Crankshaft balance

[abripl]

Its not much flying time around here in SD with temps averaging 0F.

I got my engine (Franklin 6) apart trying to cure a vibration problem
(0.4 IPS) - not extreme but anoying. Is it OK to balance the crank in a
automobile machine shop or are there some tricky things about aircraft
cranks? I know automobile cranks go to 6000 rpm and my aircraft crank
only goes to about 2800. So auto shops should be able to do a more
precise job?

[stol]

If it is in an experimental plane then a good auto machine shop can
probably do a better job then most "certified" aircraft shops. You can
check most of the weights, ie; pistons, rings,pins bearings, rods,,
yourself with a good gram scale. If you do get it balanced please post
back here to let us know how far out it was.

Ben.
www.haaspowerair.com


abripl wrote:
> Its not much flying time around here in SD with temps averaging 0F.
>
> I got my engine (Franklin 6) apart trying to cure a vibration problem
> (0.4 IPS) - not extreme but anoying. Is it OK to balance the crank in a
> automobile machine shop or are there some tricky things about aircraft
> cranks? I know automobile cranks go to 6000 rpm and my aircraft crank
> only goes to about 2800. So auto shops should be able to do a more
> precise job?

[Fly]

I'm curious about how you have 0.4 ips vibration problem?
Are you sure its the crankshaft?

Sorry, I disagree that automotive people can do a better job.
How many auto shops check the nitriding and heat treatment?

Pistons and rings are not part of crankshaft balance.
Pins bearings?

Kent Felkins
Tulsa



"stol" > wrote in message
oups.com...
> If it is in an experimental plane then a good auto machine shop can
> probably do a better job then most "certified" aircraft shops. You can
> check most of the weights, ie; pistons, rings,pins bearings, rods,,
> yourself with a good gram scale. If you do get it balanced please post
> back here to let us know how far out it was.
>
> Ben.
> www.haaspowerair.com
>
>
> abripl wrote:
> > Its not much flying time around here in SD with temps averaging 0F.
> >
> > I got my engine (Franklin 6) apart trying to cure a vibration problem
> > (0.4 IPS) - not extreme but anoying. Is it OK to balance the crank in a
> > automobile machine shop or are there some tricky things about aircraft
> > cranks? I know automobile cranks go to 6000 rpm and my aircraft crank
> > only goes to about 2800. So auto shops should be able to do a more
> > precise job?
>

[abripl]

> I'm curious about how you have 0.4 ips vibration problem?

I had it tested at an FBO that does prop balance and they found about
0.2 ips at the prop (FAA acceptable) and about 0.4 (+?) ips at the
other end and told me it was the engine.

> Are you sure its the crankshaft?

I didn't actulally say it was (only) the crankshaft. But as Ben said I
could probably do the pistons/rods myself with a good scale. But
balancing complex rotating masses like a crankshaft requires a proper
machine.

> Sorry, I disagree that automotive people can do a better job.
> How many auto shops check the nitriding and heat treatment?

The issue is balance not other engine work. Auto shops balance engines
to 6000+ rpm redline, whereas aircraft engines redline only to about
2800. Search through this group and you will find some interesting
discussions about lax approach to balance by Lyc. etc.

> Pistons and rings are not part of crankshaft balance. Pins bearings?

???

The whole engine balance is made up of pistons, rods, bearings, rings,
crankshaft, moving masses which need to balance together.

[Fly]

> I had it tested at an FBO that does prop balance and they found about
> 0.2 ips at the prop (FAA acceptable) and about 0.4 (+?) ips at the
> other end and told me it was the engine.

R1.... .2 ips is 'faa acceptable' but any tech should be able to get it
below 0.1 ips.
Sometimes I see a cross-effect in which the rear is running big because
of a prop being installed in an angle that is not optimun. Another factor
is the static weights on the prop itself. The adjustment may resolve an aft
imbalance. What was the phase angle difference?
However in most cases it is a crank or rod imblance that is probably
causing it.



>But as Ben said I
> could probably do the pistons/rods myself with a good scale. But
> balancing complex rotating masses like a crankshaft requires a proper
> machine.

R2. You need more than a scale for the rods. A rod is suspended by each
end and in turn the big ends and the small ends are weighed, the C.G. is
deduced. In other words the rotating and the reciprocating masses are
measured. Auto guys will then make up a bobweight of nuts and bolts
equal to the rotating part which they add to the crank throws and that is
then spun on a dynamic balance machine.



