Another spool thread - boost rise time at 4000 RPM
 

Choose a gear so that car is between 65 and 70 mph at 4000 RPM.
Cruise at just above 4000 RPM, coast down to 4000, then floor it.

The data should look like this:

Setting 0 time to be whatever time it hits 100 kPa, here is sample data format (not actual)

5 psi - 0.2 sec
10 psi - 0.5 sec
12 psi - 0.6 sec
15 psi - 0.8 sec

Jason, are you asking us to submit measurements?

InB4Throttle Response thread!

Please cross post at m.net. I am in for some actual good data though.

Well maybe the data presented this way is more useful.
Boost appears to be a linear rise; it overshoots 15 psi slightly so it's pretty linear to 15 psi.

0-15 psi time:

4000 RPM - 0.58 sec ~68 mph
4400 RPM - 0.48 sec (same gear)
5000 RPM - 0.42 sec

You should its a linear rise? seems to me it would start rising quicker and quicker, anyways I got some data I will post up

Pull #1

Map rpm time
102 3788 3.278
110 3906 3.532
130 4150 3.96
160 4361 4.337
187 4577 4.614
205 4712 4.865

Pull #2

I fixed my loose wastegate and it made a big difference in my 4000 RPM data:

4000 RPM - 0.46 sec

VVT, your boost control system, wastegate spring, and timing will affect the results

0-21psi in just over .5 seconds.
....not a miata though:giggle:

Wont this thread be a little biased depending on turbo and displacement?

So run a gt2554 on a 3 Liter I6 and win this thread then:D

Wow, that would really throw this thread for a loop. I was thinking displacement ranging from 1.6-2.1L not 1.6-7.0......and just to make sure this thread is basically a dick measuring contest, correct? lol Not really relevant except for initial spool for highway racing?

Boost definitely DOES NOT always rise linearly. It depends on the turbo, mani, flow of the motor it's attached to, wastegate, timing....

To a noob like you, yes.
To others, like Jason, no.

If you read through our previous spool thread and glance over the plotted charts with everyones contributed info, you'll find it very helpful since you will see what combo's produce what curves.

Post less.
Read more.

My dick is bigger than yours.

https://www.miataturbo.net/attachmen...ine=1325868179

I tried to help him with this issue earlier...but some shithead keeps unbanning him.

In the case of the data I took above, it's pretty damn linear.

Yes, but in many other cases, he's right imo

Agreed, I was talking about my particular data set.