Transverse rear spring rate adjustment ponderings.
- Thread starter 69427
- Start date
69427
The Artist formerly known as Turbo84
Oh, certainly. This is the fourth spring I've modified to fit my narrowed suspension. I estimate it changes the rate by 5-8 percent, and as I don't have a convenient fixture to actually measure it, I just compare the non-modified rates to each other when trying to decide which way to go and how much when considering a spring change.
69427
The Artist formerly known as Turbo84
Spring update: Had a track day yesterday, and things went exceedingly well. Nothing broke, and the car was truly enjoyable to drive fast. The new rear spring (Thanks again Jim 
) worked very well, and survived the abuse. The car was very well balanced, with just a hint of controlled oversteer which helped rotate the car around the tight corners. I've owned this car for decades, and was never able until just recently to flick the car back and forth through a slalom environment like it will do now. I did experience a bit of tail wagging under heavy braking, but I think I can clean that up with some geometry tweaks to the rear toe rods. I'm suspecting I'm getting a touch of rear toe changes under braking, so I'll do some measuring of things to see what I need to do to rectify this.
Had an enjoyable time mixing it up on the track with a guy in a new 911. A very pleasant guy, after that first session he stopped over where I was parked and he complimented me on the car's performance, and was curious how my antique (my label, not his) handled that well. We had an enjoyable discussion.
One other item. One of the spectators stopped by and complimented me on how my car sounded. I thanked him for going to the effort to walk over to say that. I didn't bother him with details, but I was happy that my efforts fabricating the mufflers and resonator paid off. I know the system flows well with minimal (measured) backpressure, but I've never actually heard my exhaust at WOT without it being filtered through a helmet and a lot of wind noise.
The car is far from perfect, but I'm finding I'm still having to look at smaller and smaller items to remove weight or make handling improvements. (A first world problem, and I am not complaining.
)
) worked very well, and survived the abuse. The car was very well balanced, with just a hint of controlled oversteer which helped rotate the car around the tight corners. I've owned this car for decades, and was never able until just recently to flick the car back and forth through a slalom environment like it will do now. I did experience a bit of tail wagging under heavy braking, but I think I can clean that up with some geometry tweaks to the rear toe rods. I'm suspecting I'm getting a touch of rear toe changes under braking, so I'll do some measuring of things to see what I need to do to rectify this.Had an enjoyable time mixing it up on the track with a guy in a new 911. A very pleasant guy, after that first session he stopped over where I was parked and he complimented me on the car's performance, and was curious how my antique (my label, not his) handled that well. We had an enjoyable discussion.
One other item. One of the spectators stopped by and complimented me on how my car sounded. I thanked him for going to the effort to walk over to say that. I didn't bother him with details, but I was happy that my efforts fabricating the mufflers and resonator paid off. I know the system flows well with minimal (measured) backpressure, but I've never actually heard my exhaust at WOT without it being filtered through a helmet and a lot of wind noise.
The car is far from perfect, but I'm finding I'm still having to look at smaller and smaller items to remove weight or make handling improvements. (A first world problem, and I am not complaining.
)
phantomjock
Well-known member
From your track day analysis - sounds like you won't be needing the rear bar. Less weight, fewer items to check off the "smaller" list.
Cheers - Jim
Cheers - Jim
