Ducati Sporting Club UK
 
 
Thread Tools Search this Thread Display Modes
  #21  
Old 04-Feb-2006, 14:37
couchcommando's Avatar
couchcommando couchcommando is offline
Registered Forum User
Ducati Meccanica
 
Posts: 2,244
Join Date: Apr 2004
Mood: ooooh
I wasn't gonna share this but I've got some race air, I carry it in a cardboard box in the back of my van. If you want some just bring your airbox and £10 and I'll fill it up for ya, one airbox full should last one days racing and add 15hp, now don't say I never do anything for ya and form an orderly queue
Quote+Reply
  #22  
Old 04-Feb-2006, 17:38
Fordie's Avatar
Fordie Fordie is offline
Regional Organiser - BHCN
Ducati Corse
 
Posts: 3,276
Join Date: Aug 2001
Mood: Raring to Ride
Ya, Ive heared of this, its called HOT AIR most newbie racers swear by it , its likend to Bull **** you may find that usefull later on in the season 4D
Quote+Reply
  #23  
Old 04-Feb-2006, 19:07
ericthered40's Avatar
ericthered40 ericthered40 is offline
Registered Forum User
Big Twin
 
Posts: 1,698
Join Date: Jan 2005
Mood: renegade sexy racer
Quote:
Originally posted by couchcommando
I wasn't gonna share this but I've got some race air, I carry it in a cardboard box in the back of my van. If you want some just bring your airbox and £10 and I'll fill it up for ya, one airbox full should last one days racing and add 15hp, now don't say I never do anything for ya and form an orderly queue



Put me down for £60 Worth of that there super air will yu
Quote+Reply
  #24  
Old 04-Feb-2006, 19:22
domski's Avatar
DSC Member domski domski is offline
DSC Club Member
WSB Hero
 
Posts: 9,994
Join Date: Jan 2005
Quote:
Originally posted by ericthered40
Quote:
Originally posted by couchcommando
I wasn't gonna share this but I've got some race air, I carry it in a cardboard box in the back of my van. If you want some just bring your airbox and £10 and I'll fill it up for ya, one airbox full should last one days racing and add 15hp, now don't say I never do anything for ya and form an orderly queue



Put me down for £60 Worth of that there super air will yu

Save your money and just breathe into your airbox for 30 seconds

Quote+Reply
  #25  
Old 04-Feb-2006, 21:09
Dominic Clegg's Avatar
Dominic Clegg Dominic Clegg is offline
Registered Forum User
Big Twin
 
Posts: 1,354
Join Date: Sep 2005
Mood: DD 2006: 4th Top Rookie. DD 2007: 2nd Class B. DD 2008: 2nd Class B.
let me in here im the chemist

first of all as long as you can buy in in a normal filling station (the rules)

the more bhp you have the better the advantage of using high octane

the chemistry bit : higher the octane the more the fuel will compress before explosion hence use more of the cylinder hence higher bhp.
Quote+Reply
  #26  
Old 05-Feb-2006, 11:58
Rob B's Avatar
Rob B Rob B is offline
Registered Forum User
Ducati Meccanica
 
Posts: 2,263
Join Date: Aug 2003
Mood: I'm so happyyyyyyyyyyyy
What Monty said.

I've been running my race engine on Elf 4T (Superbike fuel) generally available to the public.....well maybe, as long as you shop at the pumps at Silverstone!... but the engine was developed and mapped to utilise its properties. Oh, and like CK said, it was only £70 for 20 litres!!!

Rgds, Rob
Quote+Reply
  #27  
Old 05-Feb-2006, 12:28
749er's Avatar
749er 749er is offline
Registered Forum User
Ducati Meccanica
 
Posts: 2,896
Join Date: Mar 2005
Mood: Auto racing, bull fighting, and mountain climbing are the only real sports ... all others are games
Quote:
Originally posted by jeff st4s
My mate in california nearly fell over when I said I was now using 97 octane not 95, he can struggle to find the minimum required to run his merc. 93.
In texas he says it can go down in to the mid 80's in octane, that why they all run big engines to get power, because the fuel is crap.