> > Sorry, I disagree that automotive people can do a better job.
> > How many auto shops check the nitriding and heat treatment?
>

R3: The issue isn't RPM unless you are relating to 'flexible or
non-flexible rotors'
Typically Auto cranks are balanced by drilling the counterweights a little
deeper or what ever.
I can't say about Franklins, but Lycomings and Continentals do not have
counterweight molding in
the casting because the arrangement is a 'balanced' engine in the 1`st order
by design.


In the 'approved' after market, Lyc and Cont cranks are further balanced
the same at the mfg does but to a finer degree.
in my experience, it hasn't been whether is the balance is better than '3
mils' as the factory print specifies, but rather it has been making sure
you do have not a sloppy part with some 40- 80 gram-inches imbalnce that
slipped out the door!

good luck

Kent Felkins

[abripl]

>...Auto guys will then make up a bobweight of nuts and bolts
>... equal to the rotating part which they add to the crank throws and that is
>... then spun on a dynamic balance machine. ...

Yes. Thats true for V8's or V6, etc. But not needed for opposing cyl
engines.

>.. I can't say about Franklins, but Lycomings and Continentals do not have
>... counterweight molding in the casting

Its the same for the Franklin - its an opposing flat 6. Opposing flats
are inherently easier to balance.

[abripl]

On last comment... That's one reason why opposing flats are lighter
engines not needing the extra counterweights.

[stol]

I'm curious about how you have 0.4 ips vibration problem?
Are you sure its the crankshaft?


Sorry, I disagree that automotive people can do a better job.
How many auto shops check the nitriding and heat treatment?


Pistons and rings are not part of crankshaft balance.
Pins bearings?


Kent Felkins
Tulsa

////////////////////////////////////////////////////////////////////////////////////////////////////

Let me set some things straight for ya. Any good racing machine shop
can balance a motor far better then the vast majority of FAA approved
places. In fact Lycoming can't even built a crank for some models they
produce that won't break, and they have killed people this way. So much
for the FAA keeping a close eye on quality... As for nitriting and heat
treating, this is an every day detail in the racing market and is down
to a science, not black magic... Pistons and rings and circlips are
part of the rotating/reciprocating assembly and need to be balanced
too. Good shops even add in a factor for the weight of oil that clings
to the balanced mass to get it perfect.

[stol]

R2. You need more than a scale for the rods. A rod is suspended by
each
end and in turn the big ends and the small ends are weighed, the C.G.
is
deduced. In other words the rotating and the reciprocating masses are

measured. Auto guys will then make up a bobweight of nuts and bolts

equal to the rotating part which they add to the crank throws and that
is
then spun on a dynamic balance machine

///////////////////////////////////////////////////////////////

This is correct to a point. I have balanced more engines then I care to
remember and I have never had a motor where I didn't weigh all the rods
as is. For instance if you have 8 rods and 7 weigh in at 580 or so
grams and one weighs 640, you can grind /machine /rub / pray,,, what
ever you want to do there is no way you can remove from the big end or
small end to get "that" heavy rod balance with the other seven. So the
point I was making is one could gram out the parts at home to find out
pretty darn fast is they have a bad match of stuff. Once the motor gets
to a quality auto machine shop they will put the rods on a fixture and
duplicate big end and small end weights.

[stol]

R3: The issue isn't RPM unless you are relating to 'flexible or
non-flexible rotors'
Typically Auto cranks are balanced by drilling the counterweights a
little
deeper or what ever.
I can't say about Franklins, but Lycomings and Continentals do not have

counterweight molding in
the casting because the arrangement is a 'balanced' engine in the 1`st
order
by design.


/////////////////////////////////////////
Look close at the Lyc / Cont cranks and you will see balance marks on
the rod throw end. As you have pointed out they don't have counter
weights so thats the only logical place to correct a large imbalance
that happens during the crank forging process.

[Fly]

"stol" > wrote in message
ups.com...
> I'm curious about how you have 0.4 ips vibration problem?

> Pistons and rings are not part of crankshaft balance.
> Pins bearings?
>>
> Let me set some things straight for ya. Any good racing machine shop
> can balance a motor far better then the vast majority of FAA approved
> places. In fact Lycoming can't even built a crank for some models they
> produce that won't break, and they have killed people this way. So much
> for the FAA keeping a close eye on quality... As for nitriting and heat
> treating, this is an every day detail in the racing market and is down
> to a science, not black magic... Pistons and rings and circlips are
> part of the rotating/reciprocating assembly and need to be balanced
> too. Good shops even add in a factor for the weight of oil that clings
> to the balanced mass to get it perfect.


