BOOST PRESSURE

[Grant]

Interesting!!!
Had a new spec. alternator on my 996TT & asked the OPC to check/re-set the ECU boost pressure at the same time (disconnecting the battery for a few mins re-sets the ECU, don't try this without chatting about it first!), as the adaptive ECU's have an aggravating habit of giving a softer boost over time if you do a daily commute that doesn't stretch the car.
I don't know what they did, but since it has returned the car is simply flying, it is like a different car & now produces 0.9 bar boost (1.9 including atmospheric pressure) at the red line. It is a standard car (with cargraphic sports exhaust) without X-50 & should produce 0.8 bar at around 2700rpm dropping to 0.65 at around 6,000rpm!
The reason for the post is to ask fellow 996TTers (standard & X-50) exactly what boost they are getting, maximum & at the red-line?

 

[jonluik]

The highest boost I have seen on my car was 1.1 bar. However I have 2 KKK 24 Turbo's and 540 bhp, so it sounds like you are doing very well with 0.9 !

 

[Guest]

Although I manage to get a few full throttle moments each day, most of the time it is running at 0 boost (since even at 100mph there is no boost if you are running at constant speed).

Given almost full acceleration, it typically gets about 0.7 bar across the rev range.
I got about 0.9 around 5500 the other day.
I will check on the way home, if I can find enough room to do it.

The highest I have seen is 1bar.

It may have gone a bit soft on me (ooooerr), so if I could get more boost more easily more of the time, it would be better (although it is easy to drive and not slow, even as it is).
It could also be an effect of driving more gently through all the wintery weather, so a few weeks of dry roads should up the performance.

 

[garyw]

Only ever seen 0.8..[]


garyw

 

[Guest]

Sorry, rain stopped play.
Couldn't get above 0.8 without wheelspin on the way home, trying to dodge the other traffic and puddles.
What gear are you trying it in, 2nd or 3rd?

 

[garyw]

eerrr! all of them []

Garyw

 

[Guest]

Redline even in 3rd is naughty, tut tut []

According to the Auto Express driver survey, Porsche 911's were the second highest percentage car stopped by the Police (26%).
(Think this means that 26% of the respondents to the survey who had a 911 had been stopped in the previous 12 months.)

 

[Guest]

I've seen John hit the 1, he hasn't. Too busy watching the road. []

 

[Guest]

The most I ever saw on my X50 was 1.1 bar. Here's a picture of 1 bar at 6,300 rpm in 5th gear...

 

[garyw]

ORIGINAL: Stuart Martin

Redline even in 3rd is naughty, tut tut []

In the UK it is[], Germany perhaps not, I was out playing with some BMW "M" friends, who unfortunately still had the limiters fitted..[]
or
Maybe its because I'm watching the bloomin road so hard I forget to look at the gauge, let alone take a picture, well done Martin!![8D]

garyw

 

[MikeO]

ORIGINAL: Grant


...as the adaptive ECU's have an aggravating habit of giving a softer boost over time if you do a daily commute that doesn't stretch the car.

This sounds a real pain - not being able to immediately get the performance when you want it, relying on the ECU to learn (I suspect to a lessor extent that there's a similar effect in the normally aspirated cars). Wouldn't a better system be to have some sort of "Sports" switch that immediately resets the boost to it's highest level?

I used think it was kinda cool when modified Porsches used to have a knob that you could manually adjust the boost with.

 

[Grant]

ORIGINAL: MikeO

ORIGINAL: Grant
...as the adaptive ECU's have an aggravating habit of giving a softer boost over time if you do a daily commute that doesn't stretch the car.

This sounds a real pain - not being able to immediately get the performance when you want it, relying on the ECU to learn (I suspect to a lessor extent that there's a similar effect in the normally aspirated cars). Wouldn't a better system be to have some sort of "Sports" switch that immediately resets the boost to it's highest level?

I used think it was kinda cool when modified Porsches used to have a knob that you could manually adjust the boost with.

Hi chaps sorry for the delay in replying, not enough hours in the day at the moment!!
Mike I agree with you, it would save a lot of hassle!
Thanks for the reply's, I'm amazed one of you got 1.1 bar, even a GT2 only offers an official 0.95 bar (although obviously with bigger Turbos!). My car is still flying & giving 0.9 bar max near the red-line. I must try & find out what the OPC did!
Cheers
Grant
P.S. Congrats Stuart on your new register role, much deserved it was nice to see mention of the 996TT in Porsche post.

 

[Guest]

I must try & find out what the OPC did

I want to ask for the same thing! Do you think I'll get the same result if I say it feels a bit sluggish?

 

[paulm]

I can only get 0.7-0.8 max in my 53 plate 996TT

 

[sailor]

Yes. Point-eight bar seems to be the standard boost pressure. I have a factory-modded 450bhp engine which still shows 0.8 when you push.

JohnC
993turboX50

 

[996_STEVO]

As Andy mentioned your car has had a remap

 

[michael.mcdonough@fluor.com]

Thanks for all the input, i kind of guessed that it might have had a re-map although i dont have any paperwork to support this.
It's just had a RUF exhaust system fitted which apart from sounding great seems to give it a little bit more power anyway.

Mick

 

[Black80XSA]

make sure you declare the remap and exhaust to your insurer, otherwise you are not covered [&:]

 

[michael.mcdonough@fluor.com]

Thanks again, didn't think about the insurance side of it, and certainly wouldn't have gave a second thought about the exhaust.
Would have been nice of the dealer i bought it from to tell me about the re-map but maybe he didnt know as there is no paperwork.
I had never drove a 996 tt before and part ex'd my factory flat nose which was outrageously fast so i had nothing to judge it against.
Ah well i think i can live with it, getting straight on to the insurance compay.........thanks for all the good advice.

cheers
Mick