So I am think of putting the Koni yellows on the rear since they are already up front. I have a friend that is going to trade me the coil over setup as he can use the one I have on the reds and I need the yellows. Now, I need to know what size springs to get. I think I am going have him send me a set of 250s and 275s but I need to know what length. He says the ones he has laying around are 2 1/2" wide and 9" long. He think's his dad has 10" long ones. I need to know if these are the right sizes or if I need to look to another friend. Both will need to ship these and I don't want to have to ship back and forth. I would like to get it right the first time

are you going to use a threaded collar style adj perch?

Yes

i don't think a 1" dif in length is going to have a huge impact. there are a couple of dif lands for the clips and ultimately the ride height will be determined by the collar.

k

Kind of what I am thinking but it would be interesting to hear from the track guys as I am sure they will weigh in on this... maybe.

i added a picture above. you can see it but there is quite a bit of collar up in the spring. the package pictured is pretty easy to work with. the top retainer is a swell fit and didn't require any modifications.

k

The threaded perch is probably designed to work with a specific inside diameter (ID) of spring. So make sure you get the right ID. You also want to make sure that as the supension hits the bump stop that your springs don't bind first. That answers to "too short" question. Extra length just adds weight, but shorter springs may need a "tender spring" to keep the spring from comming loose from the bottom perch and top hat at full droop. But I have run other cars with short springs and no tender spring.

That's what I have on my reds now but I will need to get a different set for the yellows as I hear they are slimmer. Not worried about that part. Just curious as to the spring length and stuff like what richard mentioned.

So Richard, what length would you go with?

Wonder what legth JP's springs are?

Sorry, I should have mentioned above, that I have experience on other cars (such as my Civic that I used to autocross), but I have yet to buy springs for my 914 yet (car is still in 1000 peices all over my garage). Someone who has already done this needs to give you some suggestions regarding lengths.

My guess is something around 8" long is going to work (but I would get input from someone who has already done this first). I am also guessing that a 2.5" ID spring is what you need, but you need to validate that with whateve perch you have. IMHO, Eibach ERS springs are commonly used by many people and it's not hard to find used springs as people may swap them around until they find a spring rate they like. So used springs can be easy to find. And with an adjustable perch that has a lot of range it might be hard to go really wrong if you are in the 7-9" range????

Someone is going to post here with exact measurement as to what free lenght works well. I will be just as interested as you to see what they say.

Richard

John,

2.5" springs are what these sleeves I have are made for. Does anyone know the outside diameter of the Koni Yellows. I want to make sure that the threaded sleeves I have are the correct diameter. They work perfect on Bilsteins but I want to make sure that they will work on the koni yellows as well.

Kyle

Jon come over today and chk out the 76 which is equipped w/the exact setup
your talking about.
Oh ...you could PU the welder too.

those are the same springs and collars i had on the car when i ran ext adj yellows. same fit.

Yeah, they look the same but it is my understanding that ground control(or whoever makes them) asks you what shock you are ordering the collars for and then sends you the correct diameter centering ring inside the collar to fit the particular shock you are running. The Koni reds are like 2.10" or something like that while the Bilsteins are right at or just under 2.00" and I think the Koni yellows are the same as the bilsteins or a tad smaller. Basically, I you have 2" collars they won't fit on Koni Reds(the problem I am having) and if you have Koni red collars(2.1") they will be to big for Bilsteins or Koni yellows.

Clear as mud right?

Kyle

10 x 2.5.

I asked him to try and get the 10" from his dad but they are 500 miles apart. Anyone in Malibu want to grab some springs for me? The road to their house is fun to drive to. Okay, I am sure he will mail them to me.

Coleman racing sells their coil over kit for 40 bucks per side.
IDs of the sleeves come in 2 sizes 2.04 & 2.08. The Bils are 2.0 OD so some shims are wise. Measuring the OD of your shock is a snap, eh. Colman has springs for 56 bucks a pop.

Buy sumthin & get their catalog which has bout 300 pages of stuff.