1174Re: 390 blueprinting
- Jun 4, 2004---Greg,
I find it odd that any mechanic that works on any kind of engine
would make that comment about it being "old iron". Blueprinting,
which is simply checking all the clearances to factory specifications
is no more difficult on a Caddy 390 than any other engine. Actually,
most parts ordered fall within these specs but should be checked
while assembling the engine. I have five Caddy 390's in 3 1959
Caddys, a 1961, a 1962, and they are no more difficult to rebuild
than any other motor.
Rod and main bearings in most all motors have a clearance of .002
inch, crankshaft journals should be checked for any out of round
condition with a micrometer, and basically any correct engine
building process would be called blueprinting. It is inconceivable to
me that any mechanic would simply assemble the parts in an engine and
not check any clearances, but evidently it is done all the time. Most
general repair shops these days just seem to see how fast they can
slam the jobs in and out.
I have built a lot of oddball engines for years. One of the rule of
thumb practices regarding having a crank remachined is if your
fingernail catches on any bearing journal surface, it should be
machined to the next oversize bearing, most generally .010 inch, .020
inch, or .030 inch.
If you have some questions, please e-mail me at hottrod41@...
I also have a website up at http://geocities.com/hottrodscars
Also for parts availability, I have subscribed to Hemmings Motor News
for about 30 years. Their online site is http://hemmings.com
In Cadillac_Performance_Association@yahoogroups.com, "rockinrye"
> Can anyone recommend someone in the Northeast to blueprint a 390?
> I may even be interested in some custom work.
> Most shops I've asked just shake their head and comment that its
> some pretty old iron... They are just looking to bang out SBCs.
> I'm looking for someone that has some experience with these motors
> and the right equipment.
> Much appreciated,
- << Previous post in topic Next post in topic >>