Check the archives. We had a dyno day in the Bay Area awhile back and a few cars did a dyno with and without the shark injector.

What we found was that some cars didn't increase in horsepower, but some did by about 2-3 horses. The rev limiter was increased for a few hundred RPMs to reach 7000.

Of course, we didn't dyno the cars properly according to Jim C. To dyno an OBD-II vehicle is difficult. I've included a link to Scott Galaba's site giving an explanation on OBD-II Dyno.

I also copied and pasted an email written by Jim C. himself below.

Good luck

I was sent a URL for an article written by Jim Conforti on how to dyno a vehicle. Don't have the URL, but printed the article out. It was dated April 6, 1999. Here is the article verbatim.

SUBJECT: Dyno's and proper SCIENTIFIC procedure

Guys,

Before you let some slick haired dyno-boy take your money please take some time and learn about proper procedure. Especially if you're trying to actually get some USEABLE information.

If you're not testing mods in a BEFORE and AFTER method, don't waste your time and money.. or mine.. having to read the drivel.

The *proper* and *only* way to test something sorta goes like this:

1) Load car on dyno at full operating temp. (i.e. run it around the neighborhood for 10 mins and get everyone a cold GatorAde since it's hot in the dyno room!)

1a) on OBD-II cars disconnect all 4 sensors and clear adaptation

2) Start car and run it for at LEAST 3 mins to get it into RUNNING conditions and not "Start", "ColdStart", or "After Start Enrichment" conditions.

(Yes, kiddies.. if you just start it and run it you can get all SORTS of wild numbers depending upon how many seconds between start and run.. until the NS timer runs out)

[Thats NS = NachStart = After Start]

3) Make at leastTHREE closely (I'll skip the statistics) comparable (called *significant*) runs pre-mod..

4) If you don't get 3 tight runs.. let the car run LONGER before the runs.. sometimes it takes FIVE minutes :( and do MORE runs until you have 3 close ones.. 1-2%

5) Once you have 3 runs, record what you did to get them

6) Average the runs and plot

7) Make the *mod*..

8) Again, warmup the car to operating temp..

9) Repeat 2-6 using the exact same method recorded in 5..

10) Compare the results..

10a) On OBD-II cars.. reconnect the sensors and clear faults

NOW.. GEE.. you have REAL SCIENTIFIC NUMBERS.

And if you're not doing it this way, which takes conservatively 2 hours per car per mod.. then don't waste your time or money at they dyno.. or our time reading it

Jim C