Gt700 -> Gt800
#16
01-22-2006, 01:32 AM
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Originally Posted by MARKSKIand
I heard that the the high HP cars dont address this issue... I personally seen a gt700 here in chicago at a shop for 2 months cause it had various running problems under WOT... to me it sounds like maf. now, changing it to a boxter maf is really not the answer.... u need a maf that reads past the limit of the stock one... and thus proper ecu calibration to accomodate.... Giac and the tuning community is in CALI.... Im in chicago where air is much denser and its way colder... how is a car going to respond? who has a gt700/750 in cold climate... and how does it really run when its cold. that what i would like to know.
the 986 maf is just a band aid fix.... and I believe that current us tuners have not addressed this issue...
chatter via the grape vine( between tuners.. and the tunning community) is that these high HP cars dont run well in cold climates.... because MAF is not able to handle much denser air under so much boost/ hp....
just my novice .02 cents
the 986 maf is just a band aid fix.... and I believe that current us tuners have not addressed this issue...
chatter via the grape vine( between tuners.. and the tunning community) is that these high HP cars dont run well in cold climates.... because MAF is not able to handle much denser air under so much boost/ hp....
just my novice .02 cents
I have about 5K miles on my turbo since I picked up the vehicle from Todd. I have never had a MAF or a plug problem. The car has seen 90+ degree Vegas weather as well as 30 degree California weather under full boost. I know he used a custom MAF on my car; perhaps he could answer the question....
#17
01-22-2006, 01:46 AM
Originally Posted by RennTechV12
I drove my GT700 tonite at 46f...the only problem I had was the severe wheelhop in 3rd gear. I was doing about 60, downshifted and floored it, the car went to full boost, and the wheels started hopping! The car (like most forced induction cars) loves the cold. I have had absolutely no issues, other than too much power for the tires.
#18
01-22-2006, 02:37 AM
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Originally Posted by RennTechV12
I drove my GT700 tonite at 46f...the only problem I had was the severe wheelhop in 3rd gear. I was doing about 60, downshifted and floored it, the car went to full boost, and the wheels started hopping! The car (like most forced induction cars) loves the cold. I have had absolutely no issues, other than too much power for the tires.
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2001 996TT 3.6L and stock ECU
9.66 seconds @ 147.76 mph 1/4 mile click to view
160 mph @ 9.77 seconds in 1/4 mile click to view
50% OFF ON PORSCHE ECU TUNING BLACK FRIDAY SPECIAL
#19
01-22-2006, 08:28 AM
Originally Posted by VRAlexander
I have about 5K miles on my turbo since I picked up the vehicle from Todd. I have never had a MAF or a plug problem. The car has seen 90+ degree Vegas weather as well as 30 degree California weather under full boost. I know he used a custom MAF on my car; perhaps he could answer the question....
#20
01-22-2006, 09:33 AM
Join Date: Aug 2003
Location: Edmonton, Alberta
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Craig - Thanks for you input. I had the 986 maf installed also. It's been holding up pretty good so far, although I think I may have a coil pack on the way out. I particuliarily like the intake plenum you showed from speed gallery. It looked much more efficient. I'm very interested to hear how the head / cam work goes. I would hope these upgrades would decrease spool time. Any thoughts?
#23
01-22-2006, 02:22 PM
Not just yet, but you are correct the MAP is a better solution in higher HP setups. This what we use in all of our EFI conversions on older cars
#24
01-22-2006, 11:28 PM
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Lots of ways to address the MAF problem depending on how far the limits are being exceeded.
One is to increase the size of the MAF housing. You can bore out the stock housing by approx 5%. You then need to adjust the FP to increase the injector flow by 5%. If you are running 5bar FPR then injector change is required. 60lb injector at 3 bar is = stock at 5.25 bar. Data log the AF ratios at WOT and adjust FP as required. LTFT will take care of drivabilty.
If 5% is not enough the there are you can address the issue two ways. One is talk to Protomotive about a divider circut and recalibrate the signal with this device.
http://www.splitsec.com/products/psc1/PSC1003.htm
Another option is to increase the area of the MAF housing by XX and use the above device to readjust the signal to the ECU.
These problems are not new. Many other marques have seen and addressed the issue.
One is to increase the size of the MAF housing. You can bore out the stock housing by approx 5%. You then need to adjust the FP to increase the injector flow by 5%. If you are running 5bar FPR then injector change is required. 60lb injector at 3 bar is = stock at 5.25 bar. Data log the AF ratios at WOT and adjust FP as required. LTFT will take care of drivabilty.
If 5% is not enough the there are you can address the issue two ways. One is talk to Protomotive about a divider circut and recalibrate the signal with this device.
http://www.splitsec.com/products/psc1/PSC1003.htm
Another option is to increase the area of the MAF housing by XX and use the above device to readjust the signal to the ECU.
These problems are not new. Many other marques have seen and addressed the issue.
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