Rpeck

Okay I hop on the dyno for the first time with this or any car I have ever had, I have a few questions;

First they need me to pull my stock O2 sensor to install there wide band. If I adjust my S-AFC settings for optimal closed loop mode (or whatever mode it is that does NOT use the O2 sensor) will the S-AFC compensate when in open loop (or reading O2 sensor mode) Is there any ill effect on tuning my A/F ratio correctly tomorrow without my stock O2 sensor giving a reading?

Second they want to hook up the dyno machine to read my vacuum and boost levels under all gears and all loads. I assume it is a manual boost level reader. What is the best Vacuum line to tap into for a accurate reading? And do I need like a Vacuum line ‘T’ .. to tap into that line? Will using a ‘T’ have any ill effects on accuracy?

Third what should I shoot for I am thinking from what I have read 11.2-11.5 A/F under full boost. Does that sound right? Also I have a dual stage boost controller if I set it to 11.5 at 13 PSI (2nd stage of boost) won’t the car run really rich at my low stage of boost 8-9 PSI?

Should I run any octane boost gas additives before I go? Or will this give me a inaccurate reading when I am running regular 91 Oct?

On a S4 TPS .. with the very narrow low throttle range .. is it even important to get the numbers dialed in right under low throttle settings? And If so .. what kind of A/F ratios should I look for under low throttle positions.

Should I do anything particular to cool my intercooler or Tranny while I am Dynoing?


I think that’s all for now.

Thanks in advance for any ifo fellas, I will be sure to post the dyno sheets tomorrow once I get home.

Robert

OC_

you got open and closed backwards. Closed is when it uses the O2 sensor.

Rpeck

Ya, I always forget what way is what ... sorry bout that.


but can anyone anwser any of my other questions?

Wankel7

Sounds like you got you self a good dyno. They want to put the wideband before the cat and they want to read your boost levels. That is sweet.

James

Rpeck

Ya, I did alot of research. It's a dynopak machine (I think thats the name, the one made in New Zealand) it's soposed to be the most accurate .. they take your tires out of the equation ... no wheel spin issues, it connects directly to the rear axel. I have to leave at 7Am though .. they are 3 Hrs away. there was closer shops, but not with this quality of setup. The problem is they are a Porche shop ..... they don't know a whole lot about 7's .. so I need to know at the very least how I should tell them to tap into my boost pressure on the manifold, Help!

NZConvertible

During dyno power runs the ECU will be in open-loop and won't be looking at the O2 sensor. Once you're cruising and the ECU is in closed-loop the ECU will be correcting the mixtures based on O2 sensor reading regardless of your S-AFC settings. Don't worry about it. Any mechanic worth his salt will find a suitable line in a few seconds. If he doesn't, the pressure sensor line or the BOV line are both easily accessible and will work fine. The shop should have all the fittings needed to temporarily tee into a line. This won't affect accuracy of the readings. I believe 12.2:1 is the sweet spot for these engines, but those figures would be very safe. Tune it on full boost. At lower boost the airflow will be lower and this will simply be measured by the airflow meter normally. Dyno it as you intend to run it on the street. If you raise the octane on the dyno and tune it like that, when you run with lower octane later your settings may not safely supress detonation. Your tranny will be fine, but heat soak will dramatically affect the intercooler if you try to do back-to-back runs, even with a front-mount. At least a front-mount will be cooled by the dyno's fan though; the top-mount won't get any air from this. See what the shop can do for you.

Good luck, hope it goes well. Let us know how it went ASAP.

Wankel7

You could do a water spray on the intercooler. Hell, just get a spray bottle and fill it with distilled water.

How do they connect it to the rear axle?

Also, if you remove your stock o2 sensor make sure you don't let the car go into closed loop. It will cause the ecu to go into a safe mode. That will cause it to lower the performance of the car i believe

James

Rpeck

Thx for the help NZ, I owe ya one..


Wow what a F-In day! jesus .... it's been a long tedious one .. I just got home and I left at 7:30 am

Anyways .. I got all the dyno work done almost everything went well... had a 3 Hr seback when my gamn throttle got stuck open for the IDSIDE! had to take the whole manifold and throttlebody off on the fly. I will explain more later, and post my Dyno sheets .. right now I am beat, gonna head to my GF's get laid and drink a bottle of Vodka to my head... and pray I'm not hungover for work in the morning..


BTW: 324.6 HP & 9.69 PSI. I could not go higher on the boost cause my damn BOV was bleeding off boost .. and like a dipshit I forgot to bring the washers with me to tighten it up. I only Dyno'ed to 7600 RPM.. cause I fear going any higher .. the motor still only has 1600 miles on it .. but it was still making power strait UP the chart .. it scraes me

Cheers!

Rpeck,

go bring a coleman cooler and a couple of bags of ice.

place the ice over the stock Intercooler with the hood open... that will help a little bit... bring lots of ice... you will be surpirsed how fast a bag of ice will melt.

Cheers!

oh i gess i'm too late.. but damn 324.6 HP & 9.69 PSI

wow..

give the full details of your car.

Rpeck

I think the 324.6 (SAE) was Engine HP .. I will have to look at all the sheets, I have about 8 printed out

I think my top RWHP was right in the high 260's still at 9.69 PSI ... but my top HP was at 7600 RPM's and that was my cut off point .. to was still making power way above that ... and my max PSI was way late also .. I will post a few of the sheets tommorow, I am at my GF's right now .. I sent her to go see if they had spiderman on DvD in In the mena time .. i'm browsing the forum.

I assume they I was still gaining and making more and more pwer so high in the power band cause of the street port.. its a large one, or maybee its the turbo setup. I have dyno sheets that show the A/F and PSI of boost by RPM also. I ot torque sheets and everything .. the guy asked me what i want printed .. I told him for 300 dollars you better use a ream of paper print it all!

LOL

Cheers!

you shuld've asked the guy to save the data points for u on a diskette

Rpeck

Ive got them all on paper... and I could ask him to E-mail all the rest .. But I wasn't sure what format it is saved in .. and if its propriotery; wheather I could use it or not.

reboot

nice numbers, i'm in oakland. can you tell me the name of the shop and where its located? also if you can.. how much did it cost?

NZConvertible

The wheels are removed and the units are bolted directly to the wheels. No it won't, the car will run fine with the O2 sensor disconnected. It doesn't matter on the dyno anyway, since you'll never be in closed-loop on a dyno, as I mentioned above.