#21 Stetina Lightened flywheel

[jdoclogan]

Having a community of Sunbeam enthusiasts, with a strong communication linkage through SAOCA, is an amazing benefit. My recent acquisition of a race prepared alpine engine via this site has proven to be a gain for putting together the Roy Stetina #21 1960s racing Alpine. As the engine came in a rather tired and mistreated body it seemed logical to do a test run and determine if it would be appropriate for the Stetina Alpine. With a bit of battery assistance the engine fired up with its twin Delloroto carbs breathing loud. A quick run and I could feel somewhere around 110 hp. Do a compression check and find 180 +/- 5psi. Remove the intake/exhaust manifold and see intake port and polish work has been done on the head. Pulled the engine via the drop front cross-member technique. (https://www.icloud.com/attachment/?...kekA5_nDKEBe9EkmJg&f=IMG_4333.MOV&sz=35220864).

Attach engine to stand and begin further examination and begin detailing. By doing a bore scope investigation I find prominent cross hatching still present, the fitting of flat top pistons, and larger than stock valves.
Upon removing the transmission I find an unusual lightened flywheel. Michael King thought it looked similar to "an oversized timing chain gear." I'm not going to remove the assembly in order to weigh the flywheel as everything may already be balanced and dialed in. However, I'm guessing it has to be well under the stock 20+ lbs.
Also, there is an oil "water cooler" assembly.

 

[Bill Blue]

Wowzer! Can't quite wrap my head around this flywheel. Just where is the flywheel clutch surface and how is it supported?
Bill

 

[jdoclogan]

Bill,

Look closer on the right flywheel photo. You can see two prongs (there are four total prongs) attached to the flywheel starter ring component. They connect to a center disk (clutch surface) that the clutch will engage with.

 

[Barry]

Having a community of Sunbeam enthusiasts, with a strong communication linkage through SAOCA, is an amazing benefit. My recent acquisition of a race prepared alpine engine via this site has proven to be a gain for putting together the Roy Stetina #21 1960s racing Alpine. As the engine came in a rather tired and mistreated body it seemed logical to do a test run and determine if it would be appropriate for the Stetina Alpine. With a bit of battery assistance the engine fired up with its twin Delloroto carbs breathing loud. A quick run and I could feel somewhere around 110 hp. Do a compression check and find 180 +/- 5psi. Remove the intake/exhaust manifold and see intake port and polish work has been done on the head. Pulled the engine via the drop front cross-member technique. (https://www.icloud.com/attachment/?u=https://cvws.icloud-content.com/B/AYQJxB1jIe2SAjzdVQQ7CcYbcaPMAYnYpTc1f8QdqJid-nT0JDWTufat/${f}?o=AtyP1ePpFDgExt_xZayyunl3l98nTFW8jhdYz347olIh&v=1&x=3&a=CAogbwfxfwaff4JwpWwzl9AUhLeSmJbDPOFslYsbc1901Z8SdhCWiu-r5jAYlprq_-8wIgEAKgkC6AMA_21v-apSBBtxo8xaBJO59q1qJcaahiwSLiGGJR5fPhrHTbzRm3_uLF1FdzxAxzhMy946xxBJ-C1yJTLhZjqIMc-fP-_odPrtt_ks8OAOtFDoYkE5dNwVhf9CC6mO-o8&e=1679331855&fl=&r=2E5E4433-CAF2-4BED-9911-6E48DDC8AC38-1&k=${uk}&ckc=com.apple.largeattachment&ckz=49454973-7ED5-4EA3-9C8C-2A66F5E80C91&p=29&s=gaquDrXfF8GSBdI8J3UbjMyNCVE&uk=A_a6kekA5_nDKEBe9EkmJg&f=IMG_4333.MOV&sz=35220864).

Attach engine to stand and begin further examination and begin detailing. By doing a bore scope investigation I find prominent cross hatching still present, the fitting of flat top pistons, and larger than stock valves.
Upon removing the transmission I find an unusual lightened flywheel. View attachment 28126View attachment 28127 Michael King thought it looked similar to "an oversized timing chain gear." I'm not going to remove the assembly in order to weigh the flywheel as everything may already be balanced and dialed in. However, I'm guessing it has to be well under the stock 20+ lbs.
Also, there is an oil "water cooler" assembly. View attachment 28128

"Unusual" is a major understatement for that flywheel setup!

The oil-to-water heat exchanger in the last picture looks like a Ford part number F85Z-6A642-AB which was used on F-150 pickups from 1997-2004. Oil-to-water heat exchangers get the oil warm quickly and then keep the oil temp in a very narrow range.

​

 

[DanR]

Doc, I sure hope if you intend running that "flywheel" you will build a very strong scatter shield that can definitely deflect the pieces that will come off. Can't believe the PO ran that at high RPMs at extended times.....

I had a flywheel come loose and tore through the floor around the tranny tunnel, the dash and part of the windshield out of my '62 Vette in 1964 at the Walterboro Drag Strip. I was peppered with South Carolina sand from the floor, my right foot was lifted rather rapidly up a ways but no other damage to me. The Vette was a mess.

The scatter shield probably save me from serious injury.

 

[spmdr]

Yes, "scatter-sheilds" were required by the SCCA.

I removed a rather unattractive mass of Steel around the bellhousing area of the Trans tunnel,

On the Weekend Racer S2 Alpine.

BTW, the first time I saw the Oil to water cooler was on the CHP Mustangs, of the '80s.

DW

 

[alpine_64]

@RootesRacer came up with a water to oil cooler mod for alpines back in the early 2000s iirc....
I think our President may have used one,?

 

[alpine_64]

@jdoclogan

Jerry what year did the car race until? I was undef the impression it stopped in the early 70s, the oil cooler mod is a much later mod . Was it on the car or you added it?

