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Discussion Starter · #1 ·
i just built my motot, 734, r e + 2 head, x4 cam, bored tb, k&n, it was running pretty good when i added the msd, i turned the fuel all the way up and it still needed more so i bought a rc 550 cc injector, it is so rich i turned the msd down to 25 % below the level five mode. is this commen and i just need to keep goin? or does it sound like something is wrong.
 

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nwrhino; The stock injector should be enough for the mods you have going. I really don't see it running static, AT ALL, but you do want the duty cycle to be "up there" in percentage anyways... That said, you have a 550cc now, but you also have the wrong fuel controller for the mods you have...
 

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Discussion Starter · #5 ·
the injector nozzle is shorter then the stock one, the oring did have a little nik in it, but it was where it went into the rail.
 

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James, if you had a nick in the injector o-ring at the fuel rail connection, and it was big enough to cause a problem, and with the pressure of the fuel... Wouldn't you have fuel spray out of the rail as well as into the rail, thereby actually causing a "lean" condition?

But I agree, no nick is a good nick :) And lube those rings before putting them back in.

All that said... RC injectors are the red-headed step-child of injectors in the 700 world... Take no offense nwrhino, my opinion only. ;)
 

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James, if you had a nick in the injector o-ring at the fuel rail connection, and it was big enough to cause a problem, and with the pressure of the fuel... Wouldn't you have fuel spray out of the rail as well as into the rail, thereby actually causing a "lean" condition?

But I agree, no nick is a good nick :) And lube those rings before putting them back in.

All that said... RC injectors are the red-headed step-child of injectors in the 700 world... Take no offense nwrhino, my opinion only. ;)

thats what i thought to..maybe the computer does something to compensate for the lean condition or the low fuel pressure
 

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Discussion Starter · #10 ·
im starting to think that my pc3 might be turned up and now with the bigger injector it might just be dumping fuel too it.
 

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I have had good luck with an MSD and a Raptor 700 injector on units that required more fuel. Just my 2cents.

Nate
Alba Racing
 

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thats what i thought to..maybe the computer does something to compensate for the lean condition or the low fuel pressure
Stock ECU cannot control the fuel pressure... Or any "piggyback" unit for that matter. But if the o-ring worked for you, then it's worth a try or at least looking into.
 

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im starting to think that my pc3 might be turned up and now with the bigger injector it might just be dumping fuel too it.
Didn't catch that you were running the PC3 in conjunction with the MSD box, assumed you weren't running the PC3 because you didn't have the proper connector for power to program that unit.

All that said though, a 550cc RC is way too much injector for that build (in my opinion). And I wouldn't be trying to control the fuel map with both the MSD and the PC3, pick one or the other (which means, pick the PC3). Remember, all these units are doing is adding or subtracting fuel from the stock fuel map the Rhino comes with. In your case, it's like having 3 devices messing around with fuel delivery ;)
 

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I have had good luck with an MSD and a Raptor 700 injector on units that required more fuel. Just my 2cents.

Nate
Alba Racing
Nate, while I do agree with you on the raptor injector being a good replacement for this build, we'll disagree all day long that his MSD unit can even come close to controlling his fuel properly ;)
 

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I have had good luck with an MSD and a Raptor 700 injector on units that required more fuel. Just my 2cents.

Nate
Alba Racing
Nate, while I do agree with you on the raptor injector being a good replacement for this build, we'll disagree all day long that his MSD unit can even come close to controlling his fuel properly ;)

This is a debate that I have had 100 times over and can only answer that If it is not possible I better start calling a bunch of customers and tell them to bring there Rhino's back...

Nate
 

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This is a debate that I have had 100 times over and can only answer that If it is not possible I better start calling a bunch of customers and tell them to bring there Rhino's back...

Nate
Nate, I didn't say it wasn't possible to run nwrhino's setup with an MSD, I merely said you couldn't come close to doing it properly.

But out of curiosity, is it Alba Racings position that a Rhino being brought in for the mods like what are being discussed in this thread, ie. 734mm bore, Racer's Edge ported head with +2 valves, Megacycle x4 cam, bored throttlebody, k&n intake, and not mentioned but likely added, a performance exhaust system.. Is "properly" let out of the Alba Racings doors with an MSD unit capable of only a 2D fuel map being installed?
 

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Yes, if the EGA shows proper A/F ratios on a consistent basis I would say that is a "properly" tuned vehicle. That is the advantage of having the proper tools to tune a vehicle. I think our consistent results and long time presence in the GNCC, WORCS, SCORE, and Factory race teams demonstrates our ability to properly tune vehicles.

Nate
Alba Racing
 

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Discussion Starter · #18 ·
thats why i have the pc3 stacked with the msd, i will use the msd for wide open, then adust the bottom to mid with the pc3, i disconnected the pc3 and made another map with the msd last night, it did run alot better and i got my af around 12.5 at wide open, but it stutters and pops a little in the mid, so im gonna go get the 9 volt adapter for the pc and try to fine tune with that. as for the msd i have been told by a few guys that it wont be enough by itself when you get into building these motors, thats why they stack the pc on it. i will let you guys know how it goes, thanks for all the help, if the thing had jets i would of been done by now, lol
 

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Yes, if the EGA shows proper A/F ratios on a consistent basis I would say that is a "properly" tuned vehicle. That is the advantage of having the proper tools to tune a vehicle. I think our consistent results and long time presence in the GNCC, WORCS, SCORE, and Factory race teams demonstrates our ability to properly tune vehicles.

Nate
Alba Racing
Nate; As far as the race series that Alba has been involved with/sponsored, I commend your company on supporting these racing series. It's support like that that keeps them going.

That said, we're talking about specific motors in this thread, specifically Yamaha 700's. And there has never been a Yamaha 700 based motor with the mods mentioned in this thread that's been "properly" tuned by anything short of a 3d fuel controller (in combination with another controller capable at the very least of 2d timing, prefereably 3d timing). You know it and I know it. Which is why NOBODY that uses an EFI 700 base modded to this degree uses anything less than a unit capable of producing a 3d fuel map. Why do all those mods and leave power on the table? The "new" model MSD for the Rhino? That one sounds appealing. And I've used the software that will be programming this unit. But guess what? It's 3d... Wonder why?

Back to the original topic... Your suggestion of a raptor injector wasn't bad. The RC550 is too much injector. nwrhino has the right equipment currently, as far as the MSD and the PC3, just not using them in the proper fashion for his build. Using a 550cc injector though.. Hurting the ultimate performance of this motor. PW/DC taken into account (among other factors...), the raptor injector is a much better solution.
 
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