Does anybody know if the “gear changing” light is at red limit or is it at revs (plus gear changing delay) that gives the best torque to the drive shafts for the next gear compared to previous?
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Does anybody know if the “gear changing” light is at red limit or is it at revs (plus gear changing delay) that gives the best torque to the drive shafts for the next gear compared to previous?
the red light is not at limiter but some hundrets rpms before limiter.
So, it doesn’t have anything to do with the optimum torque from wheels?
explain please,torque is from engine.Quote:
Originally Posted by OldF
Oldf means the red light flashes at the point when max torque is measured at the wheels in relation to engine rpm.
For example if peak torque is reached at 5200 rpm and rev limit is 7500, does the shift light flash at 5200, 5500, 7000, or 7500 rpm?
If I am understanding correctly...
Thanks Typath107,
It’s sometimes difficult to explain technical things in English when it’s not your native language. :confused:
That’s what I tried to explain. Engine torque is of course always the same on same revs but the revs on which the max torque is on the wheels, depends of the ratio of the gearbox / final ratio.
Current gear ratio divided by next gear ratio times peak engine torque revs (For example 2nd gear ratio / 3rd gear ratio * engine peak torque revs).
What You need is to use biggest possible power all the time through the gear. Torque is a value which is good for understanding the engine characteristics but it's often wrongly interpreted because it changes through gear ratios as You said. Power keeps same through gears (except some looses of course). Basically if You have any of the two curves You don't need the other. It's much simpler to understand the engine from power curve in my opinion because peak power is always the best You can get while peak torque not.
You shall shift the way You have always the biggest possible area under the power curve through rpm range You use. For example You have an engine which has peak torque at 4000 rpm but peak power at 8000 rpm. For best performance You shall stay around the 8000. Where You would shift up depends on the shape of power curve but it will be somewhat after peak power.
That’s correct. The torque at the drive shafts is highest (with the correct gear) when the power from the engine is around peak power.Quote:
Originally Posted by Mirek
I made few years back some calculations to see how it looks on a graph. The Mitsu example is not the best one because the peak torque is little below 3300 rpm and peak power is already at 3600 rpm. The Subaru has the peak torque at 3500 rpm and peak power at 4400 rpm.
Mitsu
http://i267.photobucket.com/albums/i...ps746b0df7.jpg
Subaru
http://i267.photobucket.com/albums/i...ps5b522695.jpg
With a little googling I found three different ALS systems.Quote:
Originally Posted by Mirek
- Air bypassing the throttle body to the intake manifold. Fuel from the fuel injectors and retarded ignition. [/*:m:2mmy6vq0]
- Air directly to the exhaust manifold. Fuel from the fuel injectors and retarded ignition. [/*:m:2mmy6vq0]
- Both air and fuel directly to the exhaust manifold and retarded ignition. [/*:m:2mmy6vq0]
I assume that it is the last one used by WRC cars (and the loudest one), or is it?
I wrote that post bad, sorry. It shall be that with R5 all the air must go through combustion chamber (and if I understand right it must go through throttle as well) not directly to the exhaust. The fuel as well must be supplied from engine fuel injectors. I don't know if WRC cars have fuel injection into exhaust but sure they have air supply line to the exhaust.
I'm no expert in this...
Very good write up of the Subaru "rocket" anti lag system.
Beyond the Dyno: External Combustion Rocket Anti Lag System + JDM Spec C Impreza STI
Very nice article and videos!
Quote:
Originally Posted by makinen_fan
Quote:
Originally Posted by "Mirek
What could be the difference between Citroen and Ford? I would imagine that the springs, dampers, anti-roll bars, diffs and camber could have same set-up, stiffness etc. so the difference between the cars must be in the basic design (geometry) of the suspension in spite of simple regulations. At least Ford have more positive caster compared to Citroen.Quote:
Originally Posted by Sulland
Mikko once said that the design approach of Citroen is different but he did not won’t to go into details. JML said in “Vauhdin Maailma” that the body shell of the Fiesta moves/rolls more compared to the Polo and that the Polo is more sensitive to changes in the set-up. Juho commented in an interview that he start to feel sick because the Ford swings so much.
I think the most noticable difference is suspension travel, it looks much more at Fiesta (Polo too). So generally speaking DS3 looks much more "stiffer", imo more difficult to handle and looks like more prone to understeer, while Fiesta seems to be more driver friendly as he can throw it all the way round.Quote:
Originally Posted by OldF
Another noticable difference looks suspension geometry. I noticed only on Polo rear shock's angle is opposite to front ones, it looks like it is designed for heavy breaking on front and hard acceleration with more downforce on the rear (probably this helps for not so much understeer, asuming overall setup is same for every car), because of this geometry. this could be the whole difference in car handling in corners.
It is also possible I just talk rubbish... :)
Shock absorber top mounting points, i.e. the angle of the shocks on Polo is taken from Fabia S2000. VW admitted that openly. Nevertheless I believe the overall suspension travel of Polo is bigger than of Fabia. VW commented that the limit for suspension travel was in reliability of driveshaft joints under such extreme angles. The main reason why shocks are placed under such angle is to make them longer. M-Sport made them parallel like // while Škoda opposite like A. It's interesting that 208 R5 has them placed in Fiesta style //. The negative thing of the long travel is massive changes of geometry in extreme suspension situations as simple McPherson struts suffer a lot from this phenomena. There are also much higher forces in steering with the big castor angle. Visible body movement of Fiesta can hardly help overall performance, at least I can not imagine how. Maybe it helps the feeling of the driver, I don't know. Despite that all I believe the main difference between Citroën and Ford is in differential settings. In times of C4 WRC they even used 40/60 torque split on asphalt.
My thinking only:
Stiffer bodyshell same as stiffer springs, which is not good at icy or snowy surfaces. Longer suspention travel has nothing to do when there´s tarmac.
