Ian Carr

I feel like i am in my thermodynamics class again... hahah

gt37vgt

i think waynes piont is as many engines approach 450 or more whp the people tuning them are so happy with them selfs they start to believe there could be no thermal management or combustion issues . and if a motor pings it will fail no matter how fancy the pistons or studs

333pg333

What's the difference between pinging and knock then?

gt37vgt

well same but i knock sometimes comes after damage like a spun bearing .
i feel pinging short for preignightion is more appropriate

HIGHBOOST

It's not really measured, but calculated. Take the total volume underneath the combustion chamber at BDC, and divide that by the total volume at TDC.

BTW, great topic, great reading material!

333pg333

I knew that pinging is pre-ig but it can precede knock but not necessarily?

blown 944

really they are one in the same Patrick, just different terminologies.

Yes it can precede knock, knocking your pistons right through the cylinder wall

Acetylene

Very enjoyable thread.

CPR

OH...BY THE WAY...

THIS THREAD SUCKS WITHOUT PICS.

David Floyd

Bri Bro

OMG Dave, after that, I need to get an antidote picture

CPR

BB,
Thanks....my eyes were bleeding from Floyd's insanity

JohnKoaWood

I know this is a little old, But I do remember someone asking for Special Tools mod list, turns out he has it posted online, now who is willing to sort the BS from the Real S?

CEP 2.5 alusil block with CEP/SKI(Brett) Mahle "slipperskirt" pistons/rings
4 stage C.E.P. dry sump, remote Wix, 3 gallon Peterson tank, stock oil pressure and oil temp guage
Porsche crank/rods - worked by Joe@DCE
Vitesse big valve/ported 8 valve head-further modified valves by Joe@DCE
Vitesse MAF/Motronic semi-sequential injection
Vitesse SMT6 fuel/timing controller with modified timing
Vitesse wasted spark ignition
NGK BPR8ES .025
SFR stage 2 / 4-1 headers/x-over v-band to full T4 turbocharger end
SFR short runner/large plenum intake manifold
SFR 3" T4 V-band downpipe
SFR/Special Tool 75mm Motronic-compatible throttle body
Special Tool 1000 ci. intercooler
Special Tool 2.75/3.00" ic pipes (reverse flow) Forge adjustable racing bypass
Large full T4 turbo
Lindsey 3" exhaust wth Borla 40944
Lindsey complete fuel rail@ 3 bar static
Cometic 3 layer stainless gasket
Milledge 503/475
Adjustable cam gear 1 degree advance today
2 Bosch 044 fuel pump (in series currently)
Siemens 72
Tial 38mm
Lindsey black **** controller
4 channel egt
Zeitronix datalogger - wideband/boost/rpm/maf/tps/knock(soon)
Large Setrab oil cooler
And of course - all of the COUNTLESS experimental parts that Lart has sent me for a pittance just to help me. Thanks Luis.

http://www.dragtimes.com/Porsche-944...lip-12751.html

Stock:
Engine: 151 Ci. Porsche
Turbos: T4
Supercharger:
Boost Control: Manual
Boost Pressure (psi): 2 Bar
Intercooler: 1000 Ci.
Nitrous System: NO
Nitrous Shot:
Pistons (rotors):
Port:
Rings (seals):
Heads: Vitesse
Connecting Rods: Porsche - worked
Camshaft: Milledge
Throttle Body: SFR/Tool
Intake & Air Filter: SFR
Headers / Downpipe: SFR - Burns
Midpipe:
Exhaust: T4/3 inch
Carburetor: Na
Computer ECU Chip Upgrade: Motronic
Battery:
Ignition: Wasted
Spark Plugs: NGK
Fuel Injectors:
Fuel Pump: 2 x Bosch 044
Gas: Pump/aromatic blend
Pulley:
Transmission: Porsche
Clutch/Torq Conv: KEP/ceramic
Differential: Porsche
Radiator:
Flywheel: Fidanza
Shifter: 993
Gears: AOL code S
Suspension: Bilstein Escort cup race
Wheels: 993
Brake Rotors/Pads: Porsche turbo S
Tires: Street radial Michelin
Weight with driver (lbs): 0
Track:
Record Modified: November 26th, 2007

Chris White

I’m starting to feel like the picky guy…
Actually they have different meanings (but sometimes the same result)
Detonation (knocking)
• Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.
Pre-ignition
• Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.
I have a really interesting paper posted on my web site – check it out, lots of good info (a little to big to post here!)
http://www.944enhancement.com/html/knock_ping.html

blown 944

very good read, I stand corrected.