Race Engine Question

[MBrennan]

With all of the talk on other threads about race engines, I'm curious... How much of a race engine is made from "original" parts vs. new custom made parts (rods, bearings pistons,etc.)? With a finite number of "original" parts available, how do these guys keep building these incredible machines? (Aside from the obvious cubic dollars)

Good luck to all of the race teams and crews.

MJB

[tjyak50]

Re: Race Engine Question

Major assemblies like the case, cylinders, crank and cam are all original, but they cherry pick the best of the best parts and combinations.

Truth is we no longer have the capability to make those kinds of parts anymore. That is just my opinion as a round-engine owner. They had very specialized manufacturing processes back in the day.

What can be made new is valves, pistons, some cams, lifters, fingers and such. Even blowers and various gears. Plus we can use modern wires, ignition and some fuel control systems.

Lots of cool technology out there. Much of which was actually invented in the 1940s...

TJ

[eeyore]

Re: Race Engine Question

Modern CNC machining can recreate the parts for these engines. Technology hasn't been lost it's moved forward. I've heard insurnance raised but many experimental planes run non standard engines. Even car engines. Ross pistons makes custom pistons to 6.25" diameter. Custom cams, cranks etc are available it's just an issue of money and excepting Experimental flight rules

[tjyak50]

Re: Race Engine Question

Agreed.
I run Ross Pistons and Total Seal rings in the M14 of my Yak 50.
Also run SuperAlloy valves and new guides.

The parts that are harder to make are the really fancy cylinder assemblies, Master Rod assemblies, etc. Many of these are complex forgings with specialized heat treating and relieving operations.

After reading some of the Graham White books, I don't know if we can do this anymore. Certainly can't just blank it out on a Mill.

Tj

[eeyore]

Re: Race Engine Question

Actually race car connection rods are being milled out of 4130 steel billets. The art of heat treating steel has truly advanced in the modern age, nothing from the past can not be made today the issue is money. I've worked in an automotive machine shop and the cam and crank grinders were more than large enough to make Merlin parts. I used to work as a a scientific glassblower and worked at Lawerence Bezerkley. They had a vertical lathe some two stories tall with a chuck 20 feet across. A good friend was a machinist for GE electric boat division and their biggest lathe was 50 feet long. Believe me industrial ability has come a very long ways in the last 50 years even if my spelling hasn't

[BellCobraIV]

Re: Race Engine Question

Agreed.
I run Ross Pistons and Total Seal rings in the M14 of my Yak 50.
Also run SuperAlloy valves and new guides.

The parts that are harder to make are the really fancy cylinder assemblies, Master Rod assemblies, etc. Many of these are complex forgings with specialized heat treating and relieving operations.

After reading some of the Graham White books, I don't know if we can do this anymore. Certainly can't just blank it out on a Mill.

Tj

You would be amazed at what could and what has been made, having grown up in the "business" and making my living now in a specialized machine shop environement. Bottom line Money, money to counteract the liability threat, money to fund parts run instead of one here one there. Money for testing. Oh, and then there is desire as some lose desire new people have to be enticed to follow the work.

As my wife once told Tiger, The question isn't can it be done, the question is what's it gonna cost.

[ignomini]

Re: Race Engine Question

As my wife once told Tiger, The question isn't can it be done, the question is what's it gonna cost.

Amen!

[Inverted]

Re: Race Engine Question

How did the total seal rings handle in the M14p? I have had horrible luck with those things in the automotive sector.

[tjyak50]

Re: Race Engine Question

The owner of Total Seal is a friend, and their facility is at my airport.

We have had great luck with the rings.
Compressions always 80/80.
Basically no oil consumption, clean oil, no more hydraulic lock or puddles of oil on the floor. It is downright un-traditional.
Installed in a bunch of motors with lots of time on them.

What trouble did you have with them?
I have heard some people don't like their Oil Control ring setup.

Only problem is that those rings with the higher compression ratio pistons (7.3:1) caused some "run-on" problems and uncommanded starting while pulling through. The M14 has a Pressure Carb and since there is no mixture control you shut off the engine with the magnetos.

