=0)

 

My vgs install experience.....

https://www.northamericanmotoring.co...ad.php?t=59533

Thanks Andy!

 

I did mine tonight, on an otherwise stock car, instal was little easier than expected hardest par was dealing with the intercooler. Butt dyno didn't notice much felt maybe a little smoother and thought I could hear supercharger at lower RPM, I'm awaiting delivery of a CAI and I think that that is were the difference of this mod being in place is really going to be felt. Thanks to both Andy and LordOfTheFlies for there write-ups I appreciated having multiple views of the same install made every cilck in my brain so I wasn't lost with the car dissasembled, my biggest fear. Also pleased to report that I did not throw any codes, my second biggest fear because AutoZone had closed before I started and I don't have an OBD tool. Total Time was about an hour, of that only 20 min was spent with the IC off the rest was thuroghly studying the how-to's and dealing with those IC boots. Also I didn't realize how much oil got into the IC definately going to consider a catch can now.

 

This morning I really had the chance to open up the throttle when pulling onto the highway, definately felt the difference in throttle response. Thanks agian for the write-ups.

 

i had a look at my tb the other day and saw it didnt close properly .. is this what the vgs is meant to fix??

https://www.northamericanmotoring.co...m/swed_003.jpg

https://www.northamericanmotoring.co...m/swed_002.jpg

 

No that's your throttle body. I think it's not supposed to close all the way (in order for you to idle) but I may be wrong.

 

ok..?

I sorta thought that the pinging was related to the t/b (dont ask me how i got this idea - must of mixed it up with something else)..

 

Did the VGS - very suprised at the results.

Cheers mate for the good work

 

did this this afternoon.... but I'll reserve judgement for the moment. The car certainly comes on boost a LOT harder at about 3300 rpm or so, but between 2500 and 3300 it feels a lot flatter like it's struggling to breathe. It may just be that the transition is a lot more distinct, but I'll report back after a real drive (rather than just laps of my local test track )

 

I did the VGS mod a couple of days ago. I like the results and as an added bonus my ALTA CAI doesn't have that darn high pich whistle @ 3000 rpm cruising on the highway. Wish I would have seen this mod earlyer.

 

I didn't notice the yo yo at all until I switched to a mini madness big bore throttle body. I am not sure why this would happen, unless I have created a vacuum leak when swapping the throttle body. Anybody else have any suggestions?

 

I didn't have the yo-yo either until I switched to a minimadness big bore as well!

After getting the JCW ecu software update, my problem went away.......

 

I have read through all of the pages and don't recall seeing this asked...

Has anyone done this along with the M7 AGS? Not sure why there would be, but any issues with doing both?

Thanks,
JBravoMC

 

i just did this, my first performance mod, yeh! man what a tight squeeze and i lost a IC cover screw, i hate doing that, it always happens to me, i will always lose a screw when the opportunity arises, haha! mine looks just like Andy's, i noticed other people taped into the intake manifold nipple, but that was to tight of a squeeze


i noticed when i took the IC off there was a bit of oil in there, perhaps i will get one of those catch cans.

 

Hey Andy, well I just finished up my VGS today and did something a little different. I saw in your diagram for the VGS setup with all the green tubes, I thought that meant all the green tubes were new tubes but looking back I see you used the same piece of hose that came from the factory when going from the middle connectorto the outside connector. Now when i did it, I just ran new tubing and yanked that old OEM piece out, is this going to make a differnce? First of all, TONS SMOOTHER!! It feels so much better after this mod! Now the problems, I really hadn't noticed any yo-yo in my car but for the first time I did, around 2800-3000rpm with little throttle and also, it does really seem to kick when you let off the gas pedal anywhere past 3000 or so. Can the extra jerk hurt anything? Thanks.

 

Finally got around to reinstalling this the other day. I'd had it on my 2005 MCS auto and had removed it when I was diagnosing another issue.

The boost definitely kicks in sooner and the power curve is more consistent according to my butt dyno. Better drivability alone makes it worthwhile, and better gas mileage seems to be icing on the cake - the on board computer shows about 2 mpg better so far.

 

Does anyone know if this VGS (vacuum routing and benefit) is the same for the automatic?

 

but then, I have a manual, so I'm just talking out my butt!

Matt

ps, make that typing.... But it's so easy to do, and so cheap, that you should try it and let us know what you find....

 

End result would be the same, may have more difficulty with the extra vaccumline making sure you adjust the correct source. May have less oomph at the wheels just because of drivetrain loss.

 

Pays to pay attention to details...

Matt

 

Anyone done a before and after VGS on the dyno to identify changes in the torque curve?

I have a post-change curve from a couple of weeks ago, but I might go back and do some runs without the VGS to compare.

Theo

 

Maybe I should do this while installing my boost guage.

 

yeah you should, instead of using two T's you can get a four-way nipple deal.

 

In the past I have mentioned my odd experience with the VGS...I have done some retesting and the results are similar...The VGS increases inlet temperture dramatically!

The testing environment was roughtly 78F ambient, dry weather, 80mph steady state cruise in 6th and WOT from 4th through 6th.

Subjective observations:

1-With the VGS installed, I noticed greatly improved intitial throttle response
2-Sudden let-off of the throttle results in abrubt engine braking...not sure that's good.
3-Feels like cable throttle...good!

Quantitative observations:

Without VGS installed:
1-80mph, vacume at -4inHg, inlet temperature 135F, outlet 94F.
2-Full boost at 15.7lbs, inlet temperature 185F, outlet 120F.

With VGS installed:
1-80mph, vacume -4inHg, inlet temperature 225F, outlet 120F.
2-15.7lbs boost, inlet temperature 275F, outlet 145F.

I have done this test twice at seperate times after installing/uninstalling the VGS and have gotten similar results. Can someone explain why there is such difference in temperatures?

Side note:

As you can see, there is a greater difference in temps from inlet vs. outlet while WOT as compared to 80mph cruise...I think this is because the DFIC is operating more efficiently as the speed rises...let's just say I was somewhere in the triple digits..."I was testing, not racing officer" (actually got away with that excuse once )

Even more strangely, the DFIC was also able to maintain reasonable outlet temperature inspite of the inlet increases...the readings were beyond 100F difference That one I can't figure out...and yes, I have calibrated my instruments...

 

Bypass valve might be leaking hot boost air back into the inlet. That is the only path for that hotair to get back there isn't it ?