Hi Frank,
I was looking through my Spitfire 1500 Competition Preparation Manual and this
is what I found in the engine modifications manual.
"Use "Clevite 77" MGB rod bearings, Part # Clevite CB792P, in .010" undersize.
File the outside edge of the location tang on the bearings to fit the bearings
to the rods. Even though the bearings are quite a bit wider than stock, they
only need chamfering to fit. Grind the crankshaft to 1.8665" (about .009") to
get the recommended .002" clearance, Prepared in this way, bearing life will be
indefinite."
Granted they are talking about using the TR6 pistons and getting a lot more
power out of than stock. But I know that it has been recommended to me to use
the MGB bearings by a couple of Triumph gurus.
Roger Elliott
Frank & Sherry White wrote:
> Hello all...
>
> Some of you may recall a post several weeks ago from someone who had
> purchased a Spitfire in Phoenix, AZ, but lived in Kansas. Thanks to the
> responses from the list, I was able to get the car here with only one minor
> (story for another day) incident. Its now unloaded in my driveway and the
> motor is scattered around the floor on the garage. For the first few days,
> all I did was wander into the garage, look at the pile of parts, then return
> to the house to ponder life in a mental institution. Since then, I have
> made quite a lot of headway cataloging and inventorying parts and feel much
> better about the project. Thanks to the Wichita (KS) British Car Club, who
> had a show in McPherson last weekend. Seeing a bunch of assembled LBCs got
> me started.
>
> The motor should be ready to go to the machine shop in a week or two. I do
> have a few questions before hauling the whole mess in. The machine shop is
> going to clean the parts (lots of surface rust, parts had been on the boot
> and rain), verify that the block is the correct bore for .040 pistons and
> rings, enlarge old galleys, verify measurements and balance everything. I
> received the motor in pieces, along with many new parts. There is a set of
> .010 main bearings among the new stuff. The crankshaft does not appear to
> have been machined. It has been recommended that I install MGB main
> bearings rather than Spitfire bearings, because the MGB bearings will
> provide a greater surface area, fewer troubles, etc. My plan is to order a
> set of .010 MGB bearings and take them to the machine shop so that they can
> measure the actual part that will be used. Would anyone use a different
> approach?
>
> I also have three thrust washer sets, one standard, one .005 and one .015,
> presumably to judge which one is the best to use during assembly, or should
> this be addressed by the machine shop?
>
> I think that's all for this evening....thanks for listening!
>
> Frank White
> McPherson, Kansas
> 1998 Acura Integra GS-R
> 1997 Chevy S10
> 1995 Triumph Sprint
> 1989 Honda CRX HF
> 1984 Moto Guzzi V65SP
> 1974 Triumph Spitfire
> 1972 Yamaha AT2
>
> "Speed doesn't kill. Its the sudden stop that gets you!"
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