3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

Which relay to buy for Fuel Pump Rewire?!?!?!

Thread Tools
 
Search this Thread
 
Old Oct 10, 2011 | 09:21 AM
  #1  
curacaosfinest's Avatar
Thread Starter
1.3 Liter V8 Eater
Tenured Member 05 Years
iTrader: (12)
 
Joined: Sep 2008
Posts: 1,881
Likes: 2
From: Miami, FL
Which relay to buy for Fuel Pump Rewire?!?!?!

as the title states

theres like 5 different Bosch 30-40amp relays

i'm so confused, i'm not sure if they're all the same thing, just advertised differently or if some aren't waterproof or something

could someone post a link to the correct one, it would be nice if it was a link to a place that i could just click the "buy" button lol

thanks guys!
Reply
Old Oct 10, 2011 | 10:11 AM
  #2  
tom94RX-7's Avatar
Rotary Enthusiast
Tenured Member: 20 Years
iTrader: (5)
 
Joined: Apr 2005
Posts: 1,489
Likes: 4
From: Pittsburgh, PA
Any 4 terminal 30 amp relay from the local auto parts store should work, that's what I'm using. Like the one they sell in the isle with fog lights.
Reply
Old Oct 10, 2011 | 10:29 AM
  #3  
zeroG's Avatar
Rotary Enthusiast
Tenured Member 10 Years
iTrader: (28)
 
Joined: Aug 2008
Posts: 1,149
Likes: 0
From: Miami, FL
You don't really need one though, unless you're planning on having a manual switch to turn on the fuel pump.

You can just run it straight through the fusebox in the engine bay, easier and cleaner imo
Reply
Old Oct 10, 2011 | 10:34 AM
  #4  
tom94RX-7's Avatar
Rotary Enthusiast
Tenured Member: 20 Years
iTrader: (5)
 
Joined: Apr 2005
Posts: 1,489
Likes: 4
From: Pittsburgh, PA
You may need or want a relay to get more voltage to your pump and more output from it, it works better, I've done both.
Reply
Old Oct 10, 2011 | 11:51 AM
  #5  
curacaosfinest's Avatar
Thread Starter
1.3 Liter V8 Eater
Tenured Member 05 Years
iTrader: (12)
 
Joined: Sep 2008
Posts: 1,881
Likes: 2
From: Miami, FL
ok cool thanks guys
Reply
Old Oct 10, 2011 | 01:16 PM
  #6  
G's 3rd Gen's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member: 20 Years
iTrader: (11)
 
Joined: Sep 2003
Posts: 3,067
Likes: 7
From: Home of the Rolex 24
Like Tom stated if you plan on running some higher horsepower this one's a no brainer. http://rx7.com/store/rx7/fuelpumprelay.html The standard ones tend to heat up and wear out over time. This one might seem like overkill but for the price its peace of mind. Wont leave you stranded. G
Reply
Old Oct 10, 2011 | 02:58 PM
  #7  
NoPis10's Avatar
Committee Member #2
Tenured Member 15 Years
iTrader: (29)
 
Joined: Jan 2005
Posts: 4,280
Likes: 5
From: Committe Chambers
Damn... G

That looks like a starter soleniod for a Ford from 1990....

Tom is right, any relay works, the best out there are Bosch but trying to get one is almost impossible. I went to many stereo shops and auto parts and no one carries them anymore so I bought what they sell. I also bought a spare and will keep it in the car just in case..

L8R
Reply
Old Oct 10, 2011 | 03:06 PM
  #8  
tom94RX-7's Avatar
Rotary Enthusiast
Tenured Member: 20 Years
iTrader: (5)
 
Joined: Apr 2005
Posts: 1,489
Likes: 4
From: Pittsburgh, PA
I'll have to put a spare in my car too. But if the relay fails then you just have to connect two of the wires together off the relay to get the power to the pump to get home.
Reply
Old Oct 11, 2011 | 08:48 PM
  #9  
IWINULUZ's Avatar
Senior Member
Tenured Member: 20 Years
Liked
Loved
iTrader: (10)
 
Joined: Jul 2005
Posts: 407
Likes: 2
From: Charlotte,NC
Single pull double throw relay. I still have like ten brand new ones with new harness if you want PM me I sell and ship cheap.
Reply
Old Oct 11, 2011 | 08:52 PM
  #10  
theorie's Avatar
AponOUT!?
Tenured Member 15 Years
iTrader: (31)
 
