It seem like a GTEC should be able to pick up mods that add 20 or more HP. Does anyone one know the sensitivity and repeatablity of GTECH?

 

When it comes to the naturally aspirated 997, many would say that certain mods don't add any power, but I tend to disagree. Each individual part creates the sum. An intake adds some small power gains, and great sound. An exhaust, same. Cats don't add much power, but definitely create an amazing sound. The EVOMSit ECU tune will certainly add some power. Put all these parts together and they create a good package. Each individual part contributes to a nice bump in power, and sound.

I currently have several EVOMS V-Flow intake systems for the 997 in stock, ready to ship, at blowout pricing! If you're interested, let me know.

 

"Have to be careful of butt dyno results - the mind often gets confused and believes you are accelerating and going faster due to the weight reduction from your lighter wallet - it's a quirky thing...

Real dyno or better yet lower lap times are what are really needed IMHO"


Shoot.....come to think of it...I know when I bought my HRE's I swear I picked up 10-15 additional HP......

 

I own the V-Flow and would say that I am glad this is part of my over all package. Maybe it is just the butt dyno, but the sound is amazing and with the right exhaust and software setup, should produce a few extra ponies of performance.

 

I didn't feel crap from the HREs I got, is my butt dyno broken???

 

you are killin' me............

Maybe you should have it checked?........some performance exhaust might be in order?

 

I think the Gtech would provide some objective information. Ideally, it would be nice to have someone baseline a stock car with a gtech, then take measurements after doing various mods, using the same stretch of road, same temperature, etc. to remove as many variables as possible. See Justatoy's thread which is attempting to do this using different members' cars, which of course introduces many variables.

 

I have used the Gtech and managed to get reliable net RWHP numbers.Only problem I see with it,is that it only shows 'peak' horsepower and not the bottom end grunt(curves) that some mods do provide!
FWIW....you really cannot feel 20 or less RWHP BUT the Gtech will !


Stacy

 

I understand that a GTEC will only show peak HP. For the two additional mod I am thinking (I alread have AWE headers) AWE Cats and softech the should show changes in peak HP. Granted the "area under the curve" or gains below peak are more important, if there is no peak improvments I would doubt that any improvement actually occured

 

I agree with you statement!
Another idea for figuring power gains that I use and forgot to mention....is my Durametric software.
As I am running it on my 'power pulls',I am logging data....each piece of data is sampled at certain time intervals along with RPM's.Once the data is collected I can crunch the times by sampling any RPM/time within my 'power pull'.
This with a Gtech help me determine whether my gains are happening and at what RPM range.
Factoring the times within the Durametric doesn't give you the RWHP gain BUT in the long run isn't it all about how fast you get through each gear?!
Faster time=more power
Stacy

 

I honestly believe that best way to see details of any effect from mods is to do pre- and post- regular dyno runs. It is just critical to understand dyno process setup parameters, properly prepare car for it and make sure that any time you do those runs everything is configured exactly same way, same location for all air blowers, naturally same exact dyno shop, preferrably same operator, same fuel, preferably same or almost same ambient temperature and humidity.

If done properly - this way curves will show what has changed on your car. total peak power reading of course has relevance within calibration of this particular dyno only, of course - for that there is Gtech as a reference, but curves from dyno will tell a lot and looking at combination of torque, power, timing and AFR it is possible to see what got changed.

As of speaking of topic - what bolt on mods to do - improving air flow on 997.1 engine is possible and is pretty much doable and from my dyno charts I see perfectly clear how it changed.

 

Based on what I know essentially what we do here with 997 engine is this - first you work on intake and exhaust removing all restrictions so essentially you improve air flow - by replacing stock stock cats with 100 cell or 200 cell ones, replacing stock mufflers to less restrictive ones, fabspeed x-pipe, etc. On intake side it is either OEM CAI with cone filter or simply drop-in oiled air filter from K&N or BMC and also you can install that IPD plenum.

After that OEM ECU programming can push you engine up sacrificing a bit of emissions restrictions stock program has to take maximum advantage of that newly available improved air flow, and only if done in combination with everything else you may get some noticeable difference. As with any modding, it is not one by one bolt-on thing, you got to think it through and do it all based on your goals.

 

I do not have the link but there has been some detailed studies on the effects of different air filters. The looked at KN vs. stock paper, etc. and tested at different pressures and temps. Surprisingly the cheap old paper filter fared quite well!

 

This sounds REALLY good and CANNOT be argued with....HOWEVER....the amount of time that would be spent on the dyno would COST some HUGE dollars,especially IF you do each mod individually on different days!

I am far from having enough money to sit on a dyno for a day or two and even IF I did,I wouldn't,I have been having NO problems with the Gtech and durametric(With help from 1999porsche911,reading/understanding the diagnostics that Durametric reveals).
With the Durametric it shows my O2 sensor readings...at which point I can determine if I am running lean or rich,I also watch the timing...if timing gets pulled,out of ordinary,than I know I need to change something.
Not saying this IS the absolute "end-all beat all",but it is defiantely more reliable than alot of dyno places I have had been,plus I am in control and NOT reliant on someone else.
BOTTOM line is no matter how you get the results before and after tests must be performed under the same conditions.
I am personally NOT looking for bragging rights but rather consistency/safe within'.
I am guessing,BUT I have made probably 50 or so runs with my set-up using the Gtech and Durametric.....IMAGINE what that would cost for dyno time/set-up.........I couldn't imagine!

Stacy

 

Here are some stats I posted from the Gtech book....

https://www.6speedonline.com/forums/2587834-post8.html



Hope this helps!?