Massive RWHP Loss On Dyno

[stkjock]

I can't see the images, however 11.8-11.9 a/f is FI territory, not NA. That's pig rich - lean is mean....

 

[Gremlin85]

12.9-13's is richer, I ran 13.8-13.9 afr with my 9.8:1 compression 3v na. So high 12s is decently rich for a na coyote, let alone high 11's.

I can't see the images, however 11.8-11.9 a/f is FI territory, not NA. That's pig rich - lean is mean....

I always thought that too. But these coyote motors run 11.6ish stock. Tuners don't lean them out any further than 11.9. It's been found that any leaner and there goes #8 or the like.

 

[johnnyv8]

I always thought that too. But these coyote motors run 11.6ish stock. Tuners don't lean them out any further than 11.9. It's been found that any leaner and there goes #8 or the like.

I thought they figured #8 out, I also thought the 13/14 5.0 motor where stronger then the 11/12, I'm I wrong?

 

[stkjock]

I always thought that too. But these coyote motors run 11.6ish stock. Tuners don't lean them out any further than 11.9. It's been found that any leaner and there goes #8 or the like.

hmmmm - I'm not familiar with that.

 

[Gremlin85]

I thought they figured #8 out, I also thought the 13/14 5.0 motor where stronger then the 11/12, I'm I wrong?

hmmmm - I'm not familiar with that.

I'm still learning as much as I can about this motor. I'm not familiar on the specifics, but I heard tuners were messing with fueling too much and changing the KR sensors like the 3v's but it doesn't respond the same and cause #8 failures. Every tune I've come across and everyone I've talked to runs an 11.7-11.9 WOT fueling now.

I know nothing about the 13/14 motor being stronger in any way over the 11/12. Just a revised tune to get the 420 hp rating rather than 412. And no piston-skirt oil squirters.

I'm still investigatign my own motor and I will be doing tests and diagnosis to make sure it was only the temperature causign the low numbers. The lowest I've ever seen with these mods I might add.

 

[Kalatrax]

Coming from somewhere that has an average of a 20% SAE correction factor I will say that numbers mean very little. Peak WHP and WTQ are not all there is to it. Where they start building, smoothness of the curve, and how long it can continue to make power in the RPM band is what you want to look at. I will also say that there is no better test than to go beat on it at the strip. After a corrected tune I made 340whp 320wtq with a 21% correction factor that day. My car whomps on 5th gen camaros, stock 5.0's, and stock cobras all day long though.

 

[FAST3V]

Your AFR doesn't make sense to me. Nor the reasoning behind it.

 

[sportinawoody]

My .02 is try an established/reputable tuner and get your lost #'s. Lito comes to mind for a remote tuner. Do you feel any difference in the cars performance ? I mean just on the street.

 

[Gremlin85]

I'll rephrase this...

If you went to a dyno and got a stock reading and then went back a couple months later with mods and a tune and only put down 3whp more, wouldn't you be confused? Even if it was done on a 90 degree day?

My AFR is for a Coyote motor that runs 11.6 stock. All tuning experience suggest not to run leaner than an 11.9. Just going by what works.

 

[Gremlin85]

My .02 is try an established/reputable tuner and get your lost #'s. Lito comes to mind for a remote tuner. He's also a nice enough guy that he would probably tell you where you fucked up because it appears you have somewhere

I've compared to numerous purchased tunes that I have from various tuners. All came up less than what I ended up with. All done back-to-back.

 

[johnnyv8]

I do agree with what a lot of people are saying. Go to the track and see what you trap. It will tell you a lot. I would think with your modds on a nice, cool day, you should be trapping 118, maybe more. I believe I saw a full bolt on 5.0 trap 121, however, thats here in NJ

 

[stkjock]

My .02 is try an established/reputable tuner and get your lost #'s. Lito comes to mind for a remote tuner. Do you feel any difference in the cars performance ? I mean just on the street.

Lito is not tuning 5.0s at this time

I'll rephrase this...

If you went to a dyno and got a stock reading and then went back a couple months later with mods and a tune and only put down 3whp more, wouldn't you be confused? Even if it was done on a 90 degree day?.

nope

here's a similar example:

my car on a MD dynoed 770 with a 4.0" pulley and 19* timing - same model MD dynos 775 with a 3.875 pulley and 20.5* similar time of the year, the exact weather conditions I don't recall. Was I disappointed that the second pull didn't make 800... yes I was, but again, it's dyno numbers...

 

[BruceH]

CAI isn't supposed to do anything with that motor, pretty sure the same goes for the boss intake manifold.

If the difference was between only adding those two mods I'd say no problem based on reported experiences on this site.

AFAIK the #8 issues were due to a few things. The first being that tuners were simply adding global spark and disabling ks because it was pulling spark from the 5* global they added. It sounds like you are going about it the right way, using caution and keeping the ks on and unmodified.

If it were my car I'd try a little leaner while keeping the ks on. I wouldn't sweat the number differences too much provided the motor is still running good. You are building a good database for your car. I find the experimentation and data collection part of developing a tune to be enjoyable.

Have you tried experimenting with vct?

 

[K_Brogoitti]

I agree with Bruce on the fact that intake mods don't hardly do squat to the 5.0. Also the fact that 11.8-11.9-1 is very rich for an N/A tune. I ran 12.7:1 N/A and Lito deemed that as "Safe" and now run 11.2:1 boosted and that is rich for safety. I'd like to see the dyno sheets to see the difference between OEM and intake mods. I agree with trying to run leaner with KS running at full and messing with VCT to see what happens.

 

[rdsx18]

I've compared to numerous purchased tunes that I have from various tuners. All came up less than what I ended up with. All done back-to-back.

