Mustang Dyno's SUCK

[Shannon]

I haven't been this pissed in a while.
97 Cobra....Aluminum Driveshaft and Flywheel, diablo chip, CAI, Magnaflows dumped mid length under the car with no cats, and 4:10's. This thing said my the wheels HP is 240, and a computed time in the 1/4 of 14.8.
I haven't got any real time slips but I've G-Tech quite a few times and my best is a 12.9 at 106.7. I know this thing is dead on because the guy that bought it regularly goes to a track and he gets the same times.
I went off at the mouth a little and the guy said my car, wouldn't even get in the 13's. Dude, I eat stock vettes M6's or Auto's by 1 to 11/2 cars by 4th gear. I know what my car does....Anyways, I found a guy with a very stout GT and ran him right when I left this place, that has a 13.4 slip. He video'd it even and ofcourse, I got him by almost 2 car lengths.
I know these things are supposed to be more accurate and simulate the road but....When driving, the road doesn't have the drag this thing did, I mean you had to shift quick while running it up or it would freaking stall your **** out.
The guy before me, had a all bolt on GT and off his 100 shot, it said he was 198, with it 299. Whatever, I so wasted my time and will never use it again.
Anyone else been through something similar???

 

[stangman]

don't sweat it man, that's the way mustang dyno's are. they are more of a tuning tool than anything & a very good one i might add. if you want numbers get on a dynojet.
a mustang dyno takes in several factors, like vechicle weight being the biggest & the inertia of the dyno is based from that. as where a dynojet has a set inertia to start off, so there for it's not specified to your car, inturn giving you "inflated numbers".
mustang dyno's can be tuned to give you a higher number, but what's the use. the one i go to has roughly a 33% loss. but every dyno is different. btw-i know a guy that dtno'd the exact same hp on the mustang dyno in a 97 cobra with similar mods.

and as for the timed 1/4 mi run, don't even pay any attention to that. there are way more factors in a race, than on that thing

 

[Wicked02GT]

Yeah dude, chill.
Dynojets are the standard so its easier to compare your car when you have dynojet numbers. But Mustang Dynos are load bearing and are ultimately better for tuning.

 

[djtech]

I haven't been this pissed in a while.
97 Cobra....Aluminum Driveshaft and Flywheel, diablo chip, CAI, Magnaflows dumped mid length under the car with no cats, and 4:10's. This thing said my the wheels HP is 240, and a computed time in the 1/4 of 14.8.
I haven't got any real time slips but I've G-Tech quite a few times and my best is a 12.9 at 106.7. I know this thing is dead on because the guy that
...clip...

Anyone else been through something similar???

Like c2see21 said, ignore the 1/4 mi time. I didn't even know they calculated that.

You mentioned stalling and having to shift quick... the shop I went to (Detroit Speedworks) did the whole thing for me. I didn't even get in the car when the dyno was running let alone shift any gears. I didn't notice any stalling but it took him at least 10 minutes to get everything setup before doing the pulls.

I think Mustang dyno's do a good job for tuning (based on what I've read). It does suck you can't go and tell everyone how much rwhp you've got. What you can do is convert your Mustang Dyno #'s to dyno jet numbers by adding 7.5% (higher HP dictates higher %).

Your 240 HP would be around 259 HP on a dynojet. For the mods you have doesn't sound bad to me. If you want to read more on this look here:

old post w/ more info

 

[RealQuick]

Dude, I eat stock vettes M6's or Auto's by 1 to 11/2 cars by 4th gear. QUOTE]

The only C5 vettes you'll beat in your ride is if they couldnt drive. Sorry dude, reality hurts.

 

[CANTONRACER]

I would go to a track and actually quit bull****ing about what it supposed to run. Just like your bud that says he runs 13.4 and you got him...when my Z28 ran 14.0's@99 MPH, I never once lost a race to a 5.0 and every single guy I raced told me they ran mid 13's, hell, one even said low 13's and I smoked them. (Not a flame to the 5.0 crowd...just happen to be the primary car on the street for a long time in my area...I know there are some killer 5.0's).

People bs all the time about how "fast" their cars are...just like everyone at car shows all run 10 seconds or better...yet never race their cars? Just like what your doing.

But I will give you credit because you actually had the balls to find out what your car does, good or bad. Most will never do such a thing because their "500 hp" combo makes squat.

But if you really feel they are wrong...and I would beat they are for what you have and mods.... if your car really does run very high 12's or very low 13's, go to a track and then take the slip back to them. Say since they told you your car should run 14.8's and it really ran a 13.2(let's guess), then their dyno runs were bull**** and demand your money back because obviously their dyno is wrong.