US fuel is rated on MON scale, we use RON scale, 95MON has a higher octane rating than 95RON
Quote+Reply
  #28  
Old 05-Feb-2006, 12:35
749er's Avatar
749er 749er is offline
Registered Forum User
Ducati Meccanica
 
Posts: 2,896
Join Date: Mar 2005
Mood: Auto racing, bull fighting, and mountain climbing are the only real sports ... all others are games
Higher octane fuel is less prone to detonation. On a modern car the knock sensor would kick in and retard your ignition, to protect the engine from det. With the appropriate hardware and software its possible to remap ignition and not just fuelling as a standard power commander does. So using a higher octane fuel with less risk of detonation means that the ignition can be advanced, and that on its own brings power gains.
Quote+Reply
  #29  
Old 05-Feb-2006, 15:05
Shazaam!'s Avatar
DSC Member Shazaam! Shazaam! is offline
DSC Club Member
Big Twin
 
Posts: 1,167
Join Date: Nov 2001
No. Using a slower-burning octane fuel and then raising the ignition advance to compensate - doesn't increase power.

There are two basic ways to increase the power of an engine. One way is to increase the amount of fuel and air being burned and another is to increase the efficiency of the burn itself. Raising the compression ratio of an engine primarily increases combustion efficiency. An engine will run most efficiently when the fuel/air mixture can be compressed as much as possible. More heat, more compression and the fuel/oxygen reaction will happen more quickly and more efficiently.

The main reason that high compression engines aren't manufactured anymore for street bikes is higher exhaust emissions. The extra heat produces more oxides of nitrogen (NOx). From a design point-of-view it also decreases reliability as the engine is under greater strain. So to increase the compression ratio of an engine designed for lower internal forces may require changes beyond high compression pistons.

The additional compression also produces higher cranking loads and additional blow-by. The higher cylinder pressures bypasses the rings easier so more combustion gases get by the rings into the crankcase. So consider using the Corsa breather canister and plumbing instead of the stock setup. You need to assure that the intake properly scavenges the crankcase of the increased blow-by without sucking any oil into the intake tract.

Further, you'll need to run higher octane gas to assure reliable high compression without detonation. Gas octane availability above 98 RON (92 R+M/2 in the US) is limited to aviation and race fuels, so most modern engine designs designed for high octane gas use knock sensors and computers that adjust the ignition timing on a real-time basis, so that they can be run nearer the detonation point without being damaged.

However, chances are that you'll be able to run a 13:1 compression ratio before exceeding the octane requirement of readily available pump gas.

Simply stated, when you raise the compression ratio you risk damaging your engine from pre-ignition. The resulting shock wave can shatter a four-stroke piston. So, you first need to make sure that the ignition timing is set properly to prevent engine knock under a variety of load, fuel, and environmental conditions that affect engine knock.

There are two primary factors which govern engine ignition advance. First, the constant time to burn results in a need for a linear increase in advance as a function of RPM. Second, higher RPM and loads lead to higher turbulence and faster burn times. So, the ignition advance should initially increase with RPM and then taper off and even decrease as the engine speed increases further. As a function of load (manifold pressure for example) the timing should decrease, ultimately being limited by engine knock and exhaust temperature. Before computers and solid state ignitions came into general use, manifold vacuum hoses and centrifugal advance mechanisms on distributors were used to advance engine timing.

On Ducati superbikes the ignition system is integrated with the fuel injection system to form a combined integrated engine management system which is operated by the electronic control unit (ECU). The ECU uses inputs from various sensors to calculate the required ignition advance setting and ignition high-tension coil charging time. There is no factory provision for adjusting the ignition timing on these models, although as you point out, there is a method using an aftermarket programmable EPROM or Power Commander to modify the ECU ignition map.

Consequently, to make the best power (safely) from a stock compression bike, you should use the lowest octane fuel recommended by Ducati - as a result of extensive testing. If it knocks under real-world high temperature and load conditions, use the next higher octane grade or try a different brand fuel.

[Edited on 2-5-2006 by Shazaam!]
Quote+Reply
  #30  
Old 05-Feb-2006, 20:33
multi600's Avatar
multi600 multi600 is offline
Registered Forum User
888 at Last !!!
 
Posts: 938
Join Date: Dec 2004
Mood: Hopefull
So why do they only state a minimum of 95 in the book but no max? if the fuel available at the pump can do damage to the engine??
Quote+Reply
Reply
  
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes
Postbit Selector
Switch to Vertical postbit Use Vertical Postbit

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Recent Posts - Contact Us - DSC Home - Archive - Top
Powered by vBulletin 3.5.4 - Copyright © 2000 - 2024, Jelsoft Enterprises Ltd. - © Ducati Sporting Club UK - All times are GMT +1. The time now is 21:23.