john banks

On Delta Dash you can see the knock correction happening, and it apparently is quicker to do so than you can see on a Knocklink.

My question is - does EGT monitoring add any useful information to this? If the EGTs are high the in-cylinder temperatures will be high. This will adversely affect the knock point and the ignition will retard. Then the EGTs could rise still further.

If you have the timing advanced without much/any retard you are presumably at the point for lowest EGTs at that load, boost, fuelling?

What if any situations would you get high, possibly hazardous EGTs, but no knock retard or does the knock retard really tell you what you need to know?

And whilst I have your attention, how is 7% CO too lean for EGTs on a UK engine with a new turbo, assuming the intake temperatures are sensible? At 7% CO do you have to retard the timing a lot more than at 9% CO?

The Link manual suggests 7% CO, but the Link cars I have seen are running over 9% CO.

john banks

Anyone?

Cosie Convert

Probably cos u asked 6 questions at once !!! I've forgot half them already

You probably know my views already but you did say "anyone" So I'll add my 2c

I have my reservations about relying on the std knock sensor/retard function. It is a fact that as you increase the power output, the engine noise increases. The knock circuit does not know that you have fitted a Dawes etc.
It is possible, even probable, that the knock detection circuit is triggering retard as a result of increased power 'noise' in which case you have a very effective automatic power limiter

FWIW - On Jims rollers today my CO was logged at 8.0 and my EGT max was 620 deg C. On the open road with cooler air I have approx 100 deg more EGT and a few % less CO. So in my case air density would appear to be a major factor in EGT.

I also know that a high exhaust backpressure raises EGT, regardless of timing or mixture.

If you fit a larger compressor (I'm guessing here ) it would be worthwhile monitoring EGT before and after fitting as this will be a good indicator of the new turbo's efficiency.

john banks

You put me onto this EGT thing in the first place and have me reading about taps and drill bits and devilling around about all the hot oily bits - not my natural habitat - the ECU I prefer

Will get to it then, just procrastinating as I prefer laptops to drills and tapered taps - will have to go and buy a boiler suit Why did I get gravel put on my drive

Now, how many PSI am I chasing at at 6000 RPM Still I won't get 350 BHP though.

Andy YHM

[Edited by john banks - 4/28/2002 11:28:04 PM]