71roadster

In this months Hemmings magazine there is on article on the last page about how to use a vacuum gage. Since this is a fairly inexpensive tool and the article touches on a couple of things I have seen on the forum I thought I would give a heads up. I'll be trying out a few of the tricks myself. One was to determine if your exhuast is to restricive.

There is also an article on the top 10 engine myths. Also relavent to a lot of discussions on the forum. Rod length, piston coatings, compression (diesel runs at 25:1!!!), detonation, etc...

gkull

So would you tell me about what they had to say about thermal coating, moly coatings, oil repellant coatings

71roadster

They said hot rodders and manufacturers are finally figuring out what the military has known for years. Thermal coatings on pistons and chambers not only reduce thermal loss, but also result in a faster flame front and more complete burn...hence more power and better efficiency and less build-up of deposits. The oil repellent coatings work to decrease the heat transfer on things like manifolds...which was another topic covered (more engineering than an airplane wing!).

I have been following the thermal coating technology just by grabbing industry mags or reading the adds in 'race car engineering'. This technology is really coming into its own and will be a critical part of future automobile technology. Not just in engines, but in bearings, brakes, and all sorts of stuff. They are figuring out how to do it right and cheap (the key factor for mfgs). The military can pay the big bucks to do it right without mass production.

Each of these topics was about a single column in length.

Jay M

That sounds like some great info. But when you say this month, do you mean August, or September?

Thanks!
~Jay

gkull

I was in a hurry and didn't research Thermal Coatings enough when I was building my motor this past spring. You should do the whole motor. I bought a light weight 40ish pound 3.750 forged 4340 crank and had it nitrided & oil repellant treated. My JE pistons I sent to a place and for $225 got the ceramic tops - moly sides - oil repellant bottoms. My Dart heads I didn't go far enoungh I had the chambers and exhaust valves done with ceramic thermal coating. You should also, after all the porting is done. Have the whole intake and exhaust ports done. So you don't have heat X-fer on the incoming or out going charge. I was leary of thermal coating my 2.08 titanium intake valves because the race shop had only seen thermal coated steel.

Next time I would also oil repellant the whole cam valley and everything under the valve covers. I should have also listened to the vendors about being able to run an addition .5 C/R I built my motor at 10.84 and should have made it mid to low 11-1 because I can't get it to ping on 92 octane with the recomended advance curve for high swirl fast burn technology heads.



[Modified by gkull, 2:50 PM 8/24/2001]

Rumpity Rump

Can you tell me the different ways to use the vaccuum guage in diagnosing., from the Hemmings article.? I just ended my subscription to Hemmings. Thanks,

Dave.