Would this fuel pump be fine to use with a 12a turbo application? 43gph is 163lph at 85psi. http://www.summitracing.com/parts/SUM-G3138/ im not making huge power, maybe 250 - 300hp, looking for cheap. lol

 

I'm not saying yes or no, just passing on info. The GSL-SE has the largest fuel lines and highest output pump of any of the FI 7s, including TIIs and FDs. The normal upgrade for the TII is a Walbro 255 lph. I don't remember the specs on the stock SE pump but it's near the Walbro, iirc. If you can find the SE fuel lines and an external Walbro you should be good.

Here's Summit's list of Walbro external pumps. Fuel supply is not the place to go cheap, especially with turbo charging.

http://www.summitracing.com/search/b.../?autoview=SKU

 

163lph(which is it's max rated output) won't get you to 300.

when fuel is concerned you should go bigger, not borderline. not sure what the 1st gen turbo guys do for fuel but an in tank pump is cheaper, especially if you were to buy a used FD pump for about $30-50 and pushes about the same as that pump does, or a walbro for $100 which is good for over 400WHP.

 

for 250 to 300 horsepower id have to go with bigger fuel lines? Ive never heard that before, realisticly 250 will be max for quite awhile. if i go with the walbro 255lph and stock fuel lines, will that get me to 250?

 

The stock FC fuel lines for the 146 hp NA are larger than the 12A fuel lines. On the other hand, the SE fuel lines are bigger than the TII. It cost me 20 bucks for a roll of 3/8" aluminum tubing to redo the supply and return lines in the widebody. You will need a tubing bender and flaring tool. Remove the oem lines and use them as a pattern.

The Walbro will get you well past 250 hp.

 

what about the lines actually going into the tank, those will also need replaced too right? or just from the pump to the carb.

 

I think you guys are forgetting that as pressure decreases flow increases.... I will be running the MSD version of this pump in my blowthrough build with 3/8 feed and 5/16 return, and I'm pretty confident it should be enough. The OP didn't mention if he was running EFI or blowthrough. A blowthrough set-up making 15 psi of boost would need a max pressure of 3-4 base and 15 to overcome pressure in the float bowl, which would be between 18 and 19 psi of fuel pressure. I would think this pump should flow plenty for those requirements. I mean it's 163 lph at 85 psi.... while flow rate isn't exactly linear and without knowing the slope it will be tough to know exactly what it will flow, worst case scenario if we say a reduction in pressure of nearly 400% is only equal to an increase in flow of 50%, we are still at 244 lph which as we stated above is enough to get you over 250hp. Also, if you still need more flow you can install a Kenne-Bell Boost a Pump and increase flow substantialy. As long as you have a properly sized bypass you shouldn;t have any issues with pump life. Here's a little info on how voltage can affect flow rate on a pump.

http://www.stealth316.com/2-fuelpumpguide.htm#j5

So make sure you have good consistent voltage and current feeding your pump for maximum performance.

 

^ so your saying that the summit pump will be fine for my 250hp? and yes its a blowthrough setup, not EFI. I take it i need to atleast up my feed line to 3/8? What about return and what do I do about the line going from the pump to the tank? How do i increase that size? From the pump to the carb will be easy, but i dont know about from the tank to the pump.

 

Personally I don't see any reason why it won't work.... A heavily built turbo rotary should have a BSFC (brake specific fuel consumption0 of around .60 which is similar to a turbo'd V8 and there are guys running these pumps in Holley blowthrough set-ups on some of the Turbo V8 forums, keep in mind Holley's require around 6 psi of base pressure compared to the 3-4 of a weber style carb.

The lines are another story... you'll need to drop the tank and run a new(bigger) pick up line in place of the return and use the old pick up as the new return. I think SgtStinkFist posted a pretty good picture of how he modded his pick ups.

 

It is cheaper, but there are several reasons many Turbo FB's run external pump.
1) The stock pump is external already, including the wiring and lines.
2) You can't access the inside of an FB tank without draining/dropping the tank off the car (a real PITA).
3) Only the GSL-SE Fuel Tank has an access port on the tank, but you still have to drop the tank to reach it.
4) Regular FB's would need to have the tank cut and/or welded to make an access port or baffles inside the tank.
5)FC's and FD's can reach the inside of the tank/pump through access panels in the car - making it MUCH easier to make changes.

With this in mind, I just rather have easy access to the pump in case I need it. I don't want to have to drop the tank ever again to access it. Although in an FC/FD - I definitely would have gone in-tank.

Mind you - some members have done some custom in-tank stuff in the FB's that is absolutely beautiful - but they still would have to drain/drop the tank to make any changes.

 

This.

That pump should be plenty.

 

wow, thank you guys so much. I really appreciate it!

 

Check out my pics... i have a walbro 255lph pump and mallory rising rate regulator. i rean 3/8 line all the way for supply and return.. the stock return was not big enough and the lowest pressure i could get was about 6-8 until i increased the return line. if this is the case you will have to modify the sending unit. I dropped the tank and removed the sending unit. took about 20 mins. then cut off snd drilled out the old lines, rebent the 3/8 ones and reused the stock strainer.. then welded the new lines in and siliconed the welds to make sure. works great so for with 8 lbs boost should be more than enough for 15 psi and aroung 400 rwhp next year..

 

Directfreak, could you explain this comment? The SE and carbed S3 tanks are identical except for the fuel pickup assemblies and the sump cup in the SE tank. What access port are you referring to?

For the tank to pump lines, replace the carbed fuel pickup with the SE one, it's much larger. If you spend time in the 2nd gen forum, one of the first TII mods is increasing the fuel supply, almost always with the Walbro 225 lph pump. It's a 'better safe than sorry' mod. You blow your engine from running lean and detonating, that extra 50 bucks for the 'safer' fuel pump will look like peanuts.

 

http://intertron.com/ron/tank.html

I definitely know that the S1 and S2 Series
FB do not have the Removable top section
with the fuel pick-up,return lines and vent of the GSL-SE.

I could have sworn I just a post with pics of two tanks side by
side....

However, I don't think we ever confirmed if the S3
12A powered cars also had the same style pickups, because I
am pretty sure they don't have the fuel injection baffles in the tank
either.

I will look into it.

 

this is my modified sending unit with 3/8 lines feed and return from my 85 gs 12a. not sure if its and s3 i dont know what all the s's stand for... what years or what not. let me know if this helps

 

Series 3 are 84/85 models.

And based on what you are showing, - I guess Scott is correct.
All S3's have the removable top section.

 

I have a thread in the archives that shows the differences between the 12A/FI S3 tanks. S3 is when Mazda started the removable fuel pickups. The SE tank has larger tubing and a sump cup, everything else is the same.

https://www.rx7club.com/1st-gen-archive-71/fuel-interchangeability-fuel-tanks-facts-604917/

S3, the S stand for Series. S3 is the 84/85 models.

Guess I took too long to post this one, lol.

 

i like to sump the stock tank and use a mallory 140 pump.it is over kill. but you never no when you are going to need more fuel.

 

niCe! You weld on your own sump? I did that for my buddies mustang.... well its a Capri.. Hes running 1/2 aluminum lines!

 

thanks man. a am learning as i go

 

same here i like doing everything my self tho even if it means failing a couple times here and there haha well most everything