RAIN H8R

It is important to note that the sos wire kit is a great bang for buck. It increases the wiring diameter from the battery to the trunk area, it also includes pins to literally replace the stock wiring.

simply running a larger wire to the sender power wire is not the answer. You need to repin the wiring on the connector of the sending unit (power and ground). In addition, the wiring inside the tank needs to upgraded too along with new pins. All of the wiring is gas resistant to prevent fuel wicking through the wiring.

in short, buy the sos fuel pump wiring it!

It has been long documented that voltage tapers off on ap1 cars near redline. The rewire solves this to allow the pump to run efficiently.

Jaspah

I live in the Netherlands, so shipping would take a while. Plus I've moved my battery to the trunk, so it's right next to the fuel pump. This is why I tried something myself.

I never knew about a fuelpump rewire, untill you told me. So thanks for that! I looked into it, and fixed it myself. Pretty easy mod.
The whole idea behind this fuel pump rewire is to cut the loss in voltage you have in a few meters of wire (DC loses voltage over a certain ammount of lenght of wire)
By directly connecting the fuel pump to the battery, you get +/- 14.4VDC when the altenator is running. This way the total power output of the pump rises.
No need to upgrade the wires all the way to the pump. By doing this rewire, you will gain a few tenths of Volts, meaning the pump will draw just a very small percentage of extra amps
(U=I*R .... Resistance stays the same, U gets boosted a little, so does I )

There is no way a few tenths of extra amps will melt the connector, make the small wires too hot or anything like this.

I'm still running a 10A fuse between the battery and the relay.



So long story short:

I cut the plus to the fuel pump to power the relay. This simple 4 pin relay is between the battery and pump, get activated by turning the key as usual.
The pump sounds healthier and because the injector duty cycle was still @ 97% +/- I gained some A/F at high rpm's. Now it's running a bit less lean, which is exactly what I wanted.

So simple fix, and recommanded to gain some extra pump power

Thanks all!

s2000Junky

Ive been procrastinating finishing the sos rewire on my ap1 because of all the re pinning work. I ran the thicker dead wire from the batt to the trunk and stopped there. When I tested what the voltage gain would be via meter from the oem connection vs my new wire, it was .2v. If there is a way to bypass re pinning the fuel pump connector and mitigate some risk with melt down/failures ive come across at the plug wile still getting the full benefits, I'm all for it. However with wiring not being one of my strong points, I'm not totally clear from the poster 'Jaspah' above how to execute that properly.

Jaspah

The big plus in this trick is not to use thicker wires, but shorter wires (in totall)

So connecting the fuelpump + directly to the battery and the - to a closeby point on the chassis, saves a few metres of cable, in which you can gain some volts.

volcomboy390

What if your car is a 07..... I have a novi 1200 on it at 12psi with an aero 340 pump and id1000.

My tuner says my fuel system is maxed out on 91 octane and made just shy of 360whp. He said he had to start pulling timing as well.... does this sound right??? I was hoping to get to 400whp with out dropping $1000 on a fuel return system. (Can't recall duty cycle)

im in California, with flashpro, so my options are either straight 91 or straight E85.
Do I have any options to get over this 360 mark....

MorngWoodStewie

I'm a MY07 with ID1k, 255lph, 92 Oct. And return less. 422//295 TC.
Pertaining to just your question; I do not see how ur system is maxed.

Jaspah

Something is not right I think. Maybe a block somewhere in the fuel feed?

volcomboy390

I don't know enough about tuning to figure it out myself but I have spent a lot of money to try and get to 400whp and 2 years later I'm still not there... also I'm averaging about 14-15 mpg city driving.... does that seem right. I think I might have to have Evasive look over the tune. Does anyone do supercharged flashpro e-tunes?

i agree with the previous posts.... something doesn't seem right! This is with 91 octane.

s2000Junky

I see a fair amount of situations from members here dealing with similar issues, and it seems to be contributed to tuners chasing phantom knock and end up pulling considerably more timing then needed, and as a result end up yield significantly less power then otherwise typical with a proper tune. There are other situations where someone may have a bad/plugged stock cat which can create this real knock situation for the tuner. Other unrelated issues that yield less then expected power can be a slipping SC belt or clutch, or a bad aftercooler pump, kinked lines etc preventing proper coolant flow/IAT cooling.

A novi 1200 at 12psi is worth 400whp all day. If your yielding much off that mark, something is amiss.

MorngWoodStewie

If ur looking for someone that does e tunes specifically for the s2k I would hit up derftuned IG<
He should be able to take a look at what u got at the least.