• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Koni or Bilstein? 740 track car.

poulrais

poulrais

Well-known member
Joined
Sep 8, 2006
Location
Quebec, CAN
For a track car that will see some road use what would be the best choice for 2 way adjustable front struts to use with coilovers on a 740? The car is a forged T6 swapped project and it has an S14 rear IRS subframe with QA1 double adjustable coilovers.
 
Swedbrick said:
I like my Koni's, bit stiffer than Bilstein in comparison. GAZ also makes nice inserts.
Click to expand...
I checked the GAZ inserts but they seem to have only a one way adjustable version. Do you have the Race or Sports Konis? What is the Koni part number?
 
Not a fan of the koni adjustables. I've had them on my race car and street car and compared to the custom valved billys its not even close. The koni's are just unnecessarily harsh no matter the spring rate in my experience. The Billys are also a mono tube design which from everything I read is better for performance
 
RoadRacer4Life said:
Not a fan of the koni adjustables. I've had them on my race car and street car and compared to the custom valved billys its not even close. The koni's are just unnecessarily harsh no matter the spring rate in my experience. The Billys are also a mono tube design which from everything I read is better for performance
Click to expand...

I've had the opposite experience, I have found konis to ride much better than Bilsteins when everything is set up correctly.

With an adjustable suspension, its easy to get bad results if you aren't tracking the all the settings.
 
poulrais said:
Do you have a part number for the JRZ inserts?
Click to expand...

JRZ doesn't do inserts, they do standalone dampers,

We have these custom built into the spindle, the outer housing is the damper body.

ProCropped_1024x1024@2x[1].jpg

Last time I checked they weren't interested in doing any for the 740, I can check again but I sincerely doubt they will without a large volume commitment.
 
poulrais said:
I checked the GAZ inserts but they seem to have only a one way adjustable version. Do you have the Race or Sports Konis? What is the Koni part number?
Click to expand...


We have single and double race koni dampers available here

www.bneshop.com

700/900 Koni Race Dampers

We are offering a several different Koni Dampers, each are best when used in the correct application. The Koni RACE series dampers are designed as a bolt in application for those running either in high performance driving events, road racing or autocross. The travel range on the RACE dampers...
www.bneshop.com www.bneshop.com
 
poulrais said:
Do you have a part number for the JRZ inserts?
Click to expand...
It's... not that easy. I was being 50/50 serious/facetious. But they are really good dampers!

The RS Line of JRZ dampers are actually pretty affordable (remember, I work in motorsports, hahahaha!!!) and they will definitely have something that can be made to fit, and you can actually get pretty clever with the valving to make something not far off of a real racing damper.
 
If you aren't tracking telemetry and lap times, any tuning is subjective... As are the results 🙃

IME clickers and adjusters usually lead people down a path that makes things worse.

Any single piston damper can be tuned to act just like (or verrrrry close to) any other damper, when you start adding high/low speed or travel dependent valving this strays. Knowing what you want from a damper is the most important part. With respect to Koni vs Bilstein, it's generally easier to get a Bilstein revalved than a Koni in the US. I've had 46mm inverted bilsteins valved to match a set of adjustable Reigers we had. You just need to know what you want, or work with someone who does... RIP Chris Billings

 
RoadRacer4Life said:
Not a fan of the koni adjustables. I've had them on my race car and street car and compared to the custom valved billys its not even close. The koni's are just unnecessarily harsh no matter the spring rate in my experience. The Billys are also a mono tube design which from everything I read is better for performance
Click to expand...
If you say so. My black daily driver has 250lb coil springs and koni yellows and on the softest setting it beats your teeth out. Ditched the koni's and installed some used stock billy HD's and its better in every way. My race wagon has 400lb springs and revalved bilsteins and it's super solid. Depending on the track we swap between 400 and 450lb springs.
 
Swedbrick said:
I like my Koni's, bit stiffer than Bilstein in comparison. GAZ also makes nice inserts.
Click to expand...

Just the sports in combination with ipd springs, my brother's car has the GAZ dampers with the same setup otherwise, which is a bit more plush.

I prefer the rear GAZ adjusters though, the koni's have to be taken out which is a pain. I tend to just leave it slightly overdamped to sort the occasional towing duty
 
I don't know what the Koni's are like these days but the faff of adjusting them always put me off. Gaz have always worked well for me. B6's revalved will work well it just get costly making them work well enough
 
RoadRacer4Life said:
If you say so. My black daily driver has 250lb coil springs and koni yellows and on the softest setting it beats your teeth out. Ditched the koni's and installed some used stock billy HD's and its better in every way. My race wagon has 400lb springs and revalved bilsteins and it's super solid. Depending on the track we swap between 400 and 450lb springs.
Click to expand...

How much droop and compression travel did you have with your ride height settings at the 250lbs?
 
Not a track car but my Billy's compress my spine 100 times more than my Konis ever have, and that's just on regular roads
 
I'm no racecar engineer, but I had 250 lb/in front springs with the koni sports set to full stiff and they felt a little under-damped. I changed the front springs to 200 lb/in (koni's still at full stiff) and I like the feeling much better. Neither setup was harsh in any way, but the 250 lb/in springs felt a little bouncy. Now the car feels very smooth.
 
sloopy said:
I'm no racecar engineer, but I had 250 lb/in front springs with the koni sports set to full stiff and they felt a little under-damped. I changed the front springs to 200 lb/in (koni's still at full stiff) and I like the feeling much better. Neither setup was harsh in any way, but the 250 lb/in springs felt a little bouncy. Now the car feels very smooth.
Click to expand...
I really don't know at this point which spring rate I'm going to put at the front. I have #200 at the rear on the QA1 coilovers that are double adjustable. My 740 is probably a little more nose heavy than stock with the forged T6 motor and CD009 tranny. I was thinking about starting with #250 or #300 in the front.
 
You must log in or register to reply here.
Back
Top