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Hey guys,

Long time lurker but finally bit the bullet and registered. There is so much good info in this forum and there appears to be ALOT of guys that have gone down the path im headed. Really looking for any advice that pertains to my setup. Trying to be as thorough as possible so there is quite a bit of info below...

I've been building my car off/on for the last ~5 years or so and i'm finally ready to throw it on a track. I've been trying to tune it on the road, there is a nice super short curvy road that is about 2 miles long ~ 3 mins from my house. The turns are all tight and its relatively smooth.

Im registered for an Auto X event this weekend and im trying to fine tune my suspension. Car is 90% track, at least that is the goal. It is street legal and will be driven on the street but I will NOT sacrifice performance for comfort. Car is gutted, no interior and lexan windows all around. Motor is solid mounted and the car is fully caged.

Front end:
- Puma stock width adjustable beam (ball joint)
- Drop spindles
- Empi Camber eccentrics
- Sway bar 3/4"
- Koni Adjustable shocks
- Double caster shim under beam
- 205/50/15 Yokohama Advan A052

Rear end:
- 27mm long bars
- Koni Adjustable shocks
- Empi adjustable spring plates (these are currently installed with no preload and I think the car is still to high in the rear)
- Sway bar 3/4"
- 225/50/15 Yokohama Advan A052

Most everything suspension wise has been replaced. The exceptions are the front upper/lower and rear trailing arms. In the rear all rubber bushings are now poly bushings. So far from my test drives i've done the following:

1. Loosened up the shocks up front. They are probably 1/4 turn in towards the stiff side.
2. Loosened up the shocks out back. They are about 1/2-3/4 turns in towards the stiff side.
3. Adjusted the front camber (I never did this after all the new parts). Right now its set to -.75 degree. I have not been back out on the road to test this change. Previously it was +1.5 on the driver and -1.5 on the passenger. I couldn't get any less than -.75 on the driver side (range was -.75 to + 4). Passenger side was the opposite where the range was like -4 to + 1. Settled on the best I could get it.

Still to do:
1. Check/adjust toe up front after the camber changes (I have a tool coming Thursday)
2. Check/adjust toe in the rear. I've never done it and im sure its off.
3. Play with the ride height. Using the top of the running board as a reference point. The FL sits at 7.5" and the FR 8" (not sure how to fix this). The rear is 9".

ALl in all the car handles pretty good. I just know there is potential for more. Just need tweak and fine tune to get it running optimal. Attached a few pics for reference. Any and all feedback is appreciated.

Welcome to the STF! Mean looking machine you have there! Whats in it for the power plant?

V8Nate wrote: ↑Wed Aug 12, 2020 2:47 am Welcome to the STF! Mean looking machine you have there! Whats in it for the power plant?

I've currently got my "backup" motor in it. Nothing to special. Heads are to big and the cam is to small but it gets the job done for now. Currently waiting to get my IDAs back from Jack over at Jaycee which will pair to my primary race motor. Until then, I'll keep running the backup motor which is 78.4x94 with an FK8. Dual 44IDFs 1 5/8 exhaust. Heads are thought to be some old school SCS heads with 44x37 valves. IIRC I set the CR to right about 9:1.

The motor planned for the car (I have all the parts, did initial mock up. Its currently torn back down. I need to clean everything and re-assemble once i get my carbs back):
- 78.4x92 (forged pistons)
- Stock I-beam rods, clearance/balanced
- FK47 paired with Thorsten Pieper Tool Steel 56g Lifters
- Steve Tims Weekend Warrior Heads (42x37)
- CB Crank Trigger (this is currently on the backup motor, so far im happy with it)
- A1 1-3/4" header. Ceramic coated. Paired with a magnaflow muffler
- 48IDA being restored by Jack
- CR target is 10.25:1

Trans is a 6-rib bus box built by KCR. Gearing is TIGHT. Unfortunately all I know is its got a 4.57 r/p. I picked it up used and had KCR rebuild it for me to ensure I would have no issues. I asked him to give me the ratios while he had it open but he forgot . Should be a great box for auto x and maybe some 1/8 mile drags though.

