Anyone with JIC Cross on early 964's?
 

My mechanic is in the process of installing my new set. He says that they seem short, compared to the stock setup. Obviously, you can thread the body up, but just wondering if anyone else has them? Porsche changed the rears for '91 I believe, made them shorter. I think he said the fronts are 2" shorter and the rears 1 5/8".
https://rennlist.com/forums/members/...9-p1010017.jpg

When I had the JIC Cross installed on my 1990 C2, my mechanic had a similar question. I purchased them through ViperBob in FL. My mechanic spoke to Viper Bob and the install went fine. I never did ask what if any problems he had, but the car looks and drives great. Maybe your mechanic could contact JIC or Viper Bob. Just a thought.

very interested in what happens seeing I might be picking these up!

I can't find anything on viper bob. I contacted JIC, nice people, a little hard to understand as their English is broken. They make a spacer if you don't want to go as low as they start at, I guess. I told the mechanic to give them a try, as I wanted the car a few inches lower anyway. What dampening settings did you have yours set at? Street use?

Yes, those parts are correct. On the 91-on cars, the bottom section of the rear shock is shorter (by a third or so) than the one in the picture.

As for being shorter relative to the stock part, keep in mind that the CROSS springs are stiffer and of a linear design, i.e. they will not compress as much as your stock coilovers when mounted (your mechanic should've known this). As for dampening setting, it depends on the springs you've picked. The stiffer the spring, the stiffer the shocks.

I'd start at the soft end and keep stiffening until you've minimized the float. Take a drive on a stretch of highway that undulates, if possible. As you move over these dips, the car will "porpoise" abruptly if you're under dampened--the springs are overpowering the shocks. Keep stiffening until the shocks reduce the excessive movement. The car should feel as if it's glued to the road surface.

Good luck and keep us posted!

Thanks for the vote of confidence, and the tips on set up. I will post many pics when the time comes that I get it back with all of the things I am having done. Probably another month, still waiting on Mahle.

Any time! :thumbup:

Here I set my at full firm. I drive it mostly on the track, with occasional street use, even though it is not heavily modified. Here a few pics after the suspension is installed. Not the best pictures, but it will give you an idea of ride height and look.

I have found that JIC "authorized dealers" have no idea how to properly set this system up for our cars. Cant really tell if that is a JIC issue or an over-zealous "dealer" issue. I suspect both are at fault.

I have mine set at 4 clicks from stiffest for the track as found any stiffer and the car would "hop" over little bumps like track turtles.

Marc

I guess they are meant to be primarily track items, very stiff and very low. I am dealing directly with JIC, they so far have been very helpful. I am getting spacers for the rear so that I am not too low. The guy above is a little too low for my taste on the street, and my mechanic says the rear fender is 1 inch from the tire with the adjustment all the way up. No problems with the fronts. I also asked for set up help from them for compression and rebound on the rears, so we shall see...

Thanks for the follow up. I'm wondering if you might be fine without spacers, though. You mentioned that the rear arch sits above the rear tire by an inch with the CROSS's maxed out? The height of most 964 tires is 25", provided you're running the stock spec. Add an inch and the arch height becomes 26" (approximately).

Here's what a car riding at 25" front and rear looks like. For a street car, I could understand raising the front another 0.5" but 26" at the rear would be close to stock. If that's what you're after, then have at it. It just seemed that spacers might be a bit much.

https://rennlist.com/forums/members/...5-0507-img.jpg

https://rennlist.com/forums/members/...-0505-imga.jpg

Yours looks nice, and yes, maybe a touch higher in the front as this will be street only, but that may be a front spoiler that I am seeing? I am running 17" cup 1 reps with normal sized tires, 205/50, 255/40. I guess I will have to try to get over to see the car, my mechanic is probably worried as I am doing such a drastic change that I might not like the low and stiff approach. After looking at recent photos of my car, there probably is 2" from the arch in the rear, but that is after it had been lowered on the perches a few years back, so stock might have been even more? Anyway, I will borrow your photo and send it to my mechanic, explaining that it might be okay as is. On the fronts, there is a screwdriver slot on top, and a knob up inside the bottom, is one compression, one rebound? I didn't receive any instructions at all, and this is my first set of adjustables, so please bear with the newb question.

No problem with the newb questions. Much cheaper than having it redone! ;)

As for the stiffness, you shouldn't be too concerned. I've driven my race car on the (brutal Chicago) roadways plenty of times. At their softer settings, it's really a nice ride--sporty yet compliant. The CROSS springs which are stiffer than 10kg, however, may be a bit much for a daily driver.

As for the front adjustments, these shocks are single adjustables, so the knob underneath is the only one that does anything. Basically, they adjust rebound and compression simultaneously. The valving relationship between rebound and compression is set by CROSS.

In the rear, the adjustment knob is in the engine compartment. I removed the heater blower and have a cone filter, so access is a snap. You can get to the right side by removing the airbox cover (no big deal) but you actually need to disassemble the heater blower to get a good grip on the left side knob. You can actually run your car without the blower until you get it dialed in and then reinstall.

Any other questions? Fire away!

Oh, here's another pic which is a little brighter and reveals the Ruf splitter up front. It's just a little lip spoiler but drops the front about an inch. And, yes, I scraped more than a few driveways with that thing.

https://rennlist.com/forums/members/...esclears2a.jpg

Which way is full soft? CCW? Assuming that it is the same for both front and rear. My mechanic says the rear is sitting at 26" with no engine, so he was concerned that it would sag too much with the engine back in. I guess they ballasted it and bounced the car the best they could and it dropped just below the top of the tire. I probably will go cone and am considering the blower delete just to clean up the engine bay(and to gain access to the rear adjusters!), has anyone finalized the fix for early cars deleting the blower? I need A/C, and don't want constant codes thrown.

Are your wheels 18"s? I also was considering that splitter, or the RS one, but that will be next years' project. Rennspeed seems to have the best selection of all the different types.