All finished! - Page 3

monkeycsl · 03-04-2012, 06:18 PM

The Gorilla · 03-04-2012, 06:37 PM

Hi,

Nathan- I was trying to illustrate that at
6250 rpm the S65 Short Stroke motor,
running 12.0 CR with 4 Cams etc
has its Torque curve already in decline.

Another point is that the Duty
cycle of the std S54 Fuel Injectors is maxxed
out at circa 375/380 BHP.

Regards,

The Gorilla.

mattCSLnut · 03-04-2012, 07:28 PM

Quote:

Originally Posted by DuncanR

Popcorn time !

You're not wrong there dUnk

_Nathan_ · 03-04-2012, 08:01 PM

Quote:

Originally Posted by The Gorilla

Hi,

Nathan- I was trying to illustrate that at
6250 rpm the S65 Short Stroke motor,
running 12.0 CR with 4 Cams etc
has its Torque curve already in decline.

Another point is that the Duty
cycle of the std S54 Fuel Injectors is maxxed
out at circa 375/380 BHP.

Regards,

The Gorilla.

Number of cams is just a function of the number of heads surely?

Rest of if no idea, maybe the op can chime in with his engine spec...

Any more info on the injector duty cycle as I have customers running far more than that on oem injectors (maxed out admittedly, Motec giving 100% duty cycle warnings but still well above your figures).

plug · 03-04-2012, 09:38 PM

I wonder could he have fitted a lightened flywheel? Would that have an effect on reducing torque?

cslsuperfan · 03-04-2012, 09:47 PM

any spare popcorn dunc!!

**alexk** · 03-04-2012, 10:09 PM

Seems a bit optimistic to me, if the engine only has airbox, cams and exhaust.

The Gorilla · 04-04-2012, 12:36 PM

Hi,

Quote-

''Any more info on the injector duty cycle as I have customers running far more than that on oem injectors (maxed out admittedly, Motec giving 100% duty cycle warnings but still well above your figures).

Nathan - I had an article here somewhere on it.
Will try and dig it out and send it on as it explained
why not to run fuel injectors at anything higher
than 80 % duty cycle at over 5 bar fuel pressure.
it was to do with the way spray patterns are optimised
at something like 75 psi.

Anything over and the fuel droplets can go to fine
which can cause hot spots etc.

There were a couple of exceptions, F430 springs to
mind with its 5 spray injector etc.

I think the std S54 is approx 0.52 BSFC [Brake Specific Fuel Consumption]

So if you do the figures on 380 BHP-

380 x 0.52 / 6 x 80
= 197.6 / 4.8
= 41.16 Lb [Req]

Stock Injectors, how ?

If you increase the Duty cycle to
99% then of course you fall back to 33lb
still not sure how this would work 100% on
stock injectors.

Of course you can Crank the Fuel Pressure
up to say 6 Bar, but it will be saturated
at idle, and the engine will be hunting like
a 'U' Boat Captain.

Not much use in a road Car but prehaps passable for
a Track Car.

I know of a certain CSL that idles just like that !!!!

Regards,

The Gorilla.

**Mark CSL** · 04-04-2012, 12:47 PM

**AlexGTT** · 04-04-2012, 01:07 PM

Hands looking slimmer Mark.

03-04-2012, 09:38 PM	#25
plug S2 - Picking it up Join Date: Jan 2009 Posts: 40 Casino cash: $2843	I wonder could he have fitted a lightened flywheel? Would that have an effect on reducing torque? __________________ No animals were hurt in the making of this signature.

03-04-2012, 10:09 PM	#27
alexk Driving it like I nicked it Join Date: Mar 2009 Posts: 2,785 Casino cash: $29970	Seems a bit optimistic to me, if the engine only has airbox, cams and exhaust. __________________ www.clubcsl.com - I am a BMW Motorsport fan ! My youtube channel is here

04-04-2012, 01:07 PM	#30
AlexGTT CSL Register Uber-poster! Join Date: Apr 2008 Location: Herefordshire Posts: 4,374 Casino cash: $8572	Hands looking slimmer Mark. __________________ CSL Register Alcoholics Anonymous Group Leader & Businessman of the Year '93! www.earleyengineering.com

03-04-2012, 06:18 PM	#21
monkeycsl S5 - Full Throttle BMX Park Champion! Join Date: Jan 2008 Location: essex Posts: 444 Casino cash: $18732

03-04-2012, 06:37 PM	#22
The Gorilla S5, Sport Off, DSC M-track Join Date: Apr 2008 Posts: 740 Casino cash: $14401	Hi, Nathan- I was trying to illustrate that at 6250 rpm the S65 Short Stroke motor, running 12.0 CR with 4 Cams etc has its Torque curve already in decline. Another point is that the Duty cycle of the std S54 Fuel Injectors is maxxed out at circa 375/380 BHP. Regards, The Gorilla.

03-04-2012, 09:47 PM	#26
cslsuperfan Driving it like I nicked it Join Date: Apr 2008 Location: wales Posts: 2,222 Casino cash: $19520	any spare popcorn dunc!!

04-04-2012, 12:36 PM	#28
The Gorilla S5, Sport Off, DSC M-track Join Date: Apr 2008 Posts: 740 Casino cash: $14401	Hi, Quote- ''Any more info on the injector duty cycle as I have customers running far more than that on oem injectors (maxed out admittedly, Motec giving 100% duty cycle warnings but still well above your figures). Nathan - I had an article here somewhere on it. Will try and dig it out and send it on as it explained why not to run fuel injectors at anything higher than 80 % duty cycle at over 5 bar fuel pressure. it was to do with the way spray patterns are optimised at something like 75 psi. Anything over and the fuel droplets can go to fine which can cause hot spots etc. There were a couple of exceptions, F430 springs to mind with its 5 spray injector etc. I think the std S54 is approx 0.52 BSFC [Brake Specific Fuel Consumption] So if you do the figures on 380 BHP- 380 x 0.52 / 6 x 80 = 197.6 / 4.8 = 41.16 Lb [Req] Stock Injectors, how ? If you increase the Duty cycle to 99% then of course you fall back to 33lb still not sure how this would work 100% on stock injectors. Of course you can Crank the Fuel Pressure up to say 6 Bar, but it will be saturated at idle, and the engine will be hunting like a 'U' Boat Captain. Not much use in a road Car but prehaps passable for a Track Car. I know of a certain CSL that idles just like that !!!! Regards, The Gorilla.