Tuned my SAFC2, found a few more hp
 

After I got the headers and lost hp, I figured my tune was off pretty bad so I recently got a SAFC2. I went to the dyno today and tuned it, and the gains were pretty good. I was way lean, surprised I didn't blow it at the track before. I also tried out an electric exhaust cutout, which I welded in right after the headers in the test pipe. OMG, it was so loud. Dude said it was one of the loudest things he has ever heard. He said it sounds like an F1 car at WOT. I think it is just loud as hell, but it was worth it for the track.It was 6hp and 2ft-lbs more when opened versus closed. Alot better than I thought, since I have a b-pipe and straight thru muffler. I guess the non-mandrel b-pipe is a restriction.
Here is my graph from today showing the difference from the SAFC2.
http://memimage.cardomain.net/member...67_14_full.jpg

thats probably the 2nd highest N/A hp for a 4th gen.

darn impressive. The numbers you are making with the dump relieves my fear of running a short 2.75" catless exhaust on my track car.

amazing #'s from boltons and minimal tuning

what was your before and after A/F ratio ie how much did you lean it out

read my first post.
A/F before was 14-14.5 to 1. We tuned it by adding fuel to make it 13 to 1.

Wow thats lean. Your car was probably actually pulling timing because your were getting a little detonation.

Now I can see all the NA guys running to buy an SAFC. I remember when people said it wouldn't do much for NA applications.

I was planning on getting one before this but it does give some hope. my car runs really rich so i am hopping to lean it up a but and pick up a couple hp.

Nice numbers and good looking curves, (no pun intended) Makes me think about b pipe options now for both my cars. Pretty lean there, quite scary considering you went to the track numerous times before running lean.

Thanks...lol. I knew I was lean, but I didn't think I was that high. I am glad I tuned it now, even though the gains weren't huge. I ran at the track alot, and was never as consistent as before, guess the engine was getting freaking hot. It should be more consistent now. I would say that I will drop a little time at the track, but my mph may not go up anymore, I am hitting the rev limiter in 3rd gear as I am crossing the line. It might be time for some slicks anyway.

Definately get slicks. Neal ran 13.43 at only 102.3 mph. So you probably got mid-13s in it, like 13.6.

Hey sleeper, can you post pics of the cutout, any issues with it being too low? I know how loud it can get, I ran my car with only a ypipe on for a week on the street.

A/F Ratio?
 

What are you guys using to get your ratio, just the Dyno results? I was looking at a A/F guage but is it accurate enough? Or is it best to just use the A/F when dynoing?

Sleeper, very NICE results!

Looks like it.

Nope. You need to use a wideband 02 sensor and monitor. Same type that the dyno users have.

There is one cutout picture on the second page of my cardomain. Yes it hangs low, I have scraped it a few times. I will fix it eventually.

http://maxima.cardomain.com/memberpage/494867/2

Just a suggestion, but I'd move the wires out of the path of the hot exhaust when open, ie other side of cutout.

Also, are those wingnuts locktited or anything?

Is Locktite going to stand up to that kind of temp? I've never thought about it until now, so I figured I'd ask...

Not the red Autozone stuff probably, but they make different Locktite versions for EVERYTHING.

Hell I've seen it used on turbine engines and they get HOT.

That's what I remember seeing on some specific parts of the Allison T56-A-427 turbine, but I thought it was green and blue. I know it was Loctite brand for sure (when I was in the Navy), but I don't recall the exact specifics...

I guess I could just check their site and ask their tech support :gotme:

I pulled the cable down to get a good picture of it too, its not in the way at all. The wingnuts are locktighted on. I will replace them soon with real nuts. I left them on there and carry the block off plate in case it messed up in the beginning. I didn't want the wiring to fry, and get stuck with cutout open.
I actually have an in-car video of two WOT runs, one open and one closed. The video footage sucks (camera is pointed to nowhere), but you can hear the audio really well. I am not sure how big it is, but if someone wants to host it I will find it when I get home.

OT ever work on Nukes :hide:
http://memimage.cardomain.net/member...13_18_full.jpg damn cardomain .. :D

Back On topic ... Sorta scary knowing the JWT is that lean in the higher rpms. Where did you get your safc from? Do you use it as an everyday driver now, if so do you adjust for everyday use or just use as is (~13)

Since we are on the subject:

1) NE1 use the really old knob style safc with success?
2) When buying one, are they all the same or does one have to buy a maxima specific unit?
Sorry for the ot crap

It is not my every day driver anymore. I only set up one set of parameters in the SAFC, so it stays that way all the time. I am not so sure that the JWT is that lean for everyone, but I have alot more breathing mods than most N/A people. The older SAFC is fine, it just doesn't offer as many rpm settings to adjust. There is no maxima specific unit, they all wire the same depending on the car. I got it new on a group deal from the spec-v forum, you can get them cheaper on ebay, but I wanted a USDM version with a warranty.

Ok, I checked the video, its 20.9 mb if someone can host it. Its really not that good of a video, but you can hear the headers + cutout pretty well.

Wow man that is really low. I want to install one myself real soon. Got any suggestions on how to make it not be the lowest part of my car?

now based on your cutout results I installed a very short exhaust on my racing Maxima. I used a test pipe I had laying around. Cut it in half, then ran a straight pipe back to the bend before the gas tank and then took it straight out the side. Sounded great, but killed my low end. I ended up putting a turbo muffler where the resonator went and it seemed to fix the issue, and still sounds good. Just wondering how you got such results with the cutout.

Didn't you say it was 2.75 or 3 inch? That is too big for a N/A maxima. You have to maintain exhaust gas velocity to make hp, too big lowers the velocity. I have headers flowing into a 2.5 test pipe, and then the 2.5 cutout, which maintains high velocity, which makes power. With the right size pipe, zero backpressure is the best. It also may be that with a cutout, 100% of the exhaust does not come out the cutout, some of it flows through the exhaust, which may aid in some backpressure to keep from losing hp in the lower rpms. How did you know you lost low end, did you dyno or go to the track?

I went with 2.25" based on the dissent of others. Like I said, now it seems to be fine. I am just waiting to see what it does at the track.

well i had started a thread about tuning of this exact sort not long ago, so i'm gonna run out and get one reguardless

is there any other ways besides a dyno to tell if your car is running lean? Would it act differently?

Pull the spark plugs....

Ditto - Is everyone still in agreement that a V-SAFC is okay.. I want the VTEC activation output for the MEVI ?