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SDS No More Leak Induction Tube Solution

rv6ejguy

Well Known Member
We've been working on this design from a concept submitted by Michael Robinson (Toobuilder) for some time now. With machine shop time being constantly tasked to supply normal parts for our EFI kits, it seemed to take forever to get these prototyped, tweaked and tested. We finally have production parts available.



These use a COTS silicone O-ring to seal the tube flange against the head, eliminating the flat gaskets which have been known to leak and cause grief on occasion.

Like our SDS valve covers, these billet flanges tighten down flat with even, metal to metal contact so there is no more flange distortion or "give" in the gasket over time.

They will come as a kit which also includes the O-rings, silicone hoses and constant tension clamps to replace the factory parts. For carbed engines, we'll supply new standard rubber hoses and Viton O-rings. Will be available for both 1.5 and 1.75 OD induction tubes, in gold or red anodized finish.

I'll try to get a photo of the complete kit this weekend.
 
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After trying several different gaskets including paper, composition, silicone and even dead soft copper, I threw a rough O ring idea at Ross and sure enough, he took it and improved it. Some prototype parts showed up in my mailbox and I promptly installed them on the -8. Keep in mind the -8 is an angle valve, requiring the added step of cutting and re welding the tubes to replace the flange clamps. Easy, but not required on the parallel valve engines.

Anyway, once the new clamps are on the tube, you simply install the O ring over the inner retainer and slip the assembly in place between the head and clamp. Snug up the bolts to spec and you are done. Unlike with the paper gaskets, it is impossible to bow the retainer or over compress the O ring. It's simply a install and forget thing.

There have been many attempts to "fix" the induction leaks at the head over the decades since the Lycoming was designed - this is finally the one that works.

2hds1tf.jpg
 
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Here's what the whole kit looks like for a 4 cyl. (will have 8 clamps of course)



For injected engines, the price is $60US per cylinder.

Carbed engines are a bit more as we have to supply a standard hose which is more expensive than the silicone ones.

Thanks to Mike again for his good idea and for offering to test these for us.
 
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The latest parallel valve engines (M1B) is made like your angle valve description and would need the tube cut/welded. Then, it has a formed flange for a fat o-ring fitting into the intake manifold/oil pan.

Kudos!! So let me understand, the intake tube flange will sit hard on the new flange on the bottom, then the o-ring seals between the top of that flange and the head, with the addition loose ring providing a hard clamping on the top side between the flange and head? This will result in the top end hard clamped with the ring insert, sealed with the o-ring, and floating (head motion) on the intake end of the tube?

In rewelding the tubes, do they need to be tacked in situ to ensure they are aligned and flat against the head?
 
Perhaps you should offer a flange only kit for people with cold induction. They won't need the sleeves & clamps.
 
This is a great idea, but I'm not visualizing how it would all fit together on my carbureted O-290-D2. My intake tubes have flanges on the ends. So the new billet pieces (not sure what you call them) would slide onto the tubes and the flange on the end of the intake tube would seat metal-to-metal into the billet piece? Is that right? Then the O-ring would be inserted on top of the intake tube flange, and that shiny metal ring (not sure what you call that, either) would also fit on the intake flange inside the O-ring? Is the purpose of the metal ring to keep the O-ring spread? Also, I don't understand why would I need new hoses and hose clamps?
 
The latest parallel valve engines (M1B) is made like your angle valve description and would need the tube cut/welded. Then, it has a formed flange for a fat o-ring fitting into the intake manifold/oil pan.

Kudos!! So let me understand, the intake tube flange will sit hard on the new flange on the bottom, then the o-ring seals between the top of that flange and the head, with the addition loose ring providing a hard clamping on the top side between the flange and head? This will result in the top end hard clamped with the ring insert, sealed with the o-ring, and floating (head motion) on the intake end of the tube?

In rewelding the tubes, do they need to be tacked in situ to ensure they are aligned and flat against the head?