Well Excuse meee..........!!!!

Circlips? Are you referring to piston pin circlips? They are not used in
Lycomings or Continental aircraft engines.
Tell me which models of Lycomings break cranks? I don't want to fly behind
those.

I'm still wondering what the pin bearings are.

Please direct me to to a engineering reference or paper that discusses the
factor that discusses the weight of oil that clings to the balanced mass.
Otherwise that is somebody's guess.. their own black magic.
Kent Felkins

[Fly]

"stol" > wrote in message
ups.com...
>
>
> R2. You need more than a scale for the rods. A rod is suspended by
> each
> end and in turn the big ends and the small ends are weighed, the C.G.
> is
> deduced. In other words the rotating and the reciprocating masses are
>
> measured. Auto guys will then make up a bobweight of nuts and bolts
>
> equal to the rotating part which they add to the crank throws and that
> is
> then spun on a dynamic balance machine
>
> ///////////////////////////////////////////////////////////////
>
> This is correct to a point. I have balanced more engines then I care to
> remember and I have never had a motor where I didn't weigh all the rods
> as is. For instance if you have 8 rods and 7 weigh in at 580 or so
> grams and one weighs 640, you can grind /machine /rub / pray,,, what
> ever you want to do there is no way you can remove from the big end or
> small end to get "that" heavy rod balance with the other seven. So the
> point I was making is one could gram out the parts at home to find out
> pretty darn fast is they have a bad match of stuff. Once the motor gets
> to a quality auto machine shop they will put the rods on a fixture and
> duplicate big end and small end weights.
>

gee.... a fixture... What does a quality auto machine shop use? A CNC
machine?

Kent Felkins

[Fly]

"stol" > wrote in message
oups.com...
>
> /////////////////////////////////////////
> Look close at the Lyc / Cont cranks and you will see balance marks on
> the rod throw end. As you have pointed out they don't have counter
> weights so thats the only logical place to correct a large imbalance
> that happens during the crank forging process.

Yes, you have noticed the factory and aftermarket balance marks. Have you
ever checked the depth of material removed? How deep is the nitride layer
usually?
What do you do about the bifilar dampers that most higher horsepower
crankshafts have?
It is a misnomer that these are commonly called crank counterweights.
You install new bushings and rollers? Do you balance with them
installed on the crank? What about a Lycoming ring gear?

btw, thanks your three posts in "setting me straight".

Kent Felkins
Felkins Aircraft Ltd.
FAA CRS WNKR918K
Tulsa Oklahoma

[Fly]

"stol" > wrote in message
oups.com...
>
> /////////////////////////////////////////
> Look close at the Lyc / Cont cranks and you will see balance marks on
> the rod throw end. As you have pointed out they don't have counter
> weights so thats the only logical place to correct a large imbalance
> that happens during the crank forging process.

Yes, you have noticed the factory and aftermarket balance marks. Have you
ever checked the depth of material removed?
How deep is the nitride layer usually?
What do you do about the bifilar dampers that most higher horsepower
crankshafts have?
It is a misnomer that these are commonly called crank counterweights.
You install new bushings and rollers? Do you balance with them
installed on the crank? What about a Lycoming ring gear?

btw, thanks for your three reply posts for "setting me straight".

Kent Felkins
Felkins Aircraft Ltd.
FAA CRS WNKR918K
Tulsa Oklahoma

[stol]

Kent Felkins
Felkins Aircraft Ltd.
FAA CRS WNKR918K
Tulsa Oklahoma

/////////////////////////////////////////

I was just giving out my two cents worth. After all this is the Rec,
Aviation, " HOMEBUILT" site. I would never post something like this on
the rec. aviation "certified" site. After all the FAA knows all.I still
think Lycoming murdered 13 people by selling a inferior product and the
FAA was in bed with them the whole way. I have owed several certifeis
planes in my life and I never want to see a yellow tag again. Those
things have tried to kill me a couple of times and the funny thing is
the Feds didnt even investigate the repair stations involved. Now I
will head at and fly my homebuilt plane powered by a Firewall forward I
designed and built. The air is good and thick at -34f. Peace and Merry
Christmas from Jackson Hole Wy

Ben
www.haaspowerair.com

[abripl]

