just bought a mrd fuel injection for my superjet might need some help

[jetski9010]

well I bought the mrd fuel injection kit off ebay today for $400 I just couldnt pass it up. I was wondering if anyone out there has any tricks or tips for tunning these things. I am setting it up on my superjet for freestyle. Thanks for the help.

 

[Kaveman]

Might try shooting Prem1x a pm. He had one on a blaster a couple of years ago.

 

[Prem1x]

Be sure to read all the info in this thread before pinging me MRD Mechanical Fuel Injection. after that I will be glad to help.

 

[jetski9010]

thanks for the info about the threads

 

[jetski9010]

I am just now getting around to trying to put this thing on. I started reading back into info on this system. I have some pics of all that I have and I think I have all the parts here. I keep reading all these stories about bad pop off valves and gears and stuff is it better just to start fresh with new valves and gears and all or sould I just bolt on what I got and try it. My superjet is also bored to a 760 so I am guessing that is going to mess with tunning a bet. I talked to a few shops that are local and two of them said they could set this system up for me. Does anyone think I am better off just dropping my ski off at a shop during the week and having someone eles tuning it for me so I can just be done with it or is this system really not that hard to tune once you get the hang of it?

 

[jetski9010]

pics

 

[snowxr]

If your local shop has experience with MRD I would drop it off. If they haven't installed and tuned them in the past you're better off doing it yourself. These systems are great for racing, but you probably will have a tough time making it perform well for freestyle.

 

[jetski9010]

I also was going to ask about filter socks for the filters. I know these things set low in the hull and some people say that could be a big problem. I think I have seen these same ocean pro vortex spark arresters on some sit downs with filter socks on them. Does anyone know what size they are and if anyone sells them?

 

[Talsivar]

mrd is a horrible setup for freestyle. great for going fast though. air intake sits way too low in the hull sucks in lots of water. it also doesn't like rough water or extreme movements.

 

[masterblaster]

I think mrd rips for freestyle,the intakes do sit to low in the hull,but you can get covers for them outerwear makes them for the ocean pro intakes,few things you can do to help are,run foam in the gas tank,use the groupk air separator,cut turf for inside the ski and dont glue it down,it floats and keeps the splash down,run twin 550 bilges and run them while you ride,or a good scupper.
Mrd hits harder than anything else ive tried,you will find some that have had issues with having to retune and others who have had no problems with it for yrs.I believe the ones who are having constant trouble had worn pop off valves or fuel pumps or were at the very edge of proper jetting to start with. Im working with a machinist to come up with a intake riser for the mrd so that the filters will sit as high as the stock intake.trust me nothing hits harder right off idle.

 

[Talsivar]

i ran it for about a year. the foam in the tank and other things you suggested sound like a good idea to fix the rough water problems. i never had any tuning issues and it did hit hard but the water ingestion cost me a few rebuilds. and it sucked gas like crazy. i guess it depends where you ride, when i lose my ski in the surf and have to swim for it usually by the time i get to it it's pretty full of water. with the intake sitting that low outerwears or not the engine is flooded. through lots of trial and error i've come to the belief that simpler is better, i spend more time riding that way. it will be interesting to see what you think of it once you get it installed and run it for awhile.

 

[masterblaster]

If I am successful at getting a bolt on piece of billet to raise the intakes high as carbs,it will be a great freeride setup,it does use alot of fuel,but so do dual 48s and those still dont hit as hard as the mrd. sj skis in the surf if they get upside down,they are water fouled and wont restart,mostly cause aftermarket hoods and crapy breathers and scuppers,along with baffelless water boxes allowing water to flow back into the motor. so even raising the intakes wont help with that on mrd,the point is to keep small bits of water from splashing into the intakes while ridding.the higher the better.small performance loss going away from the straight in air intake,but worth it for surf ridding.

Getting water in your motor from being flipped over in surf is not going to cause damage,we have sunk so many skis its not funny,never poped a motor,just get them running turning them upside down on the beach and back in the water 10 min later is the key to that.we ride 5 min on any sunk ski before its trailered

 

[Talsivar]

well with your improvements and raised intake it might just make me change my opinion on the mrd. i'd like to see some pictures if you get the intake raised.

 

[jetski9010]

I think mrd rips for freestyle,the intakes do sit to low in the hull,but you can get covers for them outerwear makes them for the ocean pro intakes,few things you can do to help are,run foam in the gas tank,use the groupk air separator,cut turf for inside the ski and dont glue it down,it floats and keeps the splash down,run twin 550 bilges and run them while you ride,or a good scupper.
Mrd hits harder than anything else ive tried,you will find some that have had issues with having to retune and others who have had no problems with it for yrs.I believe the ones who are having constant trouble had worn pop off valves or fuel pumps or were at the very edge of proper jetting to start with. Im working with a machinist to come up with a intake riser for the mrd so that the filters will sit as high as the stock intake.trust me nothing hits harder right off idle.

Thats what I wanted to hear. I think I am not going to mess around with tuning this system and just take it to the ski clinic and have them dial it in for me. I did already get the group k air fuel seperator do you also need to run foam in the tank too? I will have to hunt down a set of those outerwears too.

 

[jetx]

http://www.outerwearsracing.com/index.asp

 

[jetski9010]

http://www.outerwearsracing.com/index.asp

Thanks for the link

 

[masterblaster]

Thats what I wanted to hear. I think I am not going to mess around with tuning this system and just take it to the ski clinic and have them dial it in for me. I did already get the group k air fuel seperator do you also need to run foam in the tank too? I will have to hunt down a set of those outerwears too.

it might not be necessary to do along with the air sep but its a very cheap fix to help in keeping the air out of the line to start with

 

[jetski9010]

it might not be necessary to do along with the air sep but its a very cheap fix to help in keeping the air out of the line to start with

But filling your tank with foam, wouldnt that make even less room for fuel and cutting your runtime even shorter? I am going to try to stay away from it if I can. I got some outerwears on the way too.

 

[jetski9010]

Got the group k air seperator today. How do you guys rig this into your mrd kit? Does it go between the fuel pump and the carbs or does it some how go before the fuel pump and you use another pulse fuel pump to push the fuel thorugh the seperator?