I think you are on a very good path to handle well. It sounds like something is slightly bent in the front suspension, the beam or a front trailing arm. Anyway, there are jigs to check the the trailing arms. Once you know what you have you can get the top arms bent a little in a press to give more neg camber, at least 2 deg neg but up to 4 can be good.
broadly work on 3 things, keep the car as flat as possible using swaybars etc. get a tyre temp gauge so you can see how much neg camber you can run (even temp on the inner and outer edge of the tyre) and what is the ideal pressure (same temp in the middle as the edges). Check the rear too. Ride height determines the rear camber so you can work on that too. I like a little toe in front and rear but others do differently.
After getting these things right you may need to change sway bars to adjust under/oversteer.
There is some very good info here from Greg Ward who races Hillclimb but many of the same settings may work for you
https://www.aircooled.net/vw-handling-s ... on-tuning/
good luck

Ian Godfrey wrote: ↑Wed Aug 12, 2020 9:35 pm It sounds like something is slightly bent in the front suspension, the beam or a front trailing arm.

This was my thought aswell. The beam is brand new, I had Kaddie Shack order the beam and assemble/install the spring packs. I remember when I pulled my old one off I could not for the life of me get one of the arms off so I ended up buying a used one. Was either swap meet or ebay. Thats probably the culprit. I'll have to go dig out my old beam and see which arm is still attached and that will tell me which one I replaced.

Ian Godfrey wrote: ↑Wed Aug 12, 2020 9:35 pm Anyway, there are jigs to check the the trailing arms. Once you know what you have you can get the top arms bent a little in a press to give more neg camber, at least 2 deg neg but up to 4 can be good.

What is typical range of adjustment? I've read numerous posts of guys saying they can only get -1 and others were guys are saying they can get -4 and -5. This will also help me in figuring out which side of mine may already be bent.

Ian Godfrey wrote: ↑Wed Aug 12, 2020 9:35 pm Check the rear too. Ride height determines the rear camber so you can work on that too. I like a little toe in front and rear but others do differently.
After getting these things right you may need to change sway bars to adjust under/oversteer.
There is some very good info here from Greg Ward who races Hillclimb but many of the same settings may work for you
https://www.aircooled.net/vw-handling-s ... on-tuning/

Yeah I actually played with this last night and only AFTER lowering it further (My plate went from about 9 degree to 7.5 degree, equal on both sides) my driver side camber is maybe -1.4 (my gauge is a bubble, so its hard to report on exact numbers) but my passenger side went all the way to -4. I'm planning to lossen up the bolts and maybe trying holding the rear of the TA up then tighten the bolts down. Hoping this will even it out

The info from Greg Ward i've read probably 3 times now. Very good info there.

With offset camber eccentrics I could get -2 at the front with stock arms, so I got -3 pressed into the upper arms so I can go from about -1 to -5 using the eccentrics.
Make sure the hole in the eccentrics is to the rear of the car to maximise the caster.
another thing to note, is as you get more neg camber the front tyre can touch the shock on turning, but you can file the hole in the top shock mount to move it inboard.
Yes you will get quite a bit of camber change by adjusting the rear trailing arm in the slots in the spring plate. I always found it difficult to measure and hold it still while I tightened it up, I ended up using a G clamp on the spring plate and arm, then tightened.
Not sure what you have, but the single spring plates are easier to adjust than the double spring plates.
good luck

We have three regional autocross championships with our '70 Ghia. Drop the front and rear ride height two inches, and having the rear one half inch lower than the front is not a bad thing. Roll stiffness with 19mm front and rear bars is substantial. When you get fast, you may find the car wants to skate sideways rather than bodyroll a bit and dig in. Your driving style matters here.

You want instant throttle response. IDA's might be too much. We actually got our best throttle with (Kadron) Solexes (44mm throttle bodies, match ported manifolds, 34mm vents. Webers can outrun Solexes on a long road course, but for autocross, you never get the full Weber advantage unless you choke it down below 40mm vents. Think 36mm.

And give the engine as much compression as you can afford. 9:1 minumum. To snap out of a quick chicane, 11:1.