Here is some more discussion about balancing:
http://groups.google.com/group/rec.aviation.homebuilt/browse_frm/thread/e0d8cbc797f49c75/a29345c98a2408b1?q=crankshaft+balancing+balance&rnum=2#a29345c98a2408b1

[stol]

here are some links to the Lyc mess. I am amazed you are in the
industry and have not heard of this fiasco..

www.bizjournals.com/wichita/ stories/2005/02/14/daily30.html

[stol]

Another link to bad cranks....

eaa563.org/Newsletters/ 2002%20News%20Letters/0203/vol9issue3.pdf

[stol]

more bad "CERTIFIED cranks

www.machinedesign.com/ASP/viewSelectedArticle.
asp?strArticleId=58969&strSite=MDSite&catId=0 -

[stol]

Better yet just google " Lycoming crankshaft recall" Your sig line
shows you are a FAA repair station.. Ya mean the feds didn't notify you
of this major failure???



Kent Felkins
Felkins Aircraft Ltd.
FAA CRS WNKR918K
Tulsa Oklahoma

[Fly]

Abripl,

I lost the messages that began this thread so I forget whether you had a 4
or 6 cyl. I also do not remember if I asked you about your prop position.

I stopped by Aircraft Specialties Services today. I looked at several
Franklin cranks and some rods.

Anyway, for one source, if you decide to send your crank and rods off for
balancing, talk to Harold or Bobby at A/c Spec. 800--826-9252
$115 for the crank balance and about $45 for the rods.


If you have any questions which I can help you with, you are welcome to
email me directly.

The bigotry expressed by others in this thread is bordering on getting
personal. I am going back to lurk mode.

good luck
Kent Felkins



"abripl" > wrote in message
ups.com...
> Here is some more discussion about balancing:
>
http://groups.google.com/group/rec.aviation.homebuilt/browse_frm/thread/e0d8cbc797f49c75/a29345c98a2408b1?q=crankshaft+balancing+balance&rnum=2#a29345c98a2408b1
>

[Fly]

ah ... those dastardly engines!


http://www.ntsb.gov/ntsb/brief.asp?ev_id=20050119X00071&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001212X22244&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001212X21584&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001212X18865&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001205X00509&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001205X00196&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X10959&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20051118X01860&key=1

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20051004X01567&key=1

[stol]

Anyway, for one source, if you decide to send your crank and rods
off for
balancing, talk to Harold or Bobby at A/c Spec. 800--826-9252
$115 for the crank balance and about $45 for the rods.


If you have any questions which I can help you with, you are welcome to

email me directly.


The bigotry expressed by others in this thread is bordering on getting
personal. I am going back to lurk mode.


good luck
Kent Felkins



"abripl" > wrote in message


Bigotry ???????? Hmmmmm. And I thought this was the rec.aviation.
"homebuilt" list? Of course we are suspect of the feds silly rules.
Look at their track record.. After all they are only 7 TRILLION dollars
in debt.

One more thing, if this is the Bobby I have heard of ,you better mark
your crank in a discreet place because he has been known to swap
customers good cranks for ones he has laying around that are of "lesser
quality". That way he can resell your good one and make a nice profit
and you get back a P.O.S.....

Happy Flying...

[abripl]

Ben,

I got a word from the machine shop. They say they can balance the crank
- about 5 g off on one end and about 8 g on other end. But they are
worried about the pistons and rods. Pistons about 5 g off and some rods
about 5 + 3 off. They will try to do the best but cannot take that much
alum off the pistons.

[abripl]

>... make some hard, expensive choices.... or live with .. part....

They will get it as close as they can. The engine was about .4 ips
imbalanced to start with - not so terrible, FAA certified limit is 0.2
ips. Any improvement will certainly help and may bring it within the
0.2 ips. Remember that this engine redlines at 2800rpm compared to an
auto engine at about 6000rpm. The same mass imbalance forces are one
quarter that of an auto engine.

There are some tricks that can be done:
A.) for heavy rods big end - cut off four of the six castle nut crowns
to save almost 2 g or use a longer heavier nut with a slot where the
cotter pin goes to add 2 g to light big ends = a difference of 4 g.
B.) We will also look at matching light pistons with heavy small ends
and heavy pistons with light small end.

My engine is listed as EXPR-OTHER and not as not as a certified
Franklin - required 40 hours test time. This allows using a little
ingenuity to solve such problems.

