Mash

has anyone quantified the actual power increase delivered by fitting a Dawes - eg before and after dyno run, 0-60 & 50-70 timings etc ?

Having briefly fitted one to my MY01 - tweaked right up to the fuel cut limit - I honestly could not notice a big difference....perhaps I was expecting greater things...

john banks

There were some dyno figures showing about +10% I think.

On my car (approx figures from memory) 50-70 in 5th unmodded 8 seconds, PPP 7 seconds, PPP and Downpipe 6 seconds, + Dawes 5 seconds. Other increments were improved by less, but still about 10% depending on what you start with. It is more the throttle response and wide torque band, but on the MY01 it has a nasty habit of not responding to simple mods like earlier models - it pulls timing and overfuels in some tests, others seem to get good results- Scoobysport exhaust (full system) tested on MY01 does very well, but Autospeed showed basically no improvement unless you change the ECU with a similar setup. Puzzling.

ScoobyJawa

Scott W got about 13bhp and about 20-30lb/ft more IIRC. UK MY00 full decat and induction.

Jay m A

iTrader: (2)

Matt

It may not be underreading as much as you think!

On the dyno at PE on my car the select monitor said 13.8 PSI, my boost gauge showing around 0.95 kg/cm2. On the road however it held 1.0 or slightly more on the way there, and on the way home.

Something to do with the loading effect I believe Anyway the way I see it is that even if the rolling road is 'generous' with their figures its probably close to 'on road' BHP

cheers

Justin

Mash

thanks to all of you for your input, I shall have another go at fitting the Dawes and the AFR and persevere with it a bit longer. I need a more accurate turbo gauge first - more expense!

john banks

Try running at only 15.5 PSI. Then the temps will be cooler, you will still have similar power at the top, but less change of overfuelling and ignition retard like the MY01 seems prone to at higher boost. This at least on US cars was the cause for loss of performance over time. I also hope you are running a 1.5mm bleed hole, Cosie Convert doesn't get knock and gains power apparently until 3.5%CO , but he runs water and methanol injection. I saw 5% CO at part throttle/15PSI with the original bleed hole on the Dawes and this makes me unhappy. I want 7% CO or higher over 15PSI. Call me a wuss, but my engine stays cool.

Cosie Convert

Your a Wuss

I didn't say I gained power down to 3.5%co I said I didn't get increaseing EGTs till then. (I run 5.0% > 5.5% )

I wish I was still working for Shell. The profits must be booming all that fuel you're pouring in

john banks

OK

But I am not capable of rebuilding my engine in my shed like you are

mutant_matt

CC,

You're not seriously running 5.5%CO on WOT, full boost and high revs are you? In a Scoob?????

Matt

john banks

"Are you sure that 5% CO is too low ? I've been doing a bit experimenting lately and have found more power by going even weaker than this. (don't try this at home)"

CC was quite rightly just taking apart my assumptions (presumptions) not based on data when I said 5% CO was too lean at part throttle with a Dawes with no extra bleed hole in this thread http://www.scoobynet.co.uk/bbs/threa...D=78293&Page=1

But please note he also logs a lot: (and has a Knocklink and WI)

"I tune for maximum acceleration 'G' force, which I data log. I also monitor charge temp, EGT, boost pressure and exhaust back pressure."

If you can control knock and temps at 5-5.5% CO this is theoretically where you will get most power. Andy's car does haul *** to put it mildy and he is running more power now. He will I am sure be getting nearer to 12 rather than nearer to 13 second quarters soon

Cosie Convert

Yes Matt, CO 5.0% and at 23 psi boost and on a 95 import
This was not a target I set, merely the resulting CO I ended up with after some 'conventional tuning'

1/4 mile = 12.56 @ 115 mph 0 - 100mph 9.9 secs.(speedo 109mph)

Does this sound ok from a std ECU, Turbo, intercooler and puny 380cc Grey injectors ?

Here is an old power trace before my latest mods, running 19 psi (don't want to give away new secrets!) The drag strips timing kit printout was within 1 mph and 0.2 seconds of this

Oh yes, power is at the wheels !!!



Andy



[Edited by Cosie Convert - 3/13/2002 2:00:30 AM]

mutant_matt

Matt

mutant_matt

Using the Dawes I have raised my (held) Boost from about 0.95 to 1.125 (approx as read off the Defi gauge) and the power has gone from 229bhp to 244 and the torque from 221 to 247. Both of these results are from PE's rollers on similar (bloody cold ) days. Having said that, the Defi actually reads kg/cm3 or something similar and also over reads so I am actually holding a tad over 1 "real" bar (as reported by the MAP sensor).

I may turn the boost up to hold a real 1.1bar once I'm happy with the part throttle fueling at the current level. The current WOT fueling is about 10.5-11% CO which is still really rich (and safe).

More important IMHO than the increase is the improved spool up, higher peak torque earlier in the rev range and the fueling is also slighty improved (I presume by running a fraction leaner). The torque curve is also higher for longer and tails off less at the top end.

All of this makes for a much more drivable car which is much more urgent and more flexible in higher gears. The only power mods are the Dawes and a PPP BB so there should be plenty more to come with a decent DP and mid section...

Matt

[Edited to mention it's an MY00]

[Edited by mutant_matt - 3/12/2002 8:48:36 AM]