Amanda-Jane

why don't you stick a tank of Optimax in then?

AJ

john banks

UK Scoobies on anything based on the standard map seem most susceptible to det from 4400-4800 RPM.

P1s seem to like to det at 3200-3600 RPM coming onto boost and again at 5200-6000 RPM.

Just my impressions - these seem to be weak areas in the standard maps.

You have to retard the ignition timing most in the midrange where there is high boost, high engine load - at higher RPM there is less time for the cylinder pressure to rise before TDC, so you use more ignition timing.

My car is not far off detting anywhere in the range because I have mapped it on the edge. If I put SUL in it has transitional det sporadically anywhere from 3200 to 6400 RPM, but in lots of different conditions it doesn't have a hint of it on optimax.

With the map Kenny has it is quite cautious in all the hot zones, but the ECU can learn advance and retard from the base map.

LG John

Very interesting EvoRSX - I recall you or someone else posting something similar before. I guess my conclusion of SUL with octaine booster is probably the best you can do. I'll see how the car feels over the next few tankfuls and then might consider a bulk buy


AJ, I have a fixed income that doesn't change (local government ) Early estimates suggest that current expendature outweighs income and that I may experience financial difficulty in the near future. The solution seems simple....get rid of whatever puts me under financial strain! That means its the scooby V you...........wonder what I'll choose

markpm

How do you tell if your car is 'detting'?
Can you feel / hear it or what?

Cheers
Mark...

Re-Bitten Hero

(Back to EVO's post for minute )

This backs up what I've found (UK MY00) - running SUL, there is a bit more urgency mid-range, but the power drops off above about 6200rpm or so; running Optimax, it backs off the boost at about 4500rpm, but then holds the power for longer. Rolling road graphs (yes, I know...) back up what I've seen on the road - with Optimax it pulls and pulls to the red line, with SUL it doesn't, but it holds the boost better in the mid-range. Maybe I need half and half

Another 2p worth

Richard

igratton

Er...

MY99 car - are you SURE you have a TD04 turbo ??? I was fairly certain they are all IHI blowers at that age ???

Ian.

LG John

Re: TDO4L... John Banks says so

Mines seems to pull harder at the top end with the SUL than the Optimax. In fact, that is the only place I notice the difference and I've been taking her right up to 7k rpm because it pulls so well up there

Actually it was pulling so well last night in 2nd gear that I couldn't 'feel' the power drop off and ended slamming into the limiter with my foot still mashed to the floor I stroked her gently afterwards to say sorry

tinvek

but won't he crash if he's trying to spot the difeence driving blindfold ?

EvoRSX

John,
Do you find you can generally get more power from running Optimax with advanced timing and lower calorific value than you can running SUL with the timing chopped a bit but with a higher CV?

Andy

Ian2wdsaffcos

I heard that SUL (Esso I think) has a higher MON rating than Optimax so you should have a better top end with SUL but a less urgent mid range than with Optimax (due to Optimax having a higher RON).

Not tried SUL in the Cossie yet but my mates Calibra Turbo DEFINITELY pulled harder at the top end on SUL compared to Optimax.

Cheers,
Ian

john banks

I don't know Andy, would really need to run them back to back on something like an AP22 to find out. Not sure the difference would be large enough to measure with low error? I figured that since I got more advance on the Optimax and it was a turbocharged car I would be making more power (I don't think I have or could reach MBT), but I could be basing that on faulty assumptions. Everything I have been doing on the car in the last few months has been aimed at moving the det threshold, and the power figures from lots of little efforts here and there are steadily improving things. If I had to pull back the timing to cope with lower octane I would feel that instead I should reduce boost.... I have been in the vicious cycle too often of too much boost, too little fuel and too little ignition timing, and the car feels flat and boring. Now I run the boost and the fuelling at a level I think the internals can support for a reasonable length of time and at a level where I still get reasonable timing. Too many variables uncontrolled for me to honestly say I have tuned the car on SUL and compared it to Optimax.

Devil's Refugee

SAxo,

AJ mistakenly believes that your car is the fastest in the area
Obviously you've omitted to tell her about my little beauty around the corner....tut tut

LG John

The little beauty your selling Oh, and there is the whole issue of Andy F's 0-100 'faster than you can blink' beast just down the road too

LG John

Besides, last time we played you were not a problem either The fact you had a hole in your intercooler is neither here nor there

Devil's Refugee

REMATCH!

SiPie

Can I join in ,,,,? er tomorrow preferably

LG John

No problem Theo, hows about in the new year....when you have a 1.8 Focus I'll even take heed of the 'baby on board' notice and maintain a safe distance

Devil's Refugee

Rub it in why don't you <Mutley rant mode>

LG John

I'm sure it'll all be worthwile when the little nipper pops out....well, maybe you'll appreciate it more when all the blood and guts are cleaned up first

Following from that....how is everyone enjoying their lunch

BTW, car still felt pretty rough this morning but it was -2!!!