Thanks for the answer.Quote:
Originally Posted by Mirek
But in a hypothetical situation, a driver can enter in, for example, Class 3 with a Class 6? Or stewards aren't going to allow it?
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Thanks for the answer.Quote:
Originally Posted by Mirek
But in a hypothetical situation, a driver can enter in, for example, Class 3 with a Class 6? Or stewards aren't going to allow it?
somebody here asked some time ago about weight distribution of S2000 car.
it's around 360 kgs each front wheel, 320kgs each rear wheel, with crew, spare wheel and some fuel
Hard to believe that M-Sport would reveal such detailed information about the engine.Quote:
Originally Posted by makinen_fan
Interesting reading, especially the section about the development of the DI engine. By this 30 million $ is used for the development of the Ford EcoBoost engine.
Referring to the few examples below both power and torque increases of a DI engine with the same or even less fuel (= air) consumption but that doesn't seems to be the case with the WRC cars. Can someone explain why?
“Mercedes-Benz is introducing new V6 and V8 gasoline direct injection engines for the CL and S Class that increase output by as much as 12.5% and decrease gasoline consumption by as much as 24%.”
“The design highlights of the 3.5-liter V6 in the S 350 BlueEFFICIENCY include a completely new air intake and exhaust system in conjunction with a variable resonance intake manifold and optimized inflow and backflow. Result: with the same displacement, the output compared with the previous 200 kW (272 hp) model rose by 12.5% to 225 kW (306 hp), while maximum torque has increased by 5.7 percent to 370 N·m (273 lb-ft) (predecessor: 350 N·m) and now is available over a broad engine speed range from 3500 to 5250 rpm.”
Green Car Congress: New Gasoline Direct Injection Engines in Mercedes-Benz CL- and S-Class Vehicles Cut Fuel Consumption By Up to 24%, Increase Output by Up to 12.5%
“Cadillac sells the CTS with both indirect and direct injection versions of its 3.6 liter V6 engine. The indirect engine produces 263 horsepower and 253 lb-ft of torque, while the direct version develop 304 hp and 274 lb-ft. Despite the additional power, EPA fuel economy estimates for the direct injection engine are 1 MPG higher in the city (18 MPG vs 17 MPG) and equal on the highway.”
Direct fuel injection - What it is, how it works - Direct fuel injection
“The advantage of direct injection is a more efficient engine. For example, Hyundai claims its 2.4 Theta II GDI gets 7 to 12 percent better torque than an equivalent port injection engine, while at the same time getting 10 percent better fuel economy.”
“The engine makes 198 horsepower and 184 pound-feet of torque. The current, port-injected 2.4-liter engine in the Sonata makes only 175 horsepower and 168 pound-feet of torque.”
Hyundai increases power, fuel economy with direct injection | The Car Tech blog - CNET Reviews
I'm no expert but in my opinion the biggest advantage of DI is that it allows the engine to run with high air-fuel ratio. That is good for the economy under low load but not that useful for racing engine where for maximum output You need richer AFR. I guess DI is somewhat more effective for WRC engine as well but I have no idea how much compared to usual way. Maybe Dimviii or someone else can educate us?
It would indeed be intresting to get an explanation to the engine issue.
The WRC and S2000 cars have and R5 will have three-way damapers (adjustable slow & fast compression + adjustable rebound). I don’t know if it’s the regulations that says that the dampers have to be three-way dampers or isn’t there any need for slow & fast rebound?
In the previous issue of “Vauhdin Maailma” JML told that the VW is more sensitive to changes in the set-up. As an example he said that with Ford he could do quirte a lot of “clicks” to the dampers before he could feel the difference.
Here is a link to a pdf which explains very nicely how the fast & slow compression and rebound works (8760 series beginning on page 11). I had been looking for this kind of explanation (words + pics) for a long time. :)
Btw, for newcomers. Here is the link to Antony Warmbold’s thread. In the first post a link to his blog with lot of interesting readings.
there is no such rule, that only 3 adjustments are allowed. but those are most important ones so most widely used. now there are a lot of dampers with additional - fourth adjustment - hydraulic bumpstop. most widely used is rubber bumpstop, then there is hydraulic bumpstop not adjustable and hydraulic bumpstop which is adjustable, it's common in Sachs or BOS dampers.Quote:
Originally Posted by OldF
So called "fast rebound" is not separately adjustable by a knob, it's often done by system like RCV (Reiger) or CAS (BOS) - when wheel is not touching the ground rebound "opens" fully and wheel is free to go down and touch the road again, it's good thing, but sometimes makes some trouble. Similar with for example Reiger CCV system - corner control valve - during cornering system detects which wheel is outer one and stiffens it's slow compression, giving less roll in the corner - it allows to use softer ARBs.
The problem is to create the smallest possible droplets, preferably gas before combustion begins. There is also a problem to create as equal mixture as possible in the combustion chamber. These are the problems one solve better with DI engine. (I think). These benefits should also prevails in a WRC engine.
Hope no one that really understand this, tear off his hair because of this explanation.
As far as I know, you can adjust drop-out with how much / little pressure one has before it triggers. Tein works this way in any case. Normally, a pressure of about 140 kg (or less) will be required before the drop-out occurs. This means that drop-out first occurs when the pressure is below 140 kg.Quote:
Originally Posted by br21
That is correct (if you`re reffering to RCV or CAS or whatever they name it) mostly they are spring load adjustable when the rebound needle opens, this is done in the topmount with a very small diameter spring able to withold a certain weight, by changing the spring rate you can adjust how soon/late the rebound needle opens!Quote:
Originally Posted by Coach 2
And actually the rebound doesn`t really open fully, it`s more less a certain amount/velocity of oil to run pass the shimstacks, for really fast damper speeds this small hole want be enough so something is always limited by the shimming!
yes, yes of course you are right, it was just shortcut in my thinking :)Quote:
Originally Posted by AMSS