Hi All,

I recently purchased a 2005 911 S. I have scheduled to have the GIAC performance software and IPD Plenum installed this week at a local shop that comes highly recommended (GMG). Does anyone have any experience with these products? I've read through several old posts (this is a wonderful forum by the way) and haven't found anything negative on either item. I'm wondering if there is any information some of the forum veterans may direct me to, or preferably, share their own experiences.

Cheers!

 

Here is a large Plenum review, make your own choice.

https://www.6speedonline.com/forums/...ss-plenum.html

As for the GIAC flash, I had one on my first car, and cannot tell the difference from stock to flashed. I have also had a number of flashes on other cars, both turbo charged and NA, and IMO a flash on a NA vehicle is a total waste of money.

 

You`re exaggerating here. May be it would be less noticeable for me if I would have 'S' car with sport chrono - but in my regular C2 after softronic flash difference was like night and day. Totally improved throttle response, more torque in mid-range and higher cut-off point. Plus you get proper tune-up for 93 octane gas.

From my own butt perspective after flash car went from dull into rocket. Same was told to me at latest auto-x - very nice constant pull at entire high revs area up to the very top, very controllable pull without any deviations, heckload of power. If our auto-x chair complimented it it means it should be OK at least.

PS. About plenum - it definitely did not do anything worse on my car as I would notice that right away. As I did not dyno car after installing it I will not say if there were any gains or not. My subjective feeling was that car improved a bit, but it is subjective. If anybody is not financially stretched I see this plenum as a very nice mod - build quality is superb and design is good so by design itself it cannot make things worse. Compliment it with BMC oiled filter in stock airbox.

 

Well, $1K is not going to affect my wallet in any way. Speaking of all mods I`ve done so far power wise it was most noticeable one, believe you or not. And price wise it is much more bang per buck than paying for 'S with button'.

 

The S has more then the Sport button, the brakes are bigger, the engine is bigger, yada yada yada, we all know the differences. The point that you make about it being the biggest improvement doesn't surprise me, a Plenum and a muffler, aren't going to give you any improvements either, so of the three most likely your Softronic made the biggest difference. If you want to improve the performance of these cars, I suggest suspension work, and if it is straight line power, do high flow cats and a LWFW, then you will notice your car being a little quicker.

But as I stated, this is just my opinion

 

Software makes sense to tie all mods together, other than that I would leave it alone. You do an X51 CAI, X51 intake manifolds, throttle body, headers and cats I would say software could help in solidifying any gains. Actually with the X51 intake manifold you would probably need software as it gets rid of the dual plane intake of the non X51 and you would need a tune geared toward an X51.

Going back to the OP though...GIAC of all the software is the one I would never do. It is much to generic...

Dave

 

Hhheeerrreee wwweee gggooo aaagggaaaiiinnnn!!!!

 

I had GIAC done recently, I returned it after 2 weeks! No improvement noted. I did recently get the Plenum, EvomSit ECU, BMC filter & I did notice a good difference. Contact Bryan at RSS, good team!

 

Point being that a flash could very well change just the throttle tip-in (yes, ala sport mode) and nothing else. It would be impossible to separate real vs imaginary horsepower gains by the seat of the pants.

 

EXACTLY! Let me summarize - your "butt dyno" will feel the difference but the power increase has never been dyno'd.

 

I appreciate all the input and particularly the link to the extensive dyno of the plenum - I hadn't seen that when sifting through the forums. At this point, I'm leaning towards just having headers and a catback exhaust added. More expensive, but at least I know the 20-25 horsepower gain would be legitimate (and not make me paranoid that it's going to breakdown when I drive it, like a supercharger would).

What performance mods would you gents recommend, keeping in mind that it's my daily driver? I'm really only looking for 25-50 horsepower at the most, as anything more than that could become problematic (I regretted several of the mods I did on a camaro I had in college because of the reliability issues they caused).

Also, I received a very friendly private message from Mobonic, but it seems I am too low on the totem poll to reply! Hopefully he will see this post and understand why I haven't replied.

 

i had a 2005 997s manual with full AWE exhaust,plenum,GIAC chip,EVO intake and to be honest i did not notice any gains.

 

Here we go again Mr. Northvan, great job and a great contributor to this board. Always negative comments toward IPD Plenums. I've seen with my own eyes a simple 14rwhp on a x51 '05 Porsche not to mention more HP gains in mid-range

 

And my opinion is - car responds quicker, accelerates faster, reacts better, got more torque in mid-range so overall change was very noticeable immediately on the very first drive after the flash.

 

Mondego: Welcome and I'd tell you to 'hold your horses' on mods but since you've got them scheduled.........

After a hell of a lot of "research" I had the the whole header/cats/exhaust, evoms air intake, and GIAC flash done a year ago on an 06S and could not be happier. One of the reasons I went with GIAC was that you don't have to mail in the ECU. In my case the tuner (in Jacksonville) took the car out three times "tweaking" the flash and it's been perfect, so I'm in love with him too. I read good things about GMG from you left coast guys so hope it works out. (By the way, Ryem3, the shop flushed my brakes for $50 since the wheels were already off.)