MS'ing 45 degree V-Twin

newtyres1 · Post by **newtyres1** » Thu Mar 15, 2007 1:49 pm

Unlike the Buell system, you will also have an advantage in that you can reference the FPR to MAP.

Ian.

FIntruder · Post by **FIntruder** » Sat Mar 17, 2007 6:32 am

With a V-twin you will need to run a small canister and a choked down insert in the line to smooth out the pulses so the ECU can read it and the fuel pressure won't be bouncing around. Someone on here suggested using a valve in the MAP line to adjust the pulses out of it. A canister will allow for more volume which will change more slowly.
A FPR with a hose barb for MAP will have less fuel pressure at idle and cruise which may or may not be a good thing. The microSquirt will have to be adjusted accordingly.
There should be many adjustable FPR's on Ebay. Anybody have any experience with any to avoid or recommend?

FIntruder · Post by **FIntruder** » Sat Mar 17, 2007 4:19 pm

I checked the amperage draw dry on this pump. It pulled less than 1 amp just sitting there and less than two amps with my finger over the output side hose barb. Even if it will pull 3 amps worse case scenario that is fine with me. Feels good to not be worrying about how the pump situation is gonna work out with a resistor or PWM or...............
All thanks to me and my hard work. Oh and Dr. Hess for finding the pump in the first place.

Dr.Hess · Post by **Dr.Hess** » Sun Mar 18, 2007 6:05 am

Us shareing our findings is how this whole MS got together and is really what the strength of the Internet is. Also why Hillary wanted to kill it in its infancy, but that's another story.

Anyway, yeah, I can see where there would be a pretty good pulse on the MAP line with a V Twin. Motors with ITB's like my 4AGE 20v also have a real problem with the MAP pulse. I have mine smoothed out pretty well with 2 030 MIG tips in series, then a small engine/MC type fuel filter, then the MAP sensor. I'll try that with the Sporty. muythaibxr uses an aquarium air accessory valve in line and tunes that until the MAP pulse is smoothed out. I bought an aquarium valve, but it leaked air on me. Should have gone with the more expensive metal one.

FIntruder · Post by **FIntruder** » Sun Mar 18, 2007 7:40 am

I also have a Suzuki TL1000S V-Twin and it uses a small, size of a fuel filter, canister and a plastic fitting that I assume is choked down to quell the pulses. From the manifold it goes to the choke, then to a Y fitting that splits to the canister and the sensor. Suzuki calls the choke/valve part a VTV, Vacumn Transmitting Valve and the canister a Vacumn Damper. Unlike a fuel filter, the canister has only one fitting, did you just cap one end of the filter or is it in series?

What kinda engine is that in your Super Seven?

Dr.Hess · Post by **Dr.Hess** » Mon Mar 19, 2007 5:08 am

We just put the fuel filter in series with the MAP sensor. Mine goes: Manifold (and pick a good vacuum source, on the 20V Ken sacrificed a spare manifold and found the collector area), MIG tip, MIG tip, fuel filter, MAP sensor.

I could see that T'ing it in would work also, but then I'd need a T and a cap. Interesting that a OEM came up with the same solution.

I have another 4AGE 20v Silvertop for the Seven. It was in my MR2, and I ran a factory computer on it. I think I'll leave it with the factory ECU in the Seven. I mean, it works and I already have it.

Dr.Hess · Post by **Dr.Hess** » Wed Mar 21, 2007 11:43 am

I bought an adjustable FPR on eBay:

$35 including shipping.

FIntruder · Post by **FIntruder** » Wed Mar 21, 2007 2:37 pm

That is the one I have been lookin' at and will probably go with. Ya got the pressure gauge right there and its pretty small.

newtyres1 · Post by **newtyres1** » Fri Mar 23, 2007 12:56 am

Here's an 8-1 wheel I got made up for the Buell. Hopefully (a big hopefully) it'll bolt straight in to this Harley Sportster-based motor, using the original hall sensor. I need to do some more bench testing first, and finish the fan control cct (this has been a challenge, since it is a 2-speed fan using pwm for half speed, and has different turn on/off temps depending on whether the engine is running or not etc etc) and try to get PalmTune working with MS2 (another big one since I'm not experienced), and then get hold of a uS. When I work out the orientation of the wheel on the camshaft I need to drill it near the center and fit a short rollpin to locate it. So I have plenty to keep me busy for a few weeks or months or so. It's good to see your progress Dr Hess, I hope it all goes together nicely. All good clean fun!

Edit - the tooth on the RHS is not bent, I've checked it many times since looking at that pic!

FIntruder · Post by **FIntruder** » Fri Apr 06, 2007 4:21 pm

So hows it runnin' ? What progress have you made?