General Maintenance & Repairs Leaks | Squeaks | Clunks | Rattles | Grinds
Sponsored by:
Sponsored by: CARiD

Hot wire kit questions

Thread Tools
 
Search this Thread
 
Old Jul 1, 2025 | 12:50 PM
  #1  
wannafbody's Avatar
Thread Starter
TECH Senior Member
20 Year Member
Community Builder
Liked
Loved
iTrader: (3)
 
Joined: Apr 2006
Posts: 5,606
Likes: 1,151
From: Pittsburgh
Default Hot wire kit questions

Do I need to remove the original fuel pump relay from the fuse block when using a hot wire kit? Any issue with connecting the hot wire to the external positive post on the drivers side fender?
Reply
Old Jul 1, 2025 | 04:22 PM
  #2  
93Z2871805's Avatar
TECH Fanatic
Veteran: Air Force
15 Year Member
iTrader: (5)
 
Joined: Jun 2008
Posts: 1,736
Likes: 50
Default

In most applications, the factory relay is kept and simply acts as the trigger wire for the new larger relay provided in the kit. If the junction is direct from the back of the alternator, it should also see charging voltage, however the best source is to run the new pump wire directly off the back of the alternator to get the highest available voltage directly to the pump. The whole purpose of a hotwire kit is to give more than the typical system voltage of ~12.5v, with the alternator putting out ~14.5v. Any power source after the battery will only see around 12.5v.
Reply
Old Jul 7, 2025 | 04:06 PM
  #3  
TA_Freak's Avatar
TECH Fanatic
10 Year Member
Photogenic
 
Joined: Nov 2011
Posts: 1,367
Likes: 144
From: Woodstock, GA
Default

Also the thicker gauge cable will be able to handle the additional current demand without smoking anything.
Reply
Old Jul 8, 2025 | 11:09 AM
  #4  
WhiteBird00's Avatar
Ungrounded Moderator
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (4)
 
Joined: Nov 2003
Posts: 11,329
Likes: 346
From: Jacksonville, FL (originally from Toronto Canada)
Default

Originally Posted by 93Z2871805
... Any power source after the battery will only see around 12.5v.
Sorry, no. With the engine running, the entire electrical system sees alternator output voltage... just look at your voltmeter for confirmation. If in doubt, take a voltage reading at one of the light sockets or any other location where a device has direct power (i.e. where there isn't something else in the circuit providing resistance).
Reply
Old Jul 8, 2025 | 04:35 PM
  #5  
93Z2871805's Avatar
TECH Fanatic
Veteran: Air Force
15 Year Member
iTrader: (5)
 
Joined: Jun 2008
Posts: 1,736
Likes: 50
Default

Originally Posted by WhiteBird00
Sorry, no. With the engine running, the entire electrical system sees alternator output voltage... just look at your voltmeter for confirmation. If in doubt, take a voltage reading at one of the light sockets or any other location where a device has direct power (i.e. where there isn't something else in the circuit providing resistance).
You are correct, I misspoke in the point I was trying to make.

The absolute highest voltage with the least amount of drop in the system will come from the lug off of the alternator.
Reply
Old Jul 9, 2025 | 07:44 AM
  #6  
WhiteBird00's Avatar
Ungrounded Moderator
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (4)
 
Joined: Nov 2003
Posts: 11,329
Likes: 346
From: Jacksonville, FL (originally from Toronto Canada)
Default

Originally Posted by 93Z2871805
You are correct, I misspoke in the point I was trying to make.

The absolute highest voltage with the least amount of drop in the system will come from the lug off of the alternator.
Yes, that is true, although if you've done the big three, the voltage drop at the other end of the larger cables would be so small as to be unimportant.
Reply




All times are GMT -5. The time now is 10:13 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE