MRD Fuel injected Engine

Quinc

Quinc

Buy a Superjet
Location
California
Saw this on facebook and thought it was cool.

"A piece of rare race history...complete MRD race motor...4mil stroker...MRD head with 4mil spacer plate...MRD fuel injection also a second injection setup... as you can see in the pics hasn't been ran... has yamaha case with MRD modified reedcage area swapped to.a kawasaki 750 (bigger reed cages)...making this a yamasaki lots of portwork done on this...and it lives my living room..."

@holeshot @Nuklear6 @waxhead @tntsuperjet Too bad the buzzard is banned. He would probably know who built it and who ran one in what races.

12548835_1543083519343527_2673269933595787333_n.jpg

12400482_1543083559343523_3865972355344911427_n.jpg

12541132_1543083606010185_5765893169311327132_n.jpg

12573801_1543083632676849_4988236768749057285_n.jpg

12509828_1543083652676847_8297706133684386678_n.jpg

12523079_1543083686010177_6045954170480414536_n.jpg

12494871_1543083669343512_655987164939498208_n.jpg
 
ISeeWetPeople

ISeeWetPeople

Location
Finland
What is it with injections why there is so few of them? Whybdont they work? Reason im asking is that my friend is building a injection 5mm stroker sj engine with 89 pistons and im not sure is he gonna pull it off.. and he is after for freestyle engine
 
tntsuperjet

tntsuperjet

Tntperformance-engineering.com
Location
Georgetown ca
That is the same setup I ran in my practice ski.
My race ski had 6m but everything was identical.
Ran that setup all of 93 and 94 every tour round
 
tntsuperjet

tntsuperjet

Tntperformance-engineering.com
Location
Georgetown ca
Dave Harriman, Dan Fitzgerald, Kris hynrich,
All built motors with that setup in 94-97
Is there a letter and number engraved into front of the Cyl?
 
SKI BONEZ

SKI BONEZ

SKI -BONEZ
Its my motor in the first pic... and my friend dominics in the second pic... i havnt ran the mrd 4 mil that im selling but i did ride kevin persables (i think i spelled that right lol) i rode his old mrd race boat and the fuel injection when tune and set up right...blows all carbs out of the water...the response is insane even compared to 49 full specs...but you need a good tuner that knows fuel injection robert sand tunes these and many other motors too...he also sells all the replacement parts for the mrd injection
 
SKI BONEZ

SKI BONEZ

SKI -BONEZ
tntsuperjet said:
Dave Harriman, Dan Fitzgerald, Kris hynrich,
All built motors with that setup in 94-97
Is there a letter and number engraved into front of the Cyl?
Click to expand...

I dont see any engraving on cylinder...i did find a 4 2 punched into the cylinder above one exhaust port...but i dont remember if a 61x cylinder has that normally or not...lol
 
SKI BONEZ

SKI BONEZ

SKI -BONEZ
ISeeWetPeople said:
What is it with injections why there is so few of them? Whybdont they work? Reason im asking is that my friend is building a injection 5mm stroker sj engine with 89 pistons and im not sure is he gonna pull it off.. and he is after for freestyle engine
Click to expand...


The main reason the fuel injection isnt used much is tuning... most people wanna set it up and beat it till the motor blows...lol from my experience is takes some tuning but robert sand says he can dial the mrd injection in perfectly... :) also i know that full spectrum is working on a fuel injection setup... a carburetor will never out perform fuel injection as long as fuel injection is done and tuned right...just like cars today but it isnt easy...lol
 
tntsuperjet

tntsuperjet

Tntperformance-engineering.com
Location
Georgetown ca
The mrd is very simple and easy to tune. It has really good throttle response.
Can run it on free ride without a scavenge tank as you suck just a touch of air. Boat dies. It won't recover like pulse carb pump will.
It airlock and hard to prime compared to pulse diaphram pump.
There is no carb that can match the throttle response of forced fuel delivery.
With a carb you open a butterfly and let air into the motor. Then the vacuum signal goes up and then it pulls fuel in. So fuel is always behind the air and there always a lean condition before it gets its fuel. This causes a delay in power.
So if you spray fuel in with the air you can let more air in faster and get more response.
So you can go to much larger throttle plates because you don't need the air speed in a Venturi to bring the fuel in.
52-55mm throttle plates can be used with no draw backs other the. Which one can you have enough throttle control to ride
 
rhugo21

rhugo21

Location
Hermosa Beach, CA
tntsuperjet said:
The mrd is very simple and easy to tune. It has really good throttle response.
Can run it on free ride without a scavenge tank as you suck just a touch of air. Boat dies. It won't recover like pulse carb pump will.
It airlock and hard to prime compared to pulse diaphram pump.
There is no carb that can match the throttle response of forced fuel delivery.
With a carb you open a butterfly and let air into the motor. Then the vacuum signal goes up and then it pulls fuel in. So fuel is always behind the air and there always a lean condition before it gets its fuel. This causes a delay in power.
So if you spray fuel in with the air you can let more air in faster and get more response.
So you can go to much larger throttle plates because you don't need the air speed in a Venturi to bring the fuel in.
52-55mm throttle plates can be used with no draw backs other the. Which one can you have enough throttle control to ride
Click to expand...

@schicks


Sent from my iPhone using Tapatalk
 
upstand

upstand

tntsuperjet said:
The mrd is very simple and easy to tune. It has really good throttle response.
Can run it on free ride without a scavenge tank as you suck just a touch of air. Boat dies. It won't recover like pulse carb pump will.
It airlock and hard to prime compared to pulse diaphram pump.
There is no carb that can match the throttle response of forced fuel delivery.
With a carb you open a butterfly and let air into the motor. Then the vacuum signal goes up and then it pulls fuel in. So fuel is always behind the air and there always a lean condition before it gets its fuel. This causes a delay in power.
So if you spray fuel in with the air you can let more air in faster and get more response.
So you can go to much larger throttle plates because you don't need the air speed in a Venturi to bring the fuel in.
52-55mm throttle plates can be used with no draw backs other the. Which one can you have enough throttle control to ride
Click to expand...
Yep, a seperate scavange tank is how they drove mechanical fuel injection on cars. But you have all but figured out the cure on freeriding with a MRD. Let me give you a hint.
 

Attachments

  • mrd with mikuni (1).pdf
    153 KB · Views: 157
You must log in or register to reply here.
Top Bottom