Is there any other source besides Racetronix?

Those who are using them, anybody buy and use the additional wiring harness. I've seen the site, but until I measure my own voltage levels I'm not convinced it makes any difference.

Don't mind spending, hate wasting.

 

I bought mine off of eBay for $32.00. It was listed to fit a Mustang, but once I bought the phord sock, it fit right in. There was minor wire splicing to do. Works like a charm.

RACE ON!!!

 

this is where i got mine at
http://www.cottonsperformance.com/

 

Would you install a stereo amplifier in your car that draws high current and splice it into your factory radio's thin wiring or would you run a dedicated heavier gauge wire to the amplifier?

A Walbro HP pump can draw twice as much current as a factory pump. Look at the Walbro spec sheets, look at the vehicle tests and the answer is quite clear. You can perform a search on this board and find other Corvette owners who have benefited from the Racetronix system. C5 owners who have installed the Racetronix harness prior to installing our pump have had a substantial increase in pressure and volume. The C5 has better wiring than the C4 to start with. Going from 12V to 13.5V on a Walbro pump nets an approximate gain of 18% gain in flow. Perhaps a Walbro 255L/Hr pump is already overkill for your HP level so you don’t need to meet the factory specification at 13.5V. Worst case is the harness takes the load off the factory system thereby extending its life and possibly extending the pump’s life. This is probably one of the cheapest upgrades one could add to their car but yet has the potential to save much money in the long run. Don’t forget the fuel system is your motor’s life line under WOT.

PS. Turbo Buick owners have been using these types of harnesses for years knowing full well the benefits to be had. This is an old idea that Racetronix has made available to other vehicle platforms.

Racetronix http://www.racetronix.com

 

Thanks for the reply, I do have some more questions. Thats my point. Don't get me wrong, I'm not trying to knock your product, I know a lot of people use it with great success and thats why I'm interested in it. I'm trying to determine if I need the harness for my application and to understand how it can benefit me.

I understand your gains come from the use of 10 gauge wiring having less voltage drop than the stock 16 gauge the factory used. But why do you use a 12 volt reference on your flow table when you show the factory wiring providing 13.19 volts? Since the factory wiring connects directly to the positive side of the battery, through the relay, and should provide alternator output level voltages to the fuel pump, shouldn't you be using 13.19 to determine flow?

Now I'm running a modified TPI setup with 23lb injectors set to 47psi. Even using the 12 volt flow numbers @50psi this pump should provide me 204 liters/hr. Do you feel this is inadequate for my engine?

I admit I have no idea what the stock pump flows or what its current requirements are. The factory spec you mention above, is this a GM spec or a Walbro spec? Do you have any specifications from Walbro other than whats listed on you site?

Since you replace the existing harness, this now becomes a switched constant on system, i.e., I lose the 2 second prime and oil pressure switch functionality? This is no big deal, are there any other differences from using this?

Thanks again for the info...

 

The voltage shown in our ad is at idle, low pressure with a fully charged battery, cold alternator and no power accessories running like fans, A/C, defog etc.
Under WOT conditions with higher pressures, a heat soaked engine compartment and accessories running this is a totally different picture.

The factory route is as follows.
Undersized alternator wire feeding battery
Battery cable feeding starter
Fusible link resistive wire feeding fuse block / distribution point
Steering column ignition switch feeding fuse panel section
Fuse panel feeding fuel pump relay
Relay feeding pump through a few links and undersized wire

The Racetronix harness plugs into the factory harness at the back of the car with factory type connectors. The factory system (ECM + relay + oil pressure switch) triggers the relay in the Racetronix harness (which only draws about 0.1A) which in turn provides alternator direct power. The voltage at the alternator is always higher than at the battery providing further gains. This voltage differential widens as the alternator's electrical load increases.

The specs given on the Walbro pumps are legitimate docs from Walbro engineering which can be found all over the net. We have also backed up these specs with our own in-house tests as well as in hundreds of customer's cars. A Walbro pump's performance is a well proven commodity so there are no doubts that they do deliver. You can expect 550-600RWHP support under NA applications with a Racetronix HP kit.

Jack :cool:
Racetronix http://www.racetronix.com


[Modified by Racetronix, 5:24 PM 12/28/2002]

 

You know 1Moor, I would would have to agree...most of the aftermarket crap out there requires, fitting, re-engineering, Maalox. I have got to say, (as I have posted before) this Racetronix setup is TRUE plug N' play. And, IT WORKS! Imagine that! I took my lead from a friend that I introduced the EASE software to while chassis tuning his monster MORE Performance 396 motor. Kept missing at WOT after he went to a HUGE cam. Noticed that his pulsewidth was huge, and some other parameters pointed toward fuel starvation. He plugged in the Racetronix setup and it totally cured the problem. Because I went to a hotrod stroker motor with a merely "big" cam, I didn't event think twice. I have never met, or even spoken to the guys at Racetronix. Bought it purely on the recommendation of a trusted member and friend.

