TJ Elliott

I'm just about to pull the trigger on ordering parts for a suspension upgrade to my sons 1986 944 Turbo and keep waffling on the Bilstein versus Koni question. The car is a daily driver during the summer months and sees about 15 DE days per season. My son and I run in the advanced (black) driver group with our local PCA region.

The plan is to delete the torsion bars and run a coilover set-up with 400 lb front springs and 600 lb rears. The car already has Pohlman front control arms with mono ***** and solid castor blocks, Racer's Edge camber plates, strut brace and front and rear 968 sway bars with front support brackets. When deleting the torsion bars I'll eliminate all rubber in the rear and replace with Elephant Racing (polybronze) and Racer's Edge bushings and monoballs and Tarett drop links.

For front struts and rear coilovers I'll either go with the Ground Control Koni set-up with Eibach springs or the Bilstein Escort Cup set-up with Hypercoil springs. I've searched and read most posts concerning the Koni versus Bilstein question and see a bias toward the Bilsteins. However, I note that the Bilstein set-up has rubber inserts in the rear coilovers and technically wasn't designed to run without torsion bars but many do. The Koni's on the other hand have monoball ends and would be installed with the Racer's Edge lower mounting bolts.

So the question is, do I go with the preferred Bilstein Escort Cup/Hypercoil set-up with rubber in the mounts or the Ground Control/Koni/Eibach/Racer's Edge set-up with monoball mounts?

TJ Elliott

Guys what's up? Over 115 and views and not a single comment or opinion! Where are the guys that track their cars and have modified their suspension?

Perhaps I need to reword my question. After spending the time and $ to eliminate all the rubber from the suspension would you install the Bilstein rear coilovers with rubber mounts or go with the Koni set-up with monoball mounts to completely eliminate all rubber?

David Floyd

I think you will find both options will work but.... the rubber working better for the street, monoballs better on track, 400lb 600lb will be a little soft for the track so where are you willing to give ?

IanM

Ahh I miss the 951 board, so I might as well post.

When I had my '89 951, I started off with Koni. Had my front M030's rebuilt and revalved, 300# springs, 28mm torsion bars and new koni yellow rears. It was ok, but was way too soft once I started running R-compound tires, and too much understeer in slow corners. I'm sure I could have found a better Koni setup (for example, the Koni 'Cup' setup sold by Paragon looks very nice, and uses the 30-series Koni race coilovers in the rear).

However, when Pat Aylward offered to sell me his Bilstein Escort Cup setup I jumped on it. I tried a variety of Hypercoil spring rates, and ended up at 425# front springs and 600# rear. I absolutely loved my Bilstein setup, and yes I ran my rear coilovers with the rubber mounts and t-bar delete. With that setup plus Racer's Edge front camber plate and rear delrin spring plate bushings, Weltmeister swaybars, I ran same size tires front and rear, and the handling was incredibly neutral on the track. I still drove on the street, and I didn't consider it to be too stiff for street use. That car was dialled in beautifully.

My laptimes at the tracks I drive are all several seconds quicker in my GT3, but I do miss the handling of that 951.

fejjj

Thanks Ian.

cruise98

I have had both and prefer the Koni's for the street. There are pros and cons to each one, just like everything else in life. I am running rear coil overs with 550# springs, Elephant spring plate bushings and no t-bars. It is a surprisingly nice ride. The fronts are Koni's with 340# springs along with GC housings and mounts.

I wish you luck in making this decision. We all have had different experiences and our butt shock dynos are not calibrated the same.

CBRE

Ive had both back to back and like the Koni's way better.

TJ Elliott

Was considering the 450 f/700 r initially but I thought it might be too stiff for the street which is where the car spends 90% of its time.

BTW I'm looking at the Escort Cup combo with the rear coilovers not the Firehawk. I edited my initial post. Maybe that caused some confusion..

TJ Elliott

Care to elaborate? Was it a compliance/ride quality issue? Do you recall your spring rates for each?

Thanks

TJ Elliott

Excellent, thank you.

Van

I'd go with the Konis. Because they have the single adjustment, you'll be able to fine tune them to match your spring rates.

I think the Bilstein Escort Cup shocks are a better shock, but unless you have them valved specifically for those spring rates, I'm not sure you'll feel a performance gain with them.

PJR1976

Having used both Koni and Bilstein over the years on the street I did not see so much performance difference between the two, although the Koni's always felt softer (maybe smoother) on the road. However, in the colder climates the Bilstiens seem to hold up better.

Perhaps the difference is felt on the track... Ernie Jakubowski of Mantis racing who builds, races and actively competes in the 944 Cup and has won numerous times (also he helped build Bill Comats car who has also won) use the Koni set up.

I was leaning towards the Bilstien Cups but after seeing how well Ernie sets these cars up and how successful the cars he builds seem to be, I am now leaning towards the Koni's. Plus the Koni's cost less.

The caveat here is... valving correctly + spring rates with any set up seems to be key, the overall set up of the car / other suspension components defiantly comes into play. Choosing the right shock/spring setup is not the only consideration. Last point... driver preference and driving style.

Do you know any local guys that you could try out their cars maybe with the different setups?

Kris H

I have konis installed, but a lot of my friends have GAZ shox.. anyone of you had any experience with those?

C ANDERSON

They both will work for you, I do think your spring set up is a little weak for track.
I currently have the Ground control on 1 car with 550 frnt and 700 rear no rubber in any position. car rides well on the street . Handles very well on track could actually be a bit stiffer on springs.

I have CRUISE98'S old Bilsteins on my street car with correct if wrong Keith 175 progressive springs on front standard S2

C ANDERSON

Sorry accidentally hit enter ..... any way S2 torsions on rear still all rubber still in. Just ran the car at NOLA at the instructors school and handle well enough for the power and street tires . However this car on the street rides rougher on the street. Still handles way better than before the Bilsteins were installed. By no way would change it, I dont mind a stiff ride .
Also rode and drove CRUISE98'S with his set up also rode with him at NOLA Motorsport park , have to admit that set up is the best of both worlds . rides better than any of my cars and handled the track well too. with slicks it probably needs to be stiffer.
You just have to decide what the cars main use will be and how much ride quality you want to give up
Clifton Anderson