By returnless it is meant that no return line from the fuel rail to the tank exists.
Swoope------agggghhhhhhh! Cost me 10bucks! He was a good e bayer--it was at my home 3 days after paypaling.
Dannobre-- I think that Mazsports system is much more of a return system than the oems--because Scott said his system coverts it over to a return line system. See his post.
Like that system you have.
olddragger

 

No return line on either that I could see Would need upgraded fuel rails to do a true returnless system

 

or the last several months we have been testing and are now proud to release our fuel system upgrade for the RX-8. The stock fuel pump appears adequate for moderate performance increases we have witnessed failures such as locked up and dragging pumps which have led to internal engine damage.
In a rotary equipped vehicle, reliable, consistant fuel pressure and flow are extremly important and this system was designed to support 400+ rwhp using tried and true components from years of our RX-7 development. We have incorperated a rising rate fuel pressure regulator and have converted the system over to function as return line system which also has eliminated some fuel slosh issues. The factory fuel pump carrier assembly is removed, ours is installed as a unit then the factory fuel line and electrical connections are reattached making this a truly plug and play system. For more information check it out on our website Mazsport.net
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Dannobre this is the post by Scott concerning his system and him saying he converted it over to a return type. You dont have to change the fuel rails to do this.
OD

 

that's intended for higher HP applications where adequate fuel flow is required, not for lateral load suction issues

 

true--read my earier post.
OD

 

Well my gage showed half way between 1/4 and 1/2.

It was the last lap before cool down.

After running out of fuel I went to the pit.

After ten minutes the gage dropped to 1/8th.

On the fastest track in the West my fuel starvation problem was at 1/8th of a tank.

I talked with Kelly, and she said she ran out of fuel twice at around 1/4 tank.

That's the lastest feed back we have on this issue.

https://www.rx8club.com/rx-8-racing-25/willow-springs-136459/

 

you still with the original pump?????



beers

 

Yes, we both have the orginal pump.

I'm just surprised the gage was so off.

Now that I think of it.. scientifically speaking the centrifigal force kept the gage up so it couldn't drop and show the accurate reading.

The track is a momentum track where you really don't have to use your brakes except two or three times. (if your good or brave)

A spec mita got a 1:36 on the 2.5 mile course.

Man must have been one hell of a roller coaster ride. Full speed all the way around Yee Haw!

 

the pump is on its 5th version.. i dont know of anyone that has reported on how it does on the track.

but for the price it is cheap insurance... 135 bucks.

beers

 

i have the same problem as OP, new pump (oem) and below 3/4 it starves on 180° turns