bcc333

V8 2005 Mustang GT Premium 4.6L 3V 5 speed AUTOMATIC w/ OD 3.31:1 stock rear end;. 5530 mi. Pirelli (PZERO NERO) P235/55 ZR17 98 W m+s all around (W= 168 mph) (767.5 Rev/mi) 32 psi x4 per door jam; stock throttle body: It is a twin 55 mm aperture; K&N Air charger # 63256 using 93 octane BP/Amoco.
Predator U7140 Performance tune. version: stang_05-8r28 12/22/05 3:14:12 PM then Dynoed 3/24/06 they changed all my Predator settings 278.6 RWHP (137-139 mph) v. 267.6
Shaker 1000. Wt = 3471.846 # + people + gas @ 5.67#/gal.

Atlanta Chassis & Dyno tuned it and changed the Predator settings to the following. estimate 267.6 RWHP changed to 278.6 RWHP ...assuming 76.92% conversion factor this would mean 362.2 Flywheel HP. Now using GTECH Pro Competition upgraded to upgraded Firmware 4.0.1, 12in rollout, 13.915sec 1 gallon; 14.061sec full tank 1/4 mi times


Variable ---------------------Predator Actual
Axel ratio ---------------------3.30 3.31
Tire Revs/mi P235/55 ZR17 98w [168mph] m+s 768 765.5
Cool Fan Hi Spd ECT1 ON 190
Cool Fan Hi Spd ECT2 ON 190
Cool Fan Hi Spd ECT1 OFF 230
Cool Fan Low Spd ECT1 OFF 208
Cool Fan Low Spd ECT1 ON 185
Idle Drive -------------600
Idle Neutral 720
MAF Curve 0%
Rev spd Limit 1 6518
Rev spd Limit 2 6518
Rev spd Limit 3 6490
Spd Limiter OFF
Shft pt 1-2 6034
Shft pt 2-3 6034
Shft pt 3-4 5992
Spk Adv 0% (but looks like +6)
WOT 2k-4k 2.50%
WOT 4k-7k 11.00%



[IMG]local://upfiles/31840/1F9356B3B1B34F579958DE7F06790D8A.jpg[/IMG]

Tik_Tok

Not to spoil your bragging rights, but if you got 278.6 RWHP on a dynojet, you have more like 328.3 BHP, not 360.

bcc333

Tik_Tok --
really wasn't trying to brag but what % (looks like 84.9%) are you using to convert and why that %?

I agree that flywheel HP is probably all brag. All that really matters is 1/4 time...and I make no representations that those times are on a flat track and accurate.

Tik_Tok

Oops, that should be 339.9 BHP

Manual transmission add 15%
Auto transmission add 22%

If it's a Mustang Dynameter (it doesn't compensate for altitude like a Dynojet does)
Add 3% for every 1000' above sea level you are at.

dkano

Those 1/4 mile times should be a bit lower if you're already at 278RWHP, I did 13.34 with 285RWHP and a half tank of gas, with an automatic too. Mine just had an intake an a tune from Brenspeed, not custom tuned at a shop. I should probably get one of those GTech Pros, would be good for practice and maybe get an idea of what my 0-60 is.

bcc333

ok, Tic_Tok is more right.

I called Chris at Dynojet and explained the situation. I asked if there was a mathematical formula they used to calculate BHP (Flywheel) from measured RWHP on Dynojet. He said emphatically NO. He went on to say there are just too many variables (e.g., torque of drive shaft, etc. etc.) to realistically measure. He said I could pull the engine and put it on an engine dyno and get pretty close.

we went on to discuss and he suggested a very rough rule of thumb would be a very efficient engine/drive train would lose 12% a less efficient Mustang would lose 20%. He believes that the 2005+ automatic transmission probably is in the 15%-17% range of loss of HP BHP to RWHP.

therefore:
%------- BHP------ RWHP
88%---- 316.6---- 278.6
85%---- 327.8---- 278.6
83%---- 335.7---- 278.6
80%---- 348.3---- 278.6

Tik_Tok

My stock baseline run last year

05 Manual, GT (stock except for carbon trap in inlet removed, it's supposed to be 5 HP) on a mustang dynameter

RWHP X Altitude Adjust X Manual 15%

239.4 X 1.105 x 1.15 = 304.2 BHP

bcc333

Atlanta Chassis And Dyno uses a Dynojet.

http://dynojet.com/automotive_dyno/index.php