I was trying to be a good boy and get a baseline dyno on my G35 auto sedan prior to my exhaust install for the good of all but ran into several problems at the shop.

Those automatic people out there: how did you get a good pull on your G? Below are problems/questions. If you have any thoughts please do chime in.

1. RPM pickup erratic on the loop both front and on passenger side, had to use optical set up which worked fine but is this common? Dyno Man claimed he had same problem on 350Z.

2. Down shifting when standing on it so numbers get messed up. Don't know if there's much you can do about this except gradually build up RPMs.

3. Fifth gear is the one to one gear yes?

4. How to disable VDC/ABS? Isn't there a fuse or two I can yank to totally take these electronics out of the picture? The Dyno Man felt the VDC was still working against him even though it was "OFF" and possibly the ABS too. Does this make sense to y'all? The curve was very shaky instead of smooth and this was his explanation.

5. What should A/F ratio be? Mine was over 14 and I thought I'd been seeing most in the 13s. What is "normal"?

6. Sedan with popcharger, z-tube mods should come out somewhere like 220hp and a little less torque yes? With Stillen your guess is?

I paid for 3 pulls and we ended up doing like 15 pulls to try and get a good number and still we weren' t successful. Dyno Man will redo for free but I would greatly appreciate your successs stories and tips.

Thanks.

03.5 5AT-S (Black-Willow-Premium-Sport-Aero-GroundingGear™-Silverstars-PIAA-PopCharger-Z Tube-Tint-Stillen Dual Exhaust)

 

the 1 to 1 is 4th gear in the auto. Also, the vdc still operates even when it is manually switched off (just to a much lower degree). I think you have to pull the correct fuse to disengage it completely.

Hope this helps. I'm a newb to the A/F thing so can't help you there.

 

<blockquote><font class="small">In reply to:</font><hr>

Also, the vdc still operates even when it is manually switched off (just to a much lower degree)

<hr></blockquote>

Really? Where did this info come from just curious. Would like to see about totally removing it.

"I'm not saying you're full of BS, per se" - Zimbo



-JustICE

 

This has been discussed a while ago. Even one of the car mags mentioned the fact that the vdc kicked in even when turned off (can't remember which.) The only way to truly disengage it would be to pull the fuse. However, the same fuse also controls the ABS, which is something no one should really be without.

 

al503: That jives with what I have read as well. VDC is never totally defeated. I will do some searches on the various forums to see if anyone has posted similar info and how to shut it down.

Thanks for the verification on 4th gear. There was one run in 4th that looked like it had "real" numbers but it was only for a brief range around the 5K RPM range if I remember. I just got the data files so I'll look 'em over this weekend.

P.S. Hope to make it over to the meet as well.

03.5 5AT-S (Black-Willow-Premium-Sport-Aero-GroundingGear™-Silverstars-PIAA-PopCharger-Z Tube-Tint-Stillen Dual Exhaust)

 

I've done a whole bunch of dynos with my car and I assure you that you DON'T need to pull the brake light fuse. You DO need to turn off VDC (every time you restart the car) and make sure your park brake is disengaged.

The only way to do a dyno in an automatic is in manumatic mode. Set it to 4th gear and slowly increase speed to 3000 rpms to prevent it from downshifting. Then hammer the throttle until you get to redline.

--Steve

 

Stve,

He DOES needto pull the VDC on the auto. It is my believe that the AT sedan at least is very finnike (i am sure te spelling is wrong) about VDC. Do the following:

1) Do a 3rd gear run (other gears do not produce an advantage - i tried).
2) Pull the brake light fuse (d-side kickplate) or the vdc fuse (by the battery)
3) With you trany in M mode, place it into third gear, and from about 2500 rpm, engage the dynamometer, use about 80% throttle ot prevent the downshifting into 2nd until 3800 rpm, then apply full throttle, as the tranny will NT downshift ito second passed 3800 rpm. Then you will get some very valid readings passed 3800, which is all you need realyl.
4) Don't worry about not being able to get the low end raeding - it is NOT too detrimental.
5) Your A/F should start out at around 13.5-14.0 to 1 on the low end and richen up to around 12.9-13.1 to 1 on the very top end.

Hope this helps
Gurgen

<P ID="edit"><FONT class="small"><EM>Edited by gurgenpb on 04/30/04 05:29 PM.</EM></FONT></P>

 

gurgenpd.....thats exactly how I did all mine also...3rd gear...build revs to about 3,500 and then....faster till floored .Every time we did one in 4th I got 3rwhp lower

Couldnt afford it when young...gonna play when Im old

 

Well, that's freakin' crazy. I stand corrected

--Steve

 

That is exactly how mine was done.

2003 Blk/Blk Premium w/navigation
Tinted Windows
Chrome Wheels
BRM Catback Exhaust
Injen CAI
Unorthodox Crank Pulley
Clear Corners
Grounding Wires
255/45ZR17's rear

 

start it in 4 and get a high speed/rpm around 80. then you can floor it w/o it dropping into 3rd. A/F should be 13.0-13.1 around that. VDC just turn it off inside the car, you dont need to take a fuse out. But after you dyno your Slip,abs,vdc light will stay on for a few minutes. because your going around 90-100 mph w/o moving and it confuses your car for a moment. Good Luck. i got 215hp--223ftlbs bone stock auto sedan

04 G35 Sedan Blk/Blk
Nissan Badges
Tein S Tech

 

Thanks all for your experiences. Obviously it's possible to get a valid result as you guys have done it.

Gurgenpb: are you saying pull the VDC and brake light fuses or just the VDC with brake light optional?

03.5 5AT-S (Black-Willow-Premium-Sport-Aero-GroundingGear™-Silverstars-PIAA-PopCharger-Z Tube-Tint-Stillen Dual Exhaust)

 

I heard from someone that holding down the vdc button for more than 5 seconds turns it off completely.



2004 G35C 6MT Black. Yes Honey, I promise no mods. I love it just the way it is.

 

DED, if that were true, it would be great. Any more info on this?

Booger, funny you should say, that's exactly what I was getting 3-4 hp less in 4th gear.

Geeman.
Pulling the brake light fuse (believ it or NOT ) deactivates EVERYTHING (brake LSD, VDC, and ABS). So just pull either/or not both fuses - they achieve the same result. Precaution, if you pull the brake fuse while you are in Park, you will not be able to shift, so make sure you are in Neuteal before you pull the fuse. It's a pain in the ***, i know. That's why I made a switch with an inline fuse just under the VDC switch (see above)

Gurgen



243494-Picture(6).jpg

 

Thanks Gurgen. That makes sense now. WIth all your mods I imagine having the inline fuse is much more convenient. I'll be calling the Dyno Man next week. Unfortunately I did not get a baseline prior to install because of my problems but at least I can add to the data points with the mods I have.

03.5 5AT-S (Black-Willow-Premium-Sport-Aero-GroundingGear™-Silverstars-PIAA-PopCharger-Z Tube-Tint-Stillen Dual Exhaust)