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1150 EF updating project

I have continued the EFI tuning, but it seems to be impossible to get it running good between 2000 and 3500 rpm in steady speed on highway riding.
Under a light acceleration it runs fine and under boost it really goes.
I check the spark plugs after a slow highway riding (2000 - 3500 rpm) and #1 & #2 was a light brown, #3 was black and #4 was light gray.
I have changed the injectors, the spark plugs and the spark plug cables, but no help.
It seems that there are some starange suction impulses in the plenum.

Next thing is to change the cam timing.
 
wow

wow

all i can say is right on man.... now thats how to make power!!!!
keep the photos coming im watching and saving cash right now....
got to have one.
 
I have continued the EFI tuning, but it seems to be impossible to get it running good between 2000 and 3500 rpm in steady speed on highway riding.
Under a light acceleration it runs fine and under boost it really goes.
I check the spark plugs after a slow highway riding (2000 - 3500 rpm) and #1 & #2 was a light brown, #3 was black and #4 was light gray.
I have changed the injectors, the spark plugs and the spark plug cables, but no help.
It seems that there are some starange suction impulses in the plenum.

Next thing is to change the cam timing.

I still believe that you have far too much valve overlap for a road going supercharged machine. You also did some pretty radical inlet porting from memory, which will be causing inlet pulses at lower flow rates. Usually a good seat radius job and some minor port reshaping is all that's required for SC mods.
SC Cams usually include a higher lift for the exhaust over stock.

Check out that supercharged cam timing link I gave you earlier on in this post.
You will notice that the overlaps are a lot less than what you are running at present.
Some of your problems could also be associated with the plenum design.
 
I still believe that you have far too much valve overlap for a road going supercharged machine. You also did some pretty radical inlet porting from memory, which will be causing inlet pulses at lower flow rates. Usually a good seat radius job and some minor port reshaping is all that's required for SC mods.
SC Cams usually include a higher lift for the exhaust over stock.

Check out that supercharged cam timing link I gave you earlier on in this post.
You will notice that the overlaps are a lot less than what you are running at present.
Some of your problems could also be associated with the plenum design.


I?we got cams now: in 15/61, ex 55/19. I?m going to try next: in 18/58, ex 64/10.
If that does not help, I need to made a new different shape plenum.

I try to look that link, but it does not work.
 
I?we got cams now: in 15/61, ex 55/19. I?m going to try next: in 18/58, ex 64/10.
If that does not help, I need to made a new different shape plenum.

I try to look that link, but it does not work.

I didn't realise that the MR2 link is no longer active. That's a shame, as there was some good info on that site. I thought that I had saved that info, but somehow I overlooked doing that.

Do you mean that you have tried the 15/61-55/19 cams and you are still experiencing that surging effect when cruising? If that's so, then your plenum pressures must be causing your problems.

There's a school of thought that recommends fitting a turbine type SC instead of the gear positive pressure blower that you have chosen. Their logic is that you run stock NA cams and compressions so that the bottom end performance (up to 3000 rpm) mimics stock figures. From then on, the turbine takes affect, and you get the type of grunt you get from a turbo, but without the heat issues, or bottom end lag. The other advantages of this system are that you don't blow unburnt gases straight through the cylinder at lower rpm and the boost keeps rising with rpm increase, just as a turbine should!!

I can give you some more info on turbine type SC's if you decide to take that option.
 
I didn't realise that the MR2 link is no longer active. That's a shame, as there was some good info on that site. I thought that I had saved that info, but somehow I overlooked doing that.

Do you mean that you have tried the 15/61-55/19 cams and you are still experiencing that surging effect when cruising? If that's so, then your plenum pressures must be causing your problems.

There's a school of thought that recommends fitting a turbine type SC instead of the gear positive pressure blower that you have chosen. Their logic is that you run stock NA cams and compressions so that the bottom end performance (up to 3000 rpm) mimics stock figures. From then on, the turbine takes affect, and you get the type of grunt you get from a turbo, but without the heat issues, or bottom end lag. The other advantages of this system are that you don't blow unburnt gases straight through the cylinder at lower rpm and the boost keeps rising with rpm increase, just as a turbine should!!

I can give you some more info on turbine type SC's if you decide to take that option.


Yes, I have now Yoshi stage 1 cams installed in15/61- ex55/19.
First thing I?m going to do is put a "damper" in the map sensor hose.
If that does not "smooth down" the problem zone, then the cam re degreeing and then a new plenum.

A centrifugal supercharger would be easier to tune, but I have chosen this "stone age" roots-type supercharger and going to try to live with it.
Maybe my next bike would be with centrifugal sc or turbo.
 
