A question of power
Joined: May 2001
Posts: 3,332
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From: On a fencepost
Originally posted by fluffyninja
When was the ECU update and did it correspond with the Squirt Jet Recall?
Spoke top a few people at work about that recall and we reckon that they were having problems with piston cracks and wanted additional cooling of the pistons and the spark plug change could also affect this.
Maybe ECU change was somehow related? If there is a degree of knock this could be hurting the pistons and like some people on here there's going to be a few people who can't/won't use 98ROn
When was the ECU update and did it correspond with the Squirt Jet Recall?
Spoke top a few people at work about that recall and we reckon that they were having problems with piston cracks and wanted additional cooling of the pistons and the spark plug change could also affect this.
Maybe ECU change was somehow related? If there is a degree of knock this could be hurting the pistons and like some people on here there's going to be a few people who can't/won't use 98ROn
The spark plugs were recalled because of a washer problem - there were several cases of spark plugs working loose, with nasty consequences.
The ECU change, I think was more an update to get a little more performance. The original mapping was propably more conservative than it needed to be, and Honda have tweaked things a little now they've the data from a lot of cars doing a lot of miles.
San2000:
Who?
Knock, isn't a vibration frequency. Quite description of the 3 things you'll have heard:
Pinking:
Light metallic sound caused by the ignition timing being too advanced. Caused by pressure rising in the cylinder too quickly, which makes the piston rattle against the bore as it goes over TDC (top dead centre - top of the stroke.).
Knock:
Normally, the spark plug ignites the air/fuel mixture in the cylinder, which then burns away from the spark plug in a flame front. The air/fuel mixture furthest from the spark plug burns last - this bit is normally called end gases. Under some circumstances, the end gases auto-ignite. So instead of one flame front, you've now got two. The sound these make when they collide, is the 'knock'. (If you read back on the explaination on higher octane being harder to ignite, you'll see now why it's less likely to knock - less change of it auto-igniting.)
Pre-igntion (or detonation if you prefer):
This is when the air/fuel mixture ignites on something hot in the combustion chamber (usually the spark plug) before the spark. Pre-ignition quickly destroys pistons, rings, valves, spark plugs - a very quick way to destroy an engine.
-Brian.
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Joined: Mar 2003
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From: SE VTecville
[QUOTE]Originally posted by fluffyninja
[B]To try and improve the power of the engine the ECU will begin to advance the ignition timing until the knock sensor "hears" (it is listening for a specific vibration frequency in the engine) the engine knocking and that knocking crosses a threshold limit. At this point the ECU retards the timing again and the two maps then begin to argue where the ignition timing should be.
[B]To try and improve the power of the engine the ECU will begin to advance the ignition timing until the knock sensor "hears" (it is listening for a specific vibration frequency in the engine) the engine knocking and that knocking crosses a threshold limit. At this point the ECU retards the timing again and the two maps then begin to argue where the ignition timing should be.
Registered User
Joined: Apr 2003
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From: Chester
It's kind of difficult to explain without an engine to demonstrate on. Brians definitions are very good to go by.
If your engine sounds like a diesel just starting up that might be an indicator too
If it's not a constant problem you may also notice a power loss and the car bogging down under certain conditions (i.e. high load low speed for example)
Brian, question for you. What do you do to get so much time on S engine testing?
If your engine sounds like a diesel just starting up that might be an indicator too
If it's not a constant problem you may also notice a power loss and the car bogging down under certain conditions (i.e. high load low speed for example)
Brian, question for you. What do you do to get so much time on S engine testing?
Joined: May 2001
Posts: 3,332
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From: On a fencepost
San, quite a few Honda's I've been in have pinked a little. Generally not anything to worry about. I've not heard an S2000 pink though. I wouldn't worry about the others - chances are, you'll get a CEL if there's any chance of a problem, and the ECU will switch to running a very conservative map. (I've had this once.).
The reason I've spent so much time learning (and testing) the F20C is simple. I wanted mroe power (safely) from my engine to make life easier. (I've problems with me left knee, so more power, or rather low down torque means less gearchanges and more chance to be lazy when resting the knee.). Since there wasn't much experience with the S2000 in the UK, the only way to find out for sure, was to do the work myself. Things are gradually changing, but it's not like having a Rover K series where you'd go to DVA.
So does anyone have any good knock jokes then?
-Brian.
The reason I've spent so much time learning (and testing) the F20C is simple. I wanted mroe power (safely) from my engine to make life easier. (I've problems with me left knee, so more power, or rather low down torque means less gearchanges and more chance to be lazy when resting the knee.). Since there wasn't much experience with the S2000 in the UK, the only way to find out for sure, was to do the work myself. Things are gradually changing, but it's not like having a Rover K series where you'd go to DVA.
So does anyone have any good knock jokes then?
-Brian.
Registered User
Joined: Mar 2003
Posts: 19,285
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From: SE VTecville
Brian,
I've heard you mention probs with your knee before. How come you've gone to all this trouble investigating the F20C and the S2000 when you could have got another car with more torque?
(if you dont mind me asking)
I've heard you mention probs with your knee before. How come you've gone to all this trouble investigating the F20C and the S2000 when you could have got another car with more torque?
(if you dont mind me asking)
Joined: May 2001
Posts: 3,332
Likes: 2
From: On a fencepost
Originally posted by san2000
Brian,
I've heard you mention probs with your knee before. How come you've gone to all this trouble investigating the F20C and the S2000 when you could have got another car with more torque?
(if you dont mind me asking)
Brian,
I've heard you mention probs with your knee before. How come you've gone to all this trouble investigating the F20C and the S2000 when you could have got another car with more torque?
(if you dont mind me asking)
The S is the best all round 'compromise' sports car from a (long...) list I test drove.
Besides, the trouble with the knee worsened after getting the S. So I decided rather than giving up, I'd spend some time and effort seeing if I could improve the S. It is getting to the stage where I'm considering other options, but the S is staying for now at least.
-Brian.