Originally Posted by ben @ evosport
Yes, but the dyno Tom posted only reflects the gains from SS Headers/Cats and software.
This section of the article was a little tricky, as there was a brief technical explanation as to how those numbers were achieved. Simply stated, ignore the previous gains from Stage I. Uncorrected (SAE), the car made the same numbers prior to Stage II as it did after Stage I was installed--which is exactly as it should be.
If someone has spent the time, effort and money to do the equivalent of your Stage I MOD and NOW they are trying to decide How Much "POP" or increased POWER & OR HP they will get by doing your Stage II Mod, HOW can they ignore what they previously did to their car and what the previous Dyno stats & results were?
Doesn't the Gains that Tom posted include ALL the MODS that were on the car at the time of the Dyno-tuning ... NOT ONLY the SS Headers/Cats & Software?
If I understand this correctly ... The Stage I upgrade consisted of the SS Exhaust, SS X-Pipe, UD Pulleys, K&N Air Filters, NEW Sparks Plugs (possibly Denso Iridium??) and the Stage I Software. Isn't this correct?
Here is where I'm a little confused here. You say I should ignore these previous gains from the above Stage I upgrade. Those gains on the Dyno when the testing was done last October were 345hp to 365hp and 334 ft-lb to 344 ft-lb of torque.
The above set-up yielded 365hp @ 6400rpm & 344 ft/lb Torque @ 4530rpm.
The installed cost for the above described upgrade is approximately $4500.
This info was taken from the EC Mag. article of October 2003.
I don't know if it was ever stated How Many more miles was put on the car between the 2 upgrade sessions.
SO Now ... We ADD to the above described M5 Stage I car ... the SS Headers, SS Cats, New Exhaust Gaskets and the Stage II Software you now have 379 hp @ 6650rpm and 346.4 ft/lb of torque 4750rpm. I can only assume that before this next round of Dyno-Tuning, you gave the car a fresh set of Plugs.
With the addition of the SS Headers, the SS CATS, New Exhaust Gaskets and the Stage II Software you have added a NET Gain of 14 HP and almost the identicial ft-lbs. of Torque from the previous Dyno Session. The approximate cost of this New upgrade is $7600.
Can you Please explain WHY the Stage I MODS and Dyno Session Results should be ignored?
I'm not trying to be picky or difficult ... I just trying to understand "WHY" I would ignore the previous MODS' Dyno Results!