Struts for my '70E Restoration

[tom1394racing]

I am restoring a numbers matching 1970 911E. The plan is to restore it to factory spec as much as possible, drive and enjoy it and then consider selling it depending on market value.

While I know that the hydro pneumatic struts were original equipment, I will be using a torsion bar suspension with early S calipers and deep sixes. I have a nice set of the correct option Koni 3.5" struts that I was planning to use however, I have been told that if I run the car at the proper ride height, these struts tend to bottom out under compression. I was told that Bilsteins do not have this problem.

I would prefer to use the Koni"s for originality but do not want to risk damaging them on our rough New England roads. Is there some way to avoid the bottoming while still running at the proper ride height? Alternatively, if I use the Bisteins, will that devalue the car from an originality stand point?

Appreciate any input.

[304065]

Tom,
Once you leave the hydros behind you can do whatever is period. Are the Konis bolt or wedge? If bolt ditch them.

I never heard of bottoming. Back in the day the ride height was pretty high- we tend to slam our cars today which can exacerbate suspension travel issues.

[edmayo]

Tom, all depends what you consider proper ride height. One of my cars was too low, had been that way for years, and yes as John said if they are too low they will bottom out the shocks. Since I had put a 85 liter tank in the car and often take long trips in it with a full trunk I raised both ends of the car, put on new Konis, and that has solved the problem. If you want I'll give you the ride height.

[tom1394racing]

This is the set I am planning to use. I compared these to the David Conklin photos of the low mileage '70S Benchmark and they appear to be the same.

Mine are in the tub and the other is the '70S benchmark car.

Ed......I would like to know what ride height you set.

[edmayo]

Tom, here are my heights, front, 25 3/4,,,,,,,rear, 24 1/4" This is lower than the heights the cars were delivered at originally, but not as low as the preferred "slammed" look. I lived with that for a lot of years but it just isn't practical if you actually drive the car on long trips. And that is with 195 X 65 tires.

[tom1394racing]

Ed

Thanks...I assume that is ground to top of fender arch?

[classic]

Not to thread hijack.....

Ed, for handling are you not better off setting up unsprung 36 degrees on the sping plate, and then adjusting to get the 108 + - 5 mm for the front, and 12 + - 5mm on the rear?

Or is it just a look preference. I understand the factory setup doesn't take into account the tyre size, compared to the fender measurement technique.

Just trying to understand.

[edmayo]

Not to thread hijack.....

Ed, for handling are you not better off setting up unsprung 36 degrees on the sping plate, and then adjusting to get the 108 + - 5 mm for the front, and 12 + - 5mm on the rear?

Or is it just a look preference. I understand the factory setup doesn't take into account the tyre size, compared to the fender measurement technique.

Just trying to understand.

When I was at the dealerships in the early seventies we did do the factory prescribed height measurement, but it wasn't long before people wanted to lower the cars a little. So then it came to be that fender lip to ground became the normal measuring method, because, in the end, that's what your eyes see anyway. So naturally following the old adage that "if a little is good more is better" so quite often the cars get set too low. Looks great at "cars-n-coffee" and they may handle better, but if you actually drive them on less than perfect roads you can run out of shock travel. As long as you understand the pitfalls then it's your decision what you want to compromise. In my case I've had this particular car since 83, and as it came from California of course it was slightly too low, and 7's on the back don't help the fender paint when the suspension bottoms on severe dips. I lived with this for over 20 years, had rear fenders repainted a couple times, but when I put in the 85 liter tank, and skid plate, I decided enough was enough. So I am now at a height somewhere between dead stock and previous too low! And Tony I think my spring plate angle ends up at about 34 or 35, not original 36.

[classic]

Ed,

Thankyou for the detailed explanation, I've been confused about the fender measurement technique for awhile. I'm getting close to stock at the moment, still adjusting and I'm getting more like 27" at the rear...... Doesn't look to rally if you know what I mean.