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Injector relocate

TRS

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Stock reeds in it so they should be the 3R. Where I had fueling issues was on the top end. Started at 12.0 WOT under boost, (10 psi) was like you hit the kill switch when it went under boost. Backed it off to 12.5 and it halfway choked out. Ended up at 13.1 or it would not run under boost. Bottom end was as strong as a stocker all the time though.

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I am running 60pump/40Sunocco110. At 8-9# of boost it likes 13.2-13.4 AFR. This is at 8-10,000'. With stock head, timing, and on the eth setting. O2 sensor, picture.
12 PRO.

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50/50 av gas, 10 psi. Stock head as well. Guess they just like it a little lean. Good to know I'm not out in left field. Honestly probably is the plug gap being a bit big not helping it. Curious to see the injector swap run. Definitely help with the cooked bottom end issues that these Polaris sleds have.

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Spaarky

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What's your pipe to boost pressure comparison? I have heard that sled has some pipe mods. Possible it's too far?
 

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The turbo is by far the biggest restriction in it. It's got a 2.25 stinger in it. Never ran pressure sensor in the pipe. Possibly next year I can. Make no mistake, this sled hauls the mail like crazy. Just was a bit picky at first. It runs really good now.

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TRS

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The turbo is by far the biggest restriction in it. It's got a 2.25 stinger in it. Never ran pressure sensor in the pipe. Possibly next year I can. Make no mistake, this sled hauls the mail like crazy. Just was a bit picky at first. It runs really good now.

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Pipe pressure is an eye opener for sure. I ran a gauge on the dash from the center section of the pipe during modifications to the BD kit . Settled with the 2" pipe stinger. Upsizing the downpipe helped also. Ran awesome so I quit there. 2.25" stinger may get the nod for a "test next year".
Justin, there you go, you have been wondering about the move up.
 

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I should have mentioned the 2871 for a turbo in mine. Got a smoking deal on a forced performance 2871 HTA I couldn't pass up. Full 3" down pipe on mine....will get redone with a muffler setup for next year. Got put together last minute and never changed it. Also running the external waste gate off the center section of the pipe.

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Spaarky

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The reason I was wondering was this sled. Heard it was a gorilla. There is no question the 2871 makes BIG power, but what about in the trees? I would give up top end for throttle response.

Sorry if this is getting drug another direction AGAIN.
 

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It doesn't seem to me to be laggy in the trees. Tight spots it's right there. I need to learn how to ride it to take advantage of it. I guess I would need to get on a stock silber or sidekick sled to compare. The axys on boost is also completely different from a pro on boost in my experience with the 2.

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mountainhorse

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Connectors and pins are easily available for this... on both ends of the injector harness.

I think that a rising rate FPR could prove to be a bit unruly and not consistent with a "stock as possible" goal for this N.A. sled.

I am a fan of a more precise FPR than the inexpensive Seimens 'tophat' mini FPR that comes built into the stock PFA.

Lots of factors to play with... Maybe the PC-5 with timing control would come in handy??


Definitely prefer to keep as many stock parts and settings as possible.
With that said, a fuel controller may be needed. Also looking at a larger set of injectors which will force an injector harness build. Darn epoxy.
Thoughts of an external FPR, maybe a rising rate with the signal from the pipe.
Going to install this on my '12 LR. The Dyno will come into play for testing this summer.
A timing key may also come into play.........
 
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Spaarky

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It doesn't seem to me to be laggy in the trees. Tight spots it's right there. I need to learn how to ride it to take advantage of it. I guess I would need to get on a stock silber or sidekick sled to compare. The axys on boost is also completely different from a pro on boost in my experience with the 2.

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Eventhough it's a Pro, you need to compare it to Tony's turbo. His set up is very impressive.

I might pic up another Pro to mess with some changes. Plus I want one with Tony's chassis set up.
 

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Eventhough it's a Pro, you need to compare it to Tony's turbo. His set up is very impressive.

I might pic up another Pro to mess with some changes. Plus I want one with Tony's chassis set up.
I'll get a new thread going at some point with all my sled in there. I like his pro setup, played with that stuff last year and it works good. If it wasn't for the exhaust valve changes to the 800 in the axys I'd still be riding the pro. But the valve setup is a huge change to that engine.

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I wish there was a section on this forum that only had technical threads like this. No "what oil do you use" type threads. Although some of that definitely has its place for technical discussion. Topics like this one seem to be left to the few people that still like to experiment with things other than what the manufacturers put out.

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Random thought....is the injector timing as crucial as it seems when the injector gets moved back? I know it's not a long distance change, but if you're fogging the bottom end aren't we mainly looking at fuel volume in the engine vs correct injection timing? Is swapping the injectors needed really? If it is and you can just swap the harness from one to the other, it's easy.

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TRS

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Random thought....is the injector timing as crucial as it seems when the injector gets moved back? I know it's not a long distance change, but if you're fogging the bottom end aren't we mainly looking at fuel volume in the engine vs correct injection timing? Is swapping the injectors needed really? If it is and you can just swap the harness from one to the other, it's easy.

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They are easy to swap.
We had an '11, in the shop, that was having drivability issues from mid to top end. We found the injectors were reversed during a rebuild. Once we corrected the injector location all was good.
I believe we will get better atomization with injectors firing during intake vacuum/compression stroke than flooding the reed during the power stroke.
Time will tell. Auxiliary injectors, on many turbo kits, are far from the reed cage and fog the intake with good result.
AC and BRPs new 850 are locating injectors in the throttle bodies, I believe is a good choice.
I tried to re rack a set of cat throttle bodies for this app. I shelved it.
 

gopher-it!

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flanges

Going to move the injectors from the cylinder to the intake for testing.
I used a Silber turbo intake manifold and installed injector bosses to the top of the flange. A new fuel rail will be in order that will allow the use of the dampers and the stock fuel lines.
I'll plug the lower injector bosses on the Silber manifold along with those in the cylinder.
I'll switch the injectors to fire on the compression stroke.

Very similar to the set up I use on my cfi1000.
Flanges are separate and a one piece fuel and injector rail
mounted on top. Built by Brad at PAR. It's nice to have lubed up reeds again.
 
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