Lighten the hell out of the car. Lexan windows sides and rear. Glass is heavy. Get an alumimum seat and good tight belts.

You can beat the ricegrinders.

I've had the best luck with my rear adjustable shocks on full stiff, and the fronts at 4-5 out of 20 for stiffness. I have bars front and rear and am running 195/50F and 205/50R Toyo R888 tires. You'll know when the front is too stiff by it skipping/bouncing thru the corners. A touch softer and it'll stop doing that.

ps2375 wrote: ↑Mon Aug 24, 2020 7:37 am I've had the best luck with my rear adjustable shocks on full stiff, and the fronts at 4-5 out of 20 for stiffness. I have bars front and rear and am running 195/50F and 205/50R Toyo R888 tires. You'll know when the front is too stiff by it skipping/bouncing thru the corners. A touch softer and it'll stop doing that.

I have a question about sways. I have the big Topline bars on my '73 Super and must admit, I don't have much to complain about. It carves around cones far better than my GTI I ran for almost a decade. On my '74, I'm thinking about a factory front bar(with urethane bushings) and a 15mm Porsche 944 rear bar. I'm only considering this because my inside front wheel lifts on tight turns on the '73. On my old, stiffly sprung GTI, it lifted the inside rear wheel, but that didn't matter because the wheels are just coming along for the ride, but on the Super, it effects the steering control. I'm hypothesizing the smaller sways will be beneficial. Any thoughts?

H2OSB

I’ve got the mounts in place for the 15mm rear 944 bar, with the 30% stiffer 944 torsion bars.
Up front I have a rare 16mm sway bar (standard, not strut). Hoping to add coil over springs in the 40-50 ft/lb range to get a spring frequency to match with the rear.

Will find out how that works when it’s back on the road, probably next spring.

Is your 74 a super or a beam car? If it has a beam front end I think getting the car flat to control camber is more important than stopping the wheel lifting. Tyre temps and the 'balance' of the car should let you know. I don't have experience with a super so I can't comment, other than to say there is another variable with the added front camber changing with lowering and spring compression during turning and braking, so the answer may be different to a beam car.

The rear bar keeps the front tires on the ground. Don't soften up your front just yet, Add more rear.

Remember, the sway bars act in an X pattern. Left rear tire depresses right front tire, etc. Super's need at least a 19mm rear bar.

If this is not a beam car then ignore this post.

Check the front beam for being level or pushed back on one side or the other. Jack the front end up and put floor jacks under, not the beam but the side of the pan where the firewall is. Next measure the beam on both sides to see if it is parallel to a parallel floor then measure the beam to the firewall on both sides. If everything is OK then there are a couple things some of us off-roaders often use.

Assuming this is allowed where you are running (http://v1.empius.com/vwcatalogsite/vwca ... 8/443.html): the two lower parts, #3842 and #3843 are end supports for the beam to keep it from being damaged in rough use and helps support the beam's mounting piece on the pan.

The lower tube connects to the beam then to the slotted body to pan holes at the firewall using the same or a bit longer bolts. The upper tube connects to the upper beam then it is bolted to the fire wall.

Another thing to think about (maybe) are beam adjusters. They allow you to not only raise or lower the front of the car but by using only the top one you can preload or reduce the torsional application (preload) of the upper tube.

I'm doing the latter on my off-road beam to soften up the front end as there is almost no weight on it but still keeping if from bottoming out when needed. We also don't run sway bars so give this idea both good and bad thoughts.

So many things that unexpected things can do.

Lee

Oh man, some great responses in here. Sorry for the delay, I didn't get a notification (my fault).

FJCamper wrote: ↑Sun Aug 23, 2020 4:29 pm We have three regional autocross championships with our '70 Ghia. Drop the front and rear ride height two inches, and having the rear one half inch lower than the front is not a bad thing. Roll stiffness with 19mm front and rear bars is substantial. When you get fast, you may find the car wants to skate sideways rather than bodyroll a bit and dig in. Your driving style matters here.