 

Wow something we can agree on :cool:
I've got the same setup from Jack @ Racetronix, very clean install, knowledgeable fella' to talk with also.

I measured the voltage with it running after the kit at 14.4 V near the rear most plug-in, mounted my relay & wiring behind the license plate area.

 

I installed the pump but have yet to install the wiring harness. I'll get to it in the spring...........but I must say the pump alone works like a charm! :cheers:

 

If you're adding forced induction or nitrous this is an important part of the total package. On a normally aspirated motor it will provide the fuel necessary in the high RPM range for maximun performance tuning. If you have forced induction or nitrous fuel supply becomes critical to the life of the motor not just it's performance.

For any power adder the Racetronix setup is cheap insurance against costly engine damage from going lean under boost. I have one that is going to be installed for peace of mind with a NX wet kit. I'm at the upper limit of the stock fuel pumps capability now anyway. The included harness is a well thought out and well engineered design. Just my two cents.

 

I bought my Walbros among other thing from Ron
http://www.autoperformanceengineering.com/

IMO Unless you pushing well over 500hp or running at higher fuel pressures in Supercharger via a FMU, the additonal harness isn't needed.

 

"Well over 500HP." How much over? Is that RWHP or FWHP?
How much safety margin is in there?
At what vehicle voltage is that?
Is that on a cold winter's day with a new fuel filter or on hot summer's day with a dirty fuel filter?
Is that with a fully charged battery and no accessories on or with a discharged battery and the defogger, headlamps and stereo cranked?

Those are very vague guidelines for deciding whether or not the upgrade harness is required. Any gain in pump performance is a good idea and it could also extend the pump's life. Considering what other HP parts cost for a Corvette the harness is a drop in the bucket for some great insurance.

If you only need a 190L/Hr pump then buy one.
Don't spend the extra money on a 255L/Hr pump expecting to get its rated output and then use the vehicle's electrical deficiencies to degrade it performance and possibly shorten its life.

Jack :cool:
Racetronix

 

I was refering to 500 flywheel hp. Three of the guy posting have under 400hp and probably closer to 300hp. I don't diasgree that a fuel pump is a good insurance, but I think the wiring is overkill on TPI car or crossfire car, when the pump itself it already overkill. C4 aren't like GN where they are running higher pressures due to boost and have a really crappy fp wiring. A 255 walbro will flow 800 at stock c4 fuel pressure levels, so what if you losing fp performance, even at 12 volts its over 700hp. You going to need an extreme combo to come close to even needing the full pottential of a walbro unless it is a SC with a FMU. I know quite few people using the stock pump to over 400hp, I don't even know what the stock pump flows, 80-100 lph?

I personally have never seen any data to show a pump lasting long at higher voltage. IMO the higher voltage could create more heat and load which will shorten its life, but I that is only my intuition as an EE. (Please don't take that as a fact!)

 

In my experience your stated HP numbers are way over-exaggerated. Racetronix works closely with many HP tuners and engine builders. As well, I have been tuning cars on the dyno for over 12 years and I have yet to see a Walbro 307 or 340 come anywhere close to supporting 800HP on a fuel injected car running apx. 44PSI fuel pressure or less.

As far as a C4's wiring... it is not much better than a Buick's FYI! GM uses pretty much the same layout in all cars of that era. A C4 will typically drop 1.5 volts under WOT while a Buick might be around 2.0 volts. (Assuming both car's have a healthy charging system and battery). Most of the difference between the two car’s voltage-drop can be attributed to slightly shorter wire lengths and the omission of the TR / Buick’s aluminum wiring section to the trunk in the C4.

I will not get into a debate on electrical theory (I am an E.E.T. BTW) and how voltage will affect a motors life as it would get way too technically involved for this thread. Too little voltage will stall the armature under load causing increased current draw (and more I2R losses in the harness – we all know what happens to a DC motor's brushes when we stall the armature). Too much voltage can overheat the motor and cause the pump gears to cavitate thereby reducing flow. Walbro engineers have stated that their pumps can be run at 15-16 volts with little effect on their lifespan. 13.5-14.5 volts are where the pump’s motor runs most efficiently. We have thousands of customers running our harnesses with a lower than average pump failure rate. Perhaps the harnesses and body ground kits are making up for deficiencies in the well aged electrical systems? Many kits we are selling are going into vehicles that are approaching the 20+ year mark.

Jack :cool:
Racetronix http://www.racetronix.com


[Modified by Racetronix, 1:24 AM 12/29/2002]

 

can you guys tell me about this harness?? i think ill need it. My motor (almost ready to install) wil make over 450 rwhp and rev 7500 rpm. I have a walbro pump i put in the car 2 years back, but never heard of this harness. im pretty sure it was wired to the factory harness.

help !?! :confused:

 

Have you read the ad here?
http://www.racetronix.com/Racetronix-C44-FPK.html

Racetronix http://www.racetronix.com