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Discussion Starter #1
Well, I've been tuning my AFC with my UEGO for a couple days now trying to get my perfect fuel curve. Go pretty good thus far, just have a few more tweaks to make. But in the upper RPM's I'm still pulling timing like a MOFO. The car is still sluggish up top, doesn't make sense to me because I thought the AFC acted as the map clamp to help fix the timing problem. I'm getting a 11.4 a/f right now on my way to an 11.8....will it get better as I get closer to my 11.8? My fuel mods are S1 with 80 psi PT FPR. I'm boosting 20lbs.

thoughts?
 

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First off, the butt dyno is not the best at judging power so do remember that.

There is alot more to timing than just "clamping" at a certain voltage. Most likely you are getting some knock at those high boost levels on the stock turbo and the PCM is pulling the timing back. Doesn't matter how your fuel curve is, if you are knocking you will loose power. An easy way to check this is to run the tank low till the gas light is on and then go throw in some 100 octane unleaded race gas. Throw in maybe 4 gallons or so. Then without any changes to the fuel map run the car again and see if you pick up the power in the top end. If you do then your problem is related to knock.
 

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Discussion Starter #3
Interesting....I haven't read on here about anyone having problems with knock on 93-94 octane. I thought that was a problem with the Cali guys and 91 octane. When I get my tech guages I'll see what's going on
 

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What voltage is the afc clamping at?

A SAFC has a function that will allow you to see the map voltage going to the pcm, I just can't remember how to access it.

You didn't say what afc you are using.

You may not be clamping enough, in which case you would need to lower your boost and fix your a/f ratios by pulling more fuel.

OR, you could be knocking, which is caused by much more than just fuel. High IAT's will also help contribute to detonation. Do you have a fmic?

Wait tell you get your gauges in before you start doing anything wild, but the above are my two guesses as to what could be happening.

TJ
 

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Discussion Starter #5
I'm using the SAFC II and yeah I have the CCA Large FMIC. I pulled 8% across the board last night and the car reacted ALOT better, didn't get that hesitation feel I got before at the High RPM's. I'm hitting a solid 11.6 a/f right now, gonna try pulling 10% out across the board and see what A/F that puts me at.....hoping for 11.8-11.9

To check the voltage, don't I just have to do the sensor check while I'm at WOT? And that displays my voltage from the map?
 

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forget checkign the Voltage man just lean out the car 12:1 and ull be good, the more fuel u take the better it will feel because more timing
 

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Discussion Starter #7
I pulled 10% across the board today and got a solid 11.7 A/F....When I tried to pull 11% my A/F went up to 12.2-12.3. So, I guess I'm going to leave it at 10% and be happy even though I wanted around an 11.9. I need to do some fine tuning, but that's gonna wait till I get to the dyno and get an A/F readout and make my changes then
 

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I am having the same freakin issue as you!! I have the 75psi FPR mod... But once it hits 4800RPMS it feels like I am maxing out the injectors and it falls on its face! (No fuel cut). I emailed PTperformance about and he told me to remove my coilpack (I have MSD, Doh!) Why would this help!!?!?!?

I am hitting 21-20psi then it drops a down to about 17psi and right at that gayspot 4800RPMS it hits 15psi or lower? I dont think I have any boost leaks. I have zip tied everything and tightened all hoses ect. The only leak I had was the factory TB one... and a lil ripped coupler which is fixed! :tongue: I am clamped at 4.7v and again at the certain spot (4800RPMS) maybe a lil bit after it drops to 3.9vlts.

My mods: Stage 1 PCM & Injectors, AGP WGA, AGP Direct FIt FMIC, SAFC II, Full 3in. Exhaust (MaxxFab REE), SRI (K&N FPIK), MSD 8.5MM wires, NGK 4306's ACT Clutch and LC1/XD1 wideband.

Any thoughts guys? I am all outta them... Here is my maps for my AFC:

NE-PTS
800RPM: -4%
1200RPM: -2%
1800RPM: -2%
2400RPM: -5%
3000RPM: -8%
3600RPM: -8%
4200RPM: -8%
4800RPM: -4%
5400RPM: -1%
6000RPM: -0%

Throttle PT
Lo: 10%
Hi: 40%

Dec. Air
THR: ****%
Ne1: 10%
Ne2: 10%

Thanks, Jeff
 

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JsSRT4 said:
I am having the same freakin issue as you!! I have the 75psi FPR mod... But once it hits 4800RPMS it feels like I am maxing out the injectors and it falls on its face! (No fuel cut). I emailed PTperformance about and he told me to remove my coilpack (I have MSD, Doh!) Why would this help!!?!?!?

