CX-7 Turbo smaller than MS6

cdesigns

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Mazda CX-7
I was just watching this youtube video from mazda, and they tell the specs of the turbo and differences from CX-7 and MS6 and the cx-7 turbo haves a smaller turbine A/R on the hot side and cold side , compared to the MS6.

:( But, I can get a used MS6 turbo and upgrade mine easily.

http://www.youtube.com/watch?v=R3D5Tm40T4I
 
Yeah they made it smaller so it would spool faster and offer more low end torque, so you can but without major mods like a downpipe FMIC etc you will lose some low end for a few more in the top end.
 
Another thing I saw is that we have high pressure fuel , instead of 40psi to 60psi we have like 400psi?????? at least thats what I heard from the video.

I just bought a electrical fuel gauge 0-100psi , I haven't installed yet now I don't know if I can.
 
They do run high Fuel pressure..I do know that is one of the things with the disi setup. I dont think its pressurized to the pressure until it goes through a second pump of some sort.....ITs not 400psi right out of the tank.
 
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They do run high Fuel pressure..I do know that is one of the things with the disi setup. I dont think its pressurized to the pressure until it goes through a second pump of some sort.....ITs not 400psi right out of the tank.


So the 0-100 electric fuel gauge is worthless? :(

I have both:

BOOST and FUEL gauge electric. I think they're going to hit ebay today :(
 
No no..Do some research..I am going by my limited reading and memory on this.

But why do you want a Fuel pressure gauge anyway..you would have been much better off spending that money on something else.
I know those gauges arent cheap.
 
No no..Do some research..I am going by my limited reading and memory on this.

But why do you want a Fuel pressure gauge anyway..you would have been much better off spending that money on something else.
I know those gauges arent cheap.


Well I though I could boost the cx-7 more and watch the fuel pressure and maybe add a little more fuel like my old turbo car, but this DISI is kinda tricky I guess. I'm going to sell my gauges and buy a BOV or Intake.
 
DI in cylinder injection pressure varies from ~ 400 psig to ~1600 psig. This is quoted for a CX7
 
pressure at its high point is around 1600 psi. i know this, cuz when i was on my 3rd fuel pump replacement, lol, i started to ask questions. mine was failing, squirting out around 70 (possible reason for my detonation) but never determined to be the culprit
 
one thing that was not mentioned in that vid are the heads.

ive heard the heads flow tremendously well for stock OE heads and bergenholtz (drag racer) uses stock heads for his race car.
 
Direct Fuel Injection involves spraying fuel directly into the combustion chamber while the piston is coming up for maximum atomization and distribution. Diesel engines have been using this type for decades.

Usually fuel pumps merely pump gas from the tank to the carb or to the fuel injection head located in or above the intake which must only over come the pressure present there. With turbo cars this may get to to 20 psi but still nothing compared to peak pressures in a combustion chamber.

Hence, there are usually high pressure injection units in the injectors located on the heads at each cylinder to boost the pressure to the high amount needed to overcome cylinder pressure. I cannot find out if this is how Mazda does in on the CX7. I cannot see them having lines with that pressure running round a car. Normally they use a normal pump to push the gas to the injector heads and they pump it into the head under extremely high pressure.


http://static.howstuffworks.com/gif/cmsimages/articles/2006_Articles/cx_7/CX-7.wmv

Interesting graphic video of the engine.
 
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There is an in-tank fuel pump, like all cars and a cam driven unit in the engine bay that drives the high pressure. The speed 3 & 6 guys are looking for a solution to upgrade the cam driven pump, so that they can push higher HP...
 
I've got a spare K04 off an MS6 for sale if anyone is interested. I had planned on having it clipped and ported to replace my stock turbo, but have decided to go much bigger and no longer need it. $250 shipped anywhere in the US.
 
I've got a spare K04 off an MS6 for sale if anyone is interested. I had planned on having it clipped and ported to replace my stock turbo, but have decided to go much bigger and no longer need it. $250 shipped anywhere in the US.

That is so tempting but my wife would seriously kill me if I bought that. LOL
 
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