shelbyracer Posted July 13, 2008 Report Share Posted July 13, 2008 I was supposed to take my 427 cobra to the dyno with its new fe stroker. Unfortunately it is not done and therefore not in the car. It was a Nor Cal Shelby event (one of the members has his own chassis dyno) and I figured I could use my FREE dyno time to see what my stock 3,000 mile 08 SGT had. Accounting for 15% loss through the drive line, it should have come out to about to 273 at the rear wheels assuming 321 at the crank. I got a consistent 250 hp at the rear wheels at 6000 rpm which means that I have less than 300 at the crank. Hmmmm - less than a stock mustang gt. So much for the cold air intake and the re-flash giving me an extra 21 hp over a stock mustang. Has any one else had this kind of problem or am I as blessed on this Shelby as I am on my cobra? Thanks. John(;-) P.S. The good news is that a pair of Shelby GT500 mustangs had the best pulls of the day. One, that had a tune put out 430 at the rear wheels and the other that was stock put out 413. Link to comment Share on other sites More sharing options...
hertzworld Posted July 13, 2008 Report Share Posted July 13, 2008 A buddy of mine has a 06 Stage 2 Roush which has more done to it then the Shelby GT and he put down 268 rwhp and you figure in 20% loss not 15 Link to comment Share on other sites More sharing options...
hertzworld Posted July 13, 2008 Report Share Posted July 13, 2008 also the dyno might be off i have seen people run the same car off of 2 different machines and get 20hp differences in them Link to comment Share on other sites More sharing options...
shelbyracer Posted July 13, 2008 Author Report Share Posted July 13, 2008 also the dyno might be off i have seen people run the same car off of 2 different machines and get 20hp differences in them Yeah, the car is still a BLAST to drive (and gets better than 20mpg), I was just expecting more. I almost got some one to run their white 07 sgt to try and get a comparison, but it just didn't happen. 20%....really. If that is true (and I am not doubting you - I just don't know enough myself and have been told by people who I know and trust that it is 15%) that would be much closer. Link to comment Share on other sites More sharing options...
AFBLUE Posted July 13, 2008 Report Share Posted July 13, 2008 I show you have a manual transmission. So yeah, your result are low if it was a dynojet. If it was a mustang dyno then it may be ok. Figure 12-13% drivetrain loss on a Manual Mustang and 18-20 for an auto. Soime SGT Stock Dyno #s Shelby GT #0779 279 CudaFly 281 Ed S #571 276 Ed S #571 280 Lulu 276 SGT#507 275 mastersmech1 285 Mean 278.86 Median 279.00 Lot of SGTs were dynoed down in Cary, NC and they all came in in the 270-275 range. Maybe your running too rich. I dunno. Link to comment Share on other sites More sharing options...
ShelbyDude Posted July 13, 2008 Report Share Posted July 13, 2008 I was supposed to take my 427 cobra to the dyno with its new fe stroker. Unfortunately it is not done and therefore not in the car. It was a Nor Cal Shelby event (one of the members has his own chassis dyno) and I figured I could use my FREE dyno time to see what my stock 3,000 mile 08 SGT had. Accounting for 15% loss through the drive line, it should have come out to about to 273 at the rear wheels assuming 321 at the crank. I got a consistent 250 hp at the rear wheels at 6000 rpm which means that I have less than 300 at the crank. Hmmmm - less than a stock mustang gt. So much for the cold air intake and the re-flash giving me an extra 21 hp over a stock mustang. Has any one else had this kind of problem or am I as blessed on this Shelby as I am on my cobra? Thanks.John(;-) P.S. The good news is that a pair of Shelby GT500 mustangs had the best pulls of the day. One, that had a tune put out 430 at the rear wheels and the other that was stock put out 413. Sounds to me like the dyno is off. Those are low numbers on the GT500's as well. So that is 3 cars showing below average. Has to be the dyno. OH, BTW, the stock SGT HP is rated at 319, not 321 Link to comment Share on other sites More sharing options...
