New Honda Civic Type R (JA) ~ On sale this Friday ~

[centurion]

Originally Posted by foxfrc5

There's always talk about high powered Volvos having "too much power for that chassis" -- I think it started with the 850R back in the early 90s. I guess they mean the car has troubling delivering its power to the road, and scrambles for grip on straights and on the bends...?

Wow! That monster! Me and my kid brother always say - INTERCOOLER BRO! INTERCOOLER! CHECK IT OUT!

[Shaun]

Originally Posted by foxfrc5

There's always talk about high powered Volvos having "too much power for that chassis" -- I think it started with the 850R back in the early 90s. I guess they mean the car has troubling delivering its power to the road, and scrambles for grip on straights and on the bends...?

Originally Posted by caySman

When I casually mentioned that a certain chassis is overpowered, perhaps TOO casually, I usually mean to say that the speed which is too easily achieved by the car in a straight line is difficult to handle given a slightly aggressive driving behaviour.

By that yardstick, the extreme example is like the Estima 3.5 which has incredible ability to build speed over very short distances and in braking whether in a straight line or the corner, the suspension, brakes and chassis setup all conspire to give you extreme understeer, hard to brake, hard to feel the steering, rolling like a pig.

So when I read other people state `too much power for that chassis', I similarly think that they mean the same as I do.

I tend to define chassis as the actual frame of the car and separate it from other components of the car - brakes, aero, tires, those in the driveline, etc. So when I hear about a chassis being overwhelmed or overpowered, I picture it twisting. Bending and torsion forces from longitudinal acceleration do not come close to torsion forces from lateral acceleration - unless you get into extreme power and grip that no production street car does. The ones that come closest run mid/rear engined RWD configurations which greatly reduce torsion effect from long. accel.

Take a non-positive-aero car that is perfect in current state, then double or triple its power without positively changing dynamic patch properties, and the chassis will not be any more stressed because forces acting on it are not any higher. Longitudinally it may be held at peak stress for a longer time since peak acceleration can be maintained across a larger speed range. Tires and driveline can be overwhelmed, but the chassis is fine. Fatigue is cycle related, not duration related. Plastic deformation doesn’t occur unless the original forces were into that range, in which case the problems have nothing to do with the new level of power.

More power may indirectly (more power > need for more traction > more tire > more lateral accel > high peak forces ) lead to an overwhelmed chassis, but only through changes in grip levels either via aero or tire or patch changes, but I don’t think this is what most writers mean when they say a chassis is overpowered. Most times I believe they mean the tires, brakes, and/or suspension, isn’t matched to the power and/or mass of the car.

I can’t remember how much the 850R weighed or how much tire it had. I recall it looked real big and heavy. Maybe it was a double hit of large mass, high power, and under speced systems that gave it problems. It was one car with presence though. It or some variant of it, raced in the BTCC I think. 850Rs IMO were one out of only three production based sedans that have real presence – others being the World Challenge CTSV-R s and Vipers.

Originally Posted by xkrim3

allow me to ot a bit and cross over from another thread. so this means me and my buddy can build a tube frame and lup in a rb26dett, use it in a non-regulated time attack, or just have some fun round the track without killing ourselves? would it be obscenely expensive to sort out the handling/suspension bits for this setup? we are still toying with this idea

I’m not sure if you’re planning for a featherweight single seater type car in the 400-700kg range, or a stripped out sedan in the 800-1200kg range, or how much power you intend to run. In any case, fun track and personal time attack car isn’t going to require high levels of efficiency. It will be fun and fast, regardless of whether it is well sorted or not - within broad limits. It won’t cost much to get it within the ballpark. You have to decide how good a car you want out of what you put into it in time and money. If something fun and fast does it then no worries. If getting max speed and efficiency out of the total package to the point of being able to enter it in say MME if you guys at some point choose to, does it for you, then you need to consider a greater range of factors, and slightly more carefully. If you want you can start a new thread to collect input and I’ll contribute too.

[centurion]

OK Shaun. I was going to dispute your definition of `chassis' - that it is not within the mainstream media's meaning, but come to think of it, I think the mainstream media has it wrong - just like me, they have confused CAR with CHASSIS.

So I mean - CAR, not chassis. The CAR is overpowered.

[xkrim3]

Originally Posted by Shaun

I’m not sure if you’re planning for a featherweight single seater type car in the 400-700kg range, or a stripped out sedan in the 800-1200kg range <snipped> I’ll contribute too.

around 2100lbs with engine in. i will take up your offer thro private consultation. hope you dun bill by the hour. TIA

[foxfrc5]

Originally Posted by Shaun

More power may indirectly (more power > need for more traction > more tire > more lateral accel > high peak forces ) lead to an overwhelmed chassis, but only through changes in grip levels either via aero or tire or patch changes, but I don’t think this is what most writers mean when they say a chassis is overpowered. Most times I believe they mean the tires, brakes, and/or suspension, isn’t matched to the power and/or mass of the car.

I guess what everyone should have been saying was "too much power to put down via FWD and 205 series tires..." bearing in mind we're talking early 90s tire technology here.

[tsentsan]

The CTR seems to be quite under-spec'ed compared to what the folks in UK get. Gone is the HID, Brembo brakes and Satnav... and $105K... Might as well get a Euro R or Focus ST.

[Shaun]

Originally Posted by caySman

OK Shaun. I was going to dispute your definition of `chassis' - that it is not within the mainstream media's meaning, but come to think of it, I think the mainstream media has it wrong - just like me, they have confused CAR with CHASSIS.

So I mean - CAR, not chassis. The CAR is overpowered.

ok, take it easy... your caps are worrying...

Originally Posted by xkrim3

around 2100lbs with engine in. i will take up your offer thro private consultation. hope you dun bill by the hour. TIA

sounds good, will work out the details.

Originally Posted by foxfrc5

I guess what everyone should have been saying was "too much power to put down via FWD and 205 series tires..." bearing in mind we're talking early 90s tire technology here.

Yup not enough tire, and the FWD conundrum of increased requirement for placing mass over the driven wheels for better longitudinal acceleration but ending up with a nose heavy car, or optimizing mass distribution for lateral acceleration by taking shifting mass rearward and off the nose, but compromising long. accel. Same problem exists with RWD cars, but to a lesser degree because of direction of weight transfer under positive long. accel. , helps instead of hurts.

[R33Devil]

Originally Posted by foxfrc5

I don't think I know a single track junkie who runs a stock vehicle.

coming soon to a race track near you...

the yellow grasshopper!

[foxfrc5]

Originally Posted by Shaun

Yup not enough tire, and the FWD conundrum of increased requirement for placing mass over the driven wheels for better longitudinal acceleration but ending up with a nose heavy car, or optimizing mass distribution for lateral acceleration by taking shifting mass rearward and off the nose, but compromising long. accel. Same problem exists with RWD cars, but to a lesser degree because of direction of weight transfer under positive long. accel. , helps instead of hurts.

Out of curiosity, what's your preference for your own daily driver? FWD, RWD or 4WD?

[foxfrc5]

Originally Posted by R33Devil

coming soon to a race track near you...

the yellow grasshopper!

I think that car was always meant to serve double duty as a street car and frequent track day tool... :-)

I was referring to cars that are meant as daily drivers over 90% of the time, like the CTR.