Author Topic: Fox .35 Hemi-Head (Read 8037 times)

George Albo · « **on:** July 08, 2015, 09:35:15 AM »

Can someone post a picture of the inside of the Fox .35 Hemi-Head? Better yet, does anyone have anything that resembles a shop drawing?
Thanks

Bill Little · « **Reply #1 on:** July 08, 2015, 03:39:32 PM »

Quote from: George Albo on July 08, 2015, 09:35:15 AM

Can someone post a picture of the inside of the Fox .35 Hemi-Head? Better yet, does anyone have anything that resembles a shop drawing?
Thanks

Hi George,

Not being picky, but are you talking about the factory head button and clamp? It is a two piece item. There are at least two others, one by Randy Smith and another by Larry Foster (for sale through RSM). They are one piece designs.

Bill

George Albo · « **Reply #2 on:** July 08, 2015, 05:57:22 PM »

Not the two piece that Fox sold. there was this Hemi Head called Blue Magic out of California. I really wanted to look at it more than anything to see what the big deal was/is with this. What it looks like etc

I've been out of the hobby for a long time and getting back I've found a lot of new stuff. I called Randy about a balanced crankshaft, but haven't decided yet on it. Dukes .35 were pretty good out of the box as far as I remember them. Doing research on this.

Thanks for answering

George Albo

Wayne J. Buran · « **Reply #3 on:** July 08, 2015, 07:09:17 PM »

The blue hemi head was made by a fellow who's last name was Mugleston I believe. Hasn't been made for a number of years. There weren't that many made anyhow.
Wayne

Ron Cribbs · « **Reply #4 on:** July 08, 2015, 07:35:43 PM »

I have a Lew Woolard .35 that has a Blue Magic head, Give me a day top pop the head off and I'll post a picture for you.

Ron

De Hill · « **Reply #5 on:** July 08, 2015, 07:42:52 PM »

Marvin Denny made a Hemi Head. He told me that it was imitated (poorly) by John Lowry from Fox.

Brett Buck · « **Reply #6 on:** July 08, 2015, 07:57:25 PM »

Quote from: Wayne J. Buran on July 08, 2015, 07:09:17 PM

The blue hemi head was made by a fellow who's last name was Mugleston I believe. Hasn't been made for a number of years. There weren't that many made anyhow.
Wayne

Tom Muggleton, as I recall. I may have one around here somewhere.

Brett

Randy Cuberly · « **Reply #7 on:** July 08, 2015, 08:02:00 PM »

Quote from: George Albo on July 08, 2015, 05:57:22 PM

Not the two piece that Fox sold. there was this Hemi Head called Blue Magic out of California. I really wanted to look at it more than anything to see what the big deal was/is with this. What it looks like etc

I've been out of the hobby for a long time and getting back I've found a lot of new stuff. I called Randy about a balanced crankshaft, but haven't decided yet on it. Dukes .35 were pretty good out of the box as far as I remember them. Doing research on this.

Thanks for answering

George Albo

In their day the Fox 35 was a reasonably good engine. However most of the ones used in serious competition were heavily modified with after market parts. A Fox 35 like this is (I think), still available from Eric Rule at RSM. They were specially tuned by Larry Foster and work pretty well. The photo below shows a couple of the Larry Foster Foxes configured for a twin...one has a left hand crank! They contain special parts and special fitting but not the Hi Zoot balanced crank that Randy Smith makes.

Today there are much better options available. In fact most of the available .25 size engines will produce more power and a more consistent run. Most of them are made as R/C engines and do require the installation of a venturi and needle valve assembly of the Super Tigre or Aero Products (Randy Smith) type. The Hi Zoot full boat Fox 35 that Randy Smith sells has very little in common with the old Fox 35. For starters it has a different crank that doesn't vibrate, a different head and other parts that make it a much more powerful and consistent running engine. The draw back is that it is fairly expensive!

The OS LA25R/C can be converted to a C/L engine quite easily with only the aforementioned venturi and needle valve assembly. Those are available from Aero Products or RSM or a plethora of others.

The typical stock Fox 35 can be a reasonable "Sport" engine though most still change the needle valve assembly. However if mounted in a profile configuration most disply the "dreaded Fox Burp", a condition where the engine momentarily quits and restarts on hard outside maneuvers. It can be fixed by partially blocking the intake port in the sleeve but it does require some engine expertise.

All in all the newer engines are more reliable and longer lasting and overall eaiser to deal with.

If you are in fact a real Fox afficianado and want to use one then by all means deal with Randy Smith or Eric at RSM.

If you intend to fly in competition you will eventually want something larger or maybe even Electric, which is the latest buzz for competition experts etc.