 

[Shannon]

Dude, I eat stock vettes M6's or Auto's by 1 to 11/2 cars by 4th gear. QUOTE]

The only C5 vettes you'll beat in your ride is if they couldnt drive. Sorry dude, reality hurts.

Go s*** a Di$k or something. I guess there's 8 or 9 vette owners out there which none can drive and Im just the **** and need to be featured on SpeedWeek huh?
One was a 2000 M6 which was my friends and I know he can drive. Somehow I feel like Im 12yrs old responding back like you, but............


And for you guys thays belong on THIS forum.... Im way lean and didn't make any power past 4800, It just flattened out and stayed there to 6800. If I go get an adjustable fuel pressure regulator I can richen it up a bit like like right?

 

[Derek@amazon]

dont sweet it man its easy to convert dyno jet to mustang dyno numbers. i work with a mustang dyno every day its 15% oin the HP side and 20 on the TQ side. this will get you pretty close to the dynojet numbers. dont sweet it

mustang dyno's are win!!!

 

[RealQuick]

Go s*** a Di$k or something. I guess there's 8 or 9 vette owners out there which none can drive and Im just the **** and need to be featured on SpeedWeek huh?
One was a 2000 M6 which was my friends and I know he can drive. Somehow I feel like Im 12yrs old responding back like you, but............


And for you guys thays belong on THIS forum.... Im way lean and didn't make any power past 4800, It just flattened out and stayed there to 6800. If I go get an adjustable fuel pressure regulator I can richen it up a bit like like right?

I guess there are 8 or 9 vettes owners out there that cant drive I have seen 96-98 cobras at my track and with bolt-ons they trap 102-103, hardly vette territory. One of those guys is my buddy who has full exhaust (LT's, hi flow cats, catback), timing adjuster (set on dyno), CAI. He dynoed 287rwhp and a little less torque. Hardly outstanding numbers, but not bad. You said you eat stock vettes, well around here stock vettes trap 107-109mph for the M6's.

On top of that, now you say your having issues and not making power past 4800rpm (cobras peak @ 6k), so you'd probably make 280-290rwhp on a mustang dyno if you did peak @6k! Please dude...

My buddy has the 97 cobra that made 287rwhp, and it would be no match for my dad's 99 vette. I have driven both.

 

[97rmcobra]

I guess there are 8 or 9 vettes owners out there that cant drive I have seen 96-98 cobras at my track and with bolt-ons they trap 102-103, hardly vette territory. One of those guys is my buddy who has full exhaust (LT's, hi flow cats, catback), timing adjuster (set on dyno), CAI. He dynoed 287rwhp and a little less torque. Hardly outstanding numbers, but not bad. You said you eat stock vettes, well around here stock vettes trap 107-109mph for the M6's.

On top of that, now you say your having issues and not making power past 4800rpm (cobras peak @ 6k), so you'd probably make 280-290rwhp on a mustang dyno if you did peak @6k! Please dude...

My buddy has the 97 cobra that made 287rwhp, and it would be no match for my dad's 99 vette. I have driven both.

No Match!, becareful I am watching.

 

[djtech]

dont sweet it man its easy to convert dyno jet to mustang dyno numbers. i work with a mustang dyno every day its 15% oin the HP side and 20 on the TQ side. this will get you pretty close to the dynojet numbers. dont sweet it

mustang dyno's are win!!!

How did you come with up with 15 and 20%? All dyno's do vary but like I said above in our HP range it is 7.5%. If I go with the figures you provide my 99 Cobra put these numbers down stock (converting mustang dyno to dynojet):


251HP -> 289HP
265TQ -> 318TQ

Seems a bit much to me. With 7.5%:

251HP -> 270HP
265TQ -> 285TQ

Sounds much more like DynoJet numbers for a stock 99 Cobra to me.

 

[RealQuick]

No Match!, becareful I am watching.

It will take more than those 3.73's you got coming!!!!!!!!!!!! I short changed you 1rwhp in my post

 

[RealQuick]

How did you come with up with 15 and 20%? All dyno's do vary but like I said above in our HP range it is 7.5%. If I go with the figures you provide my 99 Cobra put these numbers down stock (converting mustang dyno to dynojet):


251HP -> 289HP
265TQ -> 318TQ

Seems a bit much to me. With 7.5%:

251HP -> 270HP
265TQ -> 285TQ

Sounds much more like DynoJet numbers for a stock 99 Cobra to me.