[Morgans]

"abripl" > wrote in message
oups.com...
> Ben,
>
> I got a word from the machine shop. They say they can balance the crank
> - about 5 g off on one end and about 8 g on other end. But they are
> worried about the pistons and rods. Pistons about 5 g off and some rods
> about 5 + 3 off. They will try to do the best but cannot take that much
> alum off the pistons.

It sounds like you are about to make some hard, expensive choices. New
pistons and rods, or live with at least part of it, is what it sounds like,
to me.

That is a lot of difference, don't you think?
--
Jim in NC

[Fly]

">
> "abripl" > wrote in message
> One more thing, if this is the Bobby I have heard of ,you better mark
> your crank in a discreet place because he has been known to swap
> customers good cranks for ones he has laying around that are of "lesser
> quality". That way he can resell your good one and make a nice profit
> and you get back a P.O.S.....

I said I was going back to lurking, but I am coming back to this slop
trough for one more post.

I've watched this group for over ten years and occassionally have seen a
contributor who is sharp and experienced in their field and is willing to
relate their knowledge. Its like finding a diamond's in a goat's butt.
Other times though I just find a goat's butt.

This thread started out about some guy writing about franklin engine
vibration and crankshaft balance. I joined in to offer my opinion from my
18 or so years experience in the field.
And I get bashed for being FAA certified.
Then I infer I was could bring to this thread the experience of a
nationally known and well-respected firm who actually does the work on the
said type of crankshaft and connecting rods.
And somebody says the firm is a crook and rips off their customers.

The firm I am talking about has been in the business for close to 30
years and is still thriving and expanding. My business is thriving
too. You don't achieve that by ripping people off.

Parts trading is well known trick in in many fields. And savy people know
it.
And anyone savy knows aircraft cranks have discreet marks to begin with.

Whoever the Bobby you're thinking of must be some p.o.s working in the auto
shop in Jackson.

I could care less

Kent Felkins
Tulsa

[Morgans]

"Fly" <felk AT gbronline.com> wrote

> Parts trading is well known trick in in many fields. And savy people
know
> it.
> And anyone savy knows aircraft cranks have discreet marks to begin with.
>
> Whoever the Bobby you're thinking of must be some p.o.s working in the
auto
> shop in Jackson.
>
> I could care less
>
> Kent Felkins

Obviously, you could care less, or you would not have posted a rebuttal. He
may be correct, or may be incorrect. I did notice that you did a very nice
job of turning it around to slam someone else, however.

I don't know you from a hole in the ground. I'm glad you think you work in
a good shop. You would not be working in my shop, if you did not think
where you were working was a good place. Good for you.

That said, "my" opinion of what got you "rubbed the wrong way" was your
attitude that your way was the only way, and that because you worked on
aircraft engines, no one else might be capable of doing as good a job, or
better.

Around where I live, there are racing engine shops everywhere. They feed
the racing market with engines that up and coming future stars in the auto
racing world use. While you attempt to build engines that are reliable,
they only have to be reliable at very modest power levels. The
displacements of an aircraft engine that put out 200 HP, are putting out
over 750 HP in the racing world. They do so at the expense of a long life,
but they are very reliable in that designed life span. They strive to get
just a couple more HP, or a smoother engine, or one that will have better
fuel economy to beat their competition. They innovate, and experiment, and
develop things that are incorporated into future mass produced engine
designs.

All the while, you are rebuilding 1930's engines, with precious few
innovations. I'm glad someone is doing it, and doing it well. Don't be
offended when someone else says they are capable of doing it as good, or
better. Some may be able to do just that.

To think that these engine builders don't have some tricks that you are not
interested in, or allowed to do by the FAA, or capable of performing that
results in making a smoother running engine is extremely smug of you. I
have no doubt that some may be able to do some things your shop has never
even dreamed of.

The person posting got some technical details wrong, but so what. He is not
the racing engine rebuilder. They are out there, and do quite well, thank
you. You would do well to acknowledge the fact that others do know their
craft, and have pride in it, just as you do.

Feel free to jump in and offer advise, and opinions about subjects you are
well versed in. No doubt, you have a lot to offer this group.

The most valued members come here with humility, and knowledge, but enter
into discussions with the idea that they may find someone who knows as much
or more. There is always someone out there smarter than yourself. (or
myself)

With that, is the fact that some do not know when to shut up, or when to not
flame. Those are the pitfalls of a public forum. Thick skins are required.

soapbox = off.
--
Jim (Morgan) in NC

[abripl]

OK. They managed to get things in balance - within one gram.
The only thing was the starter gear with the torsional damper. Because
of the fluid damper it changes - about 5g out max. Does anybody know if
5g is acceptable for a 10" flywheel?