There are various iterations of induction tube layouts. If you have a type that the OEM flange won't slide off freely, you'll have to cut the tube, install flange and re-weld the tube. Most older parallel valve engines, just slide the flange over the tube. Mike can probably tell you the best place to cut the AV type tube.

The O-ring sits against the tube flange, the tube flange contacts the CNC'd flange metal to metal, just as the stock parts do. The silver ring inside the O-ring contains the O-ring in its cavity when it's compressed to provide the proper degree of squish.

You can rotate the tube with some force when the bolts are tightened down.
 
We offer the new hoses and constant tension clamps for those who want new stuff there. The CT clamps never need tightening. Mike has tested those as well and they are a better solution than the old style stuff. The idea is to eliminate all maintenance in this area.

We'll sell just the flanges, O-rings and support rings to those who don't want or need the hoses and clamps. Be a bit less money.

Bad news at this time, this whole first batch is spoken for from people who have sent PMs and messages here. I'll put another batch on the machining list on Monday and try to fast track them through that and the anodizing process.

We appreciate the support!
 
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ECI jugs/heads....Superior cold air induction

Ross,

I just had parallel valve 360 build using ECI jugs/heads along with a Superior cold air induction. Mine is a little bit of a hybrid but I?m sure the intake tubes that I have were part of the Superior cold air induction kit. Barrett built my engine but it actually hadn?t been shipped to me yet...(I?ll be getting it in about two weeks), so I actually haven?t laid eyes on it yet so I?m not able to verify exactly what I have as we speak. So, with the question being raised regarding the different type of flanges, what kind do you suspect I have? Do you think your kit will work as-is on my application or do you think it?ll need to be modified? My intake tubes have already been powder coated so hopefully no cutting or welding will be required to be able to use your new setup. Thanks!

Mark
 
T So let me understand, the intake tube flange will sit hard on the new flange on the bottom, then the o-ring seals between the top of that flange and the head, with the addition loose ring providing a hard clamping on the top side between the flange and head? This will result in the top end hard clamped with the ring insert, sealed with the o-ring, and floating (head motion) on the intake end of the tube?

The silver ring inside the O-ring contains the O-ring in its cavity when it's compressed to provide the proper degree of squish.

This is standard stuff for "O" rings, otherwise it could be possible to over compress the "O" ring, and squeeze it out of position thus loosing the seal.
 
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Ross,

I just had parallel valve 360 build using ECI jugs/heads along with a Superior cold air induction. Mine is a little bit of a hybrid but I?m sure the intake tubes that I have were part of the Superior cold air induction kit. Barrett built my engine but it actually hadn?t been shipped to me yet...(I?ll be getting it in about two weeks), so I actually haven?t laid eyes on it yet so I?m not able to verify exactly what I have as we speak. So, with the question being raised regarding the different type of flanges, what kind do you suspect I have? Do you think your kit will work as-is on my application or do you think it?ll need to be modified? My intake tubes have already been powder coated so hopefully no cutting or welding will be required to be able to use your new setup. Thanks!

Mark

I haven't seen all the aftermarket tubes available. Our flanges have an ID of 1.800 so if your tube OD is less than that where the bead is, these will slip over with no cutting.
 
There are various iterations of induction tube layouts. If you have a type that the OEM flange won't slide off freely, you'll have to cut the tube, install flange and re-weld the tube. Most older parallel valve engines, just slide the flange over the tube. Mike can probably tell you the best place to cut the AV type tube.

The O-ring sits against the tube flange, the tube flange contacts the CNC'd flange metal to metal, just as the stock parts do. The silver ring inside the O-ring contains the O-ring in its cavity when it's compressed to provide the proper degree of squish.

You can rotate the tube with some force when the bolts are tightened down.

That is excellent design work!!! That allows for a tiny bit if head motion and still retain o-ring sealing. A few more hours on my bird and it is on the list for upgrade when the parts are off.

Keep up the good work, Team-Ross, kudos to Mike for initiative in action.
 
Ross - I must be missing something... In a previous post you suggested those of us with carbs wouldn't be able to use your fancy rubber tube connectors. I looked at our Lycoming O-360 tonight and can't see how I would need a rubber tube connector that's any different from what you've shown in your "kit contents" photo.

