Ok Ran The Dyno Tonight

[jabartram]

Decided to run the dyno tonight, 86 degrees, 90% humidity in a closed in garage with no airflow! 4 runs, the last run tripped me out my car shifted into 4th at 127 mph and I let off, shift points perfect at 6000 rpm, air/fuel ran 12 all the way across the rpm range.

[jabartram]

you just have to remember to turn of trac control when running the dyno!

[Naich]

not bad man!

[Youngblood77]

sweet :thumbsup:

[smokinAMD]

Wow. I'm impressed. What were the RPMs like when it shifted into 4th on the last run?

[mfuller]

Seems a tad low.....you have 150HP at the wheels; about 10WHP more than stock. Which equates to maybe 187HP at the flywheel. Don't read the spikes; they are merely shortcomings of a Dynojet. Also, if your A/F ratio is only running 12:1. that's a bit rich - while it may help quench knock, it's hurting your peak power by a few HP. You should shoot for between 12.5 and 12.7:1. Time for some headers.

[jabartram]

shifted into 4th at 6000 and let of the throttle right after 4th gear shift

[jabartram]

ok? how are you seeing 150 whp? help me understand? because if I have spent 800 dollars and only gained 10 hp, then this has been a total waste of time and money

[smokinAMD]

Originally posted by jabartram@Jun 10 2004, 09:29 PM
shifted into 4th at 6000 and let of the throttle right after 4th gear shift
Ah, I was curious if you stayed into it for a bit.

I'm more then just curiuos what the top end on that thing is, well, top end without aero drag.

[loudalero]

Well just wondering if you had a dyno before the computer, so we can compare the two.

[mfuller]

Originally posted by jabartram@Jun 10 2004, 09:33 PM
ok? how are you seeing 150 whp? help me understand? because if I have spent 800 dollars and only gained 10 hp, then this has been a total waste of time and money
Okay, I didn't want to disappoint you, but here's how it works.

You see those spikes in the power curve? Well, those are when the car shifted gears. When that happens, the ICM (Ignition Control Module) goes a bit beserk. The dyno uses a lead clamped onto one of your spark plug wires to get a RPM reading, so when the spark changes dramatically (like during an upshift), it throws the dyno off.

So, disregarding the shift spikes, we see a peak of 150WHP at about 70MPH, which is roughly 5600rpm, which correlates precisely with where the V6's power peak should be. As I said, you're maybe only a few HP shy of where your mods should put you, so don't be disappointed. Even with headers and a larger TB I struggle to see 165WHP. Getting NA power out of these cars with simple bolt-ons (like a CAI and cat-back) just isn't in the cards, and I'm sorry if you were led to believe otherwise.

By the way, you should read the following article....it explains why dyno readings should be taken with at least 2 grains of salt. Is your dyno lying? (http://www.caranddriver.com/article.asp?section_id=4&article_id=8020&page_number=1)

[Oldsman]

too humid of a day to test. with no airflow does really help the CAI.

[jabartram]

OK, Cool, I do understand better, thank you for the explaination, we were having some trouble with the dyno at first, so your explaination is more reasonable, which brings me to my decision, I've been trying to decide on which to go on my car, and so i'm gonna go away from performance, I love my car and I'm impressed with the power it has, but I'm gonna put money to better use on it.

[jabartram]

And thanks for the link to the article!

[Alerosince99]

no torque numbers?

When I did my dyno with headers, cai, exhaust I was at about 159 whp. Although that was with a massive exhaust leak and fouled plugs. Your numbers arent too far from where they should be.

[jabartram]

i'm gonna take a disk over and get all my results as soon as i can.

[StealthAlero]

mfuller is right man, sorry to dissapoint you.

If you really wanna see big gains on this 3400, you gotta go to boost. But remember you didn't have any airflow, thats a decrease right there, next time get some dam fans going, because when you are really at 127mph, your sucking up some might cold winds.

[jabartram]

Ok I called the guy today and he brought me a printout of all 4 runs with hp, torque, air/fuel, and mph but its hard to read to many things on one page but maybe it will give a better idea? I still want to get each run on individual disks, so I can post each one.

[jabartram]

he was telling me today that he wants to take out a part of the wall, and I may buy myself a floor blower fan. and then try it again.

[brim]

max tq at 399.4? am i reading that right

what happened there

[Alerosince99]

That happens when the engine shifts.

Really should go back an have him only do the pull only in 3rd gear. Gets rid of all that static.

[mfuller]

Originally posted by Alerosince99@Jun 15 2004, 10:15 AM
That happens when the engine shifts.

Really should go back an have him only do the pull only in 3rd gear. Gets rid of all that static.
That's kinda hard to do with an A/T car. Even if you can get it to hold third gear (start the pull at about 70mph so it doesn't downshift when you punch it), but you also have to account for a torque converter that isn't locked up.