You want instant throttle response. IDA's might be too much. We actually got our best throttle with (Kadron) Solexes (44mm throttle bodies, match ported manifolds, 34mm vents. Webers can outrun Solexes on a long road course, but for autocross, you never get the full Weber advantage unless you choke it down below 40mm vents. Think 36mm.

And give the engine as much compression as you can afford. 9:1 minumum. To snap out of a quick chicane, 11:1.

Lighten the hell out of the car. Lexan windows sides and rear. Glass is heavy. Get an alumimum seat and good tight belts.

You can beat the ricegrinders.

ok, first off let me say i've spent the last few days just reading your posts. EXTREMELY good info. When you say drop the front and rear height 2"
are you referring to the stock height or going based on the pic I sent? I.E. are you recommending it drop an additional 2"? I found the front sway bar was causing some binding issues. After getting that sorted the front actually dropped down a smidge.

Throttle response right now is fantastic. Im also (for now) just running my backup motor. 9.1:1 compression and a 9lb flywheel (44 IDF 36 vents). IIRC my race motor will be 10.2:1 (i'd have to look at my notes to confirm exact). I've already been having some second thoughts on the IDA. Once built i'll run it and adjust as necessary. What you are saying makes sense though.

In regards to lightening it, i've already got lexan windows all around with a Kirky aluminum seat. Interior is fully gutted.

Took the car out for another event last weekend. Broke after 2 runs. Didn't do too bad though. I ended up putting in 27mm short bars in the rear and that helped substantially (used to have 27mm long bars). Dealing with crank case pressure issues now. Keep sucking in the valve cover gaskets. I have both covers and the alt stand vented to a breather box. Not enough apparently. I've read your post using the Krank Vent like 4 times. Really good info. Right now im leaning towards going to a dry sump setup and re-working the breather setup. Trying to decide between the AC 2 stage and the CB pump right now.

ps2375 wrote: ↑Mon Aug 24, 2020 7:37 am I've had the best luck with my rear adjustable shocks on full stiff, and the fronts at 4-5 out of 20 for stiffness. I have bars front and rear and am running 195/50F and 205/50R Toyo R888 tires. You'll know when the front is too stiff by it skipping/bouncing thru the corners. A touch softer and it'll stop doing that.

Mine is the opposite right now. Shocks are on the loose side. I've been debating stiffening them. With a new setup that I have very little seat time figuring it out its a bit of trial and error.

Ol'fogasaurus wrote: ↑Mon Aug 24, 2020 7:47 pm If this is not a beam car then ignore this post.

Check the front beam for being level or pushed back on one side or the other. Jack the front end up and put floor jacks under, not the beam but the side of the pan where the firewall is. Next measure the beam on both sides to see if it is parallel to a parallel floor then measure the beam to the firewall on both sides. If everything is OK then there are a couple things some of us off-roaders often use.

Assuming this is allowed where you are running (http://v1.empius.com/vwcatalogsite/vwca ... 8/443.html): the two lower parts, #3842 and #3843 are end supports for the beam to keep it from being damaged in rough use and helps support the beam's mounting piece on the pan.

The lower tube connects to the beam then to the slotted body to pan holes at the firewall using the same or a bit longer bolts. The upper tube connects to the upper beam then it is bolted to the fire wall.

Another thing to think about (maybe) are beam adjusters. They allow you to not only raise or lower the front of the car but by using only the top one you can preload or reduce the torsional application (preload) of the upper tube.

I'm doing the latter on my off-road beam to soften up the front end as there is almost no weight on it but still keeping if from bottoming out when needed. We also don't run sway bars so give this idea both good and bad thoughts.

So many things that unexpected things can do.

Lee

Interesting idea with the support braces. My beam has already got adjusters in it.

As you go around the cones the body wants to tip mainly because of the high weight of the top of the car and the people in the car. The beam mount is not as supported by the body as well as the pan is to the beam mount can twist some. The supports go from the beam to the pan (the lower one) and from the beam to the front firewall the (then hopefully to the cage) in the front. Also hitting anything say a pot hole when on the street the additional support is there.

Off-roaders are more prone to mount them a lot.

Lee