Just for reference, my buddy's 99 Cobra vert put down 270rwhp/27#rwtq w/CAI. I'd say your calculations are more accurate (using 7.5%).

 

[Shannon]

I guess there are 8 or 9 vettes owners out there that cant drive I have seen 96-98 cobras at my track and with bolt-ons they trap 102-103, hardly vette territory. One of those guys is my buddy who has full exhaust (LT's, hi flow cats, catback), timing adjuster (set on dyno), CAI. He dynoed 287rwhp and a little less torque. Hardly outstanding numbers, but not bad. You said you eat stock vettes, well around here stock vettes trap 107-109mph for the M6's.

On top of that, now you say your having issues and not making power past 4800rpm (cobras peak @ 6k), so you'd probably make 280-290rwhp on a mustang dyno if you did peak @6k! Please dude...

My buddy has the 97 cobra that made 287rwhp, and it would be no match for my dad's 99 vette. I have driven both.

I am making power past 4800, just 240 where it peaked at. The power band is like a fucing bike for a couple of seconds and then mellows out till redline. Didn't do an A/F graph but my plugs are white and crispy on the electrode after a 100 miles or so. I know this is the problem. Dude what Im puting out should #'s for a stock 97, not modified. I should be somewhere close to 280 at the wheel.

 

[RealQuick]

I am making power past 4800, just 240 where it peaked at. The power band is like a fucing bike for a couple of seconds and then mellows out till redline. Didn't do an A/F graph but my plugs are white and crispy on the electrode after a 100 miles or so. I know this is the problem. Dude what Im puting out should #'s for a stock 97, not modified. I should be somewhere close to 280 at the wheel.

Well, you are close to stock and Iyou should be around 240-250rwhp on a Mustang dyno (which is what you used). On a dynojet you should be in the 270-275rwhp range. Thats the difference between both dynos.

 

[djtech]

I am making power past 4800, just 240 where it peaked at. The power band is like a fucing bike for a couple of seconds and then mellows out till redline. Didn't do an A/F graph but my plugs are white and crispy on the electrode after a 100 miles or so. I know this is the problem. Dude what Im puting out should #'s for a stock 97, not modified. I should be somewhere close to 280 at the wheel.

I'm not sure based on what you said what the plugs may be telling you. Check here for spark plug pics & info. Seemed like an OK page.

Doesn't a stock 97 put out around 260rwhp on a dynojet (240rwhp on a Mustang Dyno)?

 

[Shannon]

I'm not sure based on what you said what the plugs may be telling you. Check here for spark plug pics & info. Seemed like an OK page.

Doesn't a stock 97 put out around 260rwhp on a dynojet (240rwhp on a Mustang Dyno)?

Somewhere between Ash and overheated. The ground part whatever you call it is white and chalky, if you rub it, the white comes off on your finger.
Also while going home this weekend, my top speed is now 130 at 5000 rpm, it won't pull a bit past that. I've been 145 in this thing before, something is seriously wrong.

 

[djtech]

Somewhere between Ash and overheated. The ground part whatever you call it is white and chalky, if you rub it, the white comes off on your finger.
Also while going home this weekend, my top speed is now 130 at 5000 rpm, it won't pull a bit past that. I've been 145 in this thing before, something is seriously wrong.

Did you get a dyno tuned chip or mail order? Sounds like your chip might need some work.

How many miles you have on the car? A fuel filter change never hurts. Is it possible for you to remove the chip and still use the car? I guess your speedo will be wrong without it.

 

[Shannon]

Did you get a dyno tuned chip or mail order? Sounds like your chip might need some work.

How many miles you have on the car? A fuel filter change never hurts. Is it possible for you to remove the chip and still use the car? I guess your speedo will be wrong without it.

I just went over 70K on it. I had the chip installed in OK City but it wasn't dyno tuned. I told him what I had and he programmed it. 99's were the year they started to be able to compensate for gear ratio's with a chip, I had to put a different speedo gear in the transmission. Yea, I think I will pull it out this weekend and see how she does.

 

[CTCOBRAGUY]

This past summer I had my 97 Dynoed on a mustang dyno and pulled 270rwhp and 285tq. All I had at the time was pullies and catback. The guy asked if I had anything else done and said it was the strongest 97 he saw with just those mods. Right after I got off the dyno my buddy's new Mach1 (stock) got on and put down 268hp (forgot what the tq was). I suggest you look into fixing the fuel mixer and go from there. With a chip I'm surprised you're running rich.