I am hitting 21-20psi then it drops a down to about 17psi and right at that gayspot 4800RPMS it hits 15psi or lower? I dont think I have any boost leaks. I have zip tied everything and tightened all hoses ect. The only leak I had was the factory TB one... and a lil ripped coupler which is fixed! :tongue: I am clamped at 4.7v and again at the certain spot (4800RPMS) maybe a lil bit after it drops to 3.9vlts.

My mods: Stage 1 PCM & Injectors, AGP WGA, AGP Direct FIt FMIC, SAFC II, Full 3in. Exhaust (MaxxFab REE), SRI (K&N FPIK), MSD 8.5MM wires, NGK 4306's ACT Clutch and LC1/XD1 wideband.

Any thoughts guys? I am all outta them... Here is my maps for my AFC:

NE-PTS
800RPM: -4%
1200RPM: -2%
1800RPM: -2%
2400RPM: -5%
3000RPM: -8%
3600RPM: -8%
4200RPM: -8%
4800RPM: -4%
5400RPM: -1%
6000RPM: -0%

Throttle PT
Lo: 10%
Hi: 40%

Dec. Air
THR: ****%
Ne1: 10%
Ne2: 10%

Thanks, Jeff
i can see your problem in yhour settins, first of all the way the safc clamps is by taking fuel away, u are barely taking fuel away afater4800. what is ur a/f you should be able to take more fuel out even @ red line.


ed
 

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Discussion Starter #10
Your pulling a good bit of fuel out where the turbo is at full boost...then your dropping off considerably in your upper RPM's. What's your A/F read in the upper rpms (4300 and above) I'm guessing your reading pretty rich, and your retarding timing up there.

I'm pulling 10% out even at 6000, there is no way you can be running lean up there with your mods
 

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dsmlights said:
i can see your problem in yhour settins, first of all the way the safc clamps is by taking fuel away, u are barely taking fuel away afater4800. what is ur a/f you should be able to take more fuel out even @ red line.


ed
The reason why I am not pulling fuel after 4800RPMS is because it leaned it out real bad 12's and up! So by putting more fuel in I richened it up a bit! i dont know how to keep the clamp level through out the RPM band with keeping the boost I want the AFR I want 11.5 ro 11.8 redline!

? I hate tuning... :rofl:
 

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Discussion Starter #12
I cant believe your running lean up top with S1 and 75 psi FPR....I'd hate to see what your A/F's were before the FPR install. Just doesn't make sense to me
 

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EssArTee-4 said:
I cant believe your running lean up top with S1 and 75 psi FPR....I'd hate to see what your A/F's were before the FPR install. Just doesn't make sense to me
Before FPR mod my AFRs were perfect... 11.5 all the way across and right before redline they hit 11.8. WHen I installed the FPR unit it hit 10.4 right away the almost immediately went to 11.4 and so on.

And yes it doesn't make an ounce of sense! After work here I am going to be at it again! Any other suggestions? Reset the NE pts maybe? and start from scratch?
 

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Discussion Starter #14
Your saying that your A/F's when leaner after you installed the FPR? I'd say tear it apart and do it over again. Somethings gotta be wrong in there....make sure the relief hole isn't over one of the clips on the inside.
 

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JsSRT4 said:
Before FPR mod my AFRs were perfect... 11.5 all the way across and right before redline they hit 11.8. WHen I installed the FPR unit it hit 10.4 right away the almost immediately went to 11.4 and so on.

And yes it doesn't make an ounce of sense! After work here I am going to be at it again! Any other suggestions? Reset the NE pts maybe? and start from scratch?
reread the safc thread
Low/high settings 20/60

sometimes less boost and more -% is better
a real return line will work better most of the time

helping more then 1 person in one thread isnt very easy ...
 

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Vector said:
wow..... some of you need to take a step back and start over
Explain...
 

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EssAr, as you already pointed out, problem MIGHT be timing...You have two options, cheapest/easiest, lower the boost to 15psi and see if there's any difference in the butt dyno...Otherwise you need to buy a device which will display timing advance...$100 for a laptop based program, $230 for a aero force gauge (show 11 parameters and dataloges) and $130 (I think) for a race tech gauge (timing only, but for more $ you can add additional gauges)...

I've seen two locals go from 20psi to 15psi and noticed a huge increase in the butt dyno...Other cars respond better to boost...It's all trial and error...
 

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Discussion Starter #20
Thanks Bacardi, I'm going to get the TechGauges as soon as I get some additional money to spend to check out my timing. I pulled another 3% on the top end since I started this thread and the car has responded much better since. I just need to get to a dyno to do some finer tuning on the low end
 
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