"hot wired" fuel pump?

ive heard of people "hot wireing" their fuel pumps with 12 volts from the battery on grand nationals when they turn up the boost to get a little more out of the stocker because the stock wiring harness leaves a little left on the table, will doing this and putting like a switch on the dash for it help keep my engine safer with say a 100-150 shot?

it wont hurt it
its been noted before (especially with the Buicks) that under load, the pump voltage can drop some because of other electronics running
hot wiring insures that the pump is getting maximum voltage (sometimes a tad bit more then stock) which will insure that your fuel pressure stays consistent

i think also that it has been mentioned that more voltage the pump sees, the less it has too "work" too keep pressure up...

basically, its one of those mods that wont hurt one bit too do, especially with a power adder where fueling is critical

ive heard of people "hot wireing" their fuel pumps with 12 volts from the battery on grand nationals when they turn up the boost to get a little more out of the stocker because the stock wiring harness leaves a little left on the table, will doing this and putting like a switch on the dash for it help keep my engine safer with say a 100-150 shot?


Basically all the "hot-wire" does is send a constant 13V to the fuel pump. Its a simple electrial harness with a relay, fuse holder, and some wiring. Run one wire back to the fuel sending unit and hook it up. We have companies that make "plug-and-play" harnesses for the Turbo Buicks. It was worth the $60 I paid for mine. But with a N20 system, I would seriously consider an upgraded fuel pump, like a Walbro 340. Holley, Edelbrock fuel pumps are all Walbros. They pump 255lph at like 50psi I think. I paid $100 for the pump kit from Anderson Performance Automotive. Summit Racing should carry the fuel pump, or your favorite F-Body vendor. :cool:


HTH.

If you're looking for a "plug and play" fuel pump solution take a look at the Racetronix kits:

http://www.harrisspeedworks.com/shop/home.php?cat=330

Let me know if you have any questions.
Matt

well i have a brand new gm fuel pump and sending unit all installed so i think for now im going to leave the stocker unless i opt for a bigger shot, i just want to make sure i get the best possible performance from it

You could try a hotwire kit. We have them, just not up on our website. Shoot me a PM if you have any questions.

Thanks,
Matt

well i have a brand new gm fuel pump and sending unit all installed so i think for now im going to leave the stocker unless i opt for a bigger shot, i just want to make sure i get the best possible performance from it

how much is it? i might think about it when i put the money together for the nx kit and all the accessories

Sent ya a PM.

Matt

how much is it? i might think about it when i put the money together for the nx kit and all the accessories

I ran quite a few bottles through my car (150 shot) internally stock without ever touching the fuel system. IMO it's not really necessary. I have a fuel pressure gauge staring me in the face when I drive, and never had any fuel starvation issues.

Once I swapped in the heads/cam, I tossed in a 255LPH pump for good measure. Other than the 30# SVO's I needed and the pump, it's stock, and I've yet to have any fuel problems. And I have as many electronic gadgets in the car as the next guy.

IMO, you'd be better off spending the time/money on a FPSS or fuel pressure gauge. Your stock pump setup should do just fine.

How much headroom did your stock pump provide as a safety margin?

Not all factory pumps are in the same condition. Many are down in performance due to their age. Some in-tank harnesses are burnt or corroded. Given the age of these cars it is always best to side with caution. Assuming your factory pump is up to the task could end up costing you much more than an in-tank pump. A HP pump is like having that extra insurance policy for your motor.

The HW harness will provide flow improvement with a factory pump but the gains are much higher with a HP pump such as our FLT1-FPA.

PS. Keep your eyes open on the new issue of GM High Tech Magazine. There is a full article on the installation of a Racetronix pump and harness in an LT1 car as well as injector replacement.