dyno done

Got my dyno done. Took 2 pulls on stock tune and 2 after cobb ap. Only 1 cobb was good. I'm still very new to the cobb and what numbers are good. Any help would be good. I can datalog on the cobb but I haven't yet.

Defiantly needed the tune I tihnk. I've been taking it easy on my car since the mid-pipe. Between 5500-6000 rpms my engine was cutting off. Hopefully someone can help me out on a few questions. Why the sudden surge then drop at 3000 rpm? Also in 2nd and 3rd gear I'm getting a surge in the beginning then it drops down. 2nd around 18psi and 3rd over 20 psi. But 5th and 6th stay at 15.5 psi the whole time. Othewise I think the tune looks good to me.

Done on a dynojet
temp: 85 F
humidity: 35%
AFR: tail-pipe sniffer
elevation: 850 ft
5th gear pulls

stock


cobb tune

to me it is a bit lean on the second run..... Im supprised how bumpy the graph is for a smoothing factor of 5. what is the gap on your plugs?

Yeah the AFR's are leaner than I would personally run for a pump gas tune, especially if you run this tune day to day. You could probably get away with running more timing if you drop the AFR to say the 11.4-11.5 range. On my turbo car, it doesn't make more power running leaner than that anyway on pump gas.

I wouldn't be surprised if the car is pulling timing and that's why you have that big dip and the jaggedness of the graph. I assume you logged knock correction?

Did you check the intake system for leaks? I had some vacuum leaks that were robbing me of some power before I ziptied them tight.

I haven't checked yet. I'll have to do some logs on knock when I can. In the process of moving and still taking it easy on the car til I get it figured out. I thought I heard that tail-pipe sniffers typically run 1 pt leaner than the car actually is. Which would put it in the 11.2 range.

I did check some of the intake system but I dont know everything about the car to check and where.

Gap is stock. I think its .030 to .032 but I can't find it. Think that could be the cause if its not? I just read some posts elsewhere that the cobb ap needs .030. Maybe Peter knows better on this.


I'll try data logging some things tomorrow and posting them up.

I'm running one step colder NGK's gapped to .27-.28, the only mod differences I have from you are a DP, upgraded fuel pump and BOV. You probably don't need a step colder but closing up the gap a bit won't hurt.

Try logging again and monitor KR. It could be pulling timing, but that shouldn't make it fluctuate up and down like that.

You still running the stock BPV? The plastic mazda one is prone to leaks and that could cause something like that since it also is reflected in your boost in the first run. Not so much in the second though so maybe not.

Do you ever hit any fuel cut? Is that what you mean by cutting off around 6k?

I take it this is a mazdaspeed 3, I remember jorge telling peter you can run leaner on these cars because the direct injection atomizes the fuel so well but I still think 12.2-12.4 is alittle lean but im no tuner. If this is just the an off the shelf map from the accessport id get it protuned as soon as you can.

Its a map from cobb themselves but I do want to get a protune. Version 1.07 that alot of people run but it looks like people run stage 2 more even without a downpipe and just the test-pipe.

I do have the stock bpv and I do want to upgrade it soon. Could be that. It probably was fuel cut, the car just basically shut the motor down then back up again. And after the ap it didn't do it again.

Here's my dyno for comparison. Looks like our a/f's are close to the same although when I log with my ap they read much lower but that is not a wideband either.

Also, here's a picture of my last log too just for fun

136MPH...that must have been a road in Mexico?

See how this loads. This is what the guy before me had set to log so it may be too much for your screens to see. If all else fails try downloading it or going to this page to zoom in. Sorry guys.

https://2img.net/h/i289.photobucket.com/albums/ll223/golddragonfire/Mazdaspeed%203/scan0001.jpg

knock, fuel pressure, boost and afr's are look pretty good.

why is the throttle position not 100% when you are making 17 PSI??
Yeah those AFR's look better.. odd that a shop's dyno wideband reads wrong though. lol

Might be fun to run you some time Peter.. I think our cars are very closely matched

Hey, I'm always down for fun.

The TP not showing 100% is just a weird thing between the AP and the way it logs from the ECU. I went back to my tuner on this one and talked to a few people and they were all getting similar results.

lol strange. Do you guys change the knock threshhold at all on your cars? I changed mine to a minimum of 1 load since 99% of knock in that range is a false positive.. at least on my car

I've never seen anyone that self tunes on the forum mention it, but it may be something that is only accessible through the Race Tuner version of software that Cobb only sells to shops.

Quote :

Might be fun to run you some time Peter

not trying hijack but can i get in on that? i have never raced your subaru and its always fun to get in new races. me and peter arent too far apart.

fwiw, when i datalog my stang, 77% is WOT.

Yes I was wide open throttle. Not sure why it says 70 some %.

Also the shop's afr was through the tail-pipe. So its coming after the 1 cat.

I wouldn't mind coming down that way and racing a few people too. Always fun even if I lose. Just gotta wait til my girlfriend and I finish buying our house and I get back from Canada fishing.