[wardfan]

what exactly does the chassie part of the car consist of?

[wingkey1]

Originally Posted by Racer Duck

Thunder,

The front wheel drive causes a couple different things: one you need to be aware of, and one your driver needs to do.

1. It's gonna push, ya can't stop it.
2. Driver needs to run mostly front brake and slow down early before getting into the corner, then on the gas as early as possible (it won't turn unless he/she is on the gas - thus the push.)

RD, already admitted here we've zip zero direct experience with FWD oval equipment so I'm kinda going with the flow. The thread segment here got our interest up and we bumped in to some FWD competitors who had experience in RWD as well. I took opportunity to ask what was thought to be the more significant set up challenges. Response was - gotta work hard to overcome constant inherent tendency towards loose through the turns.

Now having already seen your - "It's gonna push, ya can't stop it", and having my previously described "zip zero" direct experience, we had to seek explanation.

What was heard was that the drive wheels having all of that fine extra weight on them (engine, transmission, more?), decked out with them fine "grippy" race tires tends towards allowing the front too much control throughout the turn beginning near the instant any crank is put in to the steering. Went on to explain that as weight begins its shift towards the front entering the turn, the already too light rears get even lighter and they exhibit desire to swing out (the old classic loose). Now if I wasn't already moving towards feeling confused, the explaination I received went further to say one method employed was bias towards the rear brakes. Now we were beginning to feel brain numb. Did recover enough to blubber the question - why to the rear? Explaination was that by starting with rear slow down the vehicle is a bit delayed from the dive forward which is undesireable because it simply helps the front take over too early in the turn. It (rear bias) also allows the fronts to be more free to rotate further into and through the turn. Rotation stops, control stops, skid begins. While my mind wanted the mouth to ask whether anti-locks might not help avoid - well wasn't really sure where I would go or what I could do with that info anyway.

As mentioned at VERY beginning and earlier post, we know from direct personal experience NOTHING around this and having what seem to be exact opposite observations set before me - fried brain.

[bears9]

this is not a NASCAR question but could cou please answer it

are all F1 races on road courses ?

[thunderfoot]

Fried Brain. Join the club. Some tell me the track banking will play a part in the rear wanting to go south when I want to go north. So one tells me stiffer rear springs. I tend to think not. We want a little body roll here to transfer weight but not to pick up the left rear. Rules will not let us lock the differential on front drive. So I dont think tire stagger will play such a roll as it did in my rear drive locked with a spool. Now one past champ who had a very fast VW, told me go in hard but not deep, roll in the throttle and if the rear starts to slip a bit mash on the throttle and point the wheels where you want to go and it will pull you out of it. That goes against all of the race car physics I have ever known. In my old car I tried to "Earnhardt it" and all I found out was I aint no Dale!

[Racer Duck]

Originally Posted by wardfan

what exactly does the chassie part of the car consist of?

that's a very good question .. we throw that term around all the time never thinking some people have no idea what we're talking about.

according to wikipedia: the term chassis means the frame plus the "running gear" like engine, transmission, driveshaft, differential and suspension. A body (sometimes referred to as 'coachwork"), which is usually not necessary for integrity of the structure, is built on the chassis to complete the vehicle.

for a race car, the roll cage and other superstructure (bars for strengthening the frame via the roll cage) are counted as part of the frame.

[Racer Duck]

Originally Posted by bears9

this is not a NASCAR question but could cou please answer it

are all F1 races on road courses ?

As far as I know all F1 courses include both left and right turns. All F1 races but two are run clockwise: those being the Brazilian GP at Sao Paulo and the Turkish GP at Istanbul. Also the only real street circuit is the Circuit de Monaco, used for the Monaco Grand Prix, though some circuits are laid out on public roadways such as the Canadian Grand Prix at Montreal. By and large, all F1 courses, except those mentioned, are built strictly for competition and are what we, Americans, would call "road courses."

[Racer Duck]

Originally Posted by wingkey1

RD, already admitted here we've zip zero direct experience with FWD oval equipment so I'm kinda going with the flow. The thread segment here got our interest up and we bumped in to some FWD competitors who had experience in RWD as well. I took opportunity to ask what was thought to be the more significant set up challenges. Response was - gotta work hard to overcome constant inherent tendency towards loose through the turns.

Now having already seen your - "It's gonna push, ya can't stop it", and having my previously described "zip zero" direct experience, we had to seek explanation.

