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Hey I am getting my safc2 installed next week and dyno tuned also and had some questions. What are the best gears to pull the spec-v on the dyno? I was thinking 3rd and 4th but don't know. Also I am not sure if I should ground my knock sensor for the dyno tune or not. I used to have mine grounded and recently I put it back for saftey concerns. But I have seen some pretty crazy dyno graphs with knock sensors not grounded. I don't want to have some inconsistent runs on the dyno and confuse the people working there or cause any confusion what so ever. Also I am not sure if that will affect their tunning. If anyone has gottent their safc dyno tuned let me know what you think and have experienced with the tunning and your knock sensor being grounded or not.

Thanks
 

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3rd and 4th are best gears to pull in
and yes, get your KS grounded b4 the dyno if u want consistent results....but hey, if u still feel unsafe with it grounded afterwards, u can just put it back :)
 

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just relocate the knock sensor. trust me i beat the **** out of my car every day and get no knocking. just make sure you run 93+ octane. doing this FREE mod make a world of a difference. i felt it pull alot harder on mine after i did it. trust me you wont regret it
 

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Discussion Starter #4
Yeah I know how it feels with the knock sensor grounded and it does feel better, and thanks for the replies just one more question, do you think the inconsistency of the knock sensor would make their tunning process any different?
For instance if they saw the jumps in the graph would they think that was bad and tune it differently? If so I will definately change it, heck I think I am going to do it anyways, but I just wanted to know for sure if that will affect how they tune everything.
 

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1. Dyno in 4th because this is the closest gear of the 1:1 ratio

2. Do the K/S mod, it's a must! I run everyday with 91 octane, timing advance and k/s relocated and no problems at all. We only have a 9.5:1 compression ratio engine and the chance of knock and really really really minimal, even impossible with 91+ octane gaz.

3. I want to see the dyno chart after, should be interessing with all your mods :)
 

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Lishtimphly said:
Hey I am getting my safc2 installed next week and dyno tuned also and had some questions. What are the best gears to pull the spec-v on the dyno? I was thinking 3rd and 4th but don't know. Also I am not sure if I should ground my knock sensor for the dyno tune or not. I used to have mine grounded and recently I put it back for saftey concerns. But I have seen some pretty crazy dyno graphs with knock sensors not grounded. I don't want to have some inconsistent runs on the dyno and confuse the people working there or cause any confusion what so ever. Also I am not sure if that will affect their tunning. If anyone has gottent their safc dyno tuned let me know what you think and have experienced with the tunning and your knock sensor being grounded or not.

Thanks
4th gear for sure, its the closed to a 1:1 ratio. On the knock, if you feel like it and can do it...experiement. Try pulls with it connected and pulls with it disconnected and see how big of a difference it makes. Mine was NOT grounded and if you look at my dyno you can see the breaks in the graph.....thats from the knock pulling timing. I'm currently waiting to redyno with fresh plugs and a grounded knock, my number should and will improve dramatically I'd think.

I just paid $100 for an hour on the dyno, as many pulls as I needed. I think it took us about 6 pulls to get it right where we wanted it. Just get yourself a nice flat A/F curve between 13-13.5. JohnO really helped me out with the install and tuning.
 

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Discussion Starter #8
Alright, thanks guys that helped me with what to do. I am not sure if the shop I am going to will let me go in there while they are dynoing it and let me remove the knock sensor after each run. I have to talk to them. But for sure if I can't do that I am going to ground it.
Also jpalm I ordered the nology wires and ngk spark plugs with the safc and hopefully I will have those in before I get it tuned so when I get my dyno back you can see if it makes a big difference.
I just need to figure out how to get it up but I am sure someone will help me on here if it is a dyno chart. We don't get to see too many of them. What does everyone think I will be getting ? I was thinking in the high 160 whp and possibly low 170's. . .
 

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I have a question about the whole safc-II thing.....say you tune in the summer when it's 90 degrees out....what hapens in the winter? There's more oxygen in the air, so won't you need more fuel than what you had dialed in for, making you run lean again?
 

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Discussion Starter #10
That is a good question. I was also wondering about how much I am going to have to fine tune this thing when I get it and this is a perfect example. Also can you fine tune it for a bit more horsepower and then change it back to one of the presets afterwords?
 

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I know there's a couple of settings you can save. I'm not sure about the winter since its not a drastic change here in Cali, but you do have a point there. And also it seems that a question wasnt answered yet. What happens if you dyno tune and you dont have the KS grounded?
 

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nah u can jus set the thing to only run hard after certain throttle percentage....car version 2 in delaware is doin one on mine tomorrow i got a 2004 an ther doin the tuning through the whole rpm range but it doesnt kick in till 50 percent throttle so yea
 

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Pugnex: The S-AFC will put offset to the MAF signal but that don't make the ATS (temp sensor) disable and still have the A/F corrected by the ECM itself.

But yes, if the ECM think that there is more air flow entering the engine that actually there is, the correction vs the air temp will be slightly offset too... I've think to that too earlier while talking to OrangeVee on our local board www.npclub.com

And if there is a place in the world that have temperature difference, it's certainly in Quebec. Without humidex or windchill factor, temperature here usualy goes from -30C (-22F) in winter to +30C (86F) in summer :eek:

And I've drove my car at -30C and there is a damn hell difference in performance... God, the 4th pull like the 3th :p

So the best idea I guess would be to use the 2 user presets of the S-AFC-II and make one for winter and one summer and disable it in spring and fall ;)



Lishtimphly: You really got the Nology HotWires :confused: Man I think you've wasted your money on this... They remove the coilpacks over the spark plug and use an high voltage cable connected to the coilpacks relocated appart on a ground bracket. This is completly wrong I think because the wires will create more resistance and diminish the power of the spark. Anyway... You can see the instructions here along with pics:
http://www.nology.com/images/sentraserspecv.gif
 

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Yes, I know that the safc works in conjunction with the MAF....in new england we also have a big temp change....100 degrees in the summer to possibly -10 -20 in the winter.
 

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Lishtimphly said:
Hey I am getting my safc2 installed next week and dyno tuned also and had some questions. What are the best gears to pull the spec-v on the dyno? I was thinking 3rd and 4th but don't know. Also I am not sure if I should ground my knock sensor for the dyno tune or not. I used to have mine grounded and recently I put it back for saftey concerns. But I have seen some pretty crazy dyno graphs with knock sensors not grounded. I don't want to have some inconsistent runs on the dyno and confuse the people working there or cause any confusion what so ever. Also I am not sure if that will affect their tunning. If anyone has gottent their safc dyno tuned let me know what you think and have experienced with the tunning and your knock sensor being grounded or not.

Thanks
I've had my SAFC dyno tuned twice already once for the initial setup, then again with further performance mods, both times I left my knock sensor in and my numbers were very consistent, and I had no problems tuning the SAFC, also all my pulls have been in fourth gear because it has the closest ratio (1:1) in my tranny hope this helps
 

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Discussion Starter #18
Angel: About the nology wires we will see. I am installing them this weekend before I get the safc2 installed and tuned so if there is a difference in the car I will let you know. And if there isn't I will cower in shame and hide in a dark hole until everyone I used to know has died off, (or something to the effect of).
 
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