3 into 1 exhaust

I was doing google's looking for info on triples with single exhaust and came across this site. Probably more info here than anywhere but still not too much on the inboard hydro exhausts utilizing jetski motors.

Few questions:
#1 Anyone have experience with this Skidoo manifold design? it physically displays the plugging theory for sure! (it appears to be a better looking option that the traditional LOG from the Yamaha motors 1100/1200cc)

#2 Anyone have pictures of the exhausts on these 1 litre mod hydro's? Specifically the triple jetski motors with single pipes. (found this picture with a manifold design but not the chamber/megaphone)

Attachment 56074Attachment 56075

Two, and three into one, is very common on 'sleds' since individual pipes take up so much room. I personally made a dual pipe set up for a customer (made expansion chambers at the time) so he could beat his buddy's sled. It made a bunch more power, but took up every available bit of space below the cowl.

Jeff

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Originally Posted by Mtrhead

I was doing google's looking for info on triples with single exhaust and came across this site. Probably more info here than anywhere but still not too much on the inboard hydro exhausts utilizing jetski motors.

Few questions:
#1 Anyone have experience with this Skidoo manifold design? it physically displays the plugging theory for sure! (it appears to be a better looking option that the traditional LOG from the Yamaha motors 1100/1200cc)

#2 Anyone have pictures of the exhausts on these 1 litre mod hydro's? Specifically the triple jetski motors with single pipes. (found this picture with a manifold design but not the chamber/megaphone)

Attachment 56074Attachment 56075

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RUSS Ran Inland Jets kawasaki 1100/900 pipe and set a kilo Record with it. I purchased a Inlandjet system yrs ago to measure the system.
It added made +20 hp over OE Exhaust System and really fattened up mid-range acceleration.
I had conversations with the original developer who is deceased.

Coffmans stills offers their aftermarket system for the Kawasaki 900/1100 ZXI/STX Jets

The later Kawai Jets 3:1 OE systems are very close and so no aftermarket was ever attempted.

In a multiple cylinder chamber design integrated into one expansion chamber, the design and length of the head pipes is critical. You design the system as if it was a single cylinder pipe, but with all the head pipes similar in design up to where they attach to the 'belly' of the expansion chamber. Good practice requires the VOLUME of the chamber and outlet pipe be larger than for a single, but the other parameters (reflection cones) remain the same as for a single.

Done a few of these and they worked well.

Jeff

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Originally Posted by Fastjeff57

In a multiple cylinder chamber design integrated into one expansion chamber, the design and length of the head pipes is critical. You design the system as if it was a single cylinder pipe, but with all the head pipes similar in design up to where they attach to the 'belly' of the expansion chamber. Good practice requires the VOLUME of the chamber and outlet pipe be larger than for a single, but the other parameters (reflection cones) remain the same as for a single.

Done a few of these and they worked well.

Jeff

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Interesting...header and diffuser length all seperate? then connect into the belly. That would a LONG manifold! I can picture the header...which is similar to my picture above of the polaris triple. But add the additional lenght of the diffuser and its almost a set of triple pipes with just the belly and converge cone. Never seen a pipe like that. Got any pictures?

To the PM's: Ive ported a few Lamey cylidner and Polaris cases for the hydroracer but never seen the exhaust setups. Just really curious since I run triple pipes on my GPR. I know the rules dont allow triples.

I have experience with that old Inland Jetpipe and the Coffmans on a Kawasaki ZXI1100. Inlands are hard to find..then OEM manifold though is awful small.

I have Russ' 1L now. On this Inland Jet pipe there's a gasket from the exhaust manifold to the pipe which keeps failing. Any thoughts?

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Originally Posted by halestorm

I have Russ' 1L now. On this Inland Jet pipe there's a gasket from the exhaust manifold to the pipe which keeps failing. Any thoughts?

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I talked to the mechanic at inland Jet before he died.
It is a great pipe.

The owner is friendly and helpful am sure he will help you.