I'm in MA too, mind me asking who you went to? If you want a great dyno tune I would recommend going to Performance Dyno, he did my tunes na and boosted and tunes a bunch of cars around here.

 

[kdanner]

Please don't make it as lean as some are saying. For a pump gas car no more than .85 lambda. Don't let the timing go over about 25 up top. Don't use individual cylinder knock.

And don't race dyno numbers. It sounds like you have a performance box or something similar to measure acceleration times. I find that far more useful than a dyno. That's the end goal anyway, to make the car faster. Who cares what useless number comes out of a dyno.

 

[Redline727]

If your numbers were corrected using the same correction each time on the same dyno weather has nothing to do with it. SAE, STD correct to a specific weather condition. it doesn't matter which one you use as long as your are comparing the same correction and it wasn't like below 40 deg or over like 105 or some shit like that when you did your pulls in extreme temps the math doesn't work out properly from what I read. Here in the states SAE is the most common, STD is the old standard but still widely used depending what your optimal conditions could be where you live. Your correction factor will be on your sheet. You can click the link in my sig for my dyno thread and see my numbers and correction and dyno all that stuff if you want. Some locations with cold weather and low altitude will actually correct your numbers down so its not always used to make your numbers look better its to make sure you can compare different runs on different days accurately. Always want to be on the same dyno though. You cant correct for different dynos. The closest you will get is two of the same model dynojets they are supposed to be within 1% of one another because they are not calibrated by the end user. But lets not even get into the different types of dynos. They're not supposed to really be compared to one another. Just stick with what you have been using. They all read differently.

SAE corrects to these conditons: This is the latest standard/average conditions.
Air Temperature: 77F
Absolute Pressure: 29.23 inches Hg
Relative Humidity: 0%

STD corrects to: (these are the probably the most optimal conditions your car will see without it being much colder and gaining more power)
Air Temperature: 60F
Absolute Pressure: 29.92 inches Hg (avg. pressure at 0 altitude)
Relative Humidity: 0%
My dyno was corrected to this but I can see these conditions where I live so I can actually expect to see/feel the corrected horsepower so it's good to know what it was.

Uncorrected is what it sounds like. It uses the exact weather conditions the dyno sees that moment on the dyno. This is common in some shops that have the dyno in a climate controlled area with only elevation affecting pressure. There is a shop here in VA that has their dyno in a seperate room with huge vents pulling exhaust out and fans blowing air back for ventilation and the room has heat and A/C and sealed off from the rest of the shop. It's pretty nice. And elevation is low so pressure isn't an issue. They go uncorrected typically because their conditions are pretty consistent.

A lot of people talk about DA or density altitude that's just an equation for you to see based off of pressure and humidity what the comparable altitude your car is experiencing, it all breaks down to pressure though and how easy your motor can breathe. For example on a shitty hot humid day and depending on your actual elevation it may be like your engine is experiences pressures as if it was 3285 ft elevation even though you're only at 1000ft. But don't get hung up on that pressure is what matters that's what changes with elevation any way and the dyno reads/corrects the pressure.

I would say for you don't get to hung up on the number. Every dyno reads differently. The important thing is that it was used for its main purpose and that is to tune your motor properly and measure gain. In your case I see you probably expected more out of your Boss IM compared to your last pulls with out it. I don't think you would see much from the change in intake. I also believe pulls are done in 5th on our cars and you will want to take up pretty high in the RPM's with that Boss IM to see the gain. I don't have one so can't say much about them. I haven't really justified the cost to gain to do one just yet being NA still from what I read. The thing is you have stick with the dyno you have been using. You may be tempted to change to hop e to see bigger numbers but that wont help you figure out the difference in past and present you are trying to account for if you switch dynos. What dyno have you been using anyway?

I hope this helps clear up corrections and comparisons between dynos. So you can concentrate on seeing if there is an actual problem or not.

 

[Gremlin85]

Good info, but a few things I'll make clear about my mods and car.

2013 GT 5.0 Coyote.

I started off with STOCK numbers of 364rwhp. Then just long tubes STILL NO TUNE at 383. I tuned it with Boss IM and a CAI (CAI does nothing) and got 386rwhp.

I started off with purchased tunes from 3 tuners (remote tunes WITH datalogging). I was still feeling there was more to be had. I waited for HP Tuners to release support for this car and then tuned it myself. I had a good base to work from and went from there. I changed VVCT, ingnition timing, WOT Lambda, torque management disabled on both engine and transmission, speed limiter and rev limiter to 7800 RPM plus a whole slew of other tables.

My purchased tunes had an 11.7 WOT AFR. I leaned it out to 11.9 and from what's been going around in the tuner world, these motors love that AFR. Leaner will get minimal gains.

I have 27 Degrees timing above 6k RPMS. It ramps up from 20 at 3500 RPM.

I went to the same dyno over and over again. It was Enhanced Street Performance in MA.

I feel that will all my mods and the tuning, I should be more than 386RWHP since BEFORE A TUNE I WAS 383.

I'm leaning towards heat issues since it was 94 that day and these cars are just sensitive. I'll be doing some tests on the engine to confirm there is nothing wrong AS WELL AS going to the track to check my times and trap speeds.

I do appreciate all the input. However, I think it's missing the mark on some.

I felt like putting my situation out there because many around me feel there is something amiss including the dyno tech as he has seen better performance from other Coyote guys with similar mods in similar conditions.

I'll leave this be until I find either anything wrong, or it was just a fluke.

Thanks again everyone.

 

[UltraKla$$ic]

Some of yall need to get out of the car while it's on the dyno!!!!!!!!!!!!!!!

 

[Gremlin85]

As per a request, here are my dyno results. My tuned, long tubes, catless, exhaust, intake Boss manifold VS Stock tune with Long Tubes.

Less power tuned.