I took the kids to see Cars at the movies this week - It's school holidays here in Qld. I'd recommend it to all of you. The kids enjoyed the cartoon car characters - I enjoyed spotting all the car culture references in the background......
No salt in this movie
Yes I am again bored at work!! Anyone want any research done?? Big Gaz has me checking out exhaust lengths for Primary and Secondary pipes....
CARS - The movie
Moderators: DLRA, Rob Carroll, OLDtimer, outbacktrev, Peter Noy
-
Dr Goggles
- Posts: 1315
- Joined: Tue Jul 05, 2005 11:23 pm
- Location: Right behind you Chief !
Night Row
"O2NCH3/CH3OH is a contributing factor in the manufacturing of Aluminium Oxide. Legs out bed and expensive ash trays.."
I think beer and curry are a contributing factor in the manufacturing of O2NCH3.............
I think beer and curry are a contributing factor in the manufacturing of O2NCH3.............
...few understand what I'm trying to do , but they vastly outnumber those who understand why..
-
Reverend Hedgash
- Posts: 448
- Joined: Wed Oct 19, 2005 2:19 pm
- Location: Hobart, Tasmania
Research
Lynchy,
while you are on sizing pipes, what are the best lengths, diameters, for a Commodore V6? We are up to building our exhaust and need to know the ideal to aim for but it is going to be tight in the tank...
We are aiming for naturally aspirated for the first year, then thinking blown etc.
Ta,
Rev.
ps I liked the pinstriping tattoo on the rear end of the Porsche in Cars, nice touch.
while you are on sizing pipes, what are the best lengths, diameters, for a Commodore V6? We are up to building our exhaust and need to know the ideal to aim for but it is going to be tight in the tank...
We are aiming for naturally aspirated for the first year, then thinking blown etc.
Ta,
Rev.
ps I liked the pinstriping tattoo on the rear end of the Porsche in Cars, nice touch.
DLRA Member#412
-
DON NOBLE
- Posts: 742
- Joined: Thu Dec 22, 2005 8:37 am
- Location: PAIHIA , BAY OF ISLANDS , New Zealand
Re: Research
ah easy , 6 x zoomies . 3 each side 
Reverend Hedgash wrote:Lynchy,
while you are on sizing pipes, what are the best lengths, diameters, for a Commodore V6? We are up to building our exhaust and need to know the ideal to aim for but it is going to be tight in the tank...
We are aiming for naturally aspirated for the first year, then thinking blown etc.
Ta,
Rev.
ps I liked the pinstriping tattoo on the rear end of the Porsche in Cars, nice touch.
NOW LIVE IN NEW ZEALAND
RED NISSAN WAGON 1986 # 281
2002 F/PRO 125.4 MPH RECORD
2003 F/PRO 140.2 MPH RECORD
2005 F/GC 137.9 MPH RECORD
2006 F/GC 141.1 MPH RECORD
1/4 mile ( drags ) @ Willowbank 14.15 @ 97.61 mph August 2006
RED NISSAN WAGON 1986 # 281
2002 F/PRO 125.4 MPH RECORD
2003 F/PRO 140.2 MPH RECORD
2005 F/GC 137.9 MPH RECORD
2006 F/GC 141.1 MPH RECORD
1/4 mile ( drags ) @ Willowbank 14.15 @ 97.61 mph August 2006
Dirty
The Flame front is as follows:
"The advancing of fuel reacting from a source of ignition. During normal combustion there is only one flame front which advances from the spark plug to the outer edges of the combustion chamber. During abnormal combustion multiple flame fronts can start, which leads to detonation."
Yes - it is the definition of what a flame front is - you need to be more specific.
Oh - I'm not bored anymore, my boss is back at work!
The Flame front is as follows:
"The advancing of fuel reacting from a source of ignition. During normal combustion there is only one flame front which advances from the spark plug to the outer edges of the combustion chamber. During abnormal combustion multiple flame fronts can start, which leads to detonation."
Yes - it is the definition of what a flame front is - you need to be more specific.
Oh - I'm not bored anymore, my boss is back at work!
Rev
I think Don has the most correct answer.
There is no way on the Jag to route the pipes any way apart from out the side of the car behind the front wheel but ahead of the door. The car will be tooooo low to do this any other way. So my answer to Big Gaz was get the primaries right and then the secondary length will be dictated by the 12" left to the hole in the guard.
I too suggested zoomies as this would be the coolest option.
BTW - BG has found a bloke who charges hourly rate to build a cage for the car. He will do it on weekends AND will do it at Gaz's shed. It will also be scheduled for a weekend that I am in Sydney to help out. How good is that!!
I think Don has the most correct answer.
There is no way on the Jag to route the pipes any way apart from out the side of the car behind the front wheel but ahead of the door. The car will be tooooo low to do this any other way. So my answer to Big Gaz was get the primaries right and then the secondary length will be dictated by the 12" left to the hole in the guard.
I too suggested zoomies as this would be the coolest option.
BTW - BG has found a bloke who charges hourly rate to build a cage for the car. He will do it on weekends AND will do it at Gaz's shed. It will also be scheduled for a weekend that I am in Sydney to help out. How good is that!!
Rev
I found a website a while back that looked to hold some promise:
http://headerdesign.com/index.asp
You can register to gain access to a header design calculator that would likely be useful if you have a fair degree of info for your engine. It also contains some good theory.
I've found some other calculators but they require much more info to perform the task.
BTW - It doesn't like the numbers I punched in for the blown Cleveland. I think it might have thought I was playing silly buggers.....
I found a website a while back that looked to hold some promise:
http://headerdesign.com/index.asp
You can register to gain access to a header design calculator that would likely be useful if you have a fair degree of info for your engine. It also contains some good theory.
I've found some other calculators but they require much more info to perform the task.
BTW - It doesn't like the numbers I punched in for the blown Cleveland. I think it might have thought I was playing silly buggers.....
Ok Lynchy,
My idea of flame front meant the speed of witch the combustion travelled,
Dyno ing one of my early motors on VP14+ we found that didn't really matter what we did the power always dropped off at 11700rpm i'm almost certain we didn't have detonation or valve float issues, as we tried a few diffrent thing like timing, fuel mixture and diffrent valve spring pressures, in fact we took valve installed height out and made more power but it still nosed over at 11700rpm, we put this down to flame combustion speed, similar motors on diffrent fuels with higher lift cams will rev a lot harder and the power curve is at a higher level,
If you now how hard you can rev a V8 with a 4" stroke i can calculate it back to my 66mm stroke, blown and drip fed..
Cheers dirty
My idea of flame front meant the speed of witch the combustion travelled,
Dyno ing one of my early motors on VP14+ we found that didn't really matter what we did the power always dropped off at 11700rpm i'm almost certain we didn't have detonation or valve float issues, as we tried a few diffrent thing like timing, fuel mixture and diffrent valve spring pressures, in fact we took valve installed height out and made more power but it still nosed over at 11700rpm, we put this down to flame combustion speed, similar motors on diffrent fuels with higher lift cams will rev a lot harder and the power curve is at a higher level,
If you now how hard you can rev a V8 with a 4" stroke i can calculate it back to my 66mm stroke, blown and drip fed..
Cheers dirty
Don't Worry, It only seems Kinky the first time..
DD
Does this help?
Using high octane fuel for an engine makes a difference when the engine is producing its maximum power. This will occur when the intake manifold has no air restriction and is running at minimum vacuum. Depending on the engine design, this particular circumstance can be anywhere along the RPM range, but is usually easy to pin-point if you can examine a print-out of the power-output (torque values) of an engine. On a typical high-rev'ving motorcycle engine, for example, the maximum power occurs at a point where the movements of the intake and exhaust valves are timed in such a way to maximize the compression loading of the cylinder; although the cylinder is already rising at the time the intake valve closes, the forward speed of the charge coming into the cylinder is high enough to continue to load the air-fuel mixture in.
When this occurs, if a fuel with below recommended octane is used, then the engine will knock. Modern engines have anti-knock provisions built into the control systems and this is usually achieved by dynamically de-tuning the engine while under load by increasing the fuel-air mixture and retarding the spark. Here is a white paper that gives an example: http://dinancars.com/whitepapersFile.asp?ID=9 . In this example the engine maximum power is reduced by about 4% with a fuel switch from 93 to 91 octane (11 hp, from 291 to 280 hp). If the engine is being run below maximum load then the difference in octane will have even less effect.
Not quite what you asked for but may be relevant to your experience.....
Does this help?
Using high octane fuel for an engine makes a difference when the engine is producing its maximum power. This will occur when the intake manifold has no air restriction and is running at minimum vacuum. Depending on the engine design, this particular circumstance can be anywhere along the RPM range, but is usually easy to pin-point if you can examine a print-out of the power-output (torque values) of an engine. On a typical high-rev'ving motorcycle engine, for example, the maximum power occurs at a point where the movements of the intake and exhaust valves are timed in such a way to maximize the compression loading of the cylinder; although the cylinder is already rising at the time the intake valve closes, the forward speed of the charge coming into the cylinder is high enough to continue to load the air-fuel mixture in.
When this occurs, if a fuel with below recommended octane is used, then the engine will knock. Modern engines have anti-knock provisions built into the control systems and this is usually achieved by dynamically de-tuning the engine while under load by increasing the fuel-air mixture and retarding the spark. Here is a white paper that gives an example: http://dinancars.com/whitepapersFile.asp?ID=9 . In this example the engine maximum power is reduced by about 4% with a fuel switch from 93 to 91 octane (11 hp, from 291 to 280 hp). If the engine is being run below maximum load then the difference in octane will have even less effect.
Not quite what you asked for but may be relevant to your experience.....
G'Day All
Regarding header design I"m now building V8 supercar engines for a living. These engines are at a point where if you change spark plug heat range you almost have to change pipes to optimize. I am not kidding.
We cannot generalise what pipe length will suit what motor. You are best to build a tri Y design on unblown V8's ( doe'nt know what suits V6)
but unless you want to try a multitude of pipes on a dyno there is no exact answer for your engine.
On our budgets if it looks right it is right and this will get you 90% of the way to what suits your motor
Teas getting cold
Seeya Chris
Regarding header design I"m now building V8 supercar engines for a living. These engines are at a point where if you change spark plug heat range you almost have to change pipes to optimize. I am not kidding.
We cannot generalise what pipe length will suit what motor. You are best to build a tri Y design on unblown V8's ( doe'nt know what suits V6)
but unless you want to try a multitude of pipes on a dyno there is no exact answer for your engine.
On our budgets if it looks right it is right and this will get you 90% of the way to what suits your motor
Teas getting cold
Seeya Chris
Acme Racing #251