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VWporscheGT3 Fri Oct 23, 2020 9:13 am

Hi Guys,
Because the whole lot of us like to play with VW's , and not all of us has access to do such awesome things as the shop car build thread (911/914 front suspension) I wanted to start a thread about tuning the front suspension for handling.

Ground rules,

1.) yes we all know this isnt a Porsche, it is not a 911, nor is it a 356. So do yourself a favor and please refrain from being a troll and asking "why" or say something stupid like "go buy a Porsche"

2.) we are talking about modifying the Type 3 front beam for handling. we are not talking about buying a Type 1 beam and making that work.

3.) if you have ideas or theories or pictures of beams cut up so we can understand the insides of the beam , please feel free to add.


Remember that just about any car out there back in the day was used for racing or performance in some way. people modify their cars to suit their tastes. hell why would someone slam a mid 60's ford truck to the ground and then turn it into a autocross toy.... that's what they wanted to do so who am I to criticize it .

now to the core of what I am after , and maybe others. Handling. when I look at the front of my car the wheels almost seem to have positive camber in fact I think i remember seeing something in the bentley about how that is its natural state.
if i remember correctly also the ball joints are eccentric and you can dial in a bit of negative camber there...please correct me if I am wrong. I can only imagine this would bring a couple points which would lead me to another option which would be shimming the torsion bars to kick out the lower arms.
this of course could lead to issues with sealing the beam where the arm meets the beam. This also has me concerned about spline engagement , how deep they go.. etc


the whole reason this comes up , is i like to drive backroads a little aggressively , but i would also like to look at autocrossing in the future. My fasty is what i lovingly refer to as my POORSCHE, and i would like to set him up to be an aggressively cornering machine.
I've done a few searches and haven't come across anyone doing like what im trying to do with the factory beam, if you have please point me to it.

this thread isnt limited to camber/castor and toe.. lets talk Brakes , lets talk spindles, etc...

and If nothing comes of this thread then I'll understand that its not a subject many care about

grenadeAcorn Fri Oct 23, 2020 9:23 am

Watching, please continue :D

Mike Fisher Fri Oct 23, 2020 11:48 am

Down 2 & 1 inner notches front & rear makes a world of difference in the handling/cornering/braking w/185 & 205 tires on 5.5" 2.0 liter 914 wheels.

Nate M. Fri Oct 23, 2020 1:14 pm

No need to reinvent the wheel to push your car to the limits and have fun.

If I was to modify a factory type3 beam I would remove the torsion bars front/rear and look for a nice set of fully adjustable coil-overs. With this type of set-up, you have near-infinite choice on spring rates and you adjust the valving to suit your driving. You will want to take your car by a closed weigh station and record the weight over each axle so you know how the weight is distributed front to back before consulting on what # rate springs to buy. Then you can jump down the rabbit-hole that is suspension tuning. :wink:

Couple that with a 3/4" sway bar front and rear and your suspension should be pretty solid. Other than that, its just bushings (urethane) to make everything is more solid.

Type3s have pretty good brakes in the '67-on cars. Rears are where you can improve things with discs.

Tires are really important. I would consider buying a spare set of wheels and tires specifically for warm weather/performance driving. When looking for tires, always check the "tread wear rating" and look for tires with a 200 or lower rating. Most will be rated as "Extreme Summer" tires. I can personally recommend Hankook RS4s. I'm running RS3s on my car and will be getting the RS4s in my next tire purchase. I moonlight on a spec Miata endurance racing team and we run the RS4s. We've been very happy with their performance on the track and their longevity. We can easily run an entire race weekend (typically 16 hours at race pace over 2 days) on ONE (1) set!!!! They are also very affordable. On my car, I run the summer wheels/tires from April to October. Then the all seasons go on. Yes, I'm an all-season flogger of the dub!! :twisted:

vwfye Fri Oct 23, 2020 1:16 pm

I have found that a 175/55r15 allows for a bigger contact patch than stock, but low sidewall helps with cornering. I also run bilstein stock length shocks with 3 outer splines down. Remove the bumpstops and the car has suspension travel, tracks like a slot car and gives the driver feedback.

Negative is the speedo is way off, but you learn to adapt.

VWporscheGT3 Fri Oct 23, 2020 1:28 pm

the two inner that I am down right now have made a world of difference so far. thank you for that addition. :D

I noticed last weekend when I was threading a little road in one tight turn in particular , that when I got on it at the apex that the front end understeer'd a bit I had to let off a bit and the front came around, I think this is maybe why I'm focusing on camber. I think if the wheels geometry on the outside cornering wheel would have had a little more I could have pulled out of that corner a little harder.
the beam im running came out of a 68 square i had so the sway bar thickness and torsions should be thicker from what i recall, handle a little more load... i would love to see what it would take to have new heavier sway bars made. i just dont know where to begin..
this weekend i'll try to grab the fastbacks original beam and pull it apart to take some pictures to really break down what is going on in there .