shelbyracer Posted July 13, 2008 Author Report Share Posted July 13, 2008 I show you have a manual transmission. So yeah, your result are low if it was a dynojet. If it was a mustang dyno then it may be ok. Figure 12-13% drivetrain loss on a Manual Mustang and 18-20 for an auto. Soime SGT Stock Dyno #s Shelby GT #0779 279 CudaFly 281 Ed S #571 276 Ed S #571 280 Lulu 276 SGT#507 275 mastersmech1 285 Mean 278.86 Median 279.00 Lot of SGTs were dynoed down in Cary, NC and they all came in in the 270-275 range. Maybe your running too rich. I dunno. It is possible that I am running rich. The check engine light came on a while ago - bad pcm. The dealership had the car for 2 weeks (blaming SAI - which I know is false because Amy was nice enough to give me the name of the person at SAI who could help me / the dealership). It went back to the dealership less than 24 hours later because the check engine light came back on because they had loaded the wrong program and the car was running lean. I suspect that the car is still not right - tail pipe used to be clean, now it has some black soot. Link to comment Share on other sites More sharing options...
shelbyracer Posted July 13, 2008 Author Report Share Posted July 13, 2008 Sounds to me like the dyno is off. Those are low numbers on the GT500's as well. So that is 3 cars showing below average. Has to be the dyno. OH, BTW, the stock SGT HP is rated at 319, not 321 Hey man....whats 2 hp between friends . If the GT500's are low to, well - there you go. Link to comment Share on other sites More sharing options...
LuLu Posted July 13, 2008 Report Share Posted July 13, 2008 Atmospheric conditions can kill dyno results. Humidity confuses the MAF. All the numbers posted here seem low to me, could have been the weather? Link to comment Share on other sites More sharing options...
torquewrench1807 Posted July 13, 2008 Report Share Posted July 13, 2008 I was supposed to take my 427 cobra to the dyno with its new fe stroker. Unfortunately it is not done and therefore not in the car. It was a Nor Cal Shelby event (one of the members has his own chassis dyno) and I figured I could use my FREE dyno time to see what my stock 3,000 mile 08 SGT had. Accounting for 15% loss through the drive line, it should have come out to about to 273 at the rear wheels assuming 321 at the crank. I got a consistent 250 hp at the rear wheels at 6000 rpm which means that I have less than 300 at the crank. Hmmmm - less than a stock mustang gt. So much for the cold air intake and the re-flash giving me an extra 21 hp over a stock mustang. Has any one else had this kind of problem or am I as blessed on this Shelby as I am on my cobra? Thanks.John(;-) P.S. The good news is that a pair of Shelby GT500 mustangs had the best pulls of the day. One, that had a tune put out 430 at the rear wheels and the other that was stock put out 413. I was not happy with my cars results from dyno day, so I later went to another performance shop for a dyno. Below are two dyno results from two shops done on my bone stock 07 SGT. Link to comment Share on other sites More sharing options...
AFBLUE Posted July 13, 2008 Report Share Posted July 13, 2008 Hey tq, do you know the brand of dynos used at Motion Dynamics and Colvin Auto? Also are both your numbers listed in your Sig, SAE corrected? Link to comment Share on other sites More sharing options...
LuLu Posted July 13, 2008 Report Share Posted July 13, 2008 Bone stock SGTs on a DynoJet should reveal 270+ RWHP, and 300+ RWTQ. If y'all got less, it's a faulty dyno test. Bad dyno setup, or, a dyno operator who can't pull his thumb out of his azz. Just my .02C gents, carry on... Link to comment Share on other sites More sharing options...
AstroDan Posted July 14, 2008 Report Share Posted July 14, 2008 Bone stock SGTs on a DynoJet should reveal 270+ RWHP, and 300+ RWTQ. If y'all got less, it's a faulty dyno test. Bad dyno setup, or, a dyno operator who can't pull his thumb out of his azz. Just my .02C gents, carry on... +1 Here's mine from 4th of July. As you can see, I'm running rich.... Link to comment Share on other sites More sharing options...
shelbyracer Posted July 14, 2008 Author Report Share Posted July 14, 2008 Atmospheric conditions can kill dyno results. Humidity confuses the MAF. All the numbers posted here seem low to me, could have been the weather? barometric and atmospheric correction data were input right before I strapped down to the dyno. Link to comment Share on other sites More sharing options...
