I found my chipped 997.1 to be much more sluggish at low rpm and have much more lag than my earlier chipped 996.This surprised me-I thought there might have been something wrong,thinking the new variable geometry turbos should be better.But my tuner said it was normal-the 997 having a lower CR,for one thing.Maybe your car is normal for a 997....

 

Who is your tuner?

 

My tuner-DMS Automotive of the UK.

 

Interesting.

petey01 If you've really got the lind of lag you are talking about thats unacceptable. You really should complain to them or have them put it back to the stock tune.

I have a Protomotive tune and my car goes like its been shot out of a gun....zero lag . Something must be seriously wrong somewhere with your tune.

DMS have an agent out here and ask some brain damage figure of 5.500.00 Aussie for it and the same agent also sells the APR for 4200. Aus. Im so thankfull these tunes were so OTT pricewise when i did my shop around because if they were priced in line with all the US tunes i would have stitched myself up by getting one....phew!!

 

My stock 997 seemed very sluggish below 2500 rpm,compared with my chipped 996.When it was tuned,it only helped a little below 2500rpm,(lots of gains above that)leaving it stil,below the level of my chipped 996 for bottom end response.Auto car magazine,in their road test of the 997,did pass comment on this-comparing the off boost response of the 997 unfavourably with that of the 996.I am pleased with my chipped 997,overall-if I wanted to reduce turbo lag and pick up a bit more torque everywhere,an aftermarket exhaust with less backpressure,would be a good modification,allowing those turbos to spool up faster and at lower engine rpms.I did read a rumour,somewhere,that said that the earlier 997s had a different turbo spec to the later ones,like mine,which meant that the earlier cars were more responsive.But I don't know if there is any truth to that rumour at all.

 

I also noticed some lag on my 6speed TT. Perhaps I should downshifted but I definitely noticed some lag if RPM is low.

 

Lag and boost threshold are two different characteristics. What you are describing at low RPMs sound more like an inherent characteristic of VTG's boost threshold.

If you want to measure lag, you need to be at an RPM above the threshold, then accelerate to WOT. I am willing to bet that a proper tune to a VTG has minimal lag compared to other setups.

 

BBYWU,yes,you're right-well done for pointing that out.I believe we mean that the throttle response is poor at low rpm when the engine is off boost,or just starting to boost.My chipped 996 started boosting at lower rpm than my chipped 997.Once I am above 2750rpm,response is always excellent.On the road,the biggest difference would be noticed when pulling out into the outside lane at 50mph and accelerating in 6th.Now the acceleration is weak and I need to be in 4th or 5th-in my chipped 996,6th would be fine.

 

Are you still using the stock exhaust or have you changed it out? I recall when i had the stock exhaust there was some lag....not much tho. The car did feel a bit choked at times. I'd really only get to feel the lag from idle in second gear after giving it immediate wot. Then you would feel a bit of lag but not something that could be called a huge amount. One of the main purposes of the vtgs is to eliminate lag at the lower rpms whereas regular turbochargers rely totally upon impeller shaft speed generated by the increase in exhaust gas flows as the engine dials up revs. Have you considered the possibility that your tiptronic gearbox is slipping?

 

My car is flashed and I have stock exhaust...The turbos kick in about 2500-3000rpm before you feel the boost...I need to upgrade my exhaust, but haven't choosen one yet...

 

Same here,mine is flashed but stock exhaust.I am considering the cargraphic one.It comes in 3 sound levels (I would choose the quiet one) and is lighter and they claim nearly 50% less backpressure.On the other hand,I might wait and get a GT2 next year.I need to drive one first and decide.The GT2,by the way,is reported to have far better thottle response than a regular 997 turbo,due,at least in part,to a better flowing exhaust.Read the excellent review on the GT2 on "pistonheads.com" ....

 

I wouldnt waste my time with anything else other than an EP1 Europipe. Stick that on and it will go some way removing that lag amongst giving other good things. Take it to the bank. If you are used to the stock system you'll get rude shock when you put anything else on particularly on a tip that has atendency to hang around in the drone zone. Be carefull of the claims .

 

Big ++ on the Europipe, but I like EPII. Love that masculine noise.

 

This is pretty much standard for a stock car, in my experience. When you hit the gas there's a second or so where you think, "Is this thing on?" which is followed 1-2 second later by "Crap...yes it definitely is!" as you get pinned to the seat. VTG turbos or not, the car has lag. Supposedly improved with the new engine although I imagine it will always be there to some degree...definitely better than my dad's old 1977 930 turbo though!

 

just floor the throttle and hang on....lag my ****