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Discussion Starter #1 (Edited)
Ok, this is going to be an interesting diagnosis I think... I've transplanted the engine into a Polaris RZR, it runs great ...up to about 9000 RPM's in first gear and about 7000 in other gears. I haven't been able to drive it a whole lot, you can tell it wants to accelerate but it just won't. I don't believe it is a spark issue, and I believe that it is getting enough fuel, I am dumbfounded. It is NOT throwing any codes (I unplugged the vac line to the MAP sensor and it did throw a code, so it is capable of throwing them)... I have an aftermarket fuel pump and regulator, I have set the fuel pressure at 45 to 55 lbs to see if anything would change, it didn't change when I changed the fuel pressure, and the pressure stayed constant while I was driving it, nor did it didn't change when I changed the fuel filter (pre-regulator, so it shouldn't matter, but I did just so that I could rule it out). I have also changed out the coils, it acted the exact same. I'm not sure if it's rich or lean when it falls on its face, we don't have any dyno's around to wideband it. Any ideas?
 

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Discussion Starter #2
Could I need to get a PCV and autotune? I don't think the intake/exhaust is that much more free flowing or restrictive than factory :banghead:
 

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Discussion Starter #5
it doesn't stick, it is just like a soft rev limiter, in any gear it is "normal" until 7-9000 rpm's, if you give it any more throttle it falls on its face
 

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Discussion Starter #8 (Edited)
I have an equipment air filter housing with a two stage air filter that should flow enough for the 600, I took out the secondary air filter to verify that it was not lacking air because of the filter, it ran the same. after the air filter, it goes into the intake box by way of about an 80 degree turn, the smallest intake tube before the air box is 3 inches inner diameter, I have the throttle bodies mounted on one side and the shower injectors mounted on the other, they are in line. after that they all go through the intake runners which are as close to identical as I could make them and the same inner diameter as the throttle body. I don't think that the intake is an issue. It has been a couple years since I made the box but I tried to make it as close to the factory air box as I could, obviously there are a couple more bends but it doesn't have any velocity stacks in the airbox, I figured that the intake runners would take their place.
 

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You added about 5 inches of length between the injectors and the head. The tbs usually sit right on the engine. How cunty would it be to sit the tbs right on the engine and try that?
 

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Discussion Starter #11 (Edited)
It seems to be a fuel mapping issue, I took it to the dunes for the day and messed around with the fuel pressure regulator. for the sake of diagnosing the issue, I turn the fuel pressure down until the engine shut off and then turn the fuel pressure back part of the way. I drove it around a little bit and fine tuned it with the fuel pressure regulator but it still seems like it is too rich top end when it is correct on wthe bottom end ... which probably has to do with the longer intake runners and the exhaust that I fab'd. it runs like a raped ape when it is running correct on the top end. thanks for your help guys! eventually I will get a video for you guys. I will be looking for a power commander really quick.
 

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Call me stupid. But aren't the injectors 'timed' with the intake valves? So they deliver fuel at the right time to enter the cylinder?

In your case, having the injectors way far away from the engine you may not be getting all your mixture into the cylinder because the valve is shutting. This could lead to fuel pooling in your ports and a huge decrease in performance.

Seriously try to get the tbs back on the engine as they were. I'm pretty sure Honda engineers got that part right
 
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