shelbyracer Posted July 14, 2008 Author Report Share Posted July 14, 2008 I was not happy with my cars results from dyno day, so I later went to another performance shop for a dyno. Below are two dyno results from two shops done on my bone stock 07 SGT. Both are better than mine. Link to comment Share on other sites More sharing options...
shelbyracer Posted July 14, 2008 Author Report Share Posted July 14, 2008 Bone stock SGTs on a DynoJet should reveal 270+ RWHP, and 300+ RWTQ. If y'all got less, it's a faulty dyno test. Bad dyno setup, or, a dyno operator who can't pull his thumb out of his azz. Just my .02C gents, carry on... Hommm... my hp was 250 and my torque was 256. I am seeing 20 - 30 difference between hp and tq. Maybe it is he dyno or the program since I was the first one on that day Link to comment Share on other sites More sharing options...
shelbyracer Posted July 14, 2008 Author Report Share Posted July 14, 2008 +1Here's mine from 4th of July. As you can see, I'm running rich.... If my scanner worked, I would post my graph Link to comment Share on other sites More sharing options...
AstroDan Posted July 14, 2008 Report Share Posted July 14, 2008 I was not happy with my cars results from dyno day, so I later went to another performance shop for a dyno. Below are two dyno results from two shops done on my bone stock 07 SGT. I am not seeing the graphs... Give a listen. I like that! :happy feet: Link to comment Share on other sites More sharing options...
AstroDan Posted July 14, 2008 Report Share Posted July 14, 2008 It is possible that I am running rich. The check engine light came on a while ago - bad pcm. The dealership had the car for 2 weeks (blaming SAI - which I know is false because Amy was nice enough to give me the name of the person at SAI who could help me / the dealership). It went back to the dealership less than 24 hours later because the check engine light came back on because they had loaded the wrong program and the car was running lean. I suspect that the car is still not right - tail pipe used to be clean, now it has some black soot. Sounds to me that the dealer might have "killed" the SGT tune... That would suck! Link to comment Share on other sites More sharing options...
shelbyracer Posted July 14, 2008 Author Report Share Posted July 14, 2008 Sounds to me that the dealer might have "killed" the SGT tune... That would suck! Yeah, especially since I have no recourse. When I brought it back the next day and mentioned that it felt "flat from x rpm and up" the techs comment was - feels fine to me "unable to reproduce". Luckily it did feel better after they retuned it the 2nd time. Oddly, when I was on the dyno, it took my car much longer to go from 3,000 to 6,000 rpm than just about any one else's. Link to comment Share on other sites More sharing options...
AFBLUE Posted July 14, 2008 Report Share Posted July 14, 2008 shelbyracer look at his signature for the dyno numbers Link to comment Share on other sites More sharing options...
shelbyracer Posted July 14, 2008 Author Report Share Posted July 14, 2008 shelbyracer look at his signature for the dyno numbers I saw tq's numbers , I just wanted to post my graph. Astro dan did not see the tq's numbers and was looking for a graph. Link to comment Share on other sites More sharing options...
torquewrench1807 Posted July 17, 2008 Report Share Posted July 17, 2008 Hey tq, do you know the brand of dynos used at Motion Dynamics and Colvin Auto? Also are both your numbers listed in your Sig, SAE corrected? AFBLUE, Both rwhp numbers are SAE corrected. Dyno Jets were used at both Motion Dynamics (MD) and Colvin Automotive. Run 1 at MD: 260 rwhp and 283 rwtq Run 2 at MD: 263 rwhp and 284 rwtq Colvin Auto: 275 rwhp and 294 rwtq Dyno_ColvinAutomotive.pdf Dyno_MotionDynamics.pdf Dyno_ColvinAutomotive.pdf Dyno_MotionDynamics.pdf Link to comment Share on other sites More sharing options...
AFBLUE Posted July 17, 2008 Report Share Posted July 17, 2008 Well that really blows the theory that all dynojets will read the same 12-15 SAE hp is quite a bit different on the same brand. The Colvin #s seem to be more inline with what other SGTs have seen on a dynojet Link to comment Share on other sites More sharing options...
