Fuel pump/tank question
 

Has anyone here ever used an in tank style fuel pump on a stock fuel tank? I want to use a walbro style in tank fuel pump on my stock gas tank.

Here's how I did mine:

1987 FC S4 RX-7 TII fuel pump and hanger assembly in 84 tank
Attachment 658180

Welding on the mounting ring
Attachment 658181

So you cut out the hanger mount and sump from an FC and welded it into a 1st gen tank?

A lot of us have gone this route, you sacrifice an FC tank for the mounting ring, sump cup, and hanger.

Attachment 658129

Attachment 658130

Attachment 658131

Thanks! Both of your pictures are a huge help!

how is your drag project coming along?

whats wrong with an external fuel pump?

The drag project is moving along slowly. But slow progress is better than no progress.

And there is nothing wrong with inline pumps. I actually prefer them. But I already have a brand new in tank walbro 400 fuel pump. I have 90% of the parts to turbo my 12a sitting in my garage. I'm attempting to get it done without spending a dollar.

I was all set to post pics of my setup but those guys beat me to it, just like them I sacrificed a FC tank for the mounting ring and slosh cup. FWIW the S4 pump hanger is the correct height for an FB tank and requires no mods to use (once the mounting ring and cup are welded in of course) the S5 is too tall and will need to be shortened slightly.

resurrection, i know ... but i didn't think my question warranted a NEW thread.

basically, i wanted to know if there was anything "special" that goes into designing a slosh cup. i am doing an in-tank pump setup with my spare tank from the '84 and pretty much just need a slosh cup and pump now.

so basically, i want to know design (orientation of the hole, would i benefit from more than one, etc.) and also the dimensions, if anyone has them to share.

thanks.

The gas tank is out of my 83 S right now since I'm doing some rust repair on the car. When I get home I can measure the FC slosh cup that's in there. It works really well so I'd just copy that if I were you :)

seems like perfect timing for me. thanks, man. :) i appreciate the help whenever you get to it.

A question for those that have done this....are you still using the first gen fuel level sending unit or are you using the one on the s4 hanger assembly?

Subscribed.

Not sure when I'll get to mine, but I wanted to do a rotary vane MAP/PWM controlled pump that hasn't reach the market yet and use a Holley Hydramat instead of a pickup bucket. As for the mounting flange, I'm sure a universal 8" could be used with a bit of coaxing.

Does the slosh cup get tack welds to hold it in place?

subscribing. so it needs to be an S4 tank but does it need to be a TII?

editing so i don't look so dumb...i don't believe mazda would have made 2 different tanks (an NA versus TII) but instead, used different pumps based on the application. would still like to know how to secure the slosh cup though.

Not sure if there are 2 different pumps but i can say that the s4 tank i just cut apart had the slosh cup tack welded to the bottom. Im going to drill them out and tack the cup back down to my gsl tank.....