*UPDATE* 4-4-2006

Sorry for the longwait guys.

I scanned the images but they didnt come out that good you really have to put your eyes into it, Anyways here are the links.

Dyno 1 - http://putfile.com/pic.php?pic=4/9312050639.jpg&s=x10
Dyno 2 - http://putfile.com/pic.php?pic=4/9312055911.jpg&s=x10
Dyno 3 - http://putfile.com/pic.php?pic=4/9312064088.jpg&s=x10


3-31-06
Well guys like 2 days ago i went to go get my N/A Scion TC Dynoed, with the following mods.


Injen CAI
Alphawerks Header
CC S-Pipe (Stainless Steel)
CC Full Exhaust With High Flow Cat(Stainless Steel)
Magnaflow Resonator "14
NST Underdrive Crank Pulley

It took me 1 hour to get to the dyno place most of the driving was done at around 80-90mph.

1st Run: 152.4whp @ 6127 RPM & 149.5tq (3rd gear) (horrible wasnt happy at all)
2nd Run: 155.7whp @ 6240 RPM & 130.8tq (4th gear) (was giving up already)
3rd Run: 172.0whp @ 5672 RPM & 158.4tq (3rd of 4th gear cant remember)

This was done at a 4 wheel drive dyno. the reason why i got the 1st 2 runs so low is that it was a hot ___ day and i was driving it really fast to get it to the dyno shop. Now for the 3rd pull we turned off the car for a good solid 15-25mins getting cooled with the fans they had there.

 

wow... that really puts me off trying to mod the car for speed even with a full I/H/E and the addition of an underdrive pulley, it doesn't even make it's stock crank horsepower at the wheels under real world driving conditions. it has to be cooled down to get anything out of it. How often do we turn on the car and get directly into a race? hardly ever... I'm more interested in the numbers form when you had a hot car. Ah well, that's 4 banger N/A power for ya

 

i actually think those are some pretty decent numbers. esp. the 3rd run but yeh that was from a cooled down car. im assuming ur m/t right? well keep it up!

 

I cant wait to see the dyno sheet. 172whp is crazy!

 

Yes its a Manual Trans. Also the cars temp needle hardly went down when it was in the cooling process. as soon as we started the car back up it took less than 1min to get back to normal temp.

 

The numbers are not bad for what they are....the last run is the number that most stock 2.0l WRX used to have.

 

the whp sounds about right for those mods.. but the torque seems a little low, IMO.

 

Those numbers are all over the place though... I don't know how much I'd trust them - even with the sheet.

I mean the second run, when your HP went up 3, your TQ went down almost 20! That's a huge jump. And the third set of numbers are so far off from the rest of them... like, almost 30 TQ difference?

 

well that is in fourth gear though...so you do lose a little torque on the top end... i would think

 

If those numbers are correct Than you averaged 160whp exactly. I don't think that turned out to be a good dyno day for you. You really need 3 consistant runs to get a good baseline figure.

 

I'd be happy with that dyno, being that it's in florida.

All he has is I/H/E/pulley... which are terrible when compared to the true power-making N/A mods, cams/fuel, ignition tuning/porting, polishing

I'd be satisfied with 160-165whp, which is about what you'd be under "average" circumstances. Not too hot and not a cold start. I'm also pleased with the RPMs of peak, they're right in the fatty of the powerband, so i'd be willing to bet your curve is nice and smooth.

Post them up!

 

yeah, those numbers are a little inconsistent, but as far as power output I dont know what people expect for those mods, those are decent numbers. Poeple seem to think that IHE and a crank pulley adds massive amounts of power.. which is far from the truth. An underdrive pulley helps rpm build more quickly and effects power output VERY little. IHE can usually be expected to add 20 - 30 whp on a 4 banger overall.. on a good day. You cant just add up the individual gains of each peice and think that is the result you get with all three.

I would try to get some consistent runs.. but it looks like yours is doing pretty good! You are pushing 190 BHP with simple bolt ons which is not too bad at all for an NA 4 banger.

 

Thing is, about the underdrive pulley...


If you increase a motor's horsepower, it revs faster and pulls harder, right? While a pulley does nothing for combustion, the car now revs faster and pulls harder from lesser weight... ..


so while we didn't add horsepower, we got the effect of adding horsepower?


(thought experiment.)

 

less rotating mass = a few freed up hp but with the cost of a few ft lbs of trq.

 

Guys sorry for posting so late, i tried to get a hold of other friends to see if they can scan the dynos for me but apparently none have a scanner, so i have to wait till monday so my friend can scan it at his dads place.

Sorry for this, just check back here.

 

You are correct. They increase wheel hp by decrease parasitic losses, thus more BHP makes into WHP. But, the effect of the small decrease in rotational mass of a small diameter object like this is fairly minimal. That was my point.

And as mentioned, you lose system inertia, which means launching suffers just like it does with a lightweight flywheel.. not a ton here so it is not really an issue either.

As far as losing tq, if you lose tq, you lose hp since that is what hp is derived from. When trying to accellerate the engine, you have a lower moment of inertia on the crank with the lighter pulley, so it is easier to rev. Once you are at a constant rpm however, you see more of the negative effect, which is why it is more difficult to keep the rpm up on a launch. So you gain some, lose some as with all mods. The main purpose of a light flywheel or pulley though is to enable faster rpm changes.

 

I am sry, but why did you do any dyno pulls in 3rd gear???

 

because thats the best gear to do a dyno pull in. Please just accept this as fact and don't make me explain the whole GD mechanics behind it...cuz i won't.. i'll tell you to go look it up.

 

where should i look it up??

 

Very informative thread,
https://www.scionlife.com/forums/viewtopic.php?t=104730