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Discussion Starter · #1 ·
I need some help in tweaking the J&S. If anyone is knowledgable in this, please help! :(

Thanks!
 

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Discussion Starter · #3 ·
Thanks Graham,

OK, I'm running a Ludespeed Stg2. kit, I have the Map limiter (clamp) on the J&S set to 4.77v

Now, I don't know where should I leave the 'sensitivity' knob? Halfway? all the way sensitive?

(I currently have a LEAN problem, when I get on the gas, and go into boost, my autometer A/F gauge (I know, not the most precise one), goes towards lean, and even dissapears! I believe my FPR is bad, I have a Vortech RRFPR 12:1. My friend has the exact same kit, on the exact same car, and his is running without det. I get det. once I go lean, and can feel the J&S kick in. :( )

Oh yea, and my fuel pump (Walbro) is LOUD AS HELL! :)

Any thoughts?
 

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OK, do you have the J&S retard monitor on your car? You see, this is a great tuning device, as it displays and lets you know exactly when you are retarding. I have the display on my car, and I have my J&S sensitivity knob set to where it retards very little, due to engine noise, not det.

One other thing, do you have a Fuel Pressure gauge? How long have you had the setup on your car? And, how much boost?

Here is the thing about the RRFPR: Mine wouldn't raise boost on my car for a few days after I had my turbo. I found that my vaccum line going to the Vortech was too long and the unit wasn't seeing any vaccum, therefore not raising my fuel pressure. I shortened my vaccum line, and it started raising pressure. I don't know how long this has been like this on your car, but try shortening the vaccum line to the Vortech, and you might be pleasantly suprised. A fuel pressure gauge would tell you immediately if you are raising pressure or not. If your A/F gauge is saying lean, then I am guessing your RRFPR isn't working, especially with the 12:1, thats A LOT.

I don't get any det on my car with the J&S either, you have a problem.


Graham
 

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12:1?!?!?!? That's way too high. if you're idling a say 40 psi (probably closer to 50 with the Walboro) then your upping the pressure another 12 psi / 1 psi boost. At 4 psi boost you're running 88 psi or more, you're poor injectors. Another thing to consider, are you running stock plugs or colder plugs? What is the gap? Too hot a plug or to big a gap will cause detonation also.
 

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Discussion Starter · #6 ·
Graham: No, unfortunately I don't have the monitor. Just bought the unit itself. I haven't put in a fuel pressure gauge yet either.
Kit (6.6lbs wastegate spring) has been on my car for about 2 months now, close to 3k miles.
Here is the weird part, we installed the exact same kit, on my friends car (exact same car), and he is running fine. No det whatsoever. :(

Boy: 12:1 is what I got from Tom at Ludespeed. :confused:
Also, the kit came with colder plugs.

I think I've narrowed it down to the RRFPR being bad. I definitely know it is a fuel problem. I've contacted Tom to see what we can do.

Thanks guys.
-Vic
 

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Vic, good luck man. I'm hopin to get mine up and running in a couple of weeks and I've already run into problems with engine management and slow delivery of parts :rolleyes: so much for an "easy" custom kit.
 

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Yes I think you do have fuel problems...

The monitor on the J&S will help a lot with tuning it, otherwise you are pretty much in the dark. Please do try and shorten the vaccum line going to your RRFPR, I think that could be the problem. It was with mine at least.

Bill, there is NO SUCH THING as a simple or easy install, there will always be problems.


Graham
 

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Discussion Starter · #9 · (Edited)
One other question regarding the J&S.

If I disconnet the MAP Limiter and use my SplitSec Voltage Clamp instead, will the J&S still work? Will it still be able to sense knock and retard timing?

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I would think it would still work, but I don't know. I have the V1 J&S, so its a little different. Why would you want to do that anyway?


Graham
 

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Discussion Starter · #11 ·
Well, the reason I ask is that I got stuck at 3am on new years. :curse:
Had to leave the car at a parking lot.
Well, the symptom was that it would turn over and die. If you'd try to give it gas, it'd die also. After looking at everything, even swapping out my fuel pump for my stock one, I decided to look at the J&S. I checked the voltage on the MAP limiter, and it was reading less than 2v!! I tried turning the pot. knob, but didn't get more than 2v. When I disconnected the bridge, and plugged back the MAP sensor to stock (i.e. without a clamp) car started up perfect and idled fine! Now I have my SS voltage clamp on there, and it looks to be OK. But I don't think the J&S is working though. Wiring looks fine. Strange thing is that car just died all of a sudden at a stop light, I wasn't even pushing it or nothing that night. :confused:
 

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Geese man I don't know. I do know that most people with the J&S V.2 don't use a SS Clamp. They simply use the one that comes on the J&S. Clamps can be a very screwy thing, I am learning this right now on my Link with my car.


Graham
 

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Discussion Starter · #14 ·
I'm sending the unit back to John @ J&S. He says not to worry, he will take a look at the unit, and if he cannot fix it, build me a new one. Now THAT is what I call warranty. :sunny:
 
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