Randy Cuberly

George Albo · « **Reply #8 on:** July 08, 2015, 08:57:40 PM »

Quote from: Ron Cribbs on July 08, 2015, 07:35:43 PM

I have a Lew Woolard .35 that has a Blue Magic head, Give me a day top pop the head off and I'll post a picture for you.

Ron

I'll be looking forward to seeing this up close and personal. When you do, penny next to it for scale?
Thank you!

George Albo

George Albo · « **Reply #9 on:** July 08, 2015, 09:05:08 PM »

Quote from: Randy Cuberly on July 08, 2015, 08:02:00 PM

In their day the Fox 35 was a reasonably good engine. However most of the ones used in serious competition were heavily modified with after market parts. A Fox 35 like this is (I think), still available from Eric Rule at RSM. They were specially tuned by Larry Foster and work pretty well. The photo below shows a couple of the Larry Foster Foxes configured for a twin...one has a left hand crank! They contain special parts and special fitting but not the Hi Zoot balanced crank that Randy Smith makes.

Today there are much better options available. In fact most of the available .25 size engines will produce more power and a more consistent run. Most of them are made as R/C engines and do require the installation of a venturi and needle valve assembly of the Super Tigre or Aero Products (Randy Smith) type. The Hi Zoot full boat Fox 35 that Randy Smith sells has very little in common with the old Fox 35. For starters it has a different crank that doesn't vibrate, a different head and other parts that make it a much more powerful and consistent running engine. The draw back is that it is fairly expensive!

The OS LA25R/C can be converted to a C/L engine quite easily with only the aforementioned venturi and needle valve assembly. Those are available from Aero Products or RSM or a plethora of others.

The typical stock Fox 35 can be a reasonable "Sport" engine though most still change the needle valve assembly. However if mounted in a profile configuration most disply the "dreaded Fox Burp", a condition where the engine momentarily quits and restarts on hard outside maneuvers. It can be fixed by partially blocking the intake port in the sleeve but it does require some engine expertise.

All in all the newer engines are more reliable and longer lasting and overall eaiser to deal with.

If you are in fact a real Fox afficianado and want to use one then by all means deal with Randy Smith or Eric at RSM.

If you intend to fly in competition you will eventually want something larger or maybe even Electric, which is the latest buzz for competition experts etc.

Randy Cuberly

Randy, thank you for taking the time to give over so much info. The Fox, O.S. Max, and Enya .35's are pretty much what I know. Thanks for the suggestions on the .25. I have a number of projects I want to undertake for sport and fun, but I also want to start working on the pattern and learning it, time permitting.

Thanks again,
George Albo

George Albo

George Albo · « **Reply #10 on:** July 08, 2015, 09:11:29 PM »

Thanks everyone for taking the time to answer me and to those of you that are going to take pics for me. Can't thank you enough.
George Albo

Ron Cribbs · « **Reply #11 on:** July 08, 2015, 10:24:27 PM »

George,

PM me your email, I can't shrink my photo's enough to post here.

Edit: well shoot! It posted tell me if that is good enough.

Geoff Goodworth · « **Reply #12 on:** July 08, 2015, 11:19:26 PM »

It doesn't really answer George's question but converting the RC versions of FP/LA 25s can be done with just two readily available factory parts.

FP 20/25 Venturi Tower Part No LXCW99 $9.49 OS Part No 22312000
NVA 20-25FP-S Tower Part No LXCR49 $13.49 OS Part No 22311000

The price is from a few months ago when I last checked. It may have changed.

Brett Buck · « **Reply #13 on:** July 09, 2015, 12:03:39 AM »

Quote from: George Albo on July 08, 2015, 05:57:22 PM

Not the two piece that Fox sold. there was this Hemi Head called Blue Magic out of California. I really wanted to look at it more than anything to see what the big deal was/is with this. What it looks like etc

I've been out of the hobby for a long time and getting back I've found a lot of new stuff. I called Randy about a balanced crankshaft, but haven't decided yet on it. Dukes .35 were pretty good out of the box as far as I remember them. Doing research on this.

Almost none of the Fox modifications are intended to significantly increase the performance for stunt, if that's what you mean. Most are for durability or reliability - stuffer backplate, "trick" crankshaft, ST or other replacement NVA, ABC piston and liner, etc. The hemi-heads *sometimes* cause the 4-stroke to be maintained to a higher RPM, but it's a fairly subtle effect and it may be achievable with other compression changes. Don't expect a big jump in power from any of these, the basic design of the engine is limiting.

There's a post by Marvin Denny (who may have been the first one to try it) explaining the changes with the hemi-head, and it's much more of a "tweak" to change the way it runs slightly, but not to get a lot more power overall.

Significant improvements in the performance are more easily done with fuel - more oil and more nitro, up to 15% with the stock crank, and maybe even 25% with a trick crankshaft (that will not break at the higher nitro contents).