Joined: Nov 2002
Posts: 3,521
Likes: 13
From: Sarasota, FL
Don't forget:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/word-about-re-wiring-your-fuel-pump-%5Bpics%5D-921896/

and

https://www.rx7club.com/classifieds-violations-265/theories-why-im-always-poor-1993-ssm-build-951172/page8/
(scroll down to post 189 and after)

Hope that helps...
Reply
Old Oct 12, 2011 | 04:10 AM
  #11  
ttmott's Avatar
Senior Member
Tenured Member 10 Years
iTrader: (1)
 
Joined: Aug 2006
Posts: 398
Likes: 8
From: Space Coast Florida
Always use relays for switching high current components. A fuel pump definately requires a relay; I would never use an ECM to directly operate a fuel pump. You can use four pole or five pole relays. I typically use the 50 amp rated relays; they are good for just about anything except for main power switching and for four or five bucks - cheap.

Waytek has an appropriage selection:
http://order.waytekwire.com/products...d%20Solenoids/

They also have the sockets for the relays:
http://order.waytekwire.com/CGI-BIN/...472002+M50+ENG

Your local NAPA also has all of this stuff......
Reply
Old Oct 13, 2011 | 10:11 PM
  #12  
Howard Coleman's Avatar
Racing Rotary Since 1983
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (7)
 
Joined: Oct 2001
Posts: 6,279
Likes: 728
From: Florence, Alabama
the wrong relay can destroy any and all solid state modules in the elec system.

the relay must have either a diode or resistor in it to suppress voltage spikes that can be 100-200 volts when the magnetic field collapses.

note the sticker on the relay in the above rx7.com link...

i currently have two Power FCs being rebuilt due an improper relay,

howard
Reply
Old Oct 13, 2011 | 10:59 PM
  #13  
tom94RX-7's Avatar
Rotary Enthusiast
Tenured Member: 20 Years
iTrader: (5)
 
Joined: Apr 2005
Posts: 1,489
Likes: 4
From: Pittsburgh, PA
The rx7.com site also says about their relay "This is a competition part that is only needed on dual pump or external pump applications."
Reply
Old Oct 15, 2011 | 03:42 AM
  #14  
G's 3rd Gen's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member: 20 Years
iTrader: (11)
 
Joined: Sep 2003
Posts: 3,067
Likes: 7
From: Home of the Rolex 24
I have been using this for four years and never had a pump problem. Pump rewired with 10 gauge wiring. I had two small relays fail on me in three years previous and the car only sees three to four thousand miles a year. G
Reply
Old Oct 15, 2011 | 07:37 AM
  #15  
BLACK MAMBA's Avatar
FD Project
Tenured Member: 15 Years
iTrader: (58)
 
Joined: Apr 2009
Posts: 2,376
Likes: 4
From: Palm Beach, FL
this is the one im using, 40 amp sealed housing. you have to make the wiring.
http://www.bmotorsports.com/shop/pro...roducts_id/503


best thing is you could do any gauge wire and not be stock with premade pig tails that either the wire gauge is to small or you have to solder wires to extend the pigtails to your pump,fans or coils.

you could also find here the injector connector kit
ignition coil connector/same as toyota

Last edited by BLACK MAMBA; Oct 15, 2011 at 07:39 AM.
Reply
Old Oct 31, 2011 | 12:00 AM
  #16  
tom94RX-7's Avatar
Rotary Enthusiast
Tenured Member: 20 Years
iTrader: (5)
 
Joined: Apr 2005
Posts: 1,489
Likes: 4
From: Pittsburgh, PA
I just ordered a 70 amp relay from McMaster-Carr that "can handle a high-inrush current of up to 120 amps", part number 9672K36 $13.64 .

http://www.mcmaster.com/?orderview=n...17/895/=eq3aws

I'm also going to order some Insulated electrical bulkhead connectors to get my fuel pump rewire down to the pump.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Queppa
New Member RX-7 Technical
11
Nov 18, 2024 03:47 AM
trickster
2nd Generation Specific (1986-1992)
25
Jul 1, 2023 04:40 PM
Rotospectre
New Member RX-7 Technical
3
Mar 28, 2018 03:33 PM




All times are GMT -5. The time now is 08:32 AM.