I have a 2009 997.1 tubro tip... in the summer i took my car to atco raceway with these mods miltek sport exhaust with 100 cell race cats, ipd plenum 74 mm, giac tune, tcu giac software, bmc filters...the cars first run was 11.01 second and third 11.03...it was a hot day with a lot of wind... was very happy with the results... recently i installed the gt2rs intercoolers ipd y pipe and do88 inlet pipes...the car on the street feels much faster... today i went to raceway park and got worse numbers 55 degree cooler weather... the car felt like it didnt want to get off the line.. my 60 ft was really bad the first time was like 2.3 with 12.4 1/4 mile at 124mph... second run was a little better at 11.6 then an 11.8 ..felt like it wasent launching properly..had the car in auto slammed the break rev the car and just wasent moving off the gate....do u think the new mods i did afffected the outcome...

 

i would start with boost leak testing

 

Did you retune it? Sounds like turbo are spooling slower...could be a boost leak, could be the build

 

I would also remove the BMC filter before you need new MAF sensors. They provide 0 benefit.

DC

 

What mph did you run previously? Also that few mods shouldnt result in more then maybe .1-.2 faster but for sure not slower in cooler weather. It's sounds like a boost leak but 124mph trap speeds are pretty good maybe somthing acting up with the Transmission might be slipping out of the hole.

 

2nd that!

 

Not sure, but maybe u need bigger turbos and more gas pressure. The big air intakes are usually installed at the end, after changes to the turbos/hardware. Yours could be to much for stock turbos and stock gasoline pressure.

 

My car is tuned and has BMC filters. No issues with MAF sensors with 80k on the car. No Doubt the car gets more air due to the filters. No oil residue if you take the time to blow off the filters with air in the opposite direction. No sure I agree with your Zero Benefit. Can you please go into more detail why you think there is Zero Benefit.

 

brought car back to mechanic..no boost leak...they tested the car and said it was fine and that i needed to slam the break a little more and rev to a higher rpm to build the boost.... they also said i should consider doing a cobb custom tune with launch control.....does the cobb custom tune have launch control and will i see a great difference than the giac tune i have?

 

No, without changes to the hardware you might experience another loss. If you plan software changes, look for an tcu upgrade.

 

The mph will tell you if you are making more power than before, the ET will let you know how efficiently you are putting the power down. Your free flowing exhaust should let the turbine spin quicker, but the larger intake tract makes more volume to fill on the compressor side. ET's are made in the first 60' but again mph will let you know if you are making any more horsepower.

Sounds like the tune is off down low, possibly needing less timing, and possibly more fuel for your modifications.

 

read codes,if no code then replace plugs...i believe an ic pipe has not locked and leaks...