nitro

I'm sure you could do better than that, Nitro - Admin


EDIT - Admin

__________________
When only the BEST will do!!

Mycroft

Nitro apologises - Admin

A very emotional, but in the end useless post, I have stated twice before in this thread that if you are happy buying any OB you presently use then continue to do so.

Peter
I think you will find as already stated here that 6 ron relates to POINTS which is exactly as I have found!

What difference have you found in your best times at quarter days? Do they not vary at all!!, mine do and so does everyone elses, 0.8 of a second difference is quite common when runs are on the same day, let alone a few days apart!

EDIT - Admin

Hugh Keir

Agree with most things in your last but one post, but It is simply a pressure spike at around 6400hz. The sensor is tuned to this frequency and this frequency only. seems inconsistent with other stuff I have read

I have a spec sheet from Bosch which describes the function, installation and use of their range of 3 knock sensors. It says that they monitor frequencies in the range 1 to 20 kHz and talks about the sensors linearity between 5 and 15 kHz which is fairly steady.

Looking at the signal evaluation module that Bosch sell to interface with the above sensor, it is capable of analysing for 9 test frequencies between 5 and 16 kHz which presumably allows the individual car manufacturer to focus in on the frequency of most interest.

I have also read somewhere that the frequency produced by detonation is loosely connected to the bore of the engine.

Mycroft

There is no inconsistency between what I posted and the Bosch info, the sensor needs to be a good quality listening device and the linearity does the unit credit, but being able to hear all the different frequencies is essential so as to provide a 'white noise' against which the 'ping' is heard. Think of it this way, if it only sends a signal back to the ECU when it hears anything, at 6400hz then it would pickup the occasional harmonic from the valves etc, it would be difficult to distiguish if this 'other' noise was really a 'ping' so the unit sends a continuous signal from all over the frequency range the ECU is programmed to use this, then when the 'ping' arrives it can distinguish it for what it is.

the ECU requires a comparator.

Peter

Mycroft,

Have to admit that I've never done a 1/4 time, much prefer using the car for what it was designed for, circuit driving. So, and I'm not trying to trip you up here, despite you posting

"I pulled a 12.2 quarter using that mix, it make the car very brutal at the top end as it is here that the toluene really punches its full weight."

and

"Without Toluene I can just break under the 13's (12.984). "

you are not actually putting this down to the additional power toluene can give, more just inconsistency in your driving, my mistake.

Why do you refuse to answer how you tested octane levels? It's been asked of you some 3 or 4 times now.

Mycroft

Only with Toluene, can my car catch a 12.2!

I thought I had answered this but re-reading the thread I realise that I haven't.

The devices we used were Bumah Octet (old and slow but a very good final check and we have an array of simple di-electrics the latest one and the most accurate is the Kavlico it is now issued to the HM C+E to replace the vans they used to use, they do the test with the hand-held, the results are to 2 decimal places. which is about one eighth of a RON point. They have a website, we bought ours from there.

We used to use the Petroleum Research handheld but that was fiddly and not too accurate and could be 'fooled' by Iso-parafins! so there may be a clue in there!

The latest devices cost under a £1000 and work fantastically well and are used now by the FIA at all F1 events.

phatty

Sorry to go of track, but I'd just like to ask Nitro a question.

Does 5:06PM UK time = Pub kicking out time in Oz by any chance?

nitro

2hundyman Well it depends on what day of the week.
on the weekends yep pretty close during the week around 3.00pm your time

__________________
When only the BEST will do!!

Syed Shah

Mycroft, (no doubt you will remember me from the Supra BBS):

Now, there is one thing I do not get: That is, why would these companies that produce octane boosters bother changing "flame fronts" and "fooling" knock sensors? Surely doing this would require a lot of work and research, as it in itself sounds very complex, why would they not just produce something that boost the actual octane (much simpler to do)?

__________________
Supra MKIV x 2
R6 *rip*
Soarer TT

Peter

Mycroft,

One other point too, you mentioned that the stock knock sensors fitted to the GT-R (amongst others) were next to useless. Would it surprise you to know that well established and respected tuners in this country rely upon the stock knock sensor to determine whether the car is detting or how near the car is to detting whilst mapping the car?

I would certainly be interested in fitting one the digital knock sensors you had found if that were possible. It would be very interesting to compare this with the stock sensor.

Peter.

nitro

SYED SHAH
You are not welcome on this site!!! you are by far to intellegent and say things so simple. Mind you there are a few others on here as well that know whats happining.!!!

This form of communication is not understood in this forum - please employ a dialect more in tune with the rest of the members - Admin

Thats EXACTLY WHAT WE WANT TO DO IS TO SHOW ON THAT THING THAT WE HAVN'T INCREASED THE OCTANE.!!!!! CLEVER??

If you do a PROPER test and the WORLD std test and it would have to be pretty dam obvious, well at least i thought it would be, but after reading the crap your putting on here you DONT!!!!!!!
The only octane test that counts or is the proven way is the ASTM D2699 test and if you dont know what that is then its the test carried out by the only engine which can do it.
A KNOCK ENGINE !!!!!! and ive even included a pic of it for your small eyes to see.
YOU see it has a moveable crank shaft.!!!!!!! pretty clever hey ????
I was going to send a pic but the file is too big

EDIT - Admin

__________________
When only the BEST will do!!

slippyr4

Nitro

I can kind of see your point, but I don't think anyone on this board appreciates your childish approach, vulgar langauge and unneccessary personal attacks against MyCroft.

If you want to behave like that, please do it somewhere else.

I'm sure others here will agree with me.

Jon

__________________
--
Signature is currently on holiday, returning soon.

nom

Hi - I'm new here, but I've been following this thread for some time.
The Mycroft arguments make sense, and the anti-Mycroft arguments are, well, abuse, or lack of understanding - quite reasonable (the lack of understanding) given the level of chemistry involved. This isn't school chemistry stuff and no-one short of a specialist should be expected to understand it - but try, it's interesting when you know!
And also remember that the 'experts' - independant testers and companies - can be wrong, especially as they frequently have their hands in someone's pockets... weigh it all up before deciding, don't just slam someone's (well educated) point of view.
Think, guys - this bloke might save your engine, or give it a few more years life. I think it's worth a bit of encouragement?
Well, I've put myself down for abuse as well now, I think

slippyr4

I don't like Nitro's attitude. It's not called for.

I'm not a petrochemist, but I did learn a reasonable amount about octane/octane boosting/octane testing when i was tuning mini's

The de facto standard method of testing octane is in a calibrated research test engine. Full Stop.

However, some funny little hand held device could also be accurate... I don't know.

The thing that does not make sense to me is this:- Knock = pre ignition, which means the charge self-detonates before the spark. Knock sensors are simply microphones. They can "hear" the occurance of every fire of the cylinders, and if that fire happens before the spark, then the ECU knows that knock is occuring.

Following on from that, the theory that Octane Boosters "fool" knock sensors just doesn't add up. Does it make them go deaf or something? At the end of the day, if knock is happening, it makes a noise, and a knock sensor will pick it up.

Jon

__________________
--
Signature is currently on holiday, returning soon.