Dynamometer

kc2005ptgt · Post by **kc2005ptgt** » Wed Aug 15, 2007 10:31 pm

I am going to get another dyno run this weekend, but here is one question I need to ask...

What gear do you run it in? I had heard fourth for our cars, but then I had read elsewhere to do it in 3rd...

My car is (of course) an 02 ACR, so it has the 3.94 -

3rd gear: 1.36
4th gear: 0.97

I was told to run as close to 1:1 as possible

I dunno, most the info I have is from reading the interwebnet and here and there. Someone school me?

MoxHair · Post by **MoxHair** » Wed Aug 15, 2007 10:40 pm

ragek23 · Post by **ragek23** » Thu Aug 16, 2007 12:12 am

^ when I went to bristol dyno they said anyone that asks what gear to dyno in doesn't know what they are talking about. Aparently the dyno and computer automatically calibrate no matter what gear you are in. I had pulls done in 2nd,3rd and 4th. all had the same results.

MoxHair · Post by **MoxHair** » Thu Aug 16, 2007 5:58 am

I had Runs done in 3rd and 4th and had different results. The Runs in 3rd gear were higher by a few horsepower than the runs in 4th,

dysphagia · Post by **dysphagia** » Thu Aug 16, 2007 12:36 pm

it doesn't matter what ratio you are, the dyno can tell your engine speed, and wheel speed and then do the math. some cars like 3rd more than 4th but thats mostly due to the load level. some cars will pull a lot of timing in 4th due to the higher load.

kc2005ptgt · Post by **kc2005ptgt** » Thu Aug 16, 2007 3:06 pm

which is what mine did, I think I am going with 3rd this time...

quicksilvr · Post by **quicksilvr** » Thu Aug 16, 2007 8:18 pm

3rd ftw

kc2005ptgt · Post by **kc2005ptgt** » Sat Aug 18, 2007 3:23 pm

well, here are the results...

3rd gear, it was about 98 degrees outside today, and I did this almost immediately after a 35 minute total car ride

But either way, I was happy with the results... better than I expected, and given the other factors, I think I did pretty well.

143.58hp/126.09trq --- not bad!

MyNeonSaysHi · Post by **MyNeonSaysHi** » Sat Aug 18, 2007 5:06 pm

Yeah it was pretty hot out, and all those Cobalt SS's didn't help either.

I wonder how much that is to the crank?

I noticed the car sounds ALOT differently with bigger piping and the longtube header. Sounds like a race car when I was behind yah! But damn!!! When that cutout was forced open it was soooooooo loud. My feet were vibrating! I bet the decibel rating was pretty high! Looks like it scared off ALL the Cobalt SS people.

Congrats!

kc2005ptgt · Post by **kc2005ptgt** » Sat Aug 18, 2007 9:32 pm

yeah, once the cutout opened, the colbalt ss guys took off!!! Even Chong mentioned it "scared them off"

On a side note, the electronic cutout does not work

so now I have ordered a new block off plate, I will take off the QTP and put on the block off plate and then see if I can fix this dumb cutout

I am so pissed.

MyNeonSaysHi · Post by **MyNeonSaysHi** » Sat Aug 18, 2007 10:46 pm

Thats the mod life for yah.

Where did you order your EC at? It was new right?

03blackrt · Post by **03blackrt** » Sat Aug 18, 2007 11:19 pm

^ From me....

It was working perfect for me. I don't know what could have happened.

I would guess maybe the fues blew from holding the switch too long or the set screw betweenb the valve and the electric motor came loose? That's the only thing that coes to mind.

On another note, the curves on your dyno are awsome

Although I would have expected more power.

kc2005ptgt · Post by **kc2005ptgt** » Sun Aug 19, 2007 12:46 pm

I expected only about 145hp 130trq, so I am satisfied with it

Plus, it was 95* in there, and 23% humidity, the car drove for almost 35 minutes before I had a chance to dyno, no cool down time, blah blah blah

I say it is pretty good. And on a side note, I am still going to be modding my car

I told MyNeonSaysHi that if I did not break the 140 whp mark, I was quitting modification, and just waiting till I can buy an SRT4

As for the thing being broke, it worked fine for the first week, so I am thinking I over torqued it -- no worries on your part, totally mine. I am removing it to see if I can fix it, so if not, I will chalk it up as a lesson learned and money lost

No worries, mate!

ragek23 · Post by **ragek23** » Sun Aug 19, 2007 1:46 pm

considering all the conditions that was a great dyno!

kc2005ptgt · Post by **kc2005ptgt** » Sun Aug 19, 2007 10:17 pm

Megasquirt will really help free up some power (or find it), and I want to do either 1gn DOHC pistons, or some nice 10.5:1 Pistons and forged internals. I also want to do the windage tray and crank scraper, as well as a lightweight flywheel and clutch (to free up some more rotational mass) and hopefull put down some better numbers, in the range of 160+ -- I also want some more torque! What makes more torque???? I know, stupid question, but I really would like to know how to make more torque on this car as well as power.

03blackrt · Post by **03blackrt** » Sun Aug 19, 2007 11:29 pm

kc2002acr wrote:I also want some more torque! What makes more torque???? I know, stupid question, but I really would like to know how to make more torque on this car as well as power.

More displacment, more compression, longer rods.