Time attack beetle

[Wally]

Despite the mishap with the rear main seal (sounds kinda familiar), nice progress on the reinstallation of battery and DS tank.
I think it only got better

[Humble]

More trials and tribulations but going in the right direction again.

Had a 3 day weekend off work so I spent all three days working on the bug. Friday I spent tearing the torsion bars out and installing the new coilover setup. It took a little more work than I anticipated, the lower 1/2" adapter standoffs were a real pain to get into the trailing arm but they're torqued to spec. Right now I still have the trailing arm bushings in place and I'll switch to a uniball setup later. On the upper mounts and cup brace I had to widen the holes out to 1/2" for the new upper bolts. The coilovers are QA1 units with 7" springs but really need 9" or 10" springs, and they are 16 way adjustable in rebound only.



With the suspension done on friday I could get down to the motor and tranny on saturday. I had some help and we were able to get everything out of the car pretty quick.



A closer shot of the new tranny from rancho. Single side cover late IRS case, super diff, albins chomoly gears, electron beam welded gear hubs, pro synchro rings, and steel shift forks. It's got a 2.90, 1.86, 1.28, .90 with a 3.88 R&P good for over 160mph at 8000rpm if I have enough HP to push the car through the air.



Got the tranny in, replaced the rear main seal with a new double rear main setup a lot of racers are switching to. It's two seals as thick as the normal single rear main seal. Buttoned everything back up, got the motor in and fired it up. Once it was hot it had more leaks than before we took it out. I was ready to cry because at that point the sun was setting and we had been working on the car all day. But after closer inspection I noticed it was an oil gally plug (AN allen head plug) that was leaking, and sure enough it was loose. So come sunday motor came out yet again, tightened up the galley plugs front and rear put it all back together and no more leaks, almost. I still have small drips coming from the valve covers but the rest of the block is finally dry.

There's only a couple of things left on the short list before dyno time and it's nothing major. Shift rod bushing, better throttle return springs and trim the fender and rear apron to clear the turbo.











In the course of the weekend I broke my big torque wrench, broke a pressure plate bolt off into the flywheel and had to drill it out, got covered in more gas, oil and moly grease than I could scrub out, and collected more scrapes and scratches than a five year old with a new bike, but I think the end result was worth it.

[Wally]

It was pleasure and great deal of recognision (sp?) to read your last report.
The stupid leakages from simple things that would have been so easy to adress the time you were in there before up to the cratches and brouses (sp?)
Good work! Just be carefull with that spoiler thing. It looks like it will resonate and come off under real speed...

[kuleinc]

I love your updates, wicked great progress! I'm not a big fan of fenders that wide, they look a bit goofy to me in the from the front pics, but those wheels an tires are all business.

Also, could you BE stuffing anymore stuff into your engine bay?

[Sandeep]

I see your QA1's are mounted upside down ... do you have any issues with that ? Are they recommended to be mounted upside down as an option ?

Great updates !

Sandeep

[Simon]

Originally Posted by Humble

It took a little more work than I anticipated, the lower 1/2" adapter standoffs were a real pain to get into the trailing arm but they're torqued to spec. Right now I still have the trailing arm bushings in place and I'll switch to a uniball setup later. On the upper mounts and cup brace I had to widen the holes out to 1/2" for the new upper bolts. The coilovers are QA1 units with 7" springs but really need 9" or 10" springs, and they are 16 way adjustable in rebound only.

Looks nice!

The standoffs are racers edge parts right?
How much clearance do you have between the springs and the trailing arms?
The springs are 60mm ID springs?

The 7 inch (177.8mm) spring doesn't give enough travel?

[Humble]

I think I'll keep a close eye on the wing with a rear facing camera for the first few runs and watch for deflection. If it's too bad I'll pull it off and wrap it in carbon which should stiffen it up. I also want to change the end plates and make them longer vertically which should make the wing more effective at speed.

The lower coilover spacers are the racers edge pieces, expensive but worth it. There's about a 1/4" (8-10mm) of clearance on the trailing arm and I ran It from full droop to full compression and the spring never gets close enough to worry about.

The QA1 can be run inverted without issue according to the tech I spoke to however the adjustment knobs are a bit harder to reach behind the big wheels. I thought they were only rebound adjustable like most other single adjustable shocks but apparently they adjust rebound and compression together. The model # is DR4855B for the promastar single adjustables.

