Brock B Coupe build

Ray I'm pretty sure he is in bed, give him 8 hours! Lol

Part of the front shock tower bracing done.

Brock B posted:

Ray I'm pretty sure he is in bed, give him 8 hours! Lol

The dark side of the moon  

I've always been impressed by over building of the CMC/FF sub chssis.  I'm guessing a Coupe doesn't need the rear bracing like the Speedster? The side pieces are used to transfer heat to the front of the car.

Reply to Alan, 

Yes, we have full parts list with sourcing and part numbers. For overall general assembly, we usually send a copy if the FiberFab assembly guide From the SOC Resources library) for the builder to get the big picture.  Everyone does their build a bit different.

CHEERs, Chris

Kitman Motors

Brock:

You sure build your cars faster than SAS.

Wolfgang, a coupe may not need any rear bracing but mine is getting something back there!

Bob, I try not to mess around to much don't want the project add to kick in before its done. 😎

One floor half welded the other half fitted.

What gauge steel did you use Brock ? Is it stainless ?............Bruce

Bruce, its .060 so 12 hauge ish.  Its mild steel but it had what looked like a phoshate on it to keep it from flash rusting so quickly.

Fully welded in

The Kitman chassis is 62” wide

great work Brock

Impressive progress.

12 Ga. ! ! Wow ! That ought to stay in place !  Having a flat floor to work up from has to be a pleasure with no surprises ! Welding to it shouldn't produce any wir=erd warps either. I like what your doing...............Bruce

Thanks Ian! 

My chassis is 61.5! Not to bad for a guesstimate! 

Edsnova Thanks!

Bruce , Thanks! At the end of the day it is fiberglass so i want to make it as strong as i reasonably can.

Front firewall cut and welded in.....

More 12 Ga. ?  Your brake and clutch assy. will be sturdy !  Lookin good Brock !....Bruce

Wow, Dude! You're gong so fast I can feel the breeze up here in Oregon!

You might want to consider adding disconnects between the front beam shock towers and the cage you welded in. If you ever need to remove the front beam you will understand. I just Roll cage couplers on the parts I might have to take apart. Something like this 

https://www.summitracing.com/p...lLi5ggIaAqUJEALw_wcB

Michael,  Bruce Thanks!

DWP , thanks but removing the beam is the last thing on my mind. I want this car stiff, the beam will most likely be welded to the lower part as well. The rear torsion tubes are alreay welded to the chassis on the ends and will also be tied in with the cage at the top of the shock mounts.

 @Brock B- My apologies if this is already known territory, but before you weld the beam in place- do you know about the need for increased caster in the front suspension in these cars?

If stiffness and handling is what your after consider braces for the outer part of the beam. I have something similar to this on my “street Rail” and would do the same on a 356. It also what the off-roading guys use. Dave

https://www.mooreparts.com/emp...or-vw-baja-bug-pair/

ALB, i did not but after some reading they may have to go in...if they will now without cutting anything.

DWP They could be usefull.

Painted......and the ball joints are out, they were loads of fun!

Here's photo of the lower front beam supports that DWP referenced.  They are an easy add on to any Speedster or dune buggy.  Made by Empi but not much for them to screw up. Easy bolt on but may interfer with front bumper brackets. The second photo is of their upper ones which probably isn't as easy to install on a Speedster.

CSP has a version too --- but much more $$$ - $199 Euros (and higher quality).

A further note on caster- ball joint Beetles came with 2' 30" (+ or - 30") caster while Porsche Speedsters had 5'. VW front suspensions, when lowered by adjusters, Select a drop or cutting tubes the car will LOSE caster and it can become a bit of a handful even at legal highway speeds and downright dangerous as you go faster. I have personal experience with this, at one time having built a Cal Look bug that was work to keep straight at 60 mph and was almost uncontrollable at 100 mph. I knew nothing about caster 35-40 years ago.