What was heard was that the drive wheels having all of that fine extra weight on them (engine, transmission, more?), decked out with them fine "grippy" race tires tends towards allowing the front too much control throughout the turn beginning near the instant any crank is put in to the steering. Went on to explain that as weight begins its shift towards the front entering the turn, the already too light rears get even lighter and they exhibit desire to swing out (the old classic loose). Now if I wasn't already moving towards feeling confused, the explaination I received went further to say one method employed was bias towards the rear brakes. Now we were beginning to feel brain numb. Did recover enough to blubber the question - why to the rear? Explaination was that by starting with rear slow down the vehicle is a bit delayed from the dive forward which is undesireable because it simply helps the front take over too early in the turn. It (rear bias) also allows the fronts to be more free to rotate further into and through the turn. Rotation stops, control stops, skid begins. While my mind wanted the mouth to ask whether anti-locks might not help avoid - well wasn't really sure where I would go or what I could do with that info anyway.

As mentioned at VERY beginning and earlier post, we know from direct personal experience NOTHING around this and having what seem to be exact opposite observations set before me - fried brain.

wing, I'm sorry I confused you .. what your "friends" told you is all true, but (ya knew that was coming, didn't ya?) think of the problem in simple terms and at specific places around the track.

• aproaching the turn - gotta slow down .. fast .. if rear bias helps, do it. my thought was the rears are already doing nothing but keeping the rear bumper off the ground so they aren't gonna be much help in stopping when the weight transfers forward .. unless you're running significant rear weight (50% or more...) too much rear bias will cause the lightened tires to lock up and then when you turn, they have no traction so will swing around .. loose.
• entering the turn - now the front wheels are carrying the load .. if you try to turn with out applying power, it don't turn .. pushes bad. this is where RWD has an advantage: you can control the rear end by applying power or not; with FWD if you let off the gas it pushes so ya gotta stay on the gas .. those front tires are clawing at the track when you're under power, they're "pulling" you thru the turn. but when you let off, there's no more "pull" so now all that weight that's been transfered to the front is now wanting to go straight no matter where the tires are pointed. Sticky tires help, but they don't change the laws of physics. now about the "loose" rear end: any car that's "thrown into a corner" will exhibit loose tendencies; the trick is to "drive" into the corner under power and let the rear end follow.
• let's back up for a second to discuss some differences between FWD and RWD: when you have FWD the front wheels are pulling you around .. you're gonna go where ever they are pointed, the rears dance along behind without doing much to help in the handling dept; when you have a RWD the front wheels are trying to turn, but the rears are driving straight ahead, you can cause the rear tires to loose traction and thus swing out and help get the vehicle pointed where you want to go .. with RWD the front tires are being pushed around by the rear tires. These differences are why FWD cars are safer in slick conditions. Have you ever tried to steer a car on a slick road while you have your foot on the brakes .. easy to do with FWD, a nightmare with RWD.
• OK, now we've entered the corner and should be on the gas: accelerating as hard as we can without causing the rear end to swing out; weight is transferring back to the rear giving them more traction; the problem we face here is the left front getting light (all the weight is to the outside and moving rearwards); so ya gotta do whatever it takes to keep that LF down, roll bar, high rebound on LF shock, whatever works for you.

now, go back and think about what your friends said in light of these things I just pointed out. What I saw when I read your post was guys who are putting patches on a problem, not fixing it. Luckily they stumbled on using the rear brakes to slow themselves down before entering the corner. But their loose condition is either caused by a high rear roll center or not enough body roll to put weight on the RR to keep it planted and probably exacerbated by their pitching the car into the turn rather than driving it in. Something I would check is their static rear weight percentage - I'd bet it's low.

Originally Posted by thunderfoot

Fried Brain. Join the club. Some tell me the track banking will play a part in the rear wanting to go south when I want to go north. So one tells me stiffer rear springs. I tend to think not. We want a little body roll here to transfer weight but not to pick up the left rear. Rules will not let us lock the differential on front drive. So I dont think tire stagger will play such a roll as it did in my rear drive locked with a spool. Now one past champ who had a very fast VW, told me go in hard but not deep, roll in the throttle and if the rear starts to slip a bit mash on the throttle and point the wheels where you want to go and it will pull you out of it. That goes against all of the race car physics I have ever known. In my old car I tried to "Earnhardt it" and all I found out was I aint no Dale!

Thunder,

generally more track banking will increase traction in the corner. The reason is simple: centrifugal force. You also have to run heavier springs when ya run on high banks. re: your very fast VW driver .. exactly what I said, ya gotta control the car with the throttle, but it's exactly opposite from what you'd do with a RWD. As strange as it seems, with FWD when ya get into trouble, gas it! let the front tires pull you out of trouble rather than the rear tires pushing you into trouble as with RWD.

[wardfan]

Originally Posted by Racer Duck

that's a very good question .. we throw that term around all the time never thinking some people have no idea what we're talking about.

according to wikipedia: the term chassis means the frame plus the "running gear" like engine, transmission, driveshaft, differential and suspension. A body (sometimes referred to as 'coachwork"), which is usually not necessary for integrity of the structure, is built on the chassis to complete the vehicle.

for a race car, the roll cage and other superstructure (bars for strengthening the frame via the roll cage) are counted as part of the frame.

