Why it's good to put your car on a chassis dyno.

[FoxFour]

So yesterday I go to a local Mustang club event that was holding a dyno day. What that is , is that a bunch of people get together and run their cars on a chassis dyno for the day and have a good time. So, with the little mods that I have on the car I was figuring that I was looking at around 270 hp to the rear wheels. Get on the dyno and found out from the three runs that I made that I was putting out around when the car was stock plus, my torque reading was lower than stock. So I go home and diagnose the problems. Well, one of them is replacing my stock coil packs, according to my chart you can see that there is a little misfire or something after about 5000 rpm's. Second, according to my DTC scanner was that my InterMediate Runner Control (IMRC) system was not opening, which is essentially two plates, one on each side of the bottom of the intakes and has butterfly valves that control the direction of airflow to each individual runner. After 3250 rpm the butterflies open and redirect airflow to the shorter runners which increase upper rpm power. So I essentially have a car that is currently castrated in the upper rpm band and never really knew it until now. So thankfully I can go ahead and rectify the problems. In a sense, it was a good day and a bad day: A bad day because I couldn't get the power that I wanted; a good day because now I can fix it.

[OVERLORD_CHRIS]

i'd like to dyno my car but i know it will make way less then 240hp, so i'll wait tell i eather get twin turbos, or a supercharger.
Hey Foxfour, what type of car you got?

[Wutputt]

A single dyno test isn't really a very accurate indication of how much power you gained (or lost) when tuning the engine. Cause the specs on the sheet of the car are measured on a test engine according to a certain standard (SAE, DIN, ECE, BHP, CUNA, JIS, etc.). For example when testing according to the SAE standard, the losses for driving the auxiliary parts are not counted in.

If you want to know how much power you've gained by tuning, you'd have to do two dyno runs on the same dyno in approximately the same conditions: one when the engine was stock, and one when the engine is tuned. Only then you’d have an accurate indication of the power gain of tuning. So don't draw fast conclusions out of a single dyno run.


But in your case you can draw conclusions, since you know you have a misfire at 5000 rpm and the valves for the variable intake length system doesn't work properly.

[FoxFour]

A single dyno test isn't really a very accurate indication of how much power you gained (or lost) when tuning the engine.

Yes, there are limitations because there are many variables that run into the equation, but it also gives you an idea how the engine is running under load. Personally, I like the Mustang Dyno because it simulates road conditions better than the DynoJet model that I used. In this case the printout that I recieved showed me where in the rpm band it started to drop off, and it really started to drop off past 6000 rpm but even with that power loss I could not feel it even on the dyno, it was that imperceptible. Fortunately, my air/fuel ratio was fine, though running a little rich.
i'd like to dyno my car but i know it will make way less then 240hp, so i'll wait tell i eather get twin turbos, or a supercharger.
Hey Foxfour, what type of car you got?
I own a 1996 Mustang Cobra that has the 4.6 DOHC aluminum block. It puts out 305 hp at the crank stock but with my mods it should be around 320-330 hp. I noticed in one of your posts Chris that you are stationed in Charleston. If you in town sometime I can tell you when the next dynoday the Mustang Club sponsors will be. They do one about every quarter and all makes are welcome.

[adamk24]

If you in town sometime I can tell you when the next dynoday the Mustang Club sponsors will be. They do one about every quarter and all makes are welcome.

So Would they let my bring my Civic by for few pulls :mrgreen:

[OVERLORD_CHRIS]

I own a 1996 Mustang Cobra that has the 4.6 DOHC aluminum block. It puts out 305 hp at the crank stock but with my mods it should be around 320-330 hp. I noticed in one of your posts Chris that you are stationed in Charleston. If you in town sometime I can tell you when the next dynoday the Mustang Club sponsors will be. They do one about every quarter and all makes are welcome.

If they don't mind my Lincoln LS being there, i'll take you up on that offer :)

[FoxFour]

If you in town sometime I can tell you when the next dynoday the Mustang Club sponsors will be. They do one about every quarter and all makes are welcome.

So Would they let my bring my Civic by for few pulls :mrgreen:

I think several months ago someone someone brought their old beater and had it dynoed. Put out something like 80 hp.

If they don't mind my Lincoln LS being there, i'll take you up on that offer :)

As a matter of fact, there was a Lincoln LS there, don't know if it was getting dynoed but I know it was one of the member's cars. They don't mind what kind of car gets dynoed. The place that hosted it was 'PowerZone Performance' off of Remount Rd.

[OVERLORD_CHRIS]

Remount Rd. i suck at remembering street names but i live off of Dourchester, down Archdale, it should be easy to get to, my freind had a 04 Mustang, we should be able to find it.

[gobs3z]

My friends just use their G-Tec to find out if it's faster or not. They run automatics, so you can only blame the car on a slow time. They tune it then run it on a deserted street, and do it all over. It's a lot cheaper that way.

[FoxFour]

I have a G Tech Competition Pro. Around here there are not a lot of places that I can go to that doesn't involve traveling more than 5 miles. I wished I lived in Vegas, there are long flat streets everywhere, not to mention the desert highways. :wink:

[adamk24]

Those Gtech's are actually pretty accurate when compared with other Gtech Runs, however they have a large varriation when compared with chassisdynos. So comparing these two, or more accurately, using a Gtech as a means of getting a HP number to brag about is not a good idea, as the number might be off but it will be the same relative to other pulls. So basically its good for checking what you get from mods, and thats about it. Still good though :mrgreen:

[FoxFour]

Actually it's just a toy to play around with. My father was an electronics technician so I grew up around all types of electronic do-dads, TV's, boomboxes, shortwave radios, scanners;etc. so it was just another toy for me to play with.

[PaulGT2164]

i have a few videos of the miata i built on a dyno, it was fun
the g-tech is neat, but never will be as accurate as a good dyno

luckily i just moved to arizona, so right down the road there are 4 tuner shops with dynos =)
the miata was dynod @ flyin miata in grand juction colorado

apexi has a g-tech like device thats pretty cool

[ace184]

Remount Rd. i suck at remembering street names but i live off of Dourchester, down Archdale, it should be easy to get to, my freind had a 04 Mustang, we should be able to find it.

im chrs' friend w/ the 04. we have a friend at work who has a '70 mustang and went to the last dyno day i believe. he has a 351 cleveland. he just made the mustang and ford magazine to.

foxfour, where u live, i live behind northwoods mall.

[FoxFour]

Remount Rd. i suck at remembering street names but i live off of Dourchester, down Archdale, it should be easy to get to, my freind had a 04 Mustang, we should be able to find it.

im chrs' friend w/ the 04. we have a friend at work who has a '70 mustang and went to the last dyno day i believe. he has a 351 cleveland. he just made the mustang and ford magazine to.

foxfour, where u live, i live behind northwoods mall.

I saw that car, the white one. I live West Ashley, just off Savannah Hwy.

[OVERLORD_CHRIS]

Our buddy brought his car to work, it is dark green I think. Kinda hard to tell at 1am.


I know this has nothing to do with any thing, but we think there is a Ford GT up Jones Ford, my and my buddy are going to see if it's still there.