The springs are 2.5" (about 65mm) in diameter, and set for maximum ride height right now, which gives me no room to increase spring pressure at a rear corner if I needed. Right now I've got 2" of droop and 2" of compression which is about perfect, but I'll probably be increasing the spring rates quite a bit. I'll probably switch to a 9" spring for more tuning room and move up to a 450# spring for the rear and a 350# spring for the front for a new race setup.

I found a quick (rough) spring calculation from a rally group to get spring rates. First, find your corner weights, for me it's 435# in front and 610# in rear (just the heavy side right now). Now multiply that by the max g-force the car will see, typically 2.5g's in road racing, so that's 1088# and 1525#. The bug isn't so light at 2.5g's Now take that heavy number and divide it by your suspension travel, in my case 4" front and rear so that's now 272#/in. in front and 381#/in. in the rear that are needed to take up that kind of weight in the corners. Not done yet though, that gives you spring rate but you need to find the effective wheel rate to make this work right. For 944's it's 90% in front and 60% in rear. What that means is if you compress the rear trailing arm 1" the spring will only compress .6" so you need a stiffer spring to make up the difference. So you multiply your front spring rate by 1.1 and the rear spring rate by 1.4 which gives you 299#/in. in front and 533#/in. in rear.

All this calculation is based on my last weigh in but none of these values are current. Since I last weighed in I moved the gas tank, gutted the car, moved the battery, and added more weight to the rear with the oil system and turbo kit. I'll re weigh the car once everything is sorted and order new springs then.

[Sandeep]

Thanks for the confirmation on the upside down mounting of the QA1 coilover. I have the HAL-DR5855P model and found out that they fit a stock steel trailing arm much better upside down, with no rubbing anywhere of the spring and adjusting mechanism. The adjusting knob is, of course, at the top of the rear shock tower now.

Sandeep

[Humble]

Still sorting little problems with the car trying to work the bugs out. Took the maiden drive though, nothing special, but kind of frustrating. I hadn't quite set the shifter right and I left the wrench at home, so I couldn't get the car into 1st to climb our 7% grade driveway. I got it into first and up the hill eventually but it took a while.

A new item on the short list, a leaking MC. The plastic fitting on top is cracked and leaking so I need to find a new one. I also need to sort out the turn signals. Left side works fine but the right side makes all four corners blink. I'm on the fence about the pro synchro rings in the tranny. You really have to punch it into gear, even at low speeds, to shift otherwise it grinds. I need to see how they behave at full speed.

Finally got the fuel sender dialed in right, now full is full and empty is not full. While I was working on the tank, I checked the breather and I think I'm going to route it down out of the trunk areato reduce the underhood fumes.

Other than that I'm going to be scheduling dyno time on monday and well see what this baby can really do!

[Wally]

Originally Posted by Humble

Other than that I'm going to be scheduling dyno time on monday and well see what this baby can really do!

Cool, you feel the rings have settled already (by) then?

[Humble]

We're going to break the motor in on the dyno, change the oil, then go for a top tune on boost, then add water injection and timing. Aiming for 350+ but I'll be happy with anything more than 300.

[Humble]

Dyno day is set for next Wednesday the 27th! My predictions are 350hp and 310 lb/ft torque @ 20+ psi. Well see if any of that pans out or not. I took a little trip around our neighborhood yesterday trying to nail down a streetable tune and the car is beyond loud. My roommate described it as the evil offspring of a harley and a 747. I've already ordered a muffler and piping which should show up late this week or early next week. With luck this will keep me below the 92db track limit if not I got a supertrapp tailpipe insert just in case. The power, oh the power. I got just a taste until the motor cut out at 4k, no real boost even, and I can tell hell is just waiting to break loose.

I was able to fix the leaking brake line as well, it was the low pressure line but now there's air in the system so I'll need to bleed the brakes again. Also re-routed the fuel tank breather which seemed to help the gas fume smell in the cabin.

Now I'm counting the days, hours even...

[Wally]

350 hp would be extremely well done! fingers crossed.
Could not find what turbo you had bought for it?

[Humble]

The turbo is a punched out Garret T3/T04S hybrid. It's about the biggest T3 housing you can get .82 a/r and the T04S cold side is .70 a/r good for 60 lbs./min. or about 400hp.

[chug_A_bug]

I think I Speak for everyone, and Say WE NEED VIDEO of the dyno....
good luck


Chris.