When you've got a moment to spare, would you mind educating me, please? I really like the idea of this product.

Oh yeah, I should mention that tonight I found two of the four cork gaskets on my rocker covers to be leaking. Geez it would be nice to have your fancy CNC machined parts there. Instead I installed my trusty silicone rubber gaskets in hopes they'll tide me over until I can afford machined rocker covers.
 
Gasoline is not so friendly with silicone so we supply standard Nitrile hoses and Viton O-rings when these are used on carbed engines.

If your hoses are in good shape and you like your old style clamps, you can re-use that hardware.

For some folks, their hoses may be long in the tooth and it would be appropriate to replace all the old parts with new stuff, hence the full kit if you desire.

It doesn't seem right to offer only a half solution for everyone.

We'll delete the parts you don't want and discount the kit price if desired though.
 
Thanks for the quick response, Ross. Now I understand the reference made to those of us with carb'd engines. One doesn't want one's intake hoses to turn to mush, thanks to them being exposed to an air/fuel mixture rather than just the pure induction air associated with a fuel injected engine.

I'm curious... The nitrile hoses you supply. are they any more flexible than the standard Lycoming parts? The Lycoming part seems to be both thicker and stiffer than what is needed for this task.
 
Thanks for the quick response, Ross. Now I understand the reference made to those of us with carb'd engines. One doesn't want one's intake hoses to turn to mush, thanks to them being exposed to an air/fuel mixture rather than just the pure induction air associated with a fuel injected engine.

I'm curious... The nitrile hoses you supply. are they any more flexible than the standard Lycoming parts? The Lycoming part seems to be both thicker and stiffer than what is needed for this task.

We are supplying Superior 08-00580 for the 1.5 inch tubes and OEM Lyc PN 69603 hoses for 1.75 inch tubes on carbed engines. I didn't spend much time trying to source other suitable suppliers for the carbed hoses.
 
Trevor was able to squeeze in another batch of flanges today before running other parts booked in a couple weeks ago.

I will run these to the anodizer tomorrow. Thank you to all the people who've contacted us to be placed on the order list. May be able to ship some of these out later next week if the anodizer is not too busy.
 
We are supplying Superior 08-00580 for the 1.5 inch tubes and OEM Lyc PN 69603 hoses for 1.75 inch tubes on carbed engines. I didn't spend much time trying to source other suitable suppliers for the carbed hoses.

Thanks for the follow-up, Ross. I spent most of tonight working on the engine and gave these induction tube clamps much thought... Perhaps they will be on the list for the next oil change.
 
Concerning the welding of the angle valve tubes- mine were factory welded about an inch down from the flange. I simply cut through the weld with a band saw, replaced the clamps and re welded. With a TIG at the ready, each tube took maybe 10 minutes to modify (not including paint dry time). I did not find it necessary to weld the tube in situ. The band saw cut was easy enough to re index. Really easy.
 
Thanks!!

Concerning the welding of the angle valve tubes- mine were factory welded about an inch down from the flange. I simply cut through the weld with a band saw, replaced the clamps and re welded. With a TIG at the ready, each tube took maybe 10 minutes to modify (not including paint dry time). I did not find it necessary to weld the tube in situ. The band saw cut was easy enough to re index. Really easy.

I like easy! My TIG work is getting better, but not this ready yet.
 
One of our customers just reported back that the Superior Cold Air Induction setup uses a tube which is expanded out to 2 inches so they are .250 larger than the factory type tubes and aren't compatible.
 
Superior sump/tubes

Is there any chance you?ll machine some that?ll work with the Superior sump/tubes? I?m sure there?s enough of us out here that there?d be a market for them.

Mark
 
Expanded out (tapered) at the sump end? If so, then a cut and weld like I did would work?

Yes cutting and welding will work just fine. The only thing that needs to change is the size of the rubber sleeve and the clamps. The rest of the tube is 1.75" in diameter. See picture below.

