Hi, i know this has probably been posted before, but i tried searching and found nothing. Like the title says im wondering what the advantages of the RB4 is on hard track, because ive been testing it against the FXO and i cant seem to get the times about the same, and i thought they were meant to be pretty even cars, maybe im wrong.

thanks

Eagle

Advantages:
Fastest off the line
Best offroader
4WD
Easy to drive

Disadvantages:
Top speed
Acceleration on the move
High weight
4WD

Theres more, but thats all I can be arsed writing

thanks for the replys guys clears up alot of things, one thing though, VTiRoj, you said that 4wd is advantage and disad, i can see the advantage but what is the disadvantage?

thanks

Quote from Eagle05 :

thanks for the replys guys clears up alot of things, one thing though, VTiRoj, you said that 4wd is advantage and disad, i can see the advantage but what is the disadvantage?

thanks

4WD makes all 4 tyres drive, and the front 2 steer as well, so tyres get heated up quicker. Add that to the heaviness, and you wont have a long lasting car for endurance.

Not to mention a lot of the power is lost through all of the gearing and diffs and whatnot an AWD system has to put power through.

Also, @VT, the RB4 is not 4WD, it is AWD.

Quote from XCNuse :

Also, @VT, the RB4 is not 4WD, it is AWD.

I never quite understood the difference, but okay

Should be called a RBA then, RB4 is so misleading

I'd have to look it up, but some time ago I believe it was Tristan who gave the complete definition of the differences between the two, but the main differences are in the differentials, and that 4WD cars (which are not AWD which are all-time) have locked (or semi locked atleast) differentials which makes them harder to turn.

(this is all of course just a little FYI, not to be demeaning or anything )

I understand

Guess I'll go wiki into it

the RB4 is my fav car. every time i drive it i am always smiling. it is a very good "beginer" car but if you drive it for long enough you just get to enjoy the balance if the car. it can hold any line and with the flick of the wheel you can give it massive sideways action. it is just so forgiving in most corners it makes you think you can actually get a good time on all tracks. fair enough the other tbo cars have thier plusses too but none of them make me smile as much as the RB4

CAN I HAVE AN AMEN!?!?!?!?!

There is plenty of disadvantages, first off of you look at hp p/ton the rb4 is 201 i believe and FXO is 209, in the real world, it doesnt matter if its AWD, FWD, or RWD. regardless its all about hp/weight. The saying that the car is harder to turn in or its loosing power in the drivetrain is underlying to the fact that TBO class was a bit unbalanced, if you are good at setting cars up then you know that rb4 is just as good and has just as many disadvantages as the next. Its all about hp/ton and setup.

Quote from Eagle05 :

thanks for the replys guys clears up alot of things, one thing though, VTiRoj, you said that 4wd is advantage and disad, i can see the advantage but what is the disadvantage?

thanks

Oh almost forgot, now that patch X is comming out, the hp/ton should be equal. As of the W patch the hp still stands rb4=201... xrt=207(i think) fxo=209 you see the dissadvantage

Quote from dadge :

CAN I HAVE AN AMEN!?!?!?!?!

You can!

AMEN!

Will be even better in Patch X because you can actually win races in the TBO class with it.

Quote from XCNuse :

and that 4WD cars (which are not AWD which are all-time) have locked (or semi locked atleast) differentials which makes them harder to turn.

Correct, but by strict definition only the centre diff (or lack thereof I should say) is different.

4WD: No centre diff.
"Full time" 4WD: Centre diff (usually lockable) & low range capable
AWD: Centre diff, no low range

I have a new found love for the RB4, when I graduated up to a silver license in STCC / UKCT.

The way I set it up, it now behaves like a very powerful XFG; slight understeer into the corners, slight oversteer out. No oversteer drama, no plowing understeer, just....right.

Try this, see what others think:

Front clutch pack LSD:
Locking(power/coast) 60% - 50%

Preload: 160 Nm

Rear viscous LSD
Viscous Torque 10 Nms/Rad

Centre Viscous LSD
Viscous Torque 17 Nms/Rad

Front Torque split 50%

Now, some may make the "oh yucky" face when seeing my specs, but it makes the car very predictable and steady; you may not win every race (and you never will on setups alone) but you will finish in a respectable place.

Try it!

Set works for all Aston except Cadet and Club.

Amen sister!

lol i have used nothing but rb4 and ive been in the top 50 list for about a month now RB4 FOR LIFE!!!

i think you should watch the stcc videos on youtube or their website. you see the advantages of each car. allthough a RB4 won on south city????

STCC means we (the FXO's) start at the back

The RB4 one because although i was closing in, i just couldn't do it quick enough and fight through the traffic - it used to be in a straight fight the FXO ALWAYS owns on tarmac, now the FXO is lacking... balls

In general the front diffs of a 4WD are "open diffs" unless they are fitted with a diff locker, it's rather rare to see an LSD in the front diff of 4WD. However, most modern 4WD's have a rear LSD at the very least and some makes offer Front/Rear Diff Locks as an optional extra. A lot these days are also using the ABS to help control wheel spin, but that's completely different to a diff lock or LSD.

Some diff locks require the driver to press a button to engage the diff lock, some are automatic. When the manual diff lock is not engaged then the diff is "open". I don't know much about automatic ones (only ever used manual), I don't think it would be wise to fit one to the front diff.

To further explain a Centre Diff Lock, what that does is engage a fixed 50/50 drive split between the front and rear axles. Otherwise, when the Centre Diff Lock is not engaged the "Full-time" 4WD really just acts like a AWD vehicle which varies the drive between the front and rear wheels depending on wheel slip etc.

