Lowering a 308 with original Koni shocks

Hey, very nice work! Is this as far as you are in the project? Do you have a picture of the car with the "undesirable" height? How much lower are you trying to go?

 

Beautiful machine work.

 

+1. It is amazing to see the talents of F-chat members. Something new every day.

 

Great looking work. I have a question since I really know very little about this but like the idea. In lowering that perch doesn't that reduce the amount of "preload" on the spring and make the ride a little bouncy-er?

 

Love the idea specially if it lowers the car by an inch.

 

I was going to ask you why it looked like there was more material above the half-rings than the original design, but this explains it -- you'll want more (but please give me feedback about the A-arm clearance both as-now and if you go lower).

LQTM...

 

No, the spring rate of the spring is not changed and the load on the spring and length of the spring (chassis at rest) are unchanged (so the dynamic behavior is unchanged). There is definitely less vertical compression travel distance available to hitting the internal bump stop inside the Koni -- so if you were in a lengthy high-g corner on a track that would be a negative, but for rational street driving I never noted a problem.

As ztarum photo shows, most late 308QV ride particularly high -- here's where my ex-'78 308 (with 16" QV wheels) was after lowering the front 30mm and raising the rear 15 mm (have never seen a late 308QV that needed to be raised at the rear ):
Image Unavailable, Please Login

 

I have a 89 328 that is 1/2 inch higher on the passenger side. I have tried swapping springs left to right and it is still the same. I can use 2 of these perches. How much ?

 

I just put my front end back together and the car looks like it is going to be considerably higher than before and I was just mulling over exactly this same thing earlier today as an alternative to QA-1s. What a heck of a coincidence. I can do little things on my lathe, but I don't think I'm this good, especially in steel. Nicely done!

 

Ztarum,
So what clearance do you have now? below the front of the euro spoiler, i have a 1983 QV with the euro front spoiler and have to be careful with how low it is, but love the look.

 

Nice job Zack. Anxious to see it. We should go for a spirited drive when you're done.

 

Nice looking!

Alternatively, you could have painted a bunch of QA-1's red, of course...

Or use a shorter spring.

 

Thank you. That makes sense. So threading the shock for an adjustable perch would accomplish the same thing for those without a lathe or the skills to use one?
Your car looks great with that stance!

 

So where does one get that done?

 

Exactly the same situation -- the thread-adjustable lower perch just has more possible easily-obtained positions; whereas, each fixed lower perch only has one position.
However, IME the cost of the (deeper) fixed lower perch (maybe a couple~few hundred $ per pair?) is much lower than having the shock disassembled, a threaded collar welded to the shock lower body, and the shock rebuilt/reassembled (~$600 per shock last time I checked with Truechoice www.truechoice.com, but that was some time ago) -- however, if I was having my shocks rebuilt anyway, I'd probably opt for the threaded design.

It is true that usually people go to a higher spring rate when lowering since the range of motion is more restricted (so for the same dynamic load the spring deflection is less), but that does stiffen the ride.

I definitely prefer the 308 coachwork with a little forward rake stance-- but most have a backward rake stance in stock form.

 

Yeah I was just chatting about this with a fellow chatter the other day.

I'm really on the fence about doing this with 308 #2 vs. going for the QA1's. I'd be more inclined to do it if the threaded collars are available to just weld onto the shock bodies ... I had the feeling I had to thread the actual shock body to clear the spring, etc. but maybe not the case ... anyone sourced out the threaded pieces?

cheers

 

Would these work: (I think they don't weld these)

http://www.koniracing.com/sleeves.cfm

 

Someone needs to check the shock diameters AND the clearance between the i.d. of the springs ... I recall that being kinda tight on the stock configuration which is why I thought the bodies might need threading ...

Also, how much does the stock spring extend after you pull the snap ring? I remember doing this on a press one time and scaring myself worrying about the thing coming out in my face so I made some fixture with threaded rods to compress th spring which is a total PITA ... might of been talked about already ... might of been making a problem out of nothing.

cheers