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Well as the snowmobiling season is getting wrapped up in central mn, it’s time for the fixing and modding to begin! I have a 95 rxl engine with carbs currently. This summer I want to convert it back to efi. Buttt I want to make it a lot better with more power. So.....
  • aftermarket ecu (thinking fuel tech ft 450)
  • bigger injectors
  • more sensors!!!! (MAF, MAP, EGT, CPSthere’s more I’m forgetting)
  • maybe knock sensor??
  • adjustable fuel pressure regulator
Now for spark.... i was thinking of going to smart coils? So ditch the cdi and have just smart coils!? What’s yalls thought on this...
-I would need a trigger wheel
Then for more powa..... TURBO!!!!!
yes sir ya heard that correct.
-have custom single pipe made?
-Obviously oil cooler
-oil pump ran off battery
-custom air box
-boost pressure regulator (I want max 10psi)
My goal is to make it a reliable engine. With this ecu you can make up to 5 different maps.... eco, standard, and sport mode?? Kinda like what the ace models have but go with different fuel amounts and levels of boost instead. I know I’m not thinking of everything I wrote down... but what’s your guys thoughts or input on this?
 

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Sorry to bust your bubble, but about the only thing that might help is the adjustable fuel pressure regulator.
With the time and money you will have to put into it you would still be way better off with a Stock F7!
 

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Yeah but the XCR 800s had crankcase issues. I asked dan about those doesn't matter if it is a triple or the liberty twin they just won't hold up.
 

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crankcase issues on XCR 800's? never ever heard of that. I wouldn't hesitate to buy one; a 99 red rocket. That would easily beat a $10k RXL.
 

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Yep I asked Dan about it a couple weeks ago as I was looking at a 2003 and he said don't. Said all of them had issues with the crankcases. He would know on those 800s.

And I quote "All of the big block 800's have issues with the crankcase being too porous and with the HP of the 800, the crankshaft bearings, especially the PTO side, beat on the case and make it out of round. It gets bad enough that the crank breaks. The reputation of the engine is that it has bad cranks, but it's not the crank; it's the case. The problem can be aided by adding a bigger bearing to the PTO side to spread out the force.I also put in a torque stop and an engine stop and also an engine plate to try to keep the engine planted. Keeping the clutch balanced helps about as much as anything else can. The problem is worse in the mountain sleds, as the power is on and off a lot when climbing, and the track puts a lot more stress to the drive train because of the track depth and length."
 

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The Fuji 800 triple is a completely different animal than the Polaris twin. The 800 Fuji triple was a powerhouse and didn't have the reputation for the crankcase issues the Liberty twin has. Their big issue for the mountain guys is weight, if you can get close to the same power out of a lighter engine, that's what guys go for. Polaris quit using the 800 triple when they quit using Fuji powerplants and started making their own engines.

Adding HP to any engine will probably decrease the life of the engine, you have to pay to play.

As far as the Liberty 800, there are places that have pretty much made them bullet proof... Indy Specialties comes to mind. Back in the day of all the problem 800's, you could get an Indy Specialty engine from Indy Dan and it would come with a 3 year warranty, regardless of how you used it, as long as you didn't use synthetic oil. Indy Dan was a firm believer in the superior coating of regular oil!
 
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