Shocks vs. ride height help!

JackS · 06-07-2003, 07:59 AM

I just replaced my rear shocks with some new Koni's on my 74 911. I have them set all the way soft to break them in. I have noticed that my ride height is a little lower with the new Koni's and I actually get a little fender rub. If I adjust the shocks to a firmer setting, will it reduce the body roll so that the rear fenders don't rub? Or do I need to start thinking about raising the rear a little. Will a firmer setting raise the body a little more? Please help me suspension Guru's!

masraum · 06-07-2003, 08:11 AM

I could be wrong, but I don't think that a firmer setting on the shocks will raise the rear. I may keep the rear from coming down as far when you hit a bump, corner, or accelerate, but even then they aren't really designed to limit range of motion, just slow reaction, so I think you are going to have to raise the rear.

JackS · 06-07-2003, 09:30 AM

I'll try it. The KYB Gas shocks that were in there gave me the right ride height. One would think that new Koni's would lift it up more if anything. I hate to put the KYB's back in. Anyone else have this problem?

nostatic · nostatic's Garage

don't know if this is a relevant data point but I remember running KYB shocks on my bug raised the rear relative to what I had before and after. I'd say stick with the Koni's and adjust the ride height to taste (mmm....tasty oil)

dhaines · 06-07-2003, 09:41 AM

If they are Koni orange/red shocks, I believe the adjustment only effects the rebound, not the compression. Koni's home page has some articles you may want to look at. I think the main difference is going from gas to oil shocks and you will need to have the height reset. I am far from an expert though!

masraum · 06-07-2003, 09:48 AM

If the ride height was changed by the shocks then either the KYB's were gas and the Koni's are hydraulic (gas charged has a bit of lifting action, while hydraulic only dampens) or the KYB's have a much stronger gas charge than the Koni's. I vote for option one.

marcesq · marcesq's Garage

Been there exactly. KYBs are gas charged shocks, Konis are not (some have a slight gas charge, but depend on oil for the most part). When I replaced my KYBs with Koni's the rear came down. Time to re-adjust the ride height.

I would set the rears at one turn off full and leave it there depending on what you have in the front. I set mine: rear 1 turn off of full hard, front 1.25 turns off of full soft. You want the front of a 911 to rebound quicker than the rear.

Koni's only adjust for rebound, not for compression.

JackS · 06-07-2003, 10:57 AM

The KYB's were indeed gas shocks. I should have listened to the voice in my head that kept telling me to go for the Bilsteins. Thanks for all the excellent advice. It looks like I need another trip to my Porsche guy for the rear height adjustment.

marcesq · marcesq's Garage

Quote:

Originally posted by JackS
It looks like I need another trip to my Porsche guy for the rear height adjustment.

Wait . . . . does your car have the adjustable spring plates by any chance . . . didn't come on a '74, but lots of people retro-fit them. If you do it may be that your shop misses this project.

If you have them send me a PM and I'll walk you through the project.

JackS · 06-07-2003, 11:49 AM

Thanks Marc. No I don't have the adjustable spring plates. Is it worth buying them now prior to the adjustment? As long as they have to take everything apart, maybe I should have them throw in the adjustable spring plates. Your thoughts?
BTW...It's raining cats and dogs in Massachusetts. No Porsche drive today.

dhaines · 06-07-2003, 11:49 AM

BTW, J Walker told me he as a rule sets Koni's to one turn less than the firmest setting. We all know he is god! ;-) Sounds in line with some of the advice above.

marcesq · marcesq's Garage

Quote:

Originally posted by JackS
Is it worth buying them now prior to the adjustment? As long as they have to take everything apart, maybe I should have them throw in the adjustable spring plates. Your thoughts?
BTW...It's raining cats and dogs in Massachusetts. No Porsche drive today.

Jack:

YES!!!!! You can pickup a set from one of the grave yards for 100 bucks. You are looking for spring plates for years '77 to '85 (years that the 915 was used). Replace the bushing with Neatrix. If you want to go high end, pickup the Sway-A-Ways for 350.00.

Rain . . . . someone moved Seattle to Reston, Va for the last 35 days. We had 3 inches today.

JackS · 06-08-2003, 03:59 AM

Thanks Marc. I'll poke around the local salvage yards. Are they difficult for diy installer?

JackS · 06-08-2003, 03:59 AM

Thanks Marc. I'll poke around the local salvage yards. Are they difficult for diy installer?

JackS · 06-08-2003, 03:59 AM

Thanks Marc. I'll poke around the local salvage yards. Are they difficult for diy installer?

marcesq · marcesq's Garage

Wow, now that is a showing of real appreciation.

No not difficult if you have done other work on your car, or cars in general. There are a couple of very good tech articles on the home page of our host under 911.

Also, I would be happy to spend as much time as you need talking you through the process. Very satisfying project to complete. Send me a PM with your phone number and we can bat it around, then you can make a decesion.