[stol]

OK. They managed to get things in balance - within one gram.
The only thing was the starter gear with the torsional damper. Because
of the fluid damper it changes - about 5g out max. Does anybody know if

5g is acceptable for a 10" flywheel?



////////////////////////////////////////////

One gram is darn close for your application. You will notice a
difference when ya fire up the new beast. As for the damper, if it is a
fluid style i can tell you they never repeat while spinning up on a
balancer machine. Temp differences cause the viscious fluid to migrate
differently every time so don't sweat the small numbers there. I am
curiuos, Was this engine a first time run motor and never been into
before? You would think with all the FAA requirments they would dictate
part weights in a new "certified" motor to be closer then 5-8 grams.
I also want to say Jim was very good at reading into the fine print and
giving a great feel of what was trying to be said. I am a little
forward in expressing my views and do sometimes rub people the wrong
way and hope we can get over this feud.

Happy Hollidays all you guys.

Ben

[abripl]

> One gram is darn close for your application. You will notice a
> difference when ya fire up the new beast.

The machine shop found the biggest discrepancy in couple of rod big
ends - 10g?.

> Was this engine a first time run motor and never been into before?...

I got this engine in pieces with 1500 loged hours and rebuilt it. I
put about 85hrs on it since then. But the vib got annoying above
2400rpm. Here in SD its not ideal flying weather till Feb. so I decided
to use the time to improve the engine.
----------------------------------------------------------------
SQ2000 canard: http://www.abri.com/sq2000

[Peter Dohm]

"Morgans" > wrote in message
...
>
> "Fly" <felk AT gbronline.com> wrote
>
> > Parts trading is well known trick in in many fields. And savy people
> know
> > it.
> > And anyone savy knows aircraft cranks have discreet marks to begin
with.
> >
> > Whoever the Bobby you're thinking of must be some p.o.s working in the
> auto
> > shop in Jackson.
> >
> > I could care less
> >
> > Kent Felkins
>
> Obviously, you could care less, or you would not have posted a rebuttal.
He
> may be correct, or may be incorrect. I did notice that you did a very
nice
> job of turning it around to slam someone else, however.
>
> I don't know you from a hole in the ground. I'm glad you think you work
in
> a good shop. You would not be working in my shop, if you did not think
> where you were working was a good place. Good for you.
>
> That said, "my" opinion of what got you "rubbed the wrong way" was your
> attitude that your way was the only way, and that because you worked on
> aircraft engines, no one else might be capable of doing as good a job, or
> better.
>
> Around where I live, there are racing engine shops everywhere. They feed
> the racing market with engines that up and coming future stars in the auto
> racing world use. While you attempt to build engines that are reliable,
> they only have to be reliable at very modest power levels. The
> displacements of an aircraft engine that put out 200 HP, are putting out
> over 750 HP in the racing world. They do so at the expense of a long
life,
> but they are very reliable in that designed life span. They strive to get
> just a couple more HP, or a smoother engine, or one that will have better
> fuel economy to beat their competition. They innovate, and experiment,
and
> develop things that are incorporated into future mass produced engine
> designs.
>
> All the while, you are rebuilding 1930's engines, with precious few
> innovations. I'm glad someone is doing it, and doing it well. Don't be
> offended when someone else says they are capable of doing it as good, or
> better. Some may be able to do just that.
>
> To think that these engine builders don't have some tricks that you are
not
> interested in, or allowed to do by the FAA, or capable of performing that
> results in making a smoother running engine is extremely smug of you. I
> have no doubt that some may be able to do some things your shop has never
> even dreamed of.
>
> The person posting got some technical details wrong, but so what. He is
not
> the racing engine rebuilder. They are out there, and do quite well, thank
> you. You would do well to acknowledge the fact that others do know their
> craft, and have pride in it, just as you do.
>
> Feel free to jump in and offer advise, and opinions about subjects you are
> well versed in. No doubt, you have a lot to offer this group.
>
> The most valued members come here with humility, and knowledge, but enter
> into discussions with the idea that they may find someone who knows as
much
> or more. There is always someone out there smarter than yourself. (or
> myself)
>
> With that, is the fact that some do not know when to shut up, or when to
not
> flame. Those are the pitfalls of a public forum. Thick skins are
required.
>
> soapbox = off.
> --
> Jim (Morgan) in NC
>
Well said!
Peter