Is the udp4port combo pipe same as the go efra 2072 pipe n manifold?

The UDP pipe is shorter in chamber length (by quite a bit).
The performance is different - on the UDP motor anyway. Looks like the shorter chamber pipe was specifically designed for the "original" UDP / Champion 4 port motor.

Meaning to say by using original go efra 2072 with udp combo manifold will get diff effect of powerband?

No. To the best of my knowledge only the chambers are different. The headers are unchanged.

Got it. Thanks. Bought d 2072 hard coated today n found out the chamber is identical but maybe difference in diameter n length

All 2072 pipes are identicle , there is no difference in the chambers what so ever.

Reason for this is the pipe has a Homogolation Number http://en.wikipedia.org/wiki/Homologation

its EFRA 2072 , it cant be changed or the number has to change.

Hey Ozzi !

Awesome video ! sounds great and i can see you are having traction problems too lol

One thing i noticed the engine was bogging off the mark half way through the tank. This could be for 2 reasons. The Clutch Collet is worn and slipping or the HSN may be a tad lean.

Check these and if you need more help let me know !

Cheers

M

Hi Mark,

This was the pipe released by Robust Chen for the UDP 4 port (and engraved as such).
The chamber was definitely shorter, as customers had to make up new exhaust brackets and cut their bodies out more to accommodate the shorter pipe.
We measured the headers and they were identical. You could see the pipe had a faster taper in the rear section, making it somewhat shorter in the chamber section overall.

I can't explain why - just saying there was a distinct difference

EDIT: I've dug up a couple of pics. Both pipes are black hard coated 2072's.
The one on the GXII-5RHO engine is the original 2072 as we know it.
The one in the UDP promo is the shorter one we received. If you look at the tapered section at the rear of the chambers on both pipes you can see the one on the GXII-5RHO has quite a long slender taper, while the UDP one has a shorter faster taper, giving the pipe an overall shorter and stubbier look.
From memory I'm guessing the UDP pipe was a good 95mm - 100mm shorter in overall length.
I held both pipes in my hand side by side and the difference was plain to see.

I agree - all homologated pipes should be the same, but these did differ somewhat. I guess only Robust Chen can answer that one.

Thanks for that Mark, I will check it out. I have pulled the clutch off since taking the video & noticed the hard shoes were worn down close to the wear marks, I was running 4x .9mm springs, have changed to the medium shoes (partly worn, need new ones), & 4x 1mm springs to try out, the flywheel was pretty tight so I would say the tune is off a little like you mentioned.
The HSN is maybe half a turn below housing but when I did richen it a little more it would bog a little on the top end, I wasn't sure if I should richen HSN to level with housing & lean LSN more, although the bottom end seemed alright.

Looks like some interesting things going on with Go. I am working with Richard the Go dist. in the Usa on selling the new Go .56 gasoline heli engine. I also see on go's site a .28 gas 1/8 engine in the future, cant wait!

Rex

A few posts ago Mark talked about some of the Champion engine features. How about the UDP engine? Can anyone talk about what that engine has to offer? I am also curious to know how the GXII-Plus, Champion, and UDP compare and contrast with each other.

Hi Rich,
The UDP was a new design from GO when Robust Chen was in the position of Race engine design.
It was an all new 4 Port design - good little motor.
Some markets didn't like the Underdog Project title, so the motor was also released as the Champion in these markets about 6 months into production.

When Robust left GO, these engines were taken off the market, and the GXII Plus was released soon after.
The GXII Plus was a progression of the the very well received GXII 5RHO engine.

With a warehouse full of UDP/Champion crank cases etc, GO re-released the Champion block and cooling head with a 5 port sleeve and the new 2 needle carb to clear the warehouse of dead stock.
This is the Champion motor people now refer to.
I believe it's being sold ex factory for eBay type marketing, along with the Cera motor talked about on here.
Both are limited number releases - until the old stock has cleared.

I'm guessing the re vamped Champion is very similar to the older GX5R 5 port. It may even have inherited that sleeve, or a slightly re vamped edition.
All the GO 5 Ports are pretty strong motors.
The older GX5R was legendary for its stump pulling bottom end. The GXII 5RHO was a little smoother, and now the GX II Plus even smoother again with a bit more top end.
GXR and 5RHO motors were suitable for truggy and buggy, with the current GXII Plus being more of a buggy motor. The UDP was a smooth buggy motor as well.

Hope that gives you a better idea.

Just wondering of anyone has used a gxii-5rho with the OS P3 plug?
I was using O'Donnell plugs but had an OS put in by accident. Due to the different tapers I'll be buying another head button anyway, but was thinking of having both handy in case I ever need to use OS plugs again. That way I can just swap the head button.
I believe the p3 is a slightly colder plug than the OD 97T, so would it be better suited to the warmer conditions that we are going into here in Australia? Or do they not really work?

Cheers

The O'Donnell 97T is a medium heat plug. The OS P3 is an ultra hot plug.

Guys here use the OS P3 with no issues in the GO engines.
The ultra hot OS P3 would be good in humid conditions.

Imo Os p3 is good plug, but if the ambient temperature hit 35c and above, p4 will be good else the plug wont last. I tried p3 with 35c and it only laster 2-4 tanks.