amr89c4

Ok, I know thats really asking for it, but I got your attention.

I finished the shock/spring job. See the quick pic. I'm happy camper so far. The perches are set with about 5 threads left at the bottom of the travel. Took car out for a short gentle spin (no alignment yet) to settle the springs and measured at the Porsche datum points and for fun, I measured at the fender lips on centerline with the wheel. Both fronts are at 25 3/4" and LR is at 24 3/4" and RR is at 24 5/8”.

At the correct datum points I got:

LF= 114.3mm RF= 123.8mm

LR= 235mm RR= 232mm

I thought I would go with RS+5 spec to hopefully reduce or eliminate the possibility of bump steer. With that in mind I’ll need to raise the front on both sides to about 130 and the rears need to be lowered to 223. What troubles me is that it looks like I'm already running uphill and if make the adjustments to RS+5 specs it will get slightly worse.
What am I missing here?

Oh yeah, the brakes and clutch feel better now than they ever have after the caliper, accumulator, valve body and clutch fluid flush.

Thanks,
Lynn

altarchsa

Looks high in front to me. Are you sure you went t the correct measurement points?

Did you do the Euro conversion? It looks about the same as my stock suspension. I thought 25 1/2" to front lip was typical for US cars. I would defineitely lower front if you have room in adjustment.

Heard from Grill lately?

amr89c4

Ok, I double checked the measuring points and the front end points are a no brainer compared to finding the rear points. Although once I found them they were easy to measure using a simple gauge I made that another member came up with (forgot who so i can't give credit). I multiplied the inches by 25.4 to get the mm.

I assure you that this was not stock height, because my stock height at the fenders was LF 27" and RF 26 15/16" before I started.

Thanks

velocitylover

It looks fine to me (I have the same year and model and mine is lowered to RS specs)

DanielT

forgive my ignorance, but what shock/spring combination did you go with?

looks slightly high in the front but definitely much improved from stock height

I will be doing mine soon.

amr89c4

I went with Bilstein HDs. RF part # F4-VE3-5278 H1and LF part # F4-VE3-5277 H1 and for the rears, part F4-B46-1735 H1 and HR Turbo 'Reds', part #29834. Aesthetically (sp), I think the rear needs raising or the front lowering. However, RS ride height spec (target) says I need raise the front and lower the rear. Go figure. I'm hoping to get some feedback on what I apparently missed.

DanielT

thanks for the info

and I do like your wheels

Dwane

As soon as I get a chance I will post pics.(92 C4)
Got mine corner balanced and ride height adjusted by an old school Porsche guy.
He wasn't sold on the facts in the 964 Companions Guide.(RS or ROW ride height)
DO NOT FORGET rake.....the car needs to be a touch lower in front than rear.
Bilstein HD with H&R greens.
She looked REALLY LOW when I picked her up.....She drives like a go-kart!
I'll try to get some more info.
later
Dwane

amr89c4

Thanks Dwayne,

Thats what was bothering me if I go to RS spec, which seems to be a popular setup. I'll have rake to the rear.

Unless of course the rake angle is measured from the side rails of the car, which I have not done. Seems I remember reading something about the rake and the ride height coinciding.

Let me know what you recall or a link to the info if possible.

Thanks

amr89c4

I think I finally dug up the now somewhat obvious answer to the apparent difference in gap between tire and the fender lip on the frt and rear as well as the mysterious 'rake' angle.

Someone noted that the frt wheel well is cut quite a bit larger than the rear to allow for travel and thus the apparent difference in tire to lip gap betwen the frt and the rear.

They also noted that whatever spec ride height you choose, if properly adjusted will account for the rake angle.

So I'm going to tweak the ride height to RS+5 and send her to the suspension tuner for alignment and corner balancing. Thanks to all who helped with this project. It was a great experience and I am satisfied the suspension will sort out nicely now.

Thanks

Computamedic

There is something strange with the front measurement. When I had my alignment done following the Bilstein/H&R Green fitment the numbers were 132mm (F)/ 231mm (R) which is a little higher than RS numbers. I think you'll struggle to get to those numbers with the H&R Reds since they are typically 10mm longer than the Greens.

I can only imagine that you're measuring the front at the wrong place. With my numbers the rake checks out OK. On the photo your car looks significantly higher than mine. My car is the yellow C4 in the foreground and there is a Guards Red RS next to it.

Regards

Dave

amr89c4

Could be Dave. I'm about 5 threads from the bottom of the lower thread range on the strut body. Here's a photo I used as a reference for measuring as recommended by others on the forum.

If you have other information, I'd appreciate it.

Thanks

warmfuzzies

Thats the pic I used, but, heres the rub, you're on a C4, so is it possible, or wise to go this low with the front drop links? the RS links are a tad shorter and when I changed mine out, did make a difference.

Kevin

amr89c4

Well, based on a lot of other C4 owners that did the same setup without issues, I thought I was safe. This setup has been discussed to death and I don't recall hearing of any issues unless you go too low. The short drive I took to settle the springs did not expose any handling or interference/interface problems. I'm sure the performance Pcar suspension shop guy will let me know if there are issues.

I will need parts for sure if I go below RS spec but setting at 5mm above should not be a problem based on the fact that I have not read or heard of anyone having a problem. I appreciate your input.

Thanks

TH996

Here's mine at 130mm and 25 7/8" in the front compared to a US Carrera Cup Car. I'll need to check for the rear settings. It has Bilstein HDs, H&R reds and RS Sways. Ride height, alignment and corner balance was done by Steve Alarcon at Johnson's Alignment in Torrance. It has no bump steer issues and handled great at Willow Springs.