Im am running 185/65/15's up front and my speedo is 6mph too fast. but with that its a huge sticky different compared to the 165's the car originally ran .
Nate , I agree with your thoughts on coil overs. the thing i keep hearing about is snapping off shock mounts on the arm..which is what keeps me from doing anything with that, i would think custom arms would need to be built for proper strength .

more rambling than important info on my end, but please anyone feel free to add there 2 cents

W1K1 Fri Oct 23, 2020 3:02 pm

what should we be running for front end alignment numbers?

i swapped to 17's with sticky tires last year, but it doesn't feel the same as the widened stock 15" wheels I had on it. I had the alignment checked this spring.

Nate M. Fri Oct 23, 2020 5:20 pm

VWporscheGT3 wrote:
I noticed last weekend when I was threading a little road in one tight turn in particular , that when I got on it at the apex that the front end understeer'd a bit I had to let off a bit and the front came around, I think this is maybe why I'm focusing on camber. I think if the wheels geometry on the outside cornering wheel would have had a little more I could have pulled out of that corner a little harder.

This is pretty typical behavior on a rear-engined German car. Its all about managing weight transfer while trying to not shock the tires. The front-end is light with the motor in the back so when you roll on the gas it understeers. Modulating the throttle will transfer some weight forward and get the car to bite again. More camber can help, but the weight transfer is what you are fighting. I always do performance driving with a near full tank of gas (believe it or not, it makes a huge difference). With a stock beam you will be pretty limited on your camber unless someone has come up with a solution already.

VWporscheGT3 wrote: Nate , I agree with your thoughts on coil overs. the thing i keep hearing about is snapping off shock mounts on the arm..which is what keeps me from doing anything with that, i would think custom arms would need to be built for proper strength.

Yeah, this is why working within the confines of stock can be a challenge.

Qldelsie Fri Oct 23, 2020 5:50 pm

Not specifically VW or Type 3 related, but a couple of "suspension improvement" observations from an old man who has raced and Hill Climbed both Formula Fords and Lotus +++ for 20 or 30 years........
1) One is always chasing the optimum suspension set up. What I found is that for every change you make, there will usually be a negative as well as a positive reaction. For example, with changed settings, the car may handle better on a dirt road now, but it will have become worse on the black top. Or it may have less oversteer in the dirt, but lose straight line stability on the black top. 100's of examples of this. If there wasn't a down side to a change, then anyone could do it because there would be a set of hard and fast rules to follow, and we wouldn't be having this conversation. In real life, it is always a play-off. You have to decide what you want, and whether or not you are also prepared to accept the downside that possibly comes with that change.
Remember that manufacturers always have to compromise in their road car set ups, in order to make them "safer" for the average Joe Blow. Even Lotus. You can make it better on track, but then it is terrible for road touring, etc.
2) Making changes to suspension (like changing from torsion bar to coil overs) needs a lot of thought and engineering. On the Peking to Paris rally last year, mostly on rough dirt roads across China, Mongolia and Russia, on our 1954 Austin Healey we decided to keep our original lever arm dampers, but to beef up both them and their mounts. After all, while they have their limitations, the car was designed and built to accomodate them. To many people's amazement (including my own !), they survived and worked well the whole time. A number of other competitors in various cars chose to change their older style suspension, for example to coil overs, and then found they broke off and punched through their mounts and even bodywork on the rough roads. "I do not understand - they are the best dampers" they always said, not realising that by moving the impact point for the suspension to a new position, they had totally moved the stress points for them too, and the new positions weren't designed to accept those stresses, while also creating new stress positions. Needless to say,they were out of the rally.

Can our Type 3 suspension be changed / improved ? Absolutely - Technology and knowledge have improved exponentially in the last 50+ years. But when you make changes, understand what the effect of those changes will be before the front suspension collapses when you are flat out on opposite lock on a corner on a dirt road somewhere !
My suggestion would be to play with something simple like Toe settings first, from way In to way Out, and several points in between. Make changes, document them, then drive a set route and see what happens, and document it. Repeat........ You will be surprised at how much even that can change your car's characteritics (and note that I said "change", not "improve" :lol: )
Just my 2c.
G

Nate M. Fri Oct 23, 2020 5:55 pm

W1K1 wrote: what should we be running for front end alignment numbers?

i swapped to 17's with sticky tires last year, but it doesn't feel the same as the widened stock 15" wheels I had on it. I had the alignment checked this spring.

