Help - Way too much self centering

[Gary Slahor]

I raced a Vee for the first time this past weekend, and really enjoyed it...... but there's one thing I really would like to fix, if possible.
When accelerating away from the apex of a corner, I have to REALLY fight to unwind the steering wheel slowly and evenly. The front wheels want to get back to straight ahead, like right now ! .... and it takes everything I've got to hold it from going off the outside of the corner. It's not pushing..... just a really strong desire to self center.
In my other formula car, I would check/suspect excessive caster, but I don't know if this is even something that can be adjusted in a Vee.
Anyone have any suggestions ?
TIA............Gary

[FVRacer21]

I raced a Vee for the first time this past weekend, and really enjoyed it...... but there's one thing I really would like to fix, if possible.
When accelerating away from the apex of a corner, I have to REALLY fight to unwind the steering wheel slowly and evenly. The front wheels want to get back to straight ahead, like right now ! .... and it takes everything I've got to hold it from going off the outside of the corner. It's not pushing..... just a really strong desire to self center.
In my other formula car, I would check/suspect excessive caster, but I don't know if this is even something that can be adjusted in a Vee.
Anyone have any suggestions ?
TIA............Gary

can you tell us what car you have? And what tires you are running?

[Matt Clark]

I raced a Vee for the first time this past weekend, and really enjoyed it...... but there's one thing I really would like to fix, if possible.
When accelerating away from the apex of a corner, I have to REALLY fight to unwind the steering wheel slowly and evenly. The front wheels want to get back to straight ahead, like right now ! .... and it takes everything I've got to hold it from going off the outside of the corner. It's not pushing..... just a really strong desire to self center.
In my other formula car, I would check/suspect excessive caster, but I don't know if this is even something that can be adjusted in a Vee.
Anyone have any suggestions ?
TIA............Gary

You ended up with Jonathans car, right?
Definitely check your caster... he ran a TON of it for a while. In the Vees, we change caster by shimming the beam.

[problemchild]

The advantage of buying a developed proven car is that it is a developed proven car. Unless you find a specific problem (as in broken or misadjusted part) then you are not "fixing" an issue but undeveloping a proven car. Driving a FV is a unique experience. I would confirm with previous drivers/owners that the car is as desired, and if so, give yourself a chance to get used to the car.

"Being too responsive" is not a common commentary of first time FV drivers.

[Gary Slahor]

Thanks for the replies. Yes, I acquired Jonathans Protoform. P3 I think it's very well setup and ran well right out of the box. Jonathan was a great help with setup and tuning, for my first weekend.
Although I realize that it will take some getting used to, and I don't plan on changing much, but I would like to make it easier to steer.
It is extreemly fatiguing to drive and I believe you're never going to go fast if you're not comfortable driving.
I'll get it up on a level platform and measure it up and see what the caster is, and maybe get some more guidance from the group.

[Matt Clark]

Thanks for the replies. Yes, I acquired Jonathans Protoform. P3 I think it's very well setup and ran well right out of the box. Jonathan was a great help with setup and tuning, for my first weekend.
Although I realize that it will take some getting used to, and I don't plan on changing much, but I would like to make it easier to steer.
It is extreemly fatiguing to drive and I believe you're never going to go fast if you're not comfortable driving.
I'll get it up on a level platform and measure it up and see what the caster is, and maybe get some more guidance from the group.

After some particularly hot & miserable Nationals we were around him at, I remember him saying it was a hard car to deal with. He looked beat.
I am not sure how much room you have, and I know you are familiar with this from the F1000, but can you get a larger steering wheel in there? Changing the pitman arm or spindle arm lengths would help leverage also, but will obviously change your steering ratio.

[pacratt]

On a side note... and not to get too preachy... but in a vee, you should be starting to accelerate right before or as you begin turning.
Accelerating from the apex means you're coasting through half of the corner and throwing away alot of momentum (which vees need to go fast).
Coasting in and then punching the accelerator may cause a seemingly heavy or push feel in the steering.
That's also not taking into consideration how the castor, camber & toe settings may be affecting it.
No offense...just a thought (I always figure the more input you get, the more you have to consider).
Glenn

[Gary Slahor]

Thanks again for the suggestions. Jonathan was very clear on the need to get the power down as soon as you turn in. I began to get on the throttle sooner and sooner and the car behaved much better under power then off throttle. Unwinding the steering wheel coming off the apex took almost everything I had to keep the wheel from pulling out of my hands. I figured I was just a wimp, but perhaps I could deal with a bit less caster........ my arms and shoulders are telling me it was a workout.

