the PVC manifold didn't go so well so now I'm making one from copper plumbing parts

[chuck c]

BAH! I can't seem to get around having to do coping. That's not easy to do well even when you have the right tools. I'm about to give up on coming up with a really easy anyone-can-do-it with hardware store parts kind of design. If I allow things that are a bit more involved it opens up more and much cleaner looking designs. Probably work better too.

 

[mcgovern61]

chuck c » Sat Oct 18, 2014 9:31 pm[/url]":1ovlhy19]
Of course if you can bend any way you like you can do this. It might be flexible enough to not need rubber splices. Those big bends would let it flex.


How I spent my saturday night....

Late to the game here, but the only thing I can say about this design is that it is very near the Suburu design for their boxer engines with the up-swept manifold. Granted, the Suburu carb was a side draft:

 

[chuck c]

Yes, I have 2 Subarus at the moment. Excellent cars. They are what made me a fan of the boxer engine and looking at Goldwings.

 

[chuck c]

oooooooo so close. It just hit me that exhaust flanges are the right shape and close to the right size. The Wing's hole spacing is 60mm and the exhaust flanges I can find are 70mm. If anyone happens to know a bike with 60mm spaced exhaust flanges, DO let me know!

The Solex is also 70mm.

 

[chuck c]

The center hole is dead on, thickness good, hole size roomy for the Wing's 8mm but perfectly acceptable. Price of $8 is very acceptable, I doubt I'd find them any lower. Hole spacing 50mm. So very close! I could slot the holes a few mm and make it work. The roomy holes even give me 2mm more.

Great for DIY builders who would like to make their own GY6 exhaust or custom pluming and connection for specific projects. Laser cut from mild steel, ready to be welded!
Thickness: 3/16" (5mm)
Center Hole 1-5/16" (30mm)
Bolt Hole Size: 7/16" (10mm)
Bolt Hole Center to Center: 1-7/8" (50mm)
$8.00

 

[chuck c]

SUCCESS!
F5502101
Yamaha F6V
ID 1.50"
Hole spacing 2.36" / 60mm
long 3.05"
wide 2.26"
hole .340" / 9mm
It's perfect! They want $20 apiece for them. But now I know what machine I can find them on! So what is a Yamaha F6V? I think it's a typo and they mean FZ6R.

They also sell this that might work
F138-2CNC-VW
VW
ID 1.375"
2.283" / 58mm
2.95"
2.15"
.340"

 

[dan filipi]

Sounds like a winner.

So the plan is to solder or braze them to the copper 90's?

 

[chuck c]

There's also this
MIKUNI I-VM28-200-1 002-050 RUBBER INTAKE MOUNTING FLANGE MANIFOLD
which is also the right dimensions and actually made to do the job but they run $27 each.
I might have to hit the junk yard saturday and see if I can find a set.

 

[chuck c]

dan filipi » Mon Oct 20, 2014 10:11 pm[/url]":1wp237x8]
Sounds like a winner.

So the plan is to solder or braze them to the copper 90's?

Yup. But I think I'm going to see if I can dig up a set of those Minuki carb boots first. The steel flanges are $20 each, no flex, and still need a gasket. The carb boots are so perfect for the job and only a few bucks more I might have to bite a bullet and spring for them. Why didn't I think of them sooner? :doh:

 

[chuck c]

I just found them for $20.48 each on ebay. I've got to do it.

 

[Ansimp]

chuck c » Tue Oct 21, 2014 9:17 am[/url]":3n5d321q]
Yes, I have 2 Subarus at the moment. Excellent cars. They are what made me a fan of the boxer engine and looking at Goldwings.

The Subaru manifold goes down but there is only air in it not fuel. The injectors are almost directly into the head :yes:

 

[chuck c]

Ansimp » Tue Oct 21, 2014 10:47 am[/url]":2xuaewzi]

chuck c » Tue Oct 21, 2014 9:17 am[/url]":2xuaewzi]
Yes, I have 2 Subarus at the moment. Excellent cars. They are what made me a fan of the boxer engine and looking at Goldwings.