I run two basic front set-ups. One for street and one for the track. On the street I run around 1.5 neg. camber and set toe between 1/16-1/8" toe-IN. Toe-in gives the steering a nice light feel which is great for street driving.

On the track, typically I'll run 2.5-3.5 neg camber and I set the toe around 1/8"-3/16" toe-OUT. The added camber allows for more tire deflection when running lower pressures. Toeing the car out makes that inside tire hook-in better in the corner and can help a bit with under-steer. You'll wear your tires and wheel bearings faster like this so there's a cost. But damn is it fun!!

Cptn. Calzone Fri Oct 23, 2020 6:10 pm

Mr Fischer please explain down 2 and 1 inner notches

djway3474 Fri Oct 23, 2020 7:59 pm

I have watched many a videos of Bugs running tracks around Europe and understeer/push is the common problem.
You can try a light tap of the brakes going into the turn to set the front but you can't really accelerate until near straight, even maintaining speed can be difficult and you must modulate as stated above.
Negative camber for sure. Has anyone ever tried spacing out the lower trailing arm, I have no idea if even possible.
Also remember what the left rear is doing in a righthand corner affects the right front. You can help the front or hurt it with what you have done in the rear.
Softer setup better for loose conditions, stiffer for high grip.
Toe out as stated above but remember the steering won't self correct as it does with toe in.
As to comparing with a 356 not really that much difference except they probably have a much lower roll center. You could probably add weight low in the pan and even in the spare tire area would improve roll characteristics and push.

eyetzr Sat Oct 24, 2020 2:46 pm

Cptn. Calzone wrote: Mr Fischer please explain down 2 and 1 inner notches

You can move the spline position on the control arm, as well as inside the beam. You reposition the torsion bar, then reposition the control arm.
2 out 1 in, or what ever you fancy.

Yabbadubbadoo Sat Oct 24, 2020 4:50 pm

Looking at my chassis just yesterday it occurred to me that front camber, when set at a neutral position, (zero ball joint offset adjustment) the car sits with a very noticeable positive camber. (Top of tyres pointing outward) Indicating to me that it might have been designed specifically for cross-ply tyres. It reminded me of the way my old FJ40 landcruiser would look on the front axle before I put shims on the swivel hub to remove positive camber for the radial tyres. Wondering if VW published wheel alignment settings for both cross-ply and radial tyres.

Also, is there enough adjustment in the offset ball joints to dial out some of that positive camber for better handling and wear characteristics using radial tyres?

Pushing lower control arm outward by somehow modifying the bearing positions by more than 1 or 2 mm would require some very difficult metal work outside the expertise of the average punter. This would be a very deep rabbit hole to wander down.

Bobnotch Sun Oct 25, 2020 10:48 am

eyetzr wrote: Cptn. Calzone wrote: Mr Fischer please explain down 2 and 1 inner notches

You can move the spline position on the control arm, as well as inside the beam. You reposition the torsion bar, then reposition the control arm.
2 out 1 in, or what ever you fancy.

Yup, out or outer is moving just the lower torsion arm on the bar. The inner is moving the other end of the bar (or inner end), as most times the lower torsion arm has rusted to the bar and won't come off it. I've moved both ends before, as sometimes 1 end will be off more than the other (the PO tried to readjust the front end). :roll:

VWporscheGT3 Mon Oct 26, 2020 7:53 am

Thank you all for your contributions. I didn't get a chance to get out to the garage on Saturday. There was just too much going on. and then sunday hit and it was too flipping cold and I am a wuss with no heater for his garage.
I can definitely see the balance between tire wear and added grip is going to be something to take into consideration and I believe I will have to find a balance for myself. Hopefully this next weekend I can make it out to the garage an di-sect the original fastback front end and take some good pictures.
I believe we have some folks within this forum that have a wealth of information to share... we just have to ask the right questions

Cptn. Calzone Mon Oct 26, 2020 9:10 pm

S my cars being painted I am taking care of all of the other issues to assemble one of them being the shifter what is everyone's opinion on chainGENE BERG versus CSP vs stock

W1K1 Tue Oct 27, 2020 7:42 am

Quote: shifter what is everyone's opinion on chainGENE BERG versus CSP vs stock

berg, CSP, vintage speed, all solid choices, stock is pretty sloppy at 50 years old

vwfye Tue Oct 27, 2020 7:52 am

Hurst Indy 500 shifter!!!!!!!

Bobnotch Tue Oct 27, 2020 8:11 am

I'm really old school, in that I use a "quick shift kit" and a stock shifter. Been in the car for the last 20 years without an issue.



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