20180609_204457666_iOS.jpg
 
No problem to source the 2 inch hose and I'll check the clamp size availability today. Thanks for the feedback.
 
This is a great idea, but I'm not visualizing how it would all fit together on my carbureted O-290-D2. My intake tubes have flanges on the ends. So the new billet pieces (not sure what you call them) would slide onto the tubes and the flange on the end of the intake tube would seat metal-to-metal into the billet piece? Is that right? Then the O-ring would be inserted on top of the intake tube flange, and that shiny metal ring (not sure what you call that, either) would also fit on the intake flange inside the O-ring? Is the purpose of the metal ring to keep the O-ring spread? Also, I don't understand why would I need new hoses and hose clamps?

Maybe this helps:

2s0ecrl.jpg


The crush is determined by the depth of the counterbore in the new clamp (red, in this case). Unlike the standard Lycoming part which has the tube flange sitting proud of the surface of the clamp so that the paper gasket can form a seal, the O ring itself sits slightly proud. Most of it seats inside the clamp and all you have to do is tighten down the clamp tight to the head and you have your perfect preload. You can tighten the bolts all you want and never get a bow in the clamp or further crush the O ring. The inner retainer (the silver ring, not shown above) simply keeps the O ring circular (and from sucking into the tube).

2m5nds9.jpg
 
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Superior Cold Air

Thanks for the photos Mike.

I'll be picking up the 2 inch hose tomorrow. The CT clamps present a bit more of an issue. The hose OD puts the available clamps either near the minimum or maximum of their size ranges. Not so keen on either extreme without some testing. I can only source these clamps in minimum orders of 100 pieces each.

How to Superior owners feel about re-using their current clamps?
 
Thanks for the photos Mike.

I'll be picking up the 2 inch hose tomorrow. The CT clamps present a bit more of an issue. The hose OD puts the available clamps either near the minimum or maximum of their size ranges. Not so keen on either extreme without some testing. I can only source these clamps in minimum orders of 100 pieces each.

How to Superior owners feel about re-using their current clamps?

I don?t mind reusing my hose clamps if I have to. Also, I may have missed it somewhere and I guess I?m still a little confused on the installation, but am I going to have to do any cutting and welding on my intake pipes? Remember, I?m running the Superior cold air induction.
 
As there are many iterations of tubes, if your tubes are larger than 1.80 OD , you'll have to cut and re-weld after sliding the new flange on.
 
I have flanges in hand, picking up a bunch of rings this morning so we can start shipping this batch out this afternoon. I've contacted most of the people who PM'd me with interest.

Also have 2 inch silicone hose in hand now so can now fix up anyone with Superior Cold Air tubes.

This batch is near sold out now. I'll be scheduling in another run of flanges and rings near the end of the month.

Thanks to all who've placed orders :)
 
AWESOME!

My kit arrived today from Ross, a mere 6 days after I ordered it. I raced off to the hangar to get it installed. Very impressive kit, and I have high expectations of a lifetime of worry free intake leaks.

The kit arrived very complete and packed impeccably.
DSCN6291.JPG


It took a little figuring out how everything went together - it's a brilliant design!
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A bad picture of one intake completed. The most difficult part of the night was figuring out how best to compress the constant-tension clamps.
DSCN6298.JPG


I only had time to install 2 tonight - with unpacking, decowling and figuring it all out it took about an hour. I expect only another 30 minutes to do the other side now that I've "cracked the code".
 
Thanks for posting these photos Mike.

Lacking the dedicated tool for the clamps, I found a pair of channel locks worked well for compressing the clamps. You should have to do this job only once.
 
Good photos Mike. Curious about your installation process for the O ring assembly. Did you seat everything as shown in your second picture (above), and then place and install the bolts? If so, maybe you could try leave the O ring out and install the bolts only a few turns in (tube hanging - see first picture in post #32) then slip the O ring/retainer assembly into place. Once placed, draw the clamp up to the head with the bolts (being careful to keep the O ring centered).

The later method is how I installed mine; it would be good to hear your firsthand comments on the relative ease of either method.
 