The Subaru manifold goes down but there is only air in it not fuel. The injectors are almost directly into the head :yes:

Newer ones yes but I think some are TBI which might be the case in that pic. The TB is on the backside where the air tube comes it. I think pooling is less of a problem with TBI, they don't dump gas like a carb can.

 

[Ansimp]

No Chuck that is a TPS. All Subaru fuel injection has been multi point injection and there were no TBI offered. The earliest fuel injection was on an 85 ea82 engine that came fitted to Touring Wagons and is the engine series that most resembles a GW engine. If you look closely on the left hand side of the photo you can see the two injectors right near the spark plug leads.

 

[chuck c]

You're more up on Subarus than I am and I've owned 4! That's because the darned things just run. I don't have to get under the hood much. Their one weakness is the head gaskets and when they go the engine must come out to replace them. I've seen many really nice ones go to junk because it cost more to fix than it was worth.

 

[chuck c]

Back in topic, since i realized a standard Mikuni carb boot will do the job of connection to the heads, my very first design in PVC will work. With no more 7* angle to fight I should be able to do what I originally set out to do: a DIY manifold that anyone can make for around $100. Stand by.

 

[Ansimp]

chuck c » Wed Oct 22, 2014 8:52 am[/url]":3ef2asnw]
You're more up on Subarus than I am and I've owned 4! That's because the darned things just run. I don't have to get under the hood much. Their one weakness is the head gaskets and when they go the engine must come out to replace them. I've seen many really nice ones go to junk because it cost more to fix than it was worth.

When I changed the clutch I couldn't bring myself to change the head gaskets as they were only leaking a little oil from where the gasket material was delaminating. Even though I had new ones I just wanted the car back on the road ASAP. If the oil leak gets worse or the gasket fails I will just have to do the job properly with genuine Subaru head gaskets as recommended by my Subaru mechanic mate. After Christmas he fitted about 10 sets in about 6 weeks, he turns the whole job around in the day using a machine shop that responds to a cash incentive ( machined while he waits) :yes:

Carport workshop

• Ansimp
• May 15, 2014

:0fftopic:

 

[chuck c]

Just like this:

Tossing the OEM intake horns gets rid of that obnoxious 7* angle and widens the centerline between the runners by 30mm. That makes enough room for the big chunky PVC parts and allows 90s and 45s to work. 2 of the 45s and 2 sides of the cross still need to be trimmed a bit but there's still plenty of plastic to do the job. But now seeing this chunky looking thing I'm thinking I might declare victory on PVC and leave this for someone else to do. With this info it shouldn't be hard to follow. This does put the PVC much closer to the heat of the head but the flow may keep it cool enough. The Mikuni intake adapters run about $22 apiece and the PVC parts another $15. Really close to my $100 target.

As I already bought $50 worth of parts, I'll make mine in copper. That should put my final price at close to $150. The intake adapters will be different bores for PVC and copper. I will try to find Mikuni parts for both and give their part numbers.

There's one more advantage to this layout. The runners are exactly the same total length. With some of those copper layouts I posted I was worried the right and left sides would fight each other pulling back and forth through a single 1" tube from the tee in the center to where they split to go to the cylinders. It might be nothing but it's definitely not a smooth flow in that area. When one side draws the direction of gas at the tee might actually briefly reverse the flow in the other side. That means its next charge will be less dense. It might only happen at a certain resonant RPM. The cross eliminates that and allows the flow to switch between runners smoothly and make a one-way trip.

I will still need to make and fit a flange to the copper but I don't forsee and problems with that. :hihihi:

 

[Ansimp]

opcorn: opcorn: :good:

 

[chuck c]

Drawing and parts list.

How about some aluminum sheet heat sinks between the head and intake to help prevent the pvc from getting too hot?

I like the idea of a bit of screen in the hole to catch hardware on its way to the intake valve.

 

[ekvh]

Watching with interest. You probably have, but just checking that you have enough height to clear the coolant tubes.