http://www.timskelton.com/lightning/.../dyno_data.htm

This guy has a lightning but its intresting as he has dynoed his truck after every mod and then charted it all down.

Check it out!

 

Very interesting data, I'm amazed on how much hp was lost with the cold air kit.


Rick

 

dcovell,

That link has tons of info, but I really don't know how to use it as the mods related to the data are way outside of the scope of work I'd be willing to do to my truck.

Thanks for the link, dude.

~DM~

 

I find their data to be skewed. Induction is relative to the amount of air required. They say that the CAI lost power and yes it did, but the size of the pipe is to blame for that. Look at the size of the stock intake tract, its pretty big by comparison. So the CAI is a restriction but at what point? A break down of the numbers may show a sizable increase at a given rpm or rpm's. The that goes back to what is the vehicle going to be used for? If it is going to be a dyno queen then peak and average #'s are what to look for. The holes drilled in the stock airbox showed an increase because they allowed more air into the engine. The Holdener guy said he showed the presence of vacuum in the stock airbox. Well there should be a vacuum in there. the engine is sucking air. The other guy stated that the tests would be more accurate if the hood was closed. That just not true. Driving down the road, the streams of air above and below the vehicle cause a vacuum effect and extract the hot air. True this takes a couple minutes to do after sitting for a period but it still does it. The statement about the single blade throttle body is correct because a near stock engine won't see enough benefit from a freer flowing TB. Most engines are, from the factory, designed to be as Volumetricly effecient as possible. Once you start to change the configuration you get lower VE and then you have to upgrade fuel and airflow pieces. Also Driveline power transfer numbers aren't parallel, as the power increase you don't consistently lose 10% for a manual and 15% for an automatic. Those numbers do decrease with a higher amount of torque especially. More power means you have a greater ability to overcome drivetrain loss. Anyhow this is just my opinion, i'm don't mean to offend anybody on here with this, I just think that the data in some areas is alittle off and in other areas the wording can mislead people. But alot of the data is very helpful. I brought this up so we could discuss it.

 

I need to get my truck to a dyno sometime to see what all my mods have done to it. The problem is when you change more than 1 thing, it's hard to tell what has helped the most and what has just done nothing. Plus the mixing of mods, for example...

If you add an airfilter with no cat back or visa versa it may not make as much diffrence as you are being restrictive with the air coming in or out, but if you mod both then you should see a good result that one could not do without the other.

Also another question is does gearing have anything to do with performance on the dyno. So if I had bigger than stock tires would my HP/torque be less than with smaller tires with everything else the same?

 

Gearing in itself has nothing to do with performance on the dyno because the person running the dyno should input into the computer the gear ratio that you have. On the other hand tires could affect the dyno outcome due to rotational mass. The dyno is designed to simulate your vehicle on pavement so Tires that affect your performance on the street should affect your performance on the dyno. Also, you are correct about your breathing needs, the better your engine breath, both in and out, the more power you are going to see. When you change more than one mod without dynoing, your right you cant tell which is making power and which is taking power, but the combination of one that is taking power mixed with another mod may actually make the one that is taking power, make power. HeHe, did I confuse you with that last part?