Druken

Currently I'm doing a S5 n/a 13b swap into a 79' and I've gotten everything pretty much down, except for the fuel pump. I've read a couple manuals for both S5 and SA models in how to get to/remove/replace the fuel pump. It doesnt make any sense to me, but I was thinking of giving it another shot tomarrow or the next day depending on how fast of a help I get here. Basically the two fuel pumps are completely different, one is suppose to be in the gas tank and the other is outside of it. How am I suppose to do this swap? I would have perfered keeping the stock SA pump but I've been reading in the forums that it wouldn't provide enough for the newer engine. So for those who have done this or know how to, please enlighten me. Is there a bunch of other parts that I need to purchase or is the S5 fuel pump all I need, spent a lot of money on the car already and would perfer to keep this on the cheaper side.
ps. Please break it down, I get easily confused when given vague directions.
pss. Thanks in advance.

IanS

iTrader: (4)

Are you keeping it fuel injected?

Druken

Yeah I am keeping it fuel injected.

trochoid

iTrader: (6)

You have 2 options. 1, install a Walbro 255lph external, with a surge tank, 2, Gut a 2nd gen tank for the pickup/pump holder and install it in your SA tank, along with the sump cup. This works on the later tanks. I don't know if the SA tanks are tall enough. You need an internal depth of 10" for the FC pickup, but they can be shortened by maybe 1-1/2".

Rx-7Doctor

iTrader: (13)

Seems the easiest route would be to use a Se fuel tank and either the Se fuel pump or the Walbro one. Also remember to install an inline FI fuel filter also.

trochoid

iTrader: (6)

Unfortunately he has an SA and the later tank won't fit without removing the spare tire well. I think 13BEEF has a good pic of his external setup. Thanks for the reminder on the filter Doc, I forgot that part.

Rx-7Doctor

iTrader: (13)

Trochoid, thanks for the reminder of the Sa tank. I forgot about that full sized spare tire.

trochoid

iTrader: (6)

Us old guys have to stick together to keep on top of our lagging memory. lol

Rx-7Doctor

iTrader: (13)

You got that straight. I once bought a book on how to improve your memory, unfortuneately I can't find it, LOL.

82transam

iTrader: (18)

Read this:

https://www.rx7club.com/1st-generation-specific-1979-1985-18/efi-prepping-1st-gen-577867/

All your questions will be answered That is definatly the way I'm going with my 13bt swap, when I get to that point that is.....

Druken

That write-up was great, but I doubt I'll be able to do that with the limited amount of tools and time I'm given to work on the car, due to school and work. Maybe as my last resort.

But I was looking into the Walbro 255lph fuel pump and it seems like a good idea for my current situation. I wanted to ask questions to make sure of things before moving forward with the purchase. This pump will be a direct bolt-up part replacing my stock pump? Do you know a place in which sells them for cheap? And where can I get the surge tank?
Thanks for the help.

REVHED

This is my fuel setup. It uses a Carter filler pump and a Bosch EFI pump. The surge tank is specifically made to fit the 1st gen. frame rail. You can get one like it at http://www.tweakit.net/shop/product_...roducts_id=124

Druken

Okay, thanks for that Revhed. So this is my current plan so far..
A Walbro 255lph pump and the surge tank from that website.
But do I need a filler pump like you?

trochoid

iTrader: (6)

Yes, you need an FI rated fuel filter. A stock carb filter will literally blow apart and will not filter fine enough for the injectors. On FI systems, the filter installs after the pump, carbs systems, filter installs pre-pump.

REVHEAD, sorry for confusing you with 13BEEF, that is the pic I was refering to. Very tidy install btw.

REVHED

Yes you need a filler pump.

REVHED

With FI, you need a low pressure filter before the pump and a high pressure filter after the pump. A bit of debris in the pump will kill it in no time.

I'm actually running three filters. A standard filter before the Carter, a 1/2" Volvo filter between the surge tank and Bosch EFI pump and an FC Rx-7 filter before the fuel rail.

Druken

I know this sounds very novice like, but Im getting confused... So I need...

Walbro 255lph Pump
Surge Tank
FI rated Fuel Filter (from a S5?)
Filler Pump

Are 3 fuel filters really neccessary? And what do you mean by a standard filter, the one that came stock with your car? And I'm guessing you would perfer the 1/2" Volvo filter too or what else would do?

trochoid

iTrader: (6)

Thanks for clearing that up REVHEAD.

Druken

I guess I can go ahead and find/purchase these goods. Just by looking at the list, I know I'll be digging a bigger hole within my wallet...

kenn_chan

You just figured that one out?

"its all fun and games until the wife finds out how much you spent, then somebodies gonna get hurt"

What I told my freind Harold when we were building his FD then his wife found out

kenn

REVHED

You need the high pressure filter before the fuel rail and at least one low pressure filter before the filler pump. I chose to add the volvo filter between the surge tank and EFI pump as it's cheap insurance against damage.

renns

My recommendation is to make it your first resort. The tools needed are very basic: drill, rivet gun, sheet metal snips. The tank can easily be modified and re-installed in a few hours. While the car's up in the air, swap out the old return line for a new 3/8" line, and use it as the feed. The old feed becomes the return. Add another hour or two for that work.

As for cost, my swap as documented in that thread was done for less than $50 including new fuel filter. Find a friend that's parting out an old FC, or visit the wreckers for an old tank already punctured to drain the fuel. Spend a bit of time with the snips cutting out the bits you need, and transfer them to your tank. The end result is a very clean, simple, cost effective installation.

82transam

iTrader: (18)

yea I'm with renns, I'm not sure what you plan to gain buy going with two pumps, a surge tank, and all those filters. Just a bunch of money and more places for leaks to occur. Not to mention the fact that its certainly gonna be louder than a in tank pump will be....

steve84GS TII

Surge tank setups give you the ability to keep everthing external and accesible.
Its easier to do than an intank,as far as fabrication is concerned.....but I agree,they are more complex and there are more exposed components that can leak.
The intank method is silent and simple.If its too technical for you to figure out,then leave it to a shop to cut/weld.If its too expensive for you to tackle.....then why are you dong an engine swap in the first place!?

Druken

Renns, I can get the 91 fuel pump assembly probably from a friend, if not finding someone on the forums selling one, but the mounting flange and slosh cup came from a 2nd gen fuel tank? Do people usually sell these, I have no access to a junk yard as of right now.