BW s258 hits the dyno

[T9S1i]

OK, so i finally got to make it out to the dyno. I went to our local "heartbraker" mustang dyno @ full function in union city, ca. (Full Function: Home) Not a dynojet, so dont expect inflated numbers. Cars at this dyno that break 420whp are usually cracking high 10's. With that said...

I filled up my car with 100 octane and I showed up with a safe (rich) tune at about 19psi and i made a baseline run which netted me 301whp/269tq
Not bad!

I had some issues i wanted resolved, the car was running way rich at tip in at about 2600-3000 rpm, also the a/f ratio was not very steady and needed some smoothing out. So the tuner took care of business.

After a bit of drivability tuning, Sean and Dave(pneumo) went ahead and cranked up the boost to 25psi. This netted me 379whp/330tq

Overall im very happy. My goal was to get close to 400hp, and i thought that would take ~30psi. The fact that im 20hp shy of my goal at only 25psi makes me even happier! I know that when i crank it up to 30psi, and tune a bit more i should be well over 400whp and into the 10's. When i add bigger cams and a SMIM to the mix it will be even more fun.

According to the people at the shop, other cars running this HP from their dyno are putting down consistent mid 11 second passes. My friend Dave (pneumo) put down 439whp there and ran a 10.8 on a slipping clutch, just for reference.


As for now, the clutch is on its way out, and i might speed it along by going to race this saturday!
I did two 1/4 mile passes on the way home from the dyno and holy $hit the car is pulling nicely!!! The clutch didnt smell too good after, but it held and i made my shifts so i think i can pull off an 11 if i bring it to the track this saturday.


Mods in profile are up to date.

Baseline is the large dotted line

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Max HP pulls

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If anyone knows how to resize these to a more viewing friendly size, please do and post em up. If not, then you gotta click on the pic when you click the link and you can zoom in.

 

[slowgsr]

hey, what was your timing like by redline on 25lbs with the 100 octane? And do you know your duty cycle by redline on 25psi, how high are you reving?

Thanks.

 

[T9S1i]

Timing is 19* at 8k with a duty cycle of 62%


Just for comparison sake a dynojet will be 15-18% higher so lets take the 15% i would be making 435hp / 380 tq

 

[We're on Boost]

Nice info.
Hey Danny, didn't you put a drive shaft from Drive Shaft Shop on your car about a year ago? I don't see it in your profile. Been wondering how you like it.

The dyno in my neighborhood is a Mustang and I'm a-skeered to go near it.
I'm going to try something a little different. I have a road dyno built into my ecu+. When my engine and exhaust were stock I noticed that with a 21% factor in there for drive train loss the peak hp from it agreed with the stock rating on the car for flywheel hp (you know about 205-210). In other words my wheel hp was about 170 something. So I figure that road dyno is pretty accurate. So I'm going to go with that for awhile and see what happens. Someday I'll probably put it on the Mustang to see how similar the numbers are to my road dyno but you know I don't care that much. With chassis dynos and even engine dynos everybody is forever arguing about how the dyno was "Loaded" and it seems there are other differences besides that. With a road dyno you have the actual on the road load for whatever gear you are in.

Gary

 

[T9S1i]

Nope im running stock axles and driveshaft.

Sounds like a nice feature in the ecu+. I know some people get really accurate estimates in the dsmlink... i didnt, it was closer to what it would be with a dynojet, but not very consistent. I guess you have to be on a perfectly flat road, or tune on the same stretch for it to work and show differences.

 

[We're on Boost]

Yup, road has to be pretty level, and not much wind. And of course if you want to do third gear pulls to redline you have to be someplace where you can go pretty fast - for a second or 2
The thing that makes it potentially accurate is that it is not trying to calculate hp from airflow or anything like that. It is calculating it from speed and time data, from which you can get acceleration, stir in the mass of the car and driver, it's all basic physics from there to get horsepower. Well there's aerodynamic drag - I don't even know if it trys to put in a correction for that. It could possibly because the software is 1st gen DSM specific, not generic.
Really the only thing I don't like about the road pull dyno so far is that the plots look a little bumpy due to, well, the bumps in the road. So I use a big smoothing factor to help compensate but it would be better if the road was actually smooth.
Chris Mellon (Mellon Tuning) over in evom does all of his "dyno" pulls with some logging software called DLL and it seems to give numbers similar to an awd dynojet. I am really not familiar at all with the DLL thing, but I think it is just a logger, not engine management, because he tunes by reflashing the stock ecu - that's actually his specialty.

Gary