LuLu Posted July 18, 2008 Report Share Posted July 18, 2008 Well that really blows the theory that all dynojets will read the same 12-15 SAE hp is quite a bit different on the same brand. The Colvin #s seem to be more inline with what other SGTs have seen on a dynojet Agreed. Just because someone owns a dyno, doesn't mean they know how to use it correctly. Here's some notes to debate. All the difference in the world stems from where the rubber meets the roller. Above ground Dyno Jets are less accurate than the in-ground version simply from frame flex. Likewise, portable Dyno Jets are even less accurate than the above ground, but many shops use the above ground because it gives the shop another lift to use for other work. Some like to load the roller at 12 to 1 o'clock, others prefer 10 to 11 o'clock. This makes a difference in the results, 11 o'clock is correct. Most precise. Some take care to max out tire PSI as stated on the sidewall, others don't bother, it's "run what you brung". This also makes a diffference in accurate results. Any slip will cost you power. Tired retaining straps stretch and a loose car will not perform as well as a tight car. Ditto for strap location, where and how you tie down the car. Strap tension isn't just supposed to hold the car in place, the suspension should see as much as 25 percent compression, as it would if the car was indeed pushing 100 MPH on the highway. No compression = low numbers. Monitor ambient atmosphere, temps, humidity and barometric pressure local to the dyno site. There can be "bad dyno" days just like women have "bad hair" days. High humidity confuses the MAF as it reads air density as colder temps, and calls for a rich AF mixture. Look at the air fans used at your local dyno. The more air flow, the better. If a dyno is supposed to simulate a high speed pass, air flow has to be efficient to that challenge. The fans are not just for cooling the engine between pulls, they need to simulate air flow at speed. Last...Install a separate .02 bung in the driver's side exhaust down pipe, before the cats. This is the best place to monitor AFR, and your tuner will be able to improve his focus on your tune. Tail pipe sniffers are okay, but a lot of data changes as it is processed by the exhaust system. Here's one to consider. http://www.widebandcommander.com/ My point is not to pump the numbers, but to achieve consistency. This is why I go to the same dyno everytime I want something examined. My dyno dude is very methodical, a perfectionist, and he pays attention to the minor details. New straps every year, best tire PSI, GIANT fans, and so on. No wonder he's so popular in my area. There is one more technology available, and I used it for many years before that shop closed. It's called a "DynaPack", and it takes out all tire/roller/strap concerns. Wheels are removed and the dyno is mounted directly to the drive axles. No slippage what so ever, the car doesn't have to be strapped down, and the equiptment is relatively portable if you are a "heavy duty" kind of guy. You can fit everything in the bed of an F-150, or, store it out of the way in a corner of the shop While I was using it, the DynaPack proved to be very dependable and accurate. Sadly, it's just not that popular...Yet. But, it's coming on fast due to it's accuracy and ability to consistently reproduce exact numbers. http://www.dynapackusa.com/ Gents...Don't be to casual about your dyno tests, this is very important data to have in your hands. Like I said in my first sentence, just because someone bought a dyno, doesn't mean they know what they are doing. After your dyno dude hands you a pretty chart with a lot of aluring lines, ask for the column/row printout. It will be two to three pages long, but it nails down the data every 50 RPMs. Very important stuff to work with when you're building power. Happy motoring. Link to comment Share on other sites More sharing options...
AFBLUE Posted July 19, 2008 Report Share Posted July 19, 2008 Going to get my car dynoed for the first time tomorrow. Just 3 stock runs done on a Australian built dyno dynamics dynameter http://www.dyno.com.au/dyno/controller I will probably go to a nearby dynojet for a comparision of the numbers. Link to comment Share on other sites More sharing options...
SGT/SC#0471 Posted July 22, 2008 Report Share Posted July 22, 2008 Going to get my car dynoed for the first time tomorrow. Just 3 stock runs done on a Australian built dyno dynamics dynameter http://www.dyno.com.au/dyno/controller I will probably go to a nearby dynojet for a comparision of the numbers. AF-that strip of chrome around your quarter windows looks GREAT on your blue car.....! Link to comment Share on other sites More sharing options...
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