Whats the best gear for dyno runs in the S, 2nd, 3rd, 4th?

Thanks.

 

4th is what i have seen 99% of people making their runs in

 

3rd gear here

 

5th. It's closest to 1:1 ratio.

 

Does it make a lot of difference then with what gear you do the run in, were be running standard diff gears.

I was hoping for a few of the same answers not one of each.

Thanks.

 

Yes, it makes a difference. I believe lower gears actually give lower numbers, but I don't recall off hand. Technically, it shouldn't make a difference, but I guess because of internal frictions, it does.

 

I like 3rd because it's not too fast, not too slow.

Marcus, I don't think it matters which is closer to 1:1. My understanding is that it doesn't matter what the specific ratio is in terms of losses - since they all go through a gear interface, they're all equally "bad." Only if there's a true 1:1 ratio (ie, not going through any gears at all) do you see any benefit.

 

Well, IIRC, at the last dyno day some of the runs were done in 4th and some in 5th (I think on cdelena's car), and the 4th gear runs were lower. However, that could also be attributable to coolant temps, etc... who knows.

 

I thought 4th was closest to 1:1. Thats what I dynoed in.

 

In '00 to '03 cars, 4th is 1.61 and 5th is 0.970, so 5th is closer to 1:1.

In '04 and '05 cars, 4th is 1.61 and 5th is 0.942 so 5th is again closer...

Of course, if you take the secondary reduction gears into account, 4th, 5th and 6th become:

'00-'03 : 1.347, 1.125, 0.940
'04-'05 : 1.402, 1.138, 0.922

So technically 6th is the closest to 1:1.

My opinion is that it doesn't matter, just do it in third. I believe that it's the best duration for dynoing, like I said. If you're looking for the absolute highest numbers to brag about, don't bother with a Dynojet, use a Dynapak that eliminates the rear wheels. Otherwise, if you're looking to tune your car, just pick a gear and stick with it.