Quote from VTiRoj :

Disadvantages:
Top speed
Acceleration on the move
High weight
4WD

So basically... just "power" and "weight," which happen to be the only two real intrinsical disadvantages of AWD

FYI, auto diff locks are known as detroit lockers. Their default operating mode is as a locked diff. When one wheel is forced to turn faster on a sticky surface like tarmac, the faster outside wheel is allowed to disengage and freewheel whilst all power is sent to the inside wheel. But if one applies torque to the detroit locker again (e.g. flooring the throttle) it'll return to its normal locked diff mode of operation after about 15 degrees of wheelslip.

Detroit lockers are somewhat strange to those not used to them as they change the cars behavior from super tight and stable to absolutely loose whilst cornering. Turn in will feel tight, but as the vehicle starts to turn and the diff unlocks, there's a relatively sudden increase in yaw rate. But if one gets used to them, they do in a sense provide the ultimate performance as they have the traction of a locked diff without the mid corner speed penalties.

The RB4. Let's just say the TBO class hasn't got a chance to race fairly on tarmac until the turbo modeling and powerband issues are fixed. When was the last time you needed 5000rpm or more to get full boost from your 250hp 2.0L turbo engine? Power to weight ratio equality won't solve the issue, since each drivetrain thrives on different types of engine torque output. The FXO actually benefits from the peakiness and hopeless midrange, as it helps to alleviate front tire wear issues. The XRT needs smooth and consistent torque at midrange (4000rpm to 5500rpm) and excellent high rpm power (5000rpm to 7500rpm) to do its best and be as fun to drive as it should. The RB4 has the edge on traction and needs a strong midrange (3500rpm to 5500rpm) and very good high rpm (5500rpm to 7500rpm) power to really shine.

So in the end, it's not a simple matter of matching power to weight ratios. It's about giving the right kind of power curve for each car.

There is a post I agree with 100%.
It seems there is only a few of us who actually care about this issue. I stopped complaining about it ages after getting shot down for the theory being wrong and that if there was a problem it wasn't big enough to warrant the kind of recoding needed to fix such a minor issue.

So another one for the record.
The turbo modeling is crap. It needs to be fixed. It IS greatly improved from how it once was like back in the 0.04 days I think just before we moved onto 0.1 alpha where the turbo model was revised. I remember back in the day the turbo would slowly slowly boost up and would take up to 30 seconds to reach full boost. Then it was fixed and remains the way it is today but still. If I bought a 250hp road car that took till 5000rpm to come on full boost I would tell the manufacturer to shove it up their bum.
Just as an example. Mitsubishi Galant VR4. 1989 model with the 2 litre 4G63. These build strong boost from 2000rpm and even through the first two gears you'll be on full boost by 3000rpm. That's a damn near perfect example of how the RB4 should be. If you are to fit the turbocharger from the later Lancer Evolution III which has a much larger compressor wheel and housing then the VR4 had it becomes a little laggier and boosts later but boost starts coming on at 2500 and your on full boost and easily peak torque by 3500rpm - 4000rpm.

Quote from IceMan31x :

lol i have used nothing but rb4 and ive been in the top 50 list for about a month now RB4 FOR LIFE!!!

But you do know what car SparkyDave drives almost exclusively?

Quote from Crash Dummy :

There is a post I agree with 100%.
It seems there is only a few of us who actually care about this issue. I stopped complaining about it ages after getting shot down for the theory being wrong and that if there was a problem it wasn't big enough to warrant the kind of recoding needed to fix such a minor issue.

So another one for the record.
The turbo modeling is crap. It needs to be fixed. It IS greatly improved from how it once was like back in the 0.04 days I think just before we moved onto 0.1 alpha where the turbo model was revised. I remember back in the day the turbo would slowly slowly boost up and would take up to 30 seconds to reach full boost. Then it was fixed and remains the way it is today but still. If I bought a 250hp road car that took till 5000rpm to come on full boost I would tell the manufacturer to shove it up their bum.
Just as an example. Mitsubishi Galant VR4. 1989 model with the 2 litre 4G63. These build strong boost from 2000rpm and even through the first two gears you'll be on full boost by 3000rpm. That's a damn near perfect example of how the RB4 should be. If you are to fit the turbocharger from the later Lancer Evolution III which has a much larger compressor wheel and housing then the VR4 had it becomes a little laggier and boosts later but boost starts coming on at 2500 and your on full boost and easily peak torque by 3500rpm - 4000rpm.

Yes, this problem of LFS is so obvious yet so neglected, and I was also shot at quite a lot for mentioning a very important and obvious behavioral flaw. Seems like some sort of anti-turbo agenda...

Anyway, if they've struggled to model 2L turbo engines THIS long then why don't they just copy the data off RL engines? Better off with a good lookup table then trying to model turbo boost and powerbands by some equation that would give horrible results. IRL engineering, many things are so complex that there's no way to model them via equations without some horrifying simplifications, so what we CAN do is log lots of data and analyze things numerically. In fact, many equations used to model RL physical objects/processes are actually unsolvable analytically and can only be done numerically.

Quote from Jamexing :

Yes, this problem of LFS is so obvious yet so neglected, and I was also shot at quite a lot for mentioning a very important and obvious behavioral flaw. Seems like some sort of anti-turbo agenda...

Anyway, if they've struggled to model 2L turbo engines THIS long then why don't they just copy the data off RL engines?

When has anyone shot at you for mentioning flaws in turbocharger modelling?

I started a thread on it ages ago and it went quite well. (search for a thread called "boost modelling questions")

And I really seriously doubt that "they've struggled this long" rubbish. It's simply not at the top of the priority list, and hasn't been to our knowledge for ages. I'd be dissappointed if it wasn't addressed before S2 final, but who knows. Scawen has directly said that he knows the boost modelling has issues, so it's not like he doesn't know - he just has chosen to deal with other things.