Now it makes more sense when there is talk about a winning chassis. I had the impression it was what you described as the framework. Since chassis includes the engine, etc. I understand now why drivers talk about their favorite chassis.

[Racer Duck]

wing and thunder,

not sure if I made any sense with the previous post .. it'd been a long day, took the LM to practice, still engine problems but think it's rocker arm related (will change them out tonight) and the quick change we pulled out of the SLM has a loud noise in it (we never got to run it after it was rebuilt last) we think the problem is the locker (DPI Black Gold), but don't have the stuff to check it. Pulled the quick change last night, replaced the locker with a spool and reinstalled. anyway by the time I got to replying to posts I was toast.

so, let me begin again.

wing, I think the guys you talked to gave you the strait scoop as it applies to them. what I think is they have some problems they're band-aiding by the adjustments they are making. when you understand the physics it becomes apparent.

thunder, as you know, as the banking increases, the amount of lateral g's doesn't increase, only the downforce on the springs, shocks and tires. it doesn't matter whether it's FWD or RWD or AWD, the effect is the same. if you fail to match the springs and/or shocks to the banking, however, you can end up with a very loose situation, i.e., the springs are too stiff or the shocks are too stiff in compression, thus are not allowing the tires to grip the track.

that said, let me re-cover the differences between FWD and RWD from a purely physical standpoint:

1. the FWD car is "pulled" along by the front tires. which ever way the front tires are pointed it will go that way. the rear tires have nothing to do but follow along and hold the rear of the car off the ground.
2. the RWD car is "pushed" along by the rear tires. the direction the car will go is mostly determined by which way the front tires are pointed. however they can be overcome by too much push from the rear tires (that's where the term "pushing" came from.)

any time a tire looses traction, for whatever reason, it no longer has any control in determining where the car is heading. tires loose traction because of several reasons: locked up brakes, too many lateral g's, the tire is too hard, the surface is too slippery/slick/smooth. as you improve any of these, the traction is improved.

whether FWD or RWD, the driving tires traction and power applied determine not only how fast the car is going, but also how close it is to loosing traction. when the driving tires apply force in a direction different from the direction of travel, they cause a force to be applied to the car that tries to overcome the momentum direction.

if the steering tires are not the driving tires (RWD) and the steering tires have sufficient traction, the vehicle will change direction and if the driving tires do not have enough traction they will slide sideways in the direction of their momentum (what we call "loose".)

if the steering tires are the driving tires (FWD) and they have sufficient traction, they will cause the vehicle to turn. the rear tires will follow as long as they have sufficient traction to overcome their momentum; if they do not, they will slide sideways in the direction of their momentum ("loose".)

with a RWD car having sufficient rear weight helps a car turn because it keeps the driving tires "hooked up". this is usually around 50% or more. with a FWD car having sufficient rear weight helps a car turn because it keeps the driving tires "hooked up". (sound familiar?)

now, here's the main thing about FWD. unlike RWD, the front tires traction cannot be overcome by the rear tires. the only things that can cause the front tires to loose traction are: too much driving power or too many lateral g's (and, of course the characteristics of the track/road surface). also unlike RWD, when the front tires slide sideways, the fix is driving power .. enough to overcome the loss of lateral traction. neither braking nor applying less power will allow the tires to regain traction.

now think about the contact patch of the tire. with a racing tire, that contact patch is much larger than with a street tire. AND the tire tread compound is softer to promote traction at the expense of tire "mileage". so, in all ways the racing tire is "better" for performance applications. but there's something hasn't changed much, if at all. the ratio of the side to side measurement of the tire contact patch to the front to back measurement. because the side to side measurement is so much more than the front to back measurement, the best traction is always achieved by the tire rolling and the least traction is always when the tire is sliding sideways.

when you put together this information you can see how the driving power applied to the front tires of a FWD car will increase it's cornering ability while at the same time, an equal amount of power applied to the RWD car will cause it to not want to turn ("push")

the things you do to improve cornering performance with either type of car are the same: locate the tire that's loosing traction, decide whether it's a power problem or a weight problem (too much or too little) and take an appropriate course of action. you'll be fastest when you find the perfect compromise between the two.

I hope this has cleared up any confusion I may have generated by previous posts.

