Activa at the Pod...

XantiaMan · Unread post by **XantiaMan** » 26 Oct 2008, 21:24

Well what an eventful day! It started with heavy rain on the way to santa pod, after a quick stop at a services it decided to throw a fault code at me. Fortunatly we were not far away from jim's and he very kindly reset my ecu, a strange fault come up with a open circuit boost control valve. Its not come up again since its been remounted.

The rain did stop and after a 2 hour wait to dry the track we were off. A dreadul first run with no grip at all, a 2.9 60ft, 17.2 @ 81 mph. The other downside was now the ecu had been reset it now had to relearn all its parameters.

On the 2nd run I did a granny launch and got a 2.6 60 ft, 16.8 @ 82 mph. A bit more revs on the 3rd launch and we were down to a 16.6 @ 82 again with a 2.46 60 ft.

The final run because we were running out of light gave a 16.3 @ 84 mph, and a 2.42 60 ft. This improvement was interesting as the launch was pretty much identical to the previous run but 3 tenths of a second quicker and 2 mph on the terminal.
Another run and i'm sure it would have seen a 15.9. As the ecu adapted the car got quicker and on the run home, it was faster than it had been all day!

Still, next time we at least have a benchmark figure. My tyres were on their last legs so the improvment in launch will improve the time a lot. Bar a whiff of extra boost the car is standard, with a few choices mods like a decat, performance filter and feed and boost a bit higher it will be a mid 15 second car, quick enough to get moving. Its gearing is not set up for acceleration so it did well, for example Astra Gsi turbo's did a 15.9 on the day. The rain made the track very slippery even when dried and glued, and a brisk headwind also did the terminal speed no favours., but overall I was happy with it on the day, it certainly raised a few eyebrows!

Gareth

XantiaMan · Unread post by **XantiaMan** » 27 Oct 2008, 06:13

Unread post by **CitroJim** » 27 Oct 2008, 07:50

Nice one Gareth

I can well imagine a Xantia sitting on the 'strip raised a few eyebrows

The spelling is terrible on the advertising hoarding. Don't they know there is a "Y" in the word used to describe those round, black rubber things that go on wheels!

Exhume.dk · Unread post by **Exhume.dk** » 27 Oct 2008, 20:45

Nice, that turbo Xantia runs pretty well indeed

The Activa turbo must be at least in the high 13xx Kg. range or something like that

Did a 15.05 time in a "trackday-stripped" 890 kg Pug 309 16V with diff.lock,on semi slick a looong time ago.

Found this video of a Xantia vs. BMW 745 ( maybee im the only one that havent seen it yet)

Exhume.dk · Unread post by **Exhume.dk** » 27 Oct 2008, 20:47

-came up twice-edit

XantiaMan · Unread post by **XantiaMan** » 27 Oct 2008, 21:22

Exhume.dk wrote:Nice, that turbo Xantia runs pretty well indeed
The Activa turbo must be at least in the high 13xx Kg. range or something like that

Did a 15.05 time in a "trackday-stripped" 890 kg Pug 309 16V with diff.lock,on semi slick a looong time ago.

Found this video of a Xantia vs. BMW 745 ( maybee im the only one that havent seen it yet)

Activa weighs 1430kg, with me in it, we over the 1.5 ton mark

Looking forward to next year, its a mid-15 second car easily and thats quick enough to keep me satisfyed. I hope to make a decat soon as i reckon that will make quite a difference.

XantiaMan · Unread post by **XantiaMan** » 28 Oct 2008, 18:01

I've just done a quick calculation of 0-60 based on the 1/8th time and it comes up as 8.4 seconds, a good second quicker than standard which is pleasing especially when there is more to be had in its current form.

Exhume.dk · Unread post by **Exhume.dk** » 28 Oct 2008, 18:04

XantiaMan583 wrote: Activa weighs 1430kg, with me in it, we over the 1.5 ton mark

Looking forward to next year, its a mid-15 second car easily and thats quick enough to keep me satisfyed. I hope to make a decat soon as i reckon that will make quite a difference.

Yes, know what you mean..and 15-sec. is a "fair" time..especially used in a streetcar, or something for a daily use( or misuse

)

Turbochargede engines is always happy for a more free flow in the header/downpipe and more so when the boost is increased and less backpressure, and heat build up in the turbine and manifold.
But there is allways a limit, a 5" would'nt give anything, other than a slower spool up..3" is the sweetspot on that type of application, so i've been told

Oh--well, ranting again

XantiaMan · Unread post by **XantiaMan** » 28 Oct 2008, 18:22

I'm going for 2.5 inch which is good for over 300bhp something it will never have, its still a family car and I don't want to compromise with excess noise and boom. I do feel the standard exhaust note is very plain and a bigger bore will make it a bit deeper in tone, with 2 boxes it will still be quiet enough...

addo · Unread post by **addo** » 28 Oct 2008, 19:52

Any restriction on a turbo exhaust (either pre or post impeller) is wasting power.

There may be an optimum size based purely on gas velocity calculations but they will probably assume steady-state operation; not applicable in real world driving.

You could look for dyno results on similar size, similar RPM motors with single turbos, but the amount of internet "waffle" you'll need to sift through may induce a psychopathic killing spree.

The big issue with a 2½" bore is that bends may induce restriction unless they're all butt-welded mandrel pieces. Going up to 3" will just add extra capacity for any points where it may otherwise choke; sort of raising the lowest common denominator.

Regards, Adam.

XantiaMan · Unread post by **XantiaMan** » 28 Oct 2008, 20:07

I agree, but even with the bore restricted at bends down to 2.25 if that were the case, there is still enough benefits to running a bigger bore than standard. My maestro runs a 2.5 and never had any probs, and that pumps out a good deal more than an activa. I certainly wouldn't bother unless I had extensive mods and was looking for that last 5 bhp. Gareth

XantiaMan · Unread post by **XantiaMan** » 08 Nov 2008, 10:38

Found some figures for the higher performing Xantia's...

1/4 mile for V6 Auto (Exclusive) 16.9
1/4 mile for Xantia Activa V6 Manual 15.9
1/4 mile for Xantia Activa CT 17.2

All standard times of course.

So whilst its obvious that the V6 has more grunt, coupled to a slush box really blunts the acceleration although it will feel quite swift. Not sure of the gearing for the V6 Activa but i suspect its set up a bit better than the CT box which has quite a long 1st and short 2nd.