Eagle02

iTrader: (20)

I've got a hotwire kit in the garage for my car, but I haven't really thought that I needed it.

My injector duty is @ 75% max. I will be running a wet kit on the car as well.

Does anyone have experience with the differences that a hotwire kit can make on a car?

letsrunem

iTrader: (15)

Higher voltage seen at the pump=more flow.

Eagle02

iTrader: (20)

Is it really that simple? I'm just wondering what kind of gap the hotwire kit is capable of clearing up.

Nasty N8

iTrader: (33)

Are you running a higher volume fuel pump? The stock wiring can not handle the extra amperage the pumps draw and will burn the wires powering the pump. That and mentioned more voltage more pump volume.

Nate

Eagle02

iTrader: (20)

I'm running a racetronix 255 pump. Lake in the hills? You're right around the corner from me...

Nasty N8

iTrader: (33)

Cool...but DEFIANTLY if you are running the pump add the harness or you may have more problems to deal with. Seen alot of burned stock harnesses from the added draw. Not to mention the voltage drop with the small wires in the stock harness. Get that pump good voltage from the alt.

Nate

Eagle02

iTrader: (20)

Alright, you convinced me. I'll pull out the box and look @ getting it installed tonight.

bigcraig987

Shouldn't the fuse blow before the current level gets to point where it is heating up enough to damage the harness since the point of having fuses it to protect the device and harness

Racetronix

iTrader: (2)

Not in all cases.

spaulsen

iTrader: (12)

what does one of these kits cost and where can i get one?

bigcraig987

Well unless someone tampers with the setup like replace the fuse with a higher rated one or put a jumper wire in there or something what would be a case.

Out of curiosity how much current draw is typically seen, peak during wot and normal operating, from the higher flowing pumps such as the walboro 255 lph anyhow.

Edit: In addition, from the pictures of the kits I have seen including the racetronix kit, I can see the fuse used is yellow which the color code says is a 20 amp rating, I then went outside just now and looked at the stock fuse and saw that it is also a 20 amp rated fuse, so I am just trying to understand that if GM felt that 20 should protect the circuit, why is there a need to up gauge the wire for reasons of current draw protection and have the same fuse protection. I don't deny that the voltage drop will be less but I don't see where there current protection argument is. If people have have experiences with stock harness failures without changing the fusing or other tampering feel free to chime in.

stonemonk

iTrader: (12)

sounds stupid but.... is there a how to on this? my kit did not come w/ instructions or anything... im guessing the just plugs into the the connector at the pump and mount the relay under the car? Power is supposed to come off the alt right??

jetlag

iTrader: (32)

Yeah, it is real easy...and just follow the brake lines underneath the car.

Racetronix

iTrader: (2)

You can order them via our web store www.racetronix.biz or through a dealer listed on our web page www.racetronix.com.

Racetronix

iTrader: (2)

The problem with the factory wiring is sometimes resistive in nature. If there is a point of higher resistance in the factory harness then the current demand would go down while the point of failure might heat up, arc, melt, fail... This is why many residential panels now have arc-fault breakers. Unfortunately automotive power distribution safety features are not quite as robust. Maybe if they were we would not see so many automotive electrical fires?

Nominal current draw on a Walbro 255LPH HP pump operating at 58PSI is apx. 10-12 amps. The 20 amp fuse is usually high enough to handle the inrush / start-up current but small enough to blow if any excessive current starts to flow. If you run a booster then a 25 amp fuse should be used.

Racetronix

iTrader: (2)

Yup, just mount the relay near the P/S rear shock as shown in this picture:
http://www.racetronix.com/product/RX.../Dcp_1169a.jpg
Clean off the rust, apply the grease supplied, mount the relay with the chassis ground terminal and replace / tighten the bolt.

bigcraig987

From that it seems to me that you are saying the stock harness should be fine to handle the current draw for the new pump under normal conditions unless it is defective or damaged leading to additional resistance. Saying that something has a chance to fail if it is damaged or defective can be applied to most things including heavier duty aftermarket pieces including your wire kit. I don't think that saying a damaged or defective stock harness could fail is a valid reason to say that the stock harness needs to be replaced, obviously if the harness did appear to have problems then it should be replaced, and everyone just visually inspect and pull out a multimeter to check the resistance if they are concerned. Now saying that a hot wire kit has the ability to run at higher current values that may be seen when running a booster is a different story. Perhaps that should have been the point made earlier rather than just stating that the stock harness cannot handle the current draw of a pump like a Walboro 255 lph, since by your statement it seems it can handle it if it is in good condition.

Racetronix

iTrader: (2)

No, pump performance will suffer by the percentages quoted in our web ad b/c of the voltage-drop caused by the resistance of the factory harness. We are talking about two different issues here. One being performance and one being reliability.... and the load can in some cases cause the factory harness to have issues as well.

bigcraig987

I thought I was pretty clear but I will break down my logic step by step.

First, I was'nt saying there couldn't be a performance gain with having less voltage drop.

I was just questioning when it was said that the stock harness would not be able to handle the current draw of a new pump since it is fuse protected.

See in earlier post "but DEFIANTLY if you are running the pump add the harness or you may have more problems to deal with. Seen alot of burned stock harnesses from the added draw."

I further questioned this when I saw the kits used the same fusing as the stock harness. Then you stated that the problem with the stock harness was:

"The problem with the factory wiring is sometimes resistive in nature. If there is a point of higher resistance in the factory harness then the current demand would go down while the point of failure might heat up, arc, melt, fail..."

I took this to meaning that the harness might fail if it is defective or damaged creating excessive resistance. I though that was not a good reason to say that the stock harness can't handle the added current draw because anything can fail when defective or damaged including heavier duty aftermarket pieces, so I said so, while recognizing the kits ability to handle more current that may be seen if a booster is used, if necessary I don't really know how much more a booster creates.

From all of theses responses it seemed that
1) there can be a gain with a kit along the lines of less voltage drop
2) the stock harness can handle the current of normal loads of a pump like a walboro 255 lph
3) there is an advantage of the kits to handle additional current loads beyond normal operation if need be like if a booster is used

If my logic doesn't make sense to anyone there let me know.

Racetronix

iTrader: (2)

1) There WILL be an improvement in pump performance with the harness which will support more HP.

2) The stock harness will support the load of a Walbro / Racetronix HP pump with reduced performance. Resistance in the factory harness is its own enemy which may cause accelerated failure. Most often terminals and relay contacts fail first.

3) The harness will provide added benefits when using a pump booster like a KB or MSD unit.

4) The harness also removes load from the vehcile's electrical distribution center which may benefit other circuits as well. Some vehicles share the fuel pump circuit with other devices such as the ignition system or fuel injectors.