[Racer Duck]

Originally Posted by wardfan

Now it makes more sense when there is talk about a winning chassis. I had the impression it was what you described as the framework. Since chassis includes the engine, etc. I understand now why drivers talk about their favorite chassis.

unfortunately most drivers don't know one engine, transmission or differential from another - as long as it pulls hard, shifts smoothly and doesn't seem "lacking" in any way, they don't care .. but they do know what their favorite chassis "feels" like: it's like a comfortable pair of tennies; does what they want when they want and how they want. some drivers want to feel every bump in the road and every twitch the car makes (they call it "input") while others want the car to insulate them from that stuff and give them a Cadillac ride. Some want the steering very quick and others want is slow. all the combinations imaginable set just so is what makes a chassis a favorite .. and, strange as it seems, another built at the same time by the same people on the same jigs using the same components will be somehow different - it's one of the great mysteries about race cars that nobody has ever figured out how to eliminate.

[Bob Tanner]

Originally Posted by Racer Duck

a short story about our frustration with it: we were at the big race of the season at our local track in 2004; big bucks to win and guys from all over with their first class equipment. we pitted next to Freddie Query. during a down time, we struck up a conversation with him .. told him the car's pedigree and that we couldn't find the handle. he said: "if that's one of Rich's cars, don't feel bad .. no body can drive Rich's cars but Rich!"

<slap!> Pontiac. After I looked at it and looked at the darn grill I saw the error of my ways. One of my faults; since I know that they're only hung sheet metal, I just look at the general outline of the cars.

I always liked to see Freddie run in the Snowball. I haven't been to one since 2004, though. Arguably one of the best pavement short track races in the country (undoubtedly the best one in December!?) Does he still run out of Mooresville?

Speaking of big name chassis and how they can be difficult, back in the 70's my brother-in-law got hold of an old Ed Howe chassis (How's THAT for dating myself? Bet you haven't thought about the "Green Hornet's name in awhile.). He had it under Mustang metal and he said he never got a handle on the thing. Of course, it was an old chassis, probably ridden hard and put up wet.

[simple simon]

what happens if a driver repeatedly ignores a black flag ? ..... would they throw a yellow to deal with him ?

seems with so many intense personalities there must have been at least one instance when a driver said 'to heck with that' when he got the black flag


(Bob must remember some such instance)

[thunderfoot]

When the black flag is flown and the driver ignores it, the race officials will stop scoring the car. No more laps are counted and credited to that car.

[Racer Duck]

Originally Posted by simple simon

what happens if a driver repeatedly ignores a black flag ? ..... would they throw a yellow to deal with him ?

seems with so many intense personalities there must have been at least one instance when a driver said 'to heck with that' when he got the black flag


(Bob must remember some such instance)

officially, failure to ignore the black flag is cessation of all scoring. Upon continued ignoring of the black flag, forfiture of all winnings and points. Finally, banned from competing in the series for X amount of time up to life.

Originally Posted by thunderfoot

When the black flag is flown and the driver ignores it, the race officials will stop scoring the car. No more laps are counted and credited to that car.

it becomes a problem when the driver won't leave the track. normally the pace car will lead all competitors onto pit road and a red flag will be waved. the black flagged driver will be ordered to vacate the track. failure to do so will be cause for arrest by the local law enforcement. no matter how fast the car is, it can't get away if they don't open the gate and the driver will be liable for all damages caused by his actions after black flagged and told to leave the track. it's a problem that doesn't happen often but when it does there's an escalation with each refusal that will ultimately lead to jail time, heavy fines and being banned for life.

[Racer Duck]

Originally Posted by Bob Tanner

<slap!> Pontiac. After I looked at it and looked at the darn grill I saw the error of my ways. One of my faults; since I know that they're only hung sheet metal, I just look at the general outline of the cars.

I always liked to see Freddie run in the Snowball. I haven't been to one since 2004, though. Arguably one of the best pavement short track races in the country (undoubtedly the best one in December!?) Does he still run out of Mooresville?

Speaking of big name chassis and how they can be difficult, back in the 70's my brother-in-law got hold of an old Ed Howe chassis (How's THAT for dating myself? Bet you haven't thought about the "Green Hornet's name in awhile.). He had it under Mustang metal and he said he never got a handle on the thing. Of course, it was an old chassis, probably ridden hard and put up wet.

though we are partial to Lefthander chassis, a fellow competitor in San Antonio, also a field tester for Howe, helped us get our car setup right. Tommy Grimes (the Texas Tornado) knew his stuff 'cause the next race we did the best we'd ever done. While at his shop he showed us some developmental stuff on his car that was currently in the test stage. We decided we really liked Howe's upper control arm design and his Y-pipe, muffler and turn down were also at the top of our list. Tommy said whenever we wanted to change over he'd help us get it setup right. Ed Howe's stuff has been around a long time and I don't know anybody that dislikes what he puts out .. though they may prefer a different builder's design. In fact I see "Howe" on 9 out of 10 hubs on Late Models and Super Late Models. they are the standard.

as far as I know Freddie is still in Mooresville. I seem to remember seeing his name on an entry list for a race in Alabama or Tennessee earlier this year and it said he was from Mooresville.