Super Unleaded petrol and the S2000
12-18-2001, 10:27 AM
#11
Any Super Unleaded is fine. I do get better mpg on Optimax being 98.6+ octane, so I run this whenever I can. For the early miles I ran the car on 97 octane BP Super.
The ECU is happy to adjust to either 97 or 98+ octane. It doesn't happen instantly though. I get most consistent performance when using the same fuel over a period of time. So if you can only get optimax every other fill up, you'll probably only get any price savings - the car won't stay setup to the optimax long enough to get the (small) mpg improvement.
Kagarooing seems to be related to 2 things:
- Dodgy pickup/dying engine. (Doesn't die.). I've had this quite a bit. This seems to be the map sensor. for me a little throttle blip has stopped this.
- Engine pickup/die by itself. I've only had this 3 times and I hate it. The last thing you want in stop go traffic. The only way to stop this has been to dip and reapply the clutch. I've only had this when the car is hot and been sat in traffic. It happened today going past policemen at an RTA. I'd been queuing for >30 mins to get up to the accident site. Set off to go past, and it does it. Thankfully, I had a big enough gap not to hit anything so the only damage was to my pride. I've some parts waiting to be fitted that I'm hoping will cure this. If it ever happens to you, just remember to dip the clutch quick!
-Brian.
The ECU is happy to adjust to either 97 or 98+ octane. It doesn't happen instantly though. I get most consistent performance when using the same fuel over a period of time. So if you can only get optimax every other fill up, you'll probably only get any price savings - the car won't stay setup to the optimax long enough to get the (small) mpg improvement.
Kagarooing seems to be related to 2 things:
- Dodgy pickup/dying engine. (Doesn't die.). I've had this quite a bit. This seems to be the map sensor. for me a little throttle blip has stopped this.
- Engine pickup/die by itself. I've only had this 3 times and I hate it. The last thing you want in stop go traffic. The only way to stop this has been to dip and reapply the clutch. I've only had this when the car is hot and been sat in traffic. It happened today going past policemen at an RTA. I'd been queuing for >30 mins to get up to the accident site. Set off to go past, and it does it. Thankfully, I had a big enough gap not to hit anything so the only damage was to my pride. I've some parts waiting to be fitted that I'm hoping will cure this. If it ever happens to you, just remember to dip the clutch quick!
-Brian.
12-18-2001, 01:07 PM
#12
Originally posted by Cedric Tomkinson
Pete,
I wonder if all those hoods were fully retracted. I sometimes take my finger off the switch a little early!
Pete,
I wonder if all those hoods were fully retracted. I sometimes take my finger off the switch a little early!
12-18-2001, 01:11 PM
#13
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I switched to Optimax, not noticed any performance difference but its cheaper
As for kangooroooooingg, happend on SUL, happens on Optimax, as Brian says, when the car gets hot, even in current temps if I am sitting in traffic, crawling my way into or out of London, I occasionally get the jump factor, and the only solution is dipping that clutch or if I am rolling, then pulling away in 2nd. I don't remember it ever happening in 2nd
, perhaps its just coz I give it more gas. In 1st I generally pull away with 1200 ish rpm, so its down near the line anyway.
Have tapped the Map sensor, but not yet reset the ECU, been running exclusively on Optimax for a couple of months now though
As for kangooroooooingg, happend on SUL, happens on Optimax, as Brian says, when the car gets hot, even in current temps if I am sitting in traffic, crawling my way into or out of London, I occasionally get the jump factor, and the only solution is dipping that clutch or if I am rolling, then pulling away in 2nd. I don't remember it ever happening in 2nd
, perhaps its just coz I give it more gas. In 1st I generally pull away with 1200 ish rpm, so its down near the line anyway.Have tapped the Map sensor, but not yet reset the ECU, been running exclusively on Optimax for a couple of months now though
12-18-2001, 01:58 PM
#14
I've been reading Dave Walker's engine management book (he's CCC's tech guru). This has given me a theory as to why the kangrooing happens.
The ECU has a seperate 'idle' map that is used for low rpms. It's designed to maintain a constant target rpm based off a few factors. There are also correction maps for coolant and air intake temperature.
My guess is that the ECU is getting hysterisis going between normal and idle maps in certain conditions, due to rare interaction between the correction maps.
It's only a theory based off generic ECU information, but it's plausible I think. Makes me hopeful that with improvements to air intake or coolant temperatures the problem can be avoided.
-Brian.
The ECU has a seperate 'idle' map that is used for low rpms. It's designed to maintain a constant target rpm based off a few factors. There are also correction maps for coolant and air intake temperature.
My guess is that the ECU is getting hysterisis going between normal and idle maps in certain conditions, due to rare interaction between the correction maps.
It's only a theory based off generic ECU information, but it's plausible I think. Makes me hopeful that with improvements to air intake or coolant temperatures the problem can be avoided.
-Brian.
12-18-2001, 02:15 PM
#15
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I am wondering if your fuel ratings are similar to those in the U.S.A.
I have been using 87 Octane (not sure what that translates to outside of this country?). My dealer said that any octane will do...
I have been using 87 Octane (not sure what that translates to outside of this country?). My dealer said that any octane will do...
12-18-2001, 02:34 PM
#16
[QUOTE]Originally posted by LBRunner
[B]I am wondering if your fuel ratings are similar to those in the U.S.A.
I have been using 87 Octane (not sure what that translates to outside of this country?).
[B]I am wondering if your fuel ratings are similar to those in the U.S.A.
I have been using 87 Octane (not sure what that translates to outside of this country?).
(We get the big 98 RON minimum one 
)
12-19-2001, 06:34 AM
#19
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Originally posted by Dog Biscuit
Also, I am sure I read somewhere that the 2002 can be run on 95RON long term without any problems.
Also, I am sure I read somewhere that the 2002 can be run on 95RON long term without any problems.
It does qualify the use of 95 Ron by saying 'If 98 Ron is not available', implying it's not really desirable!
