Explain the 300 dollar shock to me, What the... Options

[emerygt350]

Just took her through some twisty mountain roads, roads with potholes, washouts, ripples, and poorly filled cracks. Very nice, can't feel any difference besides no more scary loss of control over bumps, that right side strut wasn't happy. Nice ride on the highway, otherwise not much different from the konis. No clue how the konis were adjusted. Probably pretty soft.

Here is the tag on the old konis


Everything went together fine, that big hold down thing didn't screw all the way into the strut but neither did the konis.

[mepstein]

At least on Bilsteins’ there is supposed to be a 2-3mm gap under the gland nut. This insures you are tightening the nut against the insert before it bottoms out on the strut body.

[emerygt350]

Ahh, well, I guess this is more like 5mm. It was nearly the same on the Koni. Maybe that is the point then.

[chmillman]

I'm tired of my bone-shaking Bilsteins... Really, really tired...

Late last year, had to replace a broken front Koni (that came with the car), my guy here suggested replacing both sides with Bilsteins and I said OK... There were already Bilsteins in the rear when I got the car.

Me and everyone else who has ever ridden in this car agrees it's now way too stiff.

I was looking around for alternatives and found this:



https://www.rosepassion.com/en/diagrams-por...1-103278-z90088

Real Boge's?? Didn't know they were made anymore. Look reasonably inexpensive too... Unfortunately, the rears are listed as out of stock...



https://www.rosepassion.com/en/diagrams-por...absorber-103279

I know AA has remanufactured both front and rear (further up in this thread). Shipping of a couple of rears to this side of the pond would be pretty expensive, and there is always the question if they even accept things with pressurized gas... @dr914@autoatlanta.com : you said above that they were manufactured in England... Any way to get them directly here in the "old world"?

EDIT: just found there are also front and rear KYB units available here… worth a try?

Also, I have no idea which springs/torsion bars are actually on the car. How to tell?

TIA

[mepstein]

I'm tired of my bone-shaking Bilsteins... Really, really tired...

Late last year, had to replace a broken front Koni (that came with the car), my guy here suggested replacing both sides with Bilsteins and I said OK... There were already Bilsteins in the rear when I got the car.

Me and everyone else who has ever ridden in this car agrees it's now way too stiff.

I was looking around for alternatives and

Real Boge's?? Didn't know they were made anymore. Look reasonably inexpensive too... Unfortunately, the rears are listed as out of stock...



https://www.rosepassion.com/en/diagrams-por...absorber-103279

I know AA has remanufactured both front and rear (further up in this thread). Shipping of a couple of rears to this side of the pond would be pretty expensive, and there is always the question if they even accept things with pressurized gas... @dr914@autoatlanta.com : you said above that they were manufactured in England... Any way to get them directly here in the "old world"?

Also, I have no idea which springs/torsion bars are actually on the car. How to tell?

TIA

99.9% have 17.9mm torsion bars. Larger diameter is aftermarket and not very common unless the PO was auto-x. or changed to 911/912 a-arms to use 18.9mm or bigger. Rear could be anything and difficult to tell if the paint is worn.

[chmillman]

Well, the car has had a 5 bolt conversion. So those might be 911 A arms, don’t know how to tell the difference.

[mepstein]

Well, the car has had a 5 bolt conversion. So those might be 911 A arms, don’t know how to tell the difference.

How was the conversion done. With redrilled rotors or a switch to 911 struts? Does it have 914 brake calipers or 911.

[wonkipop]

explanation?

you get what you pay for. (most times (IMG:style_emoticons/default/smile.gif) )

i've got the softest bilsteins.
a bit harsher than the old stock boges.

but i am not complaining.
even about the price tag which was not $5.59.
it cost $$$$ to get stuff to the antarctic research base at the bottom of the world.
live here and i will take your complaint about expenditure seriously. (IMG:style_emoticons/default/mad.gif) (IMG:style_emoticons/default/smile.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/beerchug.gif)

lets get serious for a minute.
even with a 72 horsepower cal spec 73 1.7 these here cars handle and go around corners.

they deserve every $ spent on a good set of shocks. (IMG:style_emoticons/default/beerchug.gif)
and a thorough going through of suspension components. bushes etc. you know the drill.
otherwise what kind of fun are you having?

i have a 1.8. and i sure am not enjoying its ability to peel its tyres off at the lights. (IMG:style_emoticons/default/biggrin.gif)
so................... (IMG:style_emoticons/default/confused24.gif)

[chmillman]

How was the conversion done. With redrilled rotors or a switch to 911 struts? Does it have 914 brake calipers or 911.