[FVRacer21]

****double post***

[FVRacer21]

I like the idea of the largest steering wheel you can put in - I know the Protoforms and similar like 9” or less but if you can go to 10 without dropping the wheel in your lap, try it. Also, make sure you are not straining to reach the sw. Hands out looks good in 60’s F1 cars but there is a reason NASCAR drivers look like little old ladies behind the wheel. easy to put a spacer between wheel and quick disconnect if steering column is not adjustable.

Does the car have stock steering arms or short quick or zero Ackerman? Is the pitman arm extended? All that can raise the force to turn the sw.

if you have a camber gauge you can measure the castor or check the angle on the beam and compare to other Protoforms. More caster might give some camber assistance but people have told me the new spec tire is more tolerant than the old gum balls.

don’t change anything major until you understand the whole setup.

my 2 cents. ????

ChrisZ

[Jnovak]

How about an actual caster number from someone out there?

[Ed Womer]

If what I was told a VW road car has 6 or 7 degrees of built in castor but I never measured it. What means is the top tube of the front beam is in an angle with the top tube back 6-7 degrees behind straight up and in relation to the floor of the chassis. A lot of FV chassis have 6 degrees built into the frame meaning it already has that angle so if you mount the beam by bolting it to the frame it will already be at that angle.

I build my cars with the front of the chassis at a 90 degree angle from the bottom which provides 0 castor. The biggest effect provides is a self centering effect which is why it fells like you are driving an old truck without power steering. I was asked by a fellow racer a long time ago to drive his car and the biggest thing I remember was the serious effort needed to steer the car.

The best thing you can do is with the car on a level surface use a cheap gravity angle gauge and measure the angle. I am making a guess it is at least 6 degrees or even more. If so a 1/4" shim behind the top tube and frame will eliminate around 3 degrees so a 1/2" shim will change it 6 degrees.

I have let a few others drive my car and with 0 degrees castor they always said they had to drive the car in a straight line because the 0 degrees castor and 1/16" total toe in in the front the car was very easy to turn and didn't always go straight on an uneven surface.

Some believe excessive camber makes the front tire work better but that is an opinion. If you don't want to drive the car in a straight line but let it do it itself then that is a trade off and it will make you tire quickly while driving. I have seen Jonathan sit in the car after a race because he was to tired to get out. If that is what you want or think is better then you will have to live with it, you can't have it both ways.

As another note excessive toe in will also provide a similar effect so you need to check that. Some people with the high castor actually have slight toe out to allow the car to turn in easier. so you need to check that as well.

Ed

[Hardingfv32]

Is Jonathan still racing in FV?

Brian

[Gary Slahor]

Yes, I believe he will be at Kershaw..... in the FV of his own design

[Gary Slahor]

OK..... It's not extreemly precise, but after zeroing my digital level on the concrete floor, then placing it across the two beams, I got a reading of 80.7 degrees........... so subtracting from 90 gives 9.3 degrees of caster. Sounds like a lot to me. Is this the way the FV community measures caster ?

I plan to test next time with less caster. Does anyone have a suggested starting point for a P3 ?

And what effect would reducing caster by several degrees have on the handling in general ?

TIA............Gary

[Gary Slahor]

After thinking about it further, I zeroed the level on the main frame rails under the seat, to get a beam angle relative to the frame, and it was within a few tenths of the other reading............. so I'd say approx 9 degrees of caster.

[Jnovak]

I don't remember what caster I had on my old lynx. but it was very close to 5 degrees, it was pretty competitive !

[Steve Davis]

If it's really NINE.. I can see why you got tired turning the wheel. Add to that, the likelihood that Jonathan DOES have 'quick steer' on that car. 9 sounds pretty high to me.
sd

[Gary Slahor]

Thanks for the feedback. I'll try shimming the beam to 5-6 degrees for my next outing, and see how it behaves.
Gary

[nrider42]

When you increase caster you effect the camber on the wheels when turning don't you? You effectively add negative camber to the outside wheel....this should help turn in. At a cost of increased steering effort. Life is a series of compromises.

I am used to running 4 ish degrees of caster on the 944 and it helps high speed stability and I told myself it helped turn in as well. I tell myself a lot of things.

--Nate

[Steve Davis]

Gary,
Considering all the things that will probably be affected by changing the beam castor that much, I'd suggest you take this process in steps.

#1. Call Jonathan and talk to him about your issues. He is somewhat of a 'pioneer of radical thinking' when it comes to his cars. He might have significant input about your issues with the steering.

#2. Make a SMALLER change to the car first. Making big changes to a 'presumably properly operating racecar' is fraught with potential issues you probably haven't considered (since you've never driven or worked on a vee before). It would be wise, I think, to not make as big a change as you are suggesting. Moving from ~9 degees to ~5 degrees is a MONSTER change - with attendant MONSTER side effects.