Brett

Dennis Moritz · « **Reply #14 on:** July 09, 2015, 06:00:43 AM »

Piston fit and crankshaft fit offer most advantage. Hi zoot crank doesn't break. Big plus. Far as improvement in vibration. We haven't noticed much. Philly Flyers use Fox 35s a lot. The expensive mods and parts are used here and there, most Foxes are run without them. Dan Banjok's Fox 35s have used stuffer back plates, used stock back plates, hemi heads and stock heads, hi zoot and no-zoot cranks. On any given fly day at our field might be 5 or 6 of these running. Dan has won and placed high in Old Time and Classic in contests many times using Fox 35s. At the last Brodak he won Classic flying a Galloping Comedian powered by a Fox 35. The Comedian is an Old Time bird, no flaps. Same bird and Fox 35 have finished in 2nd or 3rd at the NATS in Classic. No one in our club stuffs a Popsicle stick in the port. The dreaded burp doesn't disturb our sleep. Not much of an issue. Depends on how the engine is run. On the other hand the thin liner and casting will easily distort. Lots of our Foxes are run on Ringmasters. A profile last time I looked. The winningest Ringmaster of all time used a Fox 35. Lots of chuckles when it won major Old Time Contests. A few Ringmasters in our club powered by Fox 35s have even won local Classic events.

Dennis Moritz · « **Reply #15 on:** July 09, 2015, 06:06:45 AM »

Stuffing ports is a ritual return topic on these threads. Regular as the seasons. Or Halloween. Boo. Scared yet. In Philly we also don't stuff ports in FP40s and Tower 40s. We get them to work quite well without hocus pocus.

Larry Fernandez · « **Reply #16 on:** July 09, 2015, 01:33:40 PM »

Quote from: Dennis Moritz on July 09, 2015, 06:06:45 AM

Stuffing ports is a ritual return topic on these threads. Regular as the seasons. Or Halloween. Boo. Scared yet. In Philly we also don't stuff ports in FP40s and Tower 40s. We get them to work quite well without hocus pocus.

WOW!!! You guys in Philly are truly the gods of stunt. I will bow to the east every Sunday morning before I make my first flight.

Larry, Buttafucco, Stunt Team

Phil Spillman · « **Reply #17 on:** July 09, 2015, 01:56:55 PM »

I have enjoyed the improvements made by adding the Magic Blue head to several of my Foxes over the years. In addition to the head I like the change afforded by adding an ST NVA to the engine without drilling out the venturi. On occasion the stiffer back plate will also improve the stunt run of the .35. Of utmost importance is to use an adequate amount of oil in the fuel. 25% is usually enough for my purposes and the use of a 50:50 mix, contrary to popular belief will work just fine! At least it has for me!!!

Phil Spillman

Motorman · « **Reply #18 on:** July 09, 2015, 04:07:57 PM »

That's right, I said Hemi. (Joe Dirt)

MM

Dennis Moritz · « **Reply #19 on:** July 09, 2015, 04:36:54 PM »

Larry. Guess you enjoy Foxes and know all about them. I describe what we do. It works pretty well. I thought the self congratulation trophy was on permanent exhibition elsewhere. Interesting how folks who dislike Foxes offer endless opinions about what they need to run right.

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George Albo · « **Reply #20 on:** July 09, 2015, 04:58:48 PM »

Quote from: Ron Cribbs on July 08, 2015, 10:24:27 PM

George,

PM me your email, I can't shrink my photo's enough to post here.

Edit: well shoot! It posted tell me if that is good enough.

Ron that's a great picture. Thank you very much!!
George Albo

Quote from: Phil Spillman on July 09, 2015, 01:56:55 PM

I have enjoyed the improvements made by adding the Magic Blue head to several of my Foxes over the years. In addition to the head I like the change afforded by adding an ST NVA to the engine without drilling out the venturi. On occasion the stiffer back plate will also improve the stunt run of the .35. Of utmost importance is to use an adequate amount of oil in the fuel. 25% is usually enough for my purposes and the use of a 50:50 mix, contrary to popular belief will work just fine! At least it has for me!!!

Phil Spillman

Phil what type and brand of oil are you using with the caster?

Larry Fernandez · « **Reply #21 on:** July 09, 2015, 05:10:29 PM »

[ Interesting how folks who dislike Foxes offer endless opinions about what they need to run right.

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[/quote]

I don't ever recall saying that I disliked Fox .35's
In fact, if they are properly broken in, run with the right fuel and right prop installed inverted or upright in a Nobler sized plane they can be awesome motors. The Fox .15 on the other hand...............

Larry, Buttafucco Stunt Team

De Hill · « **Reply #22 on:** July 09, 2015, 05:24:35 PM »

You don't seem to know much about Fox .15's either, Larry. A whole lot of people run them with no problem.