We added manual fuel shutoff valves (Hilborn) to alleviate this problem.
Nice to be EXPERIMENTAL. Surely no certified airplane has any of this stuff....

Xx

[hm66sk]

Re: Race Engine Question

I have personally seen a number of things with the Gapless rings. The original design with the second ring as the gapless ring is about the worst idea I have ever seen. To explain why I will tell you what the NASCAR boys have been doing for over a decade now to increase horse power. They have been OPENING up the gap on the second ring and have been making more power. The reason for that is if the second ring catches compression that got by the top ring it will increase in pressure until it unsettles the top ring making it flutter, therefore making the top ring useless. By opening the gap it gave the pressure that got past the top ring a way out, therefore maintaining the integrity of the top ring by letting it function as it was supposed to. I have overseen a few different street car engines (that were pretty hot) that used the gapless rings (after my opinion was asked and I said it might not be a good idea). Within about eight thousand miles it started fouling plugs and produced way too much blow by. They just would not last. The only time I saw a positive experience with them was when they were installed wrong and they put the gapless rings on top instead of in the second position. It was in a sprint car so the engine was only going to be together for about two weekends.
I know they are making gapless top ring sets, but that is what went into one of the street car engines. I prefer using a good file to fit ring package. One thing I wish was mentioned more was that the second ring is better stated as the second oil ring. Its main purpose if to catch any remaining oil that the oil rings may have missed. We have discussed this with a number of piston manufactures as well as a prominent ring manufacture so I feel the info that I have shared has some validity. The companies are Venolia Pistons, JE pistons, Wiseco Pistons and Akerly & Childs (which just happens to be the Childs from Childs and Albert). Well there you have it, that is a basic summery of some of the things I have learned over the years. I'll just leave it at that.

[tjyak50]

Re: Race Engine Question

There is a fair amount of end gap even on the "gapless" rings. About .015 to .018 if I remember correctly.

The end gap is not what makes them "gapless". It is the overlapping double "lapped-set" ring design (for those not familiar).

In my case, the owner of the company made us custom rings (Thank you Joe!). Rings are subject to preference like many things. Ask 5 engine builders which oil is best.... then stand back!

Back to the original question, these are some examples of new technology entering into very old technology engines.

Some parts are new such as rings, valves, and various components.
Some parts are original, such as cases, cranks and cams.
The learning curve for the adventurous can be wicked.

[440_Magnum]

Re: Race Engine Question

Modern CNC machining can recreate the parts for these engines. Technology hasn't been lost it's moved forward.

For the most part, I agree. However, can you find a CNC-equipped shop that could actually produce an R-3350 cylinder with the equivalent of the original Wright cooling fin design? Or the ultra-fine fins on an R-4360 jug? That's actually a pretty tall order, not just in that it would take a ton of money, but also just to DO it correctly without the specialized tooling that the original builders developed specifically for cutting those cooling fins.

[ignomini]

Re: Race Engine Question

Okay, dumb car guy question time. Can you re-sleeve an aircraft cylinder? I'm assuming they have steel liners in them. I sell sleeves for auto engines every day. I guess I should know these things.

[hm66sk]

Re: Race Engine Question

There is a fair amount of end gap even on the "gapless" rings. About .015 to .018 if I remember correctly.

The end gap is not what makes them "gapless". It is the overlapping double "lapped-set" ring design (for those not familiar).

In my case, the owner of the company made us custom rings (Thank you Joe!). Rings are subject to preference like many things. Ask 5 engine builders which oil is best.... then stand back!

Back to the original question, these are some examples of new technology entering into very old technology engines.

Some parts are new such as rings, valves, and various components.
Some parts are original, such as cases, cranks and cams.
The learning curve for the adventurous can be wicked.

Sorry for the rant. It was late and I was upset about the tragic loss at Stead.

[oakfloor]

Re: Race Engine Question

I have also thought about this, would it be possible to drop forge a merlin crankshaft or camshafts? and what about the prop reduction gears. What parts are wearing out that cannot be reproduced? I think they have to be getting down to a very few left.