No it’s full 911 brakes with vented rotors on the front, so I guess the struts are also 911. So maybe the stiffness of the ride is coming not just from the shocks, but also the spring rate… When I get the car back up on the lift, I will try to see what diameter they are. Does that mean I need to be looking for 911 inserts for those? Is there a difference?

Again, for the rear springs no idea what they are, they look newish, black paint perfect, no rust, but no markings I could find either.

@wonkipop - I tacked my request to the end of this thread instead of starting a new one because it mentioned the Boge replacements made by AA. So the title is a bit OT relative to my issue, personally money spent is not an issue, getting a better ride is.

[mepstein]

If the struts have been switched out, you need to figure out if they are Boge, Bilstein or Koni and if the caliper spacing is 3” or 3 1/2. Early 3” Boge 911 struts will take the same Boge inserts as a 914 but everything else is different.
The most practical way to tell if the torsion bars are bigger is to measure them. If they are 911/914-6 size, they are 1mm larger. That makes them stiffer but doesn’t automatically make them “harsh”.
So the first step is to figure out what you have so you can decide on the best solution.

[chmillman]

If the struts have been switched out, you need to figure out if they are Boge, Bilstein or Koni and if the caliper spacing is 3” or 3 1/2. Early 3” Boge 911 struts will take the same Boge inserts as a 914 but everything else is different.
The most practical way to tell if the torsion bars are bigger is to measure them. If they are 911/914-6 size, they are 1mm larger. That makes them stiffer but doesn’t automatically make them “harsh”.
So the first step is to figure out what you have so you can decide on the best solution.

So, the bolt center to center spacing on the calipers looks to be around 76mm or 3", so older non-S 911 parts I assume.



Viewed from the front they look like this:



The green dust cap up top looks newer than the strut itself...

And I did actually find a marking on the rear springs...





Did a search for the number but didn't find anything right away, but I assume SP100 indicates 100# springs? (more or less stock... hopefully not 100Kg...) 912 parts?
Edit: AI is telling me they are probably aftermarket from Weltmeister.

The sway bars are 15 front / 16 rear (stock option size)

[mepstein]

It looks like the strut uses an early pinch bolt (large nut securing the bolt, split between the ends that secure the ball joint). If that’s correct, they are probably early 911T struts and probably Boge. Boge struts will have an embossed area halfway up the body with Boge name and part number. So long story short, if they are Boge 3” struts, Boge replacement inserts will drop right in. Easy to do at home. Jack up the side of the car, remove top nut on strut, drop the strut under the fender lip, pipe wrench to remove gland nut. Install is reverse but use a jack under the ball joint to raise the strut back into the strut retaining area on the car. Takes 15-20 minutes per side. No need to remove the entire strut from the suspension. Just be carrot the paint on the fender.

Personally, I would do the fronts and take it for a drive. You might not need the rears done. The front controls 75% of the feel of the car.

I could be wrong but the 914-4 rear sway bars were 15mm and 914-6 were 16mm. Not a significant difference in feel but if it’s a bar for a six, it’s pretty valuable compared to one for a four. At least to an owner of a real six. You can also disengage the rear bar and see if you like the ride. Using a rear bar isn’t mandatory on a 914. Some guys control the roll with just springs. Maybe a bit more understeer but it’s a common setup to just use a front. Easy enough to try it and see if it works for you.

[wonkipop]

How was the conversion done. With redrilled rotors or a switch to 911 struts? Does it have 914 brake calipers or 911.