#3. The side effects of a beam camber change are MANY .. and MANY are highly dependent on the others. You will find a change in castor will affect - ride height, toe steer, pitman arm clearance to feet, front DIVE under braking and might also potentially induce the dreaded FV 'tramping' experienced by MANY --- usually with no known cause or immediate solution and it will drive you CRAZY trying to get it right again. There might also be a front SHOCK change that would affect your handling.. which MIGHT 'echo' to the rear shock tuning... and also rear CAMBER tuning. A well handling car can go SOUTH in a big hurry.

I'd suggest that, if you really want to make a castor change, you start with a much smaller change. Maybe 1 or 2 degrees at the most and then drive the car and see how it feels. You will probably still have to 'fix', ride height, toe and foot box issues to get comfortable in the car again. (I'm assuming, since you made no mention of it) that the car 'fit' you reasonably well - no foot area issues, no shifter/shifTING issues, no roll bar clearance issues, etc).

Consider also, that a vee is NOT going to handle like an FB or FC (you are coming from FB, aren't you?). If you only have ONE weekend in the car, it's very possible that in your 2nd weekend, you'll find that the car is MUCH easier to drive than you remember. The VW steering box is NOT a rack & pinion and that change alone is a significant change in how the steering effort FEELS to the driver. As mentioned above, if your steering wheel is too far away from you, your steering effort will FEEL much higher. Moving the wheel towards you by as little as 1/2" can make a significant difference... if you have the lap and elbow room to make that change. (do that with an extension to the steering rod, or spacer to the wheel itself, rather than trying to make the change in the footwell - it'll be easy to change back if you don't like it). I'd certainly make THAT change (if possible) before considering changing to a larger steering wheel.

Jonathan did VERY WELL in that car you have, so I'd be careful about making changes other than minor comfort changes before you make big changes to the car itself.

At any rate, welcome to FV.
And remember, an FV is not a REAL RACECAR .. it's a 1964 VW 'bug' sporting a fancy racing paint job.

Steve, FV80
edit.... in regards to 'reach to steering wheel', I made a very small change to my current vee when I got it 2 years ago. I 'adjusted' the seating position by about 1/2 inch (created a 'pocket' for my butt in the seat) - that took me from feeling VERY UNCOMFORTABLE in the car, to being really cozy and comfortable. It also changed my reach to the steering - which didn't affect ME, but might affect you. I also added some side bolsters to 'tighten' me in the car .. which introduced a problem getting easily into 4th gear (elbow clearance) that took me several races to get squared away. YMMV.

[problemchild]

#3. The side effects of a beam camber change are MANY .. and MANY are highly dependent on the others. You will find a change in castor will affect - ride height, toe steer, pitman arm clearance to feet, front DIVE under braking and might also potentially induce the dreaded FV 'tramping' experienced by MANY --- usually with no known cause or immediate solution and it will drive you CRAZY trying to get it right again. There might also be a front SHOCK change that would affect your handling.. which MIGHT 'echo' to the rear shock tuning... and also rear CAMBER tuning. A well handling car can go SOUTH in a big hurry.

it will effect many things, including ride height. With 4 degrees castor change, you may not even have ride height to measure.

[Ed Womer]

Hey everyone please go back and read my response, I inadvertently said camber where I meant castor. Thanks to Chris Z for sending me a private message letting me know! I am going to blame auto correct, I wish.

If you have 9 degrees, in my opinion that is way to much. Steve did mention that changing it might change other things and he is correct. At least you will need to check toe after shimming the top beam to reduce the castor. In a moment of what was I thinking, I have, lent or rented my car out and would always add a 1/4" shim under the lower tube to give a little castor and ended up leaving it there. That would give a little self centering but I would still have the light steering that I prefer.

As a note my preference is towards over steer, so a heavy feel is definitely not something I want.

Ed

[Hardingfv32]

1) This car might have been fast but it certainly was no faster than other topline FV's.

2) FV is over five decades old, if a high caster number was useful we would all have settled on it many years ago.

3) Don't be afraid to undo a failed experiment. Steering force levels outweigh all the other possible small benefits that a high caster number might provide. So set the caster to a normal figure and get the car setup for it. Not that big a deal.

Brian

[Gary Slahor]

Good suggestions.... and thanks to all who responded.
I certainly can start with a smaller caster change and see how it goes. I was just going to use the recommended 5-6 degrees as a starting point.... but I can certainly go from 9 to 7 degrees to start.
I will re-check other alignments as well.
I have noticed in the FB that reasonably small changes in caster (say 2 deg) had minimal effect on the overall handling of the car, but as you say, the FV may be a different animal.
I will also consider steering wheel changes. The car has a 9" wheel now, and I do have a 10" wheel on the shelf, that "might" fit. If not, maybe I can space the existing wheel closer to my chest to reduce arm fatigue.