Hi Michael,

After I installed the flange around the intake tube, I placed the O-ring in first, and then the retaining metal ring on top of the o-ring. I then pushed down on the metal ring to make it flush with the top of the flange and o-ring.

DSCN6294.JPG


DSCN6296.JPG


DSCN6297.JPG


This made installation pretty easy, as it all wanted to stay together.
 
Copy all. If you don't mind doing an experiment, try installing the O ring on the inner retainer first, then set it aside. Install the two bolts to hang the tube (big gap), then slip the O ring assembly in and draw the bolts up. Please report back with relative observations.

I have a set on order for the Rocket so it will be a while before I can try "your" method to compare.
 
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I use Mike's method as well, O-ring installed over inner ring, put bolts in a few threads, drop the O-ring and inner ring into the recess while holding the tube down, do up the bolts.

There is an arc cut into the face of the silver ring to aid in keeping the O-ring in place.

Good thing is once you get the bolts tight, you should never have to touch this stuff again.

BTW, we shipped out a bunch more today and some more will go out tomorrow to those who ordered and paid.

Another CNC run is scheduled for June 27th.
 
If you don't mind doing an experiment, try installing the O ring on the inner retainer first, then set it aside. Install the two bolts to hang the tube (big gap), then slip the O ring assembly in and draw the bolts up. Please report back with relative observations.

Michael - I tried your method, but I couldn't assure that the inner metal retained ring wouldn't slip out. The only way I could assure all of the parts were oriented correctly was by using my original method.

I did run into a frustrating situation on my #1 cylinder where the flange would want to slide down the intake tube while trying to get my screws aligned, causing the o-ring and metal ring to fall out. This was quickly remedied by using some electrical tape to hold the flange as high as possible during assembly.

DSCN6299.JPG


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I finished installing everything on Friday and went up for a test flight. Without exaggeration, THIS IS THE SMOOTHEST MY ENGINE HAS EVER RAN! I have always struggled running LOP - typically I could get down to about 10 degrees LOP (7.5 GPH at 24 squared), but any less than that and the engine would let me know. Friday I was able to go down to 6.9GPH and the engine was quite happy with me on my 0.7 hour test flight. I went for a 2.4 hour flight yesterday and experienced the same smoothness and ability to run lean.

DSCN6305.JPG



Thanks for a great product Ross! It's the single best upgrade I've made to my RV.
 
Great Product

Installed mine on M1B tubes. Had to chop them then reweld. All I can say is that this is a great product. Engines runs great after being plagued with induction leaks from poor custom made tubes. Thanks Ross!!
 
I'm glad that people are seeing some good benefits with these and actual running improvements. I'd just hoped to end the maintenance headaches always replacing gaskets.

A large batch of CNC'd flanges and rings will be completed today and will be going to anodizing tomorrow.

Thanks to all the folks who've PM'd and emailed me to place their orders.

I was not able to order the 1.75 CT clamps for the carbed engine induction hoses due to the high minimum order requirement so at this time, we can only supply these CT clamps for injected engines. I'll try to find a more agreeable source for these. In the meantime, people can use their existing clamps. I do have a large supply of Superior 1.75 hoses now for carbed engines.

I'd expect anodizing to be done early to mid next week and we can start shipping then.

I'll be contacting people shortly for payment and shipping addresses.
 
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I'm now on the list too, with plans to incorporate them into a Superior cold air sump upgrade this fall.
 
So, no take the $$$ up front and ship whenever???

Good on you Ross:D

For non-custom parts, we usually wait until we have the parts in hand before charging credit cards.

For CPIs and EFI kits and custom etched valve covers, we'll charge cards when we are about to commence working on them and try to ship pretty quickly after that, subject to supplier and our work backlogs.

We've heard that some other vendors take money 30-120 days before delivering any parts. We don't feel that's a fair way to do business.
 
Flanges in hand

Ok gents, I picked up the flanges from the anodizer this afternoon so can start shipping tomorrow. I'll contact those on the list first who've spoken for a set.

Thank you to everyone for your support and being patient.
 
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