I start to make a new plenum. I redegreed the cams, but no help for the problem.

The new plenum is a WRC-type:

kotelo2-1.jpg


kotelo1-1.jpg
 
I?we got cams now: in 15/61, ex 55/19. I?m going to try next: in 18/58, ex 64/10.
If that does not help, I need to made a new different shape plenum.

I try to look that link, but it does not work.
Will you please just put BOTH the intake cam & exhaust cam in at 108 lobe centers! I GUARANTEE you will see improvement! Stop spreading the cams apart on a forced induction system. Ray.
 
Will you please just put BOTH the intake cam & exhaust cam in at 108 lobe centers! I GUARANTEE you will see improvement! Stop spreading the cams apart on a forced induction system. Ray.

The most of the supercharger cam specs I have found from different manufacturers have a 112 - 117 lsa.
If that plenum modification help or not to get the engine running smoothly in steady speed, I?m going to try that 108 lobe center. One "turbo guru" say: 110/110 would be good for forced induction.
It would be interested to know if anyone have ever made a real superchrager cams for GS 1100 or 1150 engine and the cam specs...
 
I change the plenum today and redegreeing the cams. Cams are now: in 18.5/59, ex 64/17.
After testride I check the spark plugs, #1 & #4 was light gray and #2 & #3 was light brown.
In steady speed it was better, but there was still some "jumping" between 2500 -3000 rpm. Engine pulls stronger, than before.
I try to get that problem zone better with fine tuning the efi ignition and fuel map.
 
I have been adjusting efi today and get the engine running good enough. There is still some roughness around 3000 rpm, but not much.

Pic of new plenum :

22062009.jpg



Next thing to do is raise the boost and install the lock up clutch.

There is a lot more valve gear noise after the cam and valve spring change.
The valve lash are set to 0.15 mm.
Is this noise normal with harder springs and Yoshi cams?
 
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Being tired to listen the blower howling in highway speeds I think to do something to the dump valve. The dump valve "blows" the supercharger noise right to my face.

After some hours working with the lathe and the bridgeport the bov is modified.
Now the out blowing is easier to point to the side.

27062009_003.jpg
 
Why use a dump instead of a bypass? Wouldn't that take the load off the compressor in steady state riding when you don't need boost?
 
Why use a dump instead of a bypass? Wouldn't that take the load off the compressor in steady state riding when you don't need boost?

There are a bypass and a dump, as you can see in pics on page 29.
The dump is vacuum/spring operated and the bypass is pressure/spring operated.
 
There are a bypass and a dump, as you can see in pics on page 29.
The dump is vacuum/spring operated and the bypass is pressure/spring operated.

Aha...I missed that on the first time through.

Why did you choose to plumb it that way? I would have expected them to be the other way around, so the bypass lets the SC basically freewheel under vacuum(cruise) conditions and the dump protected against overboost.
A double-acting valve on the bypass would handle both conditions for you, too.

EDIT: Going back through the thread, it looks like you originally had it plumbed the way I suggested? http://www.thegsresources.com/_forum/showpost.php?p=768613&postcount=218
 
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Aha...I missed that on the first time through.

Why did you choose to plumb it that way? I would have expected them to be the other way around, so the bypass lets the SC basically freewheel under vacuum(cruise) conditions and the dump protected against overboost.
A double-acting valve on the bypass would handle both conditions for you, too.

EDIT: Going back through the thread, it looks like you originally had it plumbed the way I suggested? http://www.thegsresources.com/_forum/showpost.php?p=768613&postcount=218

There was some difficulties to make engine idle after to close the throttle and also some delay when twisting the throttle, because a volume between the throttle body and the engine was so big.
Now it acts like "normal" bike.
 
The project is near to be finished. Today I put the lock-up in, rise the boost and change a new brush holding assembly with new brushes to the starter motor.
The clutch is better now than before. The boost rises only about 2 psi, but it?s more than before and the engine feels a bit more powerfull.
The starter motor is much better than before.
I?m going to take the bike in the dyno soon.
 
The riding season is almost over and my bike is still not dynoed.
I made a lot of efi tuning and now the bike acts almost like a "normal" GS.
The 3000 rpm problem zone is ok now. Reason was too rich air fuel mixture.
The LC1 shows the right numbers, but when i leaned the fuel map 10% in that
area the "jumping" was away and LC1 still shows the same numbers (14.0)!
I rode about 15 miles not rewving ower 3500 rpm and check the spark plugs after that.
There was almost no difference in spark plug colors.
Now im happy it?s rideability. There can be more power, but is it ever enogh?
Maybe i can rise the...
 
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