For a car to be safe at higher speeds there needs to be more caster than stock. Most people here that have addressed this run 5-6' caster. Normally this is accomplished with shims under the bottom beam. Gene Berg Ent. caster wedges http://www.geneberg.com/cat.php?cPath=12_384_2917 are 5.9 mm (.236") thick and will add 2.36'. If you're welding the front beam in don't forget to take this into account.

Hope this helps. Al

x2 on 5-6 degrees positive caster. If I were doing what you're doing I'd buy a set of caster shims (which are aluminum), duplicate them in steel, mock the beam up with them, measure for square and weld away.

Your car is going to be pretty heavy. Gravity is a good thing, but if you're expecting to drive your car over 60 then shims are REQUIRED! You'll need two on each side.

So let me get this  right , each wedge is roughly 1/4" thick and  adds roughly 2.5 deg of caster.

Jim says i need 2 PER SIDE, that ls 5 deg...is that correct? 

So what will the total caster be AFTER the wedges are added?

The car will only need 2 sets of shims if it's lowered a fair bit with only adjusters or cutting the beam. Using 2 1/2" drop spindles doesn't change the caster, so even if you lower the front a little more with the beam then 1 set of shims is usually enough to get it safe at higher speeds. Usually this is checked when the car is complete and it's getting aligned, so if you're intent on welding the beam in place, be sure of where you are before committing.

The issues with drop spindles- they add 1/2-5/8" track each side, which some people don't like. There seems to be enough fender clearance in most instances. There are also some cast aluminum 15" wheels which just touch the bottom ball joint area. IIrc some Rivieras have this problem. I have heard of guys managing to clearance the area in question to fit. 

Yoda out (for now, but know you can't get rid of me!)

ALB Thanks but do you mean 2 packs (4 shims) or just  1 pack  (2 shims) ? 

I am going to use drop spindles, no going to mess with the bars on the front unless i have to.

Don't weld it in until your finished and after you have the correct geometry up there. The welding can be done with the fuel tank out and the wheels off later.

The 12 ga floor should be a nice small improvement to your CG too !..........Bruce

Brock:  All of the shim sets I've seen are about 1/8" thick, which gives you 2-1/2º to 3º of increase.  How many you use depends on where they get your caster to after install.  On my last alignment, adding a second shim on one side wasn't quite enough but a third shim was too much so we cut a segment out of a piece of electrical conduit (about 3/16" wall) and there we were.

Most set-ups run two per side (or one 1/4" I guess) behind the lower torsion tube to get you to about 5º - 7º of caster.  If you have a stock of thin-wall steel tubing (pipe) with the same ID as the OD of your torsion tube, you could make a set yourself - there's not much to them.

On a lowered car, they will greatly reduce bump steer and wandering at turnpike speeds.

Bruce, i hope the car feels tight and planted when done so yeah I'm thinking a little extra weight down low wont hurt.

Gordon, ok the ones i saw a pic of looked thicker than that , the top part is already welded so i will have to see how much the bottom will move.

Big-A$$ Pry-Bar, Brock.

All you need is 1/8" to slip the shim in there.

Lol yeah i have a couple about pinch bars 4.5ft long should do it!

Brock B posted:

ALB Thanks but do you mean 2 packs (4 shims) or just  1 pack  (2 shims) ? 

I am going to use drop spindles, no going to mess with the bars on the front unless i have to.

With drop spindles most people only need 1 shim on each side of the bottom tube.

If you need 2 shims per side - be sure to purchase the longer bolts for the bottom as the OEM ones won't be long enough.

Drop spindles would change caster because the front of the car drops relative to the back.  The change in angle would offset some of the existing caster.

A piece of a pipe wouldn't be the same as a shim.  A pipe has a different radius inside and out.  A piece of pipe would have a uniform thickness.  A shim has the same radius on both sides - it matches the tube and tapers toward the edges.

Ok to much conflicting info here, 1 shim,  2 shims, .....

The ones i saw on youtube last night were atleast 3/16 maybe 1/4 thick not 1/8. 

Guess i will just have to wait till it gets aligned to figure it out.