No it’s full 911 brakes with vented rotors on the front, so I guess the struts are also 911. So maybe the stiffness of the ride is coming not just from the shocks, but also the spring rate… When I get the car back up on the lift, I will try to see what diameter they are. Does that mean I need to be looking for 911 inserts for those? Is there a difference?

Again, for the rear springs no idea what they are, they look newish, black paint perfect, no rust, but no markings I could find either.

@wonkipop - I tacked my request to the end of this thread instead of starting a new one because it mentioned the Boge replacements made by AA. So the title is a bit OT relative to my issue, personally money spent is not an issue, getting a better ride is.

was addressing OP (emery350gt) not you chmillman (IMG:style_emoticons/default/biggrin.gif) sorry for confusion.

for emerygt350's interest i found my receipts for the billsteins back at end of 2019.
B6 bills.
front pair $847 AUD
rear pair $770 AUD
googling the AUD back then - 1.00AUD = 0.72 USD
cost for pair of fronts $609.00 USD. or 300 each.

same price as now by the looks of it. zero inflation?

@chmillman - back in 2019 you could not get boges or boge replicas from mr atlanta.
choice was between billsteines and konis. don't think even cheapos were an option for me in north antarctica. not even available.

truthfully i would not have minded boges again (if they existed) as the car has factory sway bars. allow for the softer shocks in a kind of comfort/performance compromise.
most of the time the B6 are not too bad comfort wise.
but definitely a bit stiffer.

re your springs. not sure 100 lb springs are original spec.
others here know more.
i have a vague recollection the originals were in the 50-60 ib range.
there is some figure in the factory manual which is in kp.
seem to remember something about three different strengths.
but can't remember how that worked. someone here would know.
i reused my original springs. seems to be working ok with the B6s i put in 5 years back.

[chmillman]

i have a vague recollection the originals were in the 50-60 ib range.
there is some figure in the factory manual which is in kp.
seem to remember something about three different strengths.
.

Yes, the manual has 3 different values from 220-240 Kp - those are minor differences, possibly to keep springs matched due to manufacturing differences at the time.

60 pounds/inch is about right... Here is the calculation I infer from the manual info

Spring free length=471mm
The 220-240 Kp value is measured at L1=239 - from that I infer that the spring is compressed to that length to measure. That means a compression of 471-239 = 232mm or 9.13"

240Kp*2.2=528 lbs force at a compression of 9.13"
528/9.13 = 57.8 pounds per inch.

Hope i got that calculation correct.

[wonkipop]

i have a vague recollection the originals were in the 50-60 ib range.
there is some figure in the factory manual which is in kp.
seem to remember something about three different strengths.
.

Yes, the manual has 3 different values from 220-240 Kp - those are minor differences, possibly to keep springs matched due to manufacturing differences at the time.

60 pounds/inch is about right... Here is the calculation I infer from the manual info

Spring free length=471mm
The 220-240 Kp value is measured at L1=239 - from that I infer that the spring is compressed to that length to measure. That means a compression of 471-239 = 232mm or 9.13"

240Kp*2.2=528 lbs force at a compression of 9.13"
528/9.13 = 57.8 pounds per inch.

Hope i got that calculation correct.

thanks for translating my rubbish memory re rear springs into something factual. (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/beerchug.gif)

out of interest i just did a calculation on the rear boge shocks screen grab you posted above.
1 swiss francs currently = $1.90 aud. so cost would be $176 aud for each shock.
+ GST 10% payable when its landed in aus. good as $200 aud. + freight. thats a stab in the dark. but given its heavy-ish. wild guess. $50.00 aud.
so i'd be looking at around $250 aud per rear boge shock.
not too much different to billstein. maybe $100 cheaper but that depends of freight. though i have not checked bill prices in aus currently.

[emerygt350]

If it makes any difference, I have been enjoying autoatlantas boge struts. I did quite well with them and my all season radials at my last autocross. They are not crazy different from the adjustable konis that where in there but my suspension response is probably a bit different than normal with my 14 inch wider track width than a stock 914.

[carr914]

@Paragon

Jason can answer all your question. He is The 914 Koni Guy