy cow, almost 0.006" new?
That is over D × 0.0025.
I'd be sending them back, unless it was pro stock or top fuel.

Made a lot of aluminum swarf tonight.
Guess what they are:

[Alexander_Monday]

Wow, Speedway Motors doesn't mess around shipping, got the King CR 803XPN SBC small journal narrowed rod bearings today!

So nice when something measures exactly as advertised:
(I only opened the first package of 8 and all except 1 which was 0.0620")








Vs the Mahle CB-610A bearings:







This will give me 0.0017" clearance with 1.9991" journals which is D * 0.00085.







Unfortunately, I will have to make a jig to take 2mm off one side of each bearing.
Can't have my cake and eat it too, but my bad since they are advertised as 20mm wide while the Mahle's are 18mm wide)

[Alexander_Monday]

Designed a jig to narrow the bearings on the lathe.
3D printing it now.

[Alexander_Monday]

Jig worked really nice in the lathe.
Just a touch of chatter because it is plastic.

Before:







After:







I have another printing that is narrower to use to relieve the edges.

[Alexander_Monday]

Holy cow, almost 0.006" new?
That is over D × 0.0025.
I'd be sending them back, unless it was pro stock or top fuel.

Made a lot of aluminum swarf tonight.
Guess what they are:

BTW, the big aluminum jigs I made awhile back are for this:
(Not ready for that yet, but I have the jigs made)

[Alexander_Monday]

Cut down SBC small journal rod bearings before clean up in narrow 2nd jig







After file and stones to clean up

[Alexander_Monday]

Decision time.
Should I measure end play with tension on the crank or not?
What is acceptable for a flanged crank?
I have seen .005 to .008 preferred and .010 to .014 preferred.
This is a street warrior engine, not a drag race only engine.
Crank installed with Brad Penn assembly lubricant and case nuts tightened.

End play with 1/4" wrench turning big screwdriver against crank away from Flywheel end







Let tension off







Holding tension toward flywheel end







Let tension off

[Alexander_Monday]

From Mark Lawless:
"Your thrust measurement is right on the money."

[Alexander_Monday]

BTW, Pat Downs sells HP SBC small journal rod bearings already narrowed.
If I would have known, I would have bought them from him.
https://shop.patdownsperformance.com/products/bearings

[Alexander_Monday]

Long story short, the conversion stub axles rub on the inside of the trailing arm.
Putting a 30mm x 44.5mm x 0.5mm shim I found between the inner bearing and the inner race for the seal stops the rubbing.
I want to put 2 on each side but only found 3.
They were in with my VW saved stuff not used.
Anyone know what they are actually for so I can get more?

[panel]

Kinda look like swing axle washers that fit behind the seals.

[Alexander_Monday]

Are they that thin?
Someone else suggested the same.
Funny though, never had a swing.

[Alexander_Monday]

The second side took 2 to stop rubbing so I decided to use 2 for it and 1 for the other side.

Stub axles changed, freeway flyer out and KCR "best parts type 1" unboxed.

[Alexander_Monday]

Didn't get as far as I hoped, but transaxle installed, Bowden tube adjusted, shift coupler hooked up, stub axles installed.
CV's & axles another day, this old man is beat after lawn work, mowing, and working on this.

[Alexander_Monday]

Is this normal radial play for brand new parts?
It is total play for both sides.
The slop appears to be in the EMPI axle splines.