Section struts ... for those of us who didn't measure first

[heavy85]

OK ... so I just got the new RACE Koni's, I'm about to section my struts, and MY ENTIRE SUSPENSION IS APPART. I've read many posts as well as the FAQ on the subject but being that my suspension is completely appart I really dont want to put it back together to measure. I realize that ideally you would want the strut to be in the middle of travel at nominal ride height and that is how you should determine how much to section. I'm also in the process of relocating the LCA pivot up but not sure how much there either other than the standard 3/4-15/16" - again everyone says measure to figure it out. I'm moving the LCA pivot to move the roll center back up so I can lower the car some more without the LCA starting to point up. At this point I'm not worried so much about bump steer just improving the roll center & camber curve so I'm thinking I would want to move the LCA up as much as possible. My goal with the project is to maximize the handling characteristics for autox & some street duty.

 

So since many of you have probably already crossed this bridge any recommendations on how much to section the struts ... well and for that matter exactly how much to move the LCA (for the sake of allowing it to be lower without getting into a poor camber curve) since it's tied to the strut length.

 

PS - not sure if anyone else noticed this but the measurements from the casting to the factory spring perch in the FAQ are way off what mine are.

 

Thanks

Cameron

[JMortensen]

I'm not sure how long the Konis are. In my case with the Tokicos I sectioned the fronts 1 5/8" and the rears 2". If you could section them both 2" that would be ideal I think. You'll probably have to make a spacer for the rears, since you're using the same strut insert front and back. Do not section the rear to match the front or the *** end of the car will be dragging on the ground. Rear should be ~2" taller than the front.

 

I know John's FAQ says to section them right at the spring perch, but I still think it's easier to do right up at the top of the strut housing, especially with the Konis. If you don't get them exactly straight you'll be honing the tubes forever if you do it 6" down, but if you section right at the top the job would be a lot easier to fix. Either way works though.

 

EDIT--Should have said about 1.5" or 2" from the top of the strut housing. You don't want to cut the end too short otherwise its harder to get it aligned with the rest of the strut. I just hose clamped the strut to a piece of angle iron then clamped the top above it and welded the two together. Worked fine for me, but yours will be more sensitive to getting it perfectly straight because the Konis barely fit in the strut tubes anyway.

 

I'd go with the 3/4" up on the pivot unless you're really going to measure. Measuring is not hard to do, just requires a couple of dial indicators. I think you can get into trouble going too much higher than 15/16, especially if you have poly bushings, because the control arm can hit the inside of the crossmember if you go too high. If you're OK with measuring, then I'd slot the crossmember and move it until the bumpsteer is minimized then weld your reinforcing washers in that spot.

[buZy]

Did mine 3/4 up a while back. Moly arms with joints. From what I can remember at 3/4 up the stock LCA will have interference. You may have to grind some off your LCA to get clearance. Measure. Know what material you may have to remove before relocating.

 

[mom'sZ]

Worked fine for me, but yours will be more sensitive to getting it perfectly straight because the Konis barely fit in the strut tubes anyway.

Jon, one thing I wanted to mention was that the new koni's are slimmer and fittting them inside the 280 strut tubes is not a problem. You will also definitly need a spacer for the back.

[heavy85]

Jon, one thing I wanted to mention was that the new koni's are slimmer and fittting them inside the 280 strut tubes is not a problem. You will also definitly need a spacer for the back.

 

Mom'sZ - What gland nut did you use as I found out last night that the ones I have (were used with Tokico's) are just barely too small in diameter to fit the Koni's? Also, which direction is the bushing suppose to go? As JohnC pointed out in another thread the top is threaded all the way down but they provide a (sloppily fitting) bushing to allow them to go into the bearings in camber plates. Problem is that the bushing has a shoulder and is only about half as long as the camber plate bearing is thick so it's not obvious which way it's suppose to go - I'm not at all impressed with the way this bushing was engineered. I'm guessing the shoulder goes on top?

 

Ohh and FYI they are still very tight fitting to 240 strut tubes as I had to grind some of the paint off near the bottom of the struts to get them to fit.

 

Cameron

[mom'sZ]

Cameron: If your's is a 240 I'm not going to be much help answering your questions because mine is a 280. I used the stock gland nuts and they fit perfect. As far as which direction is the bushing suppose to go, what bushing? Do you mean the bushing that slids down over the threaded portion of the shaft? That bushing came from the camber plate maker, ground control. It was tapered on one end and slid down onto the shaft from above the camber plates tapered end first and also was a pefect fit. Where did you get your camber plates or are you using camber plates?

[heavy85]

Do you mean the bushing that slids down over the threaded portion of the shaft? That bushing came from the camber plate maker, ground control.

 

Yes that's the bushing but the only ones I have are the ones that came with the Koni's and those are the one which I confused about. I have the EMI camber plates but previous had Tokicos which are set-up to work with the plates without a bushing.

 

Now back to the original questions - since my suspension is completely appart where it would be a royal PITA to measure can anyone who has measured before like to give a recommendation for how much to section for the new Konis? The FAQ says 2" and 2.25" but also says to measure first and also that's with the old Konis. Since the new ones are 0.57" longer closed length with 0.39" longer stroke I'm thinking I should go another ~0.25" shorter but really dont think it matters that precisely?

 

Thanks

Cameron

[JMortensen]

Measure the old strut. Stick the strut down in the front housing and measure from the top of the strut to the top of the strut tube. Then do the same with the new strut. Subtract the difference, that's how much you want to section. I added 1/4" just as a little safety margin. When I was done I needed one washer in the bottom of the tube to get the strut tight with 2 threads showing on the gland nut.

 

Remember though, if it is too long you can shim underneath the strut. If it is too short, you're screwed. You'd have to resection the strut to add more material in.

[mom'sZ]

I read this somewhere, stick the insert into the strut housing tube. Thread the gland nut on. make sure the insert is fully extended. Let the insert sit all the way down inside the housing. put a piece of tape around the shaft where the gland is on the shaft. then pull the strut insert up against the bottom of the gland nut. measure the distance between the gland nut and the tape, that is the MOST you can section the strut.

 

Although you have disassembled the suspension on the car, you don't have to fully reassemble it to measure. Assemble one side front and back with no spring. Use a jack or what ever and test the travel of the new suspension. It's a good idea, just to make sure nothing binds or something funky. You will learn by doing it, don't bolt up or connect the sway either, just the strut and control arm. Use pvc pipe to make spacers. When you have the perfect length for the spacers, cut or have a metal shop make you some in steel or alum tube.