Lambo

Hi everyone, just fitted my Dawes on my MY99, de-cat DP and ITG.
and there is a noticable difference in mid range urge.

Some boost figures

pre-dawes dawes fitted
RPM Boost Boost
2000 6 not sure, not much
2500 13 14
3000 14 15
3500 14 15
4000 14 15
4500 13.5 14.5
5000 13.5 14
5500 13 13.5
6000 11 not sure, was tailing off
6500 9.5 not sure

Pre Dawes the boost spiked at 15 before settling back, now it peaks at 16 psi

My question is, should I be happy with this or is it always necessary to alter the Dawes settings. Are the factory settings done accurately or just set thereabouts ?

One other observation, I've got the Dawes AFR fitted as well, and under full throttle its always in the blue i.e. very rich. I have earthed it to the cigar lighter and noticed that using the side or headlights will effect the AFR readings, gives a lower one. Looks like I'll have to earth it direct to the battery.

Cheers
Lambo

HarryBoy

Sounds fine. Seems you have been cautious with the setting, a good idea, you may get another .5/1 PSI out of it but how does it feel at the moment? Have you opened up the bleed hole?

Harry

Lambo

Harry, it came with a 1.5mm bleed hole. The car feels good but seems to want to give more.
The reason I'm questioning the boost values is that John Banks was getting ;

2000 - 10
2500 - 18
3000 - 18
3500 - 18
4000 - 18
4500 - 18
5000 - 17
5500 - 16
6000 - 15
6500 - 13

I know he has a PPP but these figures are a lot higher than I'm getting... I want more power !!

Lambo

john banks

My car does seem to hit hard below 2500 RPM for some reason. I tightened the actuator to get the boost to hold better 4000-5500 it was floppy before and boost was already dropping - now still at 16 PSI at 5500 RPM - previously it was about 14 PSI.

I think on the standard ECU subject to no fuel cuts and your gauge being accurate you could happily hold 16 PSI which will feel perkier.

The only reason to keep fiddling is if you find yourself always running next to fuel cut, which is fun and then not fun. I have been amazed how consistent and spike free the Dawes boost is - I have not seen more than 0.5 PSI variation over a 25 degree range of temperatures.

The PPP has a 19.3PSI fuel cut so allows you to run rather more boost.

[Edited by john banks - 3/19/2002 10:59:20 AM]

HarryBoy

Lambo, just to make you feel better I am also envious of JB's performance figures

I get nowhere near to his, I have a MY00 with SS DP. Mine are similar to yours but I have the dawes wound up a little more.

Harry

Lambo

Right, I've now tweeked my Dawes ( one whole turn tighter ) and just been out with a co-pilot to write down the boost levels

----pre-dawes - dawes std - dawes tweeked
RPM - Boost ------ Boost ----- Boost
2000 -- 6 --------not sure --- no reading
2500 -- 13 -------- 14 -------- 12
3000 -- 14 -------- 15 -------- 16
3500 -- 14 -------- 15 -------- 16
4000 -- 14 -------- 15 -------- 16
4500 -- 13.5 ------ 14.5 ------ 15.5
5000 -- 13.5 ------ 14 -------- 15
5500 -- 13 -------- 13.5 ------ 14.5
6000 -- 11 ------no reading --- 13.5
6500 -- 9.5 -----no reading --- going too fast

The AFR meter was on a blue light the whole time ( now rewired to the battery negative )

Boost is slighly higer in 5th, probably 16.5 and peeks at 17.5, no sign of any fuel cut out.

The car is really flying, it seems so eager in 4th and 5th gears.

Only problem now is that I need to get more petrol as it seems to be running out rather quickly...

nom

I like the 'going to fast' reading

[can you believe I spelled something wrong with only 7 words?? ]

[Edited by nom - 3/21/2002 12:00:28 PM]

Lambo

I now have a value for 'too fast'

6500 rpm = 12 psi of boost.


Quick question though, once I'm happy that the car is fueling enough can I safely remove my AFR meter or does it need constant monitoring. Only reason I ask is that its currently blue tacked to the ash tray and it looks a tiny bit unsightly !

[Edited by Lambo - 3/21/2002 1:30:30 PM]