I thought it might be helpful for everyone if we could put together a compilation of various dyno results for different exhaust/muffler combinations. ie. CAT By-Pass, Cup Pipe, G-Pipe or a combination, complete systems etc.?

I know it also depends on the condition of your engine & can also vary from car to car, but thought it'd be interesting!

Andy

 

Here's mine-
Taken on a Dyno Jet.
Mods include cat bypass, Gemballa primary muffler, Cyntex chip, drilled airbox w/ K&N,

Also for comparison, I have Escort performance meter times.
0-60 4.88 sec
1/4 13.18 secs @ 108.05
60' 2.03 sec
0-100 10.90 sec

According to Jimmy's ET calculator on www.forcedinduction.com
The DynoJet 254.5hp translates to 216.325hp on a Mustang dyno and with that hp, my vehicle weight of 3260 (including me) and a Cd of .32, the car should run a 12.691 @ 107.64. Also 0-60 of 4.248 and 60' of 1.96 sec.

I guess I have a long way to go on my launches, but not bad for a 15 year old car with 156,000 miles.

 

Impressive 0-60 & 1/4 mile times there for 254 rwhp Colin. The one (and only) time I had my C2 at the track, I could only achieve a 14.10 in the 1/4 mile.

Thanks for the info!

 

If you do a search, you'll find my dyno results. Basically, using a dynojet, I got 234 rwhp with stock headers, primary and a secondary bypass. When I went to a cat bypass I got 244 rwhp. Changing to Fabspeed headers and dual outlet muffler with a chip to push the timing a bit (98 octane gas required) and biased for the more free flow got me 239 rwhp. I'm back to running stock headers with cat and secondary bypass pipes.

 

Not to rain on anyone's parade, here, but to obtain useful information you should use the same car with exact same atmospheric conditions when comparing various modifications. A baseline run would be critical, as well.

I just spent a weekend at the track where the morning qualifying times were a good second or two faster than everyone's best race lap. The primary difference was ambient temp which went from 70 F to 90 F.

$0.02

 

Joey makes a good point. My numbers all came from the same dyno and (the advantage of living in SF) the temperature and humidity was pretty close for all runs (upper 60's or low 70's with about 60% RH).

 

I've had many dyno runs, albeit motorcycles, and they all used temperature, barometric pressure, and humidity(there may have been another) as correction factors. Comparing different modifications on different days should be okay under these conditions. Conditions can change during one day session.

N

 

Dynos do vary greatly in how they read for so many variations. A dynapak, dynojet, dyno dynamics, mustang etc. will all give different numbers on the same car with identical atmospheric conditions. It's a tough one to compare until there is a large enough data base with what to expect on a particular dyno. The most telling information is the curves themselves and not so much the numbers. The overall curve in the graph posted is very smooth; just like these motors feel!