 

[Tom13]

Bill,

Look closer on the right flywheel photo. You can see two prongs (there are four total prongs) attached to the flywheel starter ring component. They connect to a center disk (clutch surface) that the clutch will engage with.

....the mounting and the coupling surface are certainly designed as shown here in the pictures. This flywheel is with 5.7 kg a lot lighter than the original flywheel. It was made to use a Toypta clutch on a 5 speed Toyota transmission. The matching bellhousing came from Dellow Automotis in Australia.

 

[DanR]

The Designer's idea was great but even better at producing the end result.

I am going to show this to my Drafttsman/Engineer Buddy, He will be impressed for sure.

 

[Alpine 1789]

@RootesRacer came up with a water to oil cooler mod for alpines back in the early 2000s iirc....
I think our President may have used one,?

Good memory, Michael. I bought one from a Merkur when I first heard about the conversion and put it in about 12 years ago. I have no idea if it was worth the effort, but I like the fact that I can change all of the oil and not leave the old cooler and hose oil in the system. Merkur coolers are probably unobtanium by now, so it is good to know that other coolers would work.

 

[jdoclogan]

@jdoclogan

Jerry what year did the car race until? I was undef the impression it stopped in the early 70s, the oil cooler mod is a much later mod . Was it on the car or you added it?

The engine did not come with the Roy Stetina race car (raced from 62-68). The engine is from the Todd Norby Alpine I bought last Fall.

 

[jdoclogan]

....the mounting and the coupling surface are certainly designed as shown here in the pictures. This flywheel is with 5.7 kg a lot lighter than the original flywheel. It was made to use a Toypta clutch on a 5 speed Toyota transmission. The matching bellhousing came from Dellow Automotis in Australia.

Tom, I appreciate your input concerning the flywheels weight. Weight of theTVR Racing Lightened flywheel I have obtained is:
Weight - 4.35 kg = 8.59lbs
Clutch - 215mm = 8.46 inches

 

[jdoclogan]

Doc, I sure hope if you intend running that "flywheel" you will build a very strong scatter shield that can definitely deflect the pieces that will come off. Can't believe the PO ran that at high RPMs at extended times.....

I had a flywheel come loose and tore through the floor around the tranny tunnel, the dash and part of the windshield out of my '62 Vette in 1964 at the Walterboro Drag Strip. I was peppered with South Carolina sand from the floor, my right foot was lifted rather rapidly up a ways but no other damage to me. The Vette was a mess.

The scatter shield probably save me from serious injury.

Dan, thanks for thoughts about my well fare. However, I'm thinking that the 110HP +/- 5HP probably won't put enough stress on the flywheel to be of any concern. And then he says, " YOW!!, $%%#, I should have listened to Dan."

 

[Tom13]

Tom, I appreciate your input concerning the flywheels weight. Weight of theTVR Racing Lightened flywheel I have obtained is:
Weight - 4.35 kg = 8.59lbs
Clutch - 215mm = 8.46 inches

I wasn't sure of the weight of the flywheel and went to the garage to reweigh. Without starter ring
gear I come to 4.3 kg plus about 1 kg for the gear.

I still planned for safety in the design. I would without hesitation the flywheel ( C45 Steel ) at some
points still facilitate.

The Flywheel is designed for 200 mm clutch plate.

 

[Barry]

Doc, I sure hope if you intend running that "flywheel" you will build a very strong scatter shield that can definitely deflect the pieces that will come off. Can't believe the PO ran that at high RPMs at extended times.....

I had a flywheel come loose and tore through the floor around the tranny tunnel, the dash and part of the windshield out of my '62 Vette in 1964 at the Walterboro Drag Strip. I was peppered with South Carolina sand from the floor, my right foot was lifted rather rapidly up a ways but no other damage to me. The Vette was a mess.

The scatter shield probably save me from serious injury.

I was in the front passenger seat when the driver of a 1964 Ford Galaxy with a HiPo 289 missed a "power shift" and the engine RPM went to the moon. The clutch cover came apart and half of the pressure plate went through the top of the factory bellhousing and then through the back of the hood. If it had gone to the right instead of up, I would probably have lost a foot. Made me a believer in scatter shields.

 

[DanR]

Barry, Can you imagine "if it had stayed in the car and not had the shield to deflect it?

I gave the '62 experience a lot of thought..........and a few years later '67 was my last time doing really wild stuff.

That is when Viet Nam called and change my life for good/better.

 

[spmdr]

I'm still in the market for a few Light Flywheels.

But the "Stetina" version/style does not get me excited.

I think the open areas cause more undesirable windage.


And I sure hope no one makes the open style version out of an

original iron flywheel!

DW

 

[alpine_64]

And I sure hope no one makes the open style version out of an

original iron flywheel!

DW

Quite sure that's what the Stentina one is... Jerry will be wrapping the bellhousing with MUCH Kevlar...I hope

 

[husky drvr]

The engine did not come with the Roy Stetina race car (raced from 62-68). The engine is from the Todd Norby Alpine I bought last Fall.

Jerry,

I finally found where I recall that flywheel from the past. I remembered the member's name but not his screen name. Apparently the discussions about the machining of the flywheel were lost with "The Great Lost Forum Database." Looking through his comments remaining in the current forum, I did note one comment stating he still had some receipts for a Todd. It's probably the same white Alpine.

At least the member's avatar is a picture of the said flywheel. IIRC, he had access to borrow CNC equipment and not a lot of machining experience. He stated he was trying for max lightening and went much farther than the sII racing guide recommendations. Commented also that the holes were a mistake, but cool. He then sold the car due to life and other interests without ever really driving the car.

Hope this helps,

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