So my new '74 and I are getting to know each other now that I've fixed the brakes. We went out for a spirited west Sonoma County run yesterday, and I found that the rear is too happy to come out with throttle lift and throttle input.

Unfortunately I don't have all the suspension numbers, as it was three owners ago that the car was setup for auto-x'ing. Little information was been passed down from one owner to the next.

What I do know is that the car is stiff, much stiffer than stock. I pulled the rear springs and shocks and replaced them with yellow adjustable Konis and 185# springs. I can't tell any difference in the spring rate, so I think they too were in the 180# range. Either way, there was over steer before I made the swap.

The fron tend is also beefy, though I don't know the size of the torsion bars or of the swaybar. Certainly a lot heavier/bigger than stock. The swaybar is adjustable, and I've included a photo of how it's currently configured. To "loosen" the bar up, I'd need to put the drop-links on the furthest part of the lever-arm, right?

Also, does the angle of the lever-arm look like it's aiming too high? Should the drop-links be shorter to make the arm more parallel to the ground? I have a fully adjustable bark with a adjustable drop-links that I should probably just install, but doing so is rather low on my list of things that need to be done to the car.

correct. but since you want to tighten the bar (ie make the bar more effective to control your car's tail-happy tendencies), move the drop link 'in' (towards the bar).



yes. i'd replace the droplinks to the adjustable type.

have fun with it!

Ah, not sure why I thought I should loosen the bar. Glad I asked first!

I had a set of adjustable drop links ready for installation.

Thank you!

Those are 911 drop links and not 914 drop links. The 914 links are shorter (and I hope your adustable ones are shorter than the pics)


B

Ahh, so that's what's going on there. Thanks for the info.

My adjustable drop links are 914 specific, so they should be the correct length.

There might be a lot of people that think you should change away from braided brake lines too

I, too, have stainless braided lines. Why change?

I've always had SS brake lines, though I wasn't the one who installed the lines on this car. In fact, they're old. Probably 8 years + and should be changed either way.

I'm all ears regarding the pros and cons of SS lines for street use. If they're DOT legal, they MUST be safe, right? haha

This is one of the big reasons. You can evaluate the age of rubber lines with a glance. All but the most diligent owner are more prone to seeing SS lines that have no outward evidence of wear and ignoring them. Meanwhile the tubing is collapsing inward and reducing the flow to the calipers.

Is there a rule-of-thumb regarding how often they should be replaced? 2 - 4 years?

Unless you have a lot more power than a stock motor will give you, stepping-out on throttle-on is unusual. Mine has only done that when I had toe-out in the rear (which is really wicked, and can be a recipie for snap-oversteer!) or when the rear suspension has bottomed out.

You might want to check for those conditions. An alignment shop can check the rear toe angle, and you can put a zip-tie on the shock rod to see if it is collapsing all the way.

Note that ride height can have an effect as well--if you lower one end of the car, it will usually tend to stick better.

--DD

Thanks Dave! I'll have a lot to play with after tonight. I'm getting my Falken RT615's installed and I'll be lowering the back down to where it was/should be. I'll have the allignment checked out once I *find* and install my turbo tie-rod kit (I know it's here somewhere!). Oh, and I need to put the adjustable down links on too. Whew! I'll test the car's steering after each change to see where it stands.

this doesn't make sense to me...

All I can think of is: weight


B

yeah, that's what i was thinking, but you raise a corner to put more weight on it...

I have braided lines on my car, but I am planning on changing them (I don't have very many miles on them).

I have heard many times people whom seem to have many years (more than 10) talk about how bad braided lines are, so my opinion on the matter has been developed from listening to them, and not from personal experience. The opinons on the matter seem to be virtually unanimous, so I listened .

AFAIK - the story is that the braid traps dirt between it and the line. Since that line flexes a lot, it's easy to slowly erode the line under the braid, and it makes it hard to see when the line under the braid is in bad condition. I think the failure mode of braided lines is bursting (READ: no brakes anymore... hello coffin), where the normal rubber lines just get spongy (READ: my brakes are spongy, better look into that), and take longer to fail as well.

I *THINK* the prevailing wisdom is that if you must run the braided lines - you should replace them once a year, and inspect them carefully and often. I believe that the preferable solution is running normal rubber lines.

I personally wish that this had been this clear to me before I put braided lines on my car since now I need to change them again and do all that bleeding bullshit again .

Lower CG, more negative camber. Lowers the roll center, too, but it's easier to go too far on that...

--DD

Fiid,

leave your lines on the car. Unless they are more than 8 years old.. leave them alone. The ones that *CAN* cause failures are the ones sold way back in the day that had NO bend restrictors on the ends.

I have yet to see a factory Porsche race car come out of the factory with rubber lines on it. 100's of Porsche Motorsport engineers cant all be wrong. The key is: (with any performance car) CHECK THEM on occasion. I still havent seen a failure do to a braided brake line. I'm averaging 10 events a year. All the crew people talk. all the shop owners talk.. all the racers talk... the bulletin boards would be full of it.. I still dont see or hear about these failures (besides Capt Crusty)

Show me. Prove to me how bad they are. I installed my first set in 1994. The car runs and drives fine to this day. It is a 450hp V8 914 with a 930 4 speed box. The car moved to SD before I did.. now I get to drive it/see it every few weeks. Same car I built in 1994 with the exception of the interior/tires/water pump.


B

if you're talking corner balance, then *no*, you don't raise a corner to put more weight on it. you're raising a corner to level out the diagonal "plane" the car is sitting on so it doesn't "pivot" around that plane no more ...

Andy

touché, sir sauerkraut...

This works in the cross weights, but all the stocker 914's running around on bad rear springs have a LOT more rear grip than front grip

Of course, we all know that the cross weights are more important than the front to rear bias.



B

easy to fix throttle lift over steer.
DON'T LIFT THE GAS PEDAL IN A TURN
if you start sliding the rear on the street stop what you are doing and get your head checked "you are nuts"

if you get the rear stepping out on a AX course mash the gas so as to transfer weight to the rear wheels. it will stick.