DarkBrew

As the title says, this is a repository for Cobb data logs, charts, comparisons and discussion.

A bit of background for my spreadsheet
I've attached a comparison between my car and WCS
Here is a reference to the issues I'm fighting... Start on post 273
https://www.rx8club.com/canada-forum-35/mazdamaniac-dyno-tuning-gta-spring-summer-2010-a-195294/page11/

Both of our runs are on a dyno in 5th gear

I recommend third gear pulls on the street if you can find a good spot to get to redline @ WOT

I'll post some third gear pulls later

Edit:
To standardize log pleas include the following
Time Coolant Temp. (° F)
Equiv. Ratio (AFR)
RPM (RPM)
Calculated Load (%)
Long Term FT (%)
Mass Airflow (g/s)
Throttle Position (%)
Ign. Tim. Lead. Coil (°)
Ign. Separation (°)

9krpmrx8

iTrader: (46)

Damn, mine are all on my laptop, I will post up tonight. Would it help if we all start to log the same things? Maybe even try and log the same way, like do a run from 0-70MPH or something.

fastlaneracing

What should a healthy stock high power rx-8 pull in max g/s in third gear? ~205 g/s?

Just curious.

9krpmrx8

iTrader: (46)

I hit 197 or so near 8500RPMS, not sure which gear I was in though.

RotaryMachineRx

iTrader: (1)

Anywhere between 205-220 seems to be normal... If you click on the link in DarkBrews first post and go to post 273 you'll see that we are logging between 195-197g/s and are trying to get to the bottom of the issue... well I was, my car is now in pieces as I'm installing my turbo.

9krpmrx8

iTrader: (46)

Okay here is a quick shot up to redline from around 5,000RPM from a log I found on my work PC

http://www.flickr.com/photos/9krpmrx8/4990636192/http://www.flickr.com/photos/9krpmrx8/4990636192/ by http://www.flickr.com/people/9krpmrx8/, on Flickr

RotaryMachineRx

iTrader: (1)

Hmm seems like the more logs I see there are only a few people who actually break 205 g/s... I managed to hit 202g/s a couple weeks ago but it was quite a bit colder ambient temperature than previous pulls..... makes me think that we may be off in thinking that 205-220ish is a typical g/s range... wish I would have got on a dyno before installing the turbo.

9krpmrx8

iTrader: (46)

I have hit above 200 as well. i will look at some old logs of mine and grungepups car I have from the Hymee and see what he and I were pulling last year.

RotaryMachineRx

iTrader: (1)

Added my Datalog into my previous post... this may sound stupid but how do I add that image right into my post rather than just an attachment?

fastlaneracing

I helped a friend to buy an used -04 a couple of weeks ago (around 90000kms) it was sluggish because prev. owner didnt floor it enough but it still did around 205 g/s when I tested it before purchase.

fastlaneracing

MFR = 202.60 Grams per Second (g/sec) @ 8200rpm from MMs "Rotary Math" thread.

So a couple of g/s up and down from that should be correct?

RotaryMachineRx

iTrader: (1)

See this is where I wonder what difference a reading of 5g/s or so makes for power and response wise. My car was feeling agile and responsive, but at the same time the low g/s will really only affect your high rpm acceleration.

RotaryMachineRx

iTrader: (1)

Hmm... I never saw that before... maybe when we were told 220 is normal it was a typo or misread and it was meant that 202 is normal

fastlaneracing

g/s can be translated to hp but only as a rough guide. it will change depending on a lot of things.

Have been logging alot this year so it changes, 220 seems to be too high for a stock High Power model? I think above MFR is more correct?

RotaryMachineRx

iTrader: (1)

It certainly seems so compared to most logs I have seen... haha makes me feel alot better about the 197-201g/s I was pulling. The reason Darkbrew was having issues though was because of a pretty low dyno pull at a MazdaManiac dyno day. If you look at WCS' log he made about 197rwhp on the dyno and was logging arojun 209g/s I believe.

fastlaneracing

Correct me if im wrong but these can be used as guidelines for you:

200-205 g/s Stock "231 hp"
220-240 g/s tuned "231 hp" <-- This differ alot depending on so many things.

RotaryMachineRx

iTrader: (1)

I think you'd be hard pressed to see over 220 with NA mods.... but again that is just from the very few logs I have seen. Maybe if porting was involved. I logged max of 201.x g/s with catback exhaust and MM base NA tune on AP.

fastlaneracing

Well im pulling way over that..

fastlaneracing

Missed this part, this is interresting. I was under the impression that my 235 g/s was a bit low for N/A tuned. hehe good thing I belived that because that made me work my *** off with my tuning.

RotaryMachineRx

iTrader: (1)

^ really wow... what mods are you running?

fastlaneracing

Its easier to point you to the european rotary board: http://www.rotaryheaven.net/showthre...zda-RX-8-RS-05

You will find logs, list, mods etc there.

Actually I started a compare logs thread there, feel free to join it. =)

9krpmrx8

iTrader: (46)

Cool.

Flashwing

One thing to keep in mind guys is if any of you have done adjustments to your MAF scaling then using MAF readouts as a direct comparison between cars isn't going to work. As an example, I see between 215 and 220 g/s of airflow at about 9,000 rpms but my last dyno was 185whp.

Without a constant in the measure process you won't be able to make any determinations. Using MAF values on a more general scale can give you approx HP figures but don't get caught up with 5 g/s here or there.

fastlaneracing

^^i agree, my LTFT dont differ more then -1% to max 1%. a good scaled MAF is of course a must before we compare things. and yes a couple of g/s dont mean anything. its differs as the wheater.

Brettus

iTrader: (2)

Mine logged around 225-230 when it was tuned and making 190whp .

Below is some logs I did to measure the effect of a hot engine vs cool engine ...