Larry Fernandez · « **Reply #23 on:** July 09, 2015, 05:32:26 PM »

Quote from: De Hill on July 09, 2015, 05:24:35 PM

You don't seem to know much about Fox .15's either.

What I do know is that I can "Hurl" one 239 feet. (An Unofficial World Record)

Larry, Buttafucco Stunt Team

De Hill · « **Reply #24 on:** July 09, 2015, 05:34:26 PM »

It's amusing to see someone start an event to celebrate his incompetence in running an engine. (when others do it with no problem)

Dennis Moritz · « **Reply #25 on:** July 09, 2015, 05:57:45 PM »

What's your problem Larry? Sounds like you agree with our approach.

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Ron Cribbs · « **Reply #26 on:** July 09, 2015, 08:02:49 PM »

George,

If available to you I would recommend GMA 10/22 or 5/22.

It's made by Powermaster, now known as VP racing fuels. 50/50 Castor/Synth

I have also seen folks take GMA 10/29 and cut it with 10/22. You end up with around 24-25% oil. It works ok too, but personally I stick with 10/22 as it makes for a cleaner break in my experience.

The 10/22 was recommended to me by a Philly flyer and I have used it for 100's of flights without issue. Even on screaming lean runs.

Ron

Dennis Moritz · « **Reply #27 on:** July 09, 2015, 09:16:15 PM »

I think Larry is being funny. Last long thread made it hard for me to tell. Never figured out the tone. "Buttafucco" very funny. Maybe Larry isn't being funny.

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George Albo · « **Reply #28 on:** July 09, 2015, 10:40:58 PM »

Quote from: Ron Cribbs on July 09, 2015, 08:02:49 PM

George,

If available to you I would recommend GMA 10/22 or 5/22.

It's made by Powermaster, now known as VP racing fuels. 50/50 Castor/Synth

I have also seen folks take GMA 10/29 and cut it with 10/22. You end up with around 24-25% oil. It works ok too, but personally I stick with 10/22 as it makes for a cleaner break in my experience.

The 10/22 was recommended to me by a Philly flyer and I have used it for 100's of flights without issue. Even on screaming lean runs.

Ron

Thank you.
George Albo

George Albo · « **Reply #29 on:** July 09, 2015, 10:42:32 PM »

Quote from: Dennis Moritz on July 09, 2015, 06:00:43 AM

Piston fit and crankshaft fit offer most advantage. Hi zoot crank doesn't break. Big plus. Far as improvement in vibration. We haven't noticed much. Philly Flyers use Fox 35s a lot. The expensive mods and parts are used here and there, most Foxes are run without them. Dan Banjok's Fox 35s have used stuffer back plates, used stock back plates, hemi heads and stock heads, hi zoot and no-zoot cranks. On any given fly day at our field might be 5 or 6 of these running. Dan has won and placed high in Old Time and Classic in contests many times using Fox 35s. At the last Brodak he won Classic flying a Galloping Comedian powered by a Fox 35. The Comedian is an Old Time bird, no flaps. Same bird and Fox 35 have finished in 2nd or 3rd at the NATS in Classic. No one in our club stuffs a Popsicle stick in the port. The dreaded burp doesn't disturb our sleep. Not much of an issue. Depends on how the engine is run. On the other hand the thin liner and casting will easily distort. Lots of our Foxes are run on Ringmasters. A profile last time I looked. The winningest Ringmaster of all time used a Fox 35. Lots of chuckles when it won major Old Time Contests. A few Ringmasters in our club powered by Fox 35s have even won local Classic events.

Thank you Dennis,
George Albo

George Albo · « **Reply #30 on:** July 09, 2015, 10:47:13 PM »

Quote from: Geoff Goodworth on July 08, 2015, 11:19:26 PM

It doesn't really answer George's question but converting the RC versions of FP/LA 25s can be done with just two readily available factory parts.

FP 20/25 Venturi Tower Part No LXCW99 $9.49 OS Part No 22312000
NVA 20-25FP-S Tower Part No LXCR49 $13.49 OS Part No 22311000

The price is from a few months ago when I last checked. It may have changed.

Geoff thanks for the info. Seems that O.S. has discontinued production of the .25 LA

Dennis Moritz · « **Reply #31 on:** July 10, 2015, 12:52:05 AM »

At the moment there are no inexpensive dedicated CL engines manufactured. Suitable conversions of currently manufactured RC engines will probably surface. Go to swaps, if you find one in traveling distance. Folks usually sell stuff cheap at local contests. Another source. Where do you live? Always best to find a club.

George Albo · « **Reply #32 on:** July 11, 2015, 11:20:38 PM »

I've been online buying Fox, Enya, and O.S. .35's on ebay. I also got a couple of Aviastar .46. Very nice engines. Too bad the owners decided it was retirement time and stopped making these. Thanks for the input.

George Albo