Back in the time driving my Ascona with stiff suspension and absolutely no grip on winterconditions was no good at all ( and that was in rdinary traffic going to the annual inspection of authorithies).
Back then I learned that smother suspention was a better thing in winthertimes even in raceconditions. Having said that it was on roads that wasn´t on tarmac.
Stiffer suspension and overall setup are better on asphalt, yeah CMR 2005 was my teacher several years ago :D
Hi
Some points regarding bodyshell and wheel geometry.
A stiffer bodyshell is almost always an advantage, in general the stiffer bodyshell the softer and more precise all wheel setups will be and also alot more sensible to fine adjustments. It`s almost impossible or very difficult to use the chassis softness as an advantage. Think of it: how can you adjust the chassis stiffness.
For sure. I didn´t mean stiffer bodyshell would be bad. Just that in very slushy conditions you really can tell what a stiff suspension can do to the handling, when as i RMC, you have tyres that are not apropriate to the weather conditions...Quote:
Originally Posted by AMSS
for some years now M-Sport cars were designed with more body roll than other cars. it's because of mounting points of the suspension, but also because of softer springs, dampers, etc.
True, but after NORF pre event test last year they visibly stiffened the setup on the cars based on drivers demands, and the results were instantly better as well..
I think suspension mounting points would have to be more associate with body pitch than roll. Body roll is controlled by spring rate, ride height and antiroll bars. But the pitch has a lot to do also with suspension geometry and anti-dive characteristics induced in wheel kinematics (i.e. wheel moving backwards/forwards as it moves up/down).Quote:
Originally Posted by br21
Also I am not sure if this was the case with Focus vs C4. I remember C4 being softer generally than the Focus, especially diving under breaking.
Have M-Sport developed a Fiesta R5+? If so, what is the main its main point of difference from the R5?
What it shall be? There is 3 years long homologation cycle for R5 cars. They can not come with some big changes in such short time period. If You speak about FIA events...Quote:
Originally Posted by Plan9
There is R5+ already for British championship I presume, Wilson junior tested it last year on some event. Probably he meant that, yes it is developed, but I have no idea will be used by someone. Concerning differences, I think it had bigger restrictor and 6 speed gearbox AFAIR.
R5+ is something similar to S2400, I mean planned for promotion/national events, etc. R5+ kit contains bigger turbo, bigger restrictor, etc. M-Sport plan to have conversion kits available for customers, but AFAIK those kits are not ready yet.
I'm really waiting for Mexico (and especially Portugal) to see Mikko's speed on gravel... Interesting to see whether he'll use the new stiffer setups or go back to his old ones.Quote:
Originally Posted by AMSS
Focus was supersoft, I remember one corner combination over crest and through a dip in certain testroad. In 2010 Focus bottomed basically every time (the plastic/carbon fibre piece behind front wheel arc was destroyed during the day) through that corner/dip. A year later Fiesta seemed to be a bit harder as it didn't bottom out on any of the runs I spectated there. Corner here in 1:58: http://www.youtube.com/watch?v=VWTIxREKX-M#t=119 (usually the line was a bit more from inside). Compare with Focus: http://juhake.kapsi.fi/JML_Day2/album/ 6th and 7th picture.
Quote:
Originally Posted by stefanvv
Thanks You both.Quote:
Originally Posted by br21
Or MW lobbying FIA. “Look what we have made. Wouldn’t this be nice for the next WRC formula (because we can build it)”. ;)Quote:
Originally Posted by br21
http://www.m-sport.co.uk/m-sport-news/f ... odels.html
“Based on the standard Ford Fiesta R5 which launched earlier this year, the Fiesta R5+ incorporates a modified turbo and air-intake system. The standard 32mm restrictor has also been replaced with a 34mm example which provides the engine with an extra 30hp. Not homologated for FIA championships, the Fiesta R5+ is intended for national series.”
Few videos.
http://www.youtube.com/watch?v=o0yGUSNYeE0
http://www.youtube.com/watch?v=hGcJbJHItAI
http://www.youtube.com/watch?v=LN_Kxy4HX18
On a Finnish forum a forum member told that his brother has modified a group N Mitsu to the Finnish FIR R 4WD group regulations. With E85 fuel and 34 mm restrictor (otherwise 35 mm). Dyno results with 1,5 bar boost, 375 PS / 720 Nm.
Definitelly more powerful than regular R5. In hands of more capable drivers, this will be very exciting car to watch. I like these experiments M-Sport are making with bigger engines. It'll be a shame if those cars will never be used.Quote:
Originally Posted by OldF
Here in Bulgaria we used to have 2 drivers driving ethanol Mitsus before 2013. They beated all S2000 on regular bases, even our multi-champion Iliev, but some crashes prevented better results.Quote:
Originally Posted by OldF
It sounds quite possible. Some time a go one engineer told me that for gr.N Impreza with 33 mm restrictor a proper E85 set engine meant something like +40 Hp and +60 Nm compared to usual racing petrol one.
Is there any concern about running out of fuel at the end a group of stages since more fuel is required? Also are teams there buying e85 or mixing their own? And if mixing, are using regular petrol from a pump or race fuel?Quote:
Originally Posted by Mirek
It was with a car from Belgian championship, I don't know exact regulations for the fuel - if they use their own or how it is. In the national championship I think the risk of running out of fuel isn't that big as the loops aren't that long but anyway he told me the consumption was some 20% higher.
Probably bigger tank goes with the engine pack
Is tank size not regulated? Even with our open rules here, capacity must be no greater than stock.Quote:
Originally Posted by stefanvv
May be it is, no idea. But in that case stock trunk should be enough to supply E85 cars for longer passes.Quote:
Originally Posted by TyPat107