SPRING RATES & DROPS: ALL IN ONE THREAD!!

[5.0_SD]

How much of a drop do the GT350 springs offer on a GT?

I will tell you all right now, I like the GT350R front springs with BMR handling springs in rear as far as ride goes...what I don't like is that the rear is now lower than the front (and yes I did the spacer thing and all I was told to). I am seriously considering getting the revised BMR front handling springs to get more drop in front to match the back. The whole point of GT3350R front BMR rear was to have the spring rates close...so am I thinking correctly here? (I hate that the back is lower!!!)

 

[dbegley]

Those spreadsheets are AWESOME. Thank you so much for taking your time to put those together.

 

[dbegley]

I had a similar problem when I did a lowering set up on my 68 GT350. I ended up cutting half a coil from the front springs to drop the front down about an inch. It leveled the car out.

 

[BradleyMac]

Great job in pulling all this spring rate info together. I wish I would have found this site before I ordered the springs I have sitting in my garage.

Does anyone have any hands on experience with the BMR Handling Springs with a spring rate of Front 300/Rear 980 (1.2" drop F / 0.50" drop R)?

I have a set of the BMR Handling springs but haven't installed them yet as I believe they will be too stiff relative to the current GTPP spring rates of Front 165/Rear 728. I really want the rake look which these springs provide, but in hind site think I should have gone with the BMR Performance springs which are a lot closer to the factory spring rates.

Anyone have experience with these stiffer BMR handling springs and wish to provide their opinions of same ie: are they stiff as hell and extremely noisy on rough pavement?

Cheers and thank you for any advice you can provide.

 

[BmacIL]

Great job in pulling all this spring rate info together. I wish I would have found this site before I ordered the springs I have sitting in my garage.

Does anyone have any hands on experience with the BMR Handling Springs with a spring rate of Front 300/Rear 980 (1.2" drop F / 0.50" drop R)?

I have a set of the BMR Handling springs but haven't installed them yet as I believe they will be too stiff relative to the current GTPP spring rates of Front 165/Rear 728. I really want the rake look which these springs provide, but in hind site think I should have gone with the BMR Performance springs which are a lot closer to the factory spring rates.

Anyone have experience with these stiffer BMR handling springs and wish to provide their opinions of same ie: are they stiff as hell and extremely noisy on rough pavement?

Cheers and thank you for any advice you can provide.

They're stiff, no getting around that. However, when controlled well, I don't find them harsh on anything but the worst surfaces. I have GT350R front springs, which aren't quite as stiff but are in the same ballpark, and the Handling rears. With Koni yellows, Steeda Pro Actions or the Bilstein HD shocks and struts, you can have a car that's firm and handles really well, but not too harsh for daily use. I drive mine every day.

 

[BradleyMac]

They're stiff, no getting around that. However, when controlled well, I don't find them harsh on anything but the worst surfaces. I have GT350R front springs, which aren't quite as stiff but are in the same ballpark, and the Handling rears. With Koni yellows, Steeda Pro Actions or the Bilstein HD shocks and struts, you can have a car that's firm and handles really well, but not too harsh for daily use. I drive mine every day.

Thx Bmac, I should have also noted that in the summer I drive this car daily (park it in the winter) but I don't track it. Without this spring rate spreadsheet I assumed that the term "handling" also inferred a little better ride, but after digesting all the info. on this site and spreadsheet, I clearly see that it really means these "handling" springs are meant for track & auto X not daily driving :doh::frusty::headbonk:

Next question is, would anyone be interested in purchasing these BMR Handling springs as I'm thinking the BMR Performance is the way I should go ... to keep close to factory but get the lowering rake I'd like. FYI, I'm in Canada.

 

[BmacIL]

Thx Bmac, I should have also noted that in the summer I drive this car daily (park it in the winter) but I don't track it. Without this spring rate spreadsheet I assumed that the term "handling" also inferred a little better ride, but after digesting all the info. on this site and spreadsheet, I clearly see that it really means these "handling" springs are meant for track & auto X not daily driving :doh::frusty::headbonk:

Next question is, would anyone be interested in purchasing these BMR Handling springs as I'm thinking the BMR Performance is the way I should go ... to keep close to factory but get the lowering rake I'd like. FYI, I'm in Canada.

Yes I would highly recommend the performance springs for what you want. You will love them.

 

[GTP]

I have the GT350 springs on my car, and while I have become used to them, I still find them too stiff for use as a daily driver. Bmac finds them acceptable up to harsh roads, but I find them acceptable only up to medium rough roads. My fiance refuses to ride in my car anymore.

[MENTION=26937]BradleyMac[/MENTION], I think you will like the BMR performance springs, just like your logic tells you. If you don't track your car, I don't see any reason to go any stiffer than these (or than Performance Pack springs).

 

[BradleyMac]

Thanks BMac and GTP, it's great to get your first hand experiences to verify my thoughts. Cheers and all the best.

I love this car and can't wait till next spring to get it back on the road. Last week it was 85F and this week we got our first dump of snow and it's 30F.

 

[Radiation Joe]

I have the GT350 springs on my car, and while I have become used to them, I still find them too stiff for use as a daily driver. Bmac finds them acceptable up to harsh roads, but I find them acceptable only up to medium rough roads. My fiance refuses to ride in my car anymore.

When I met my future wife my 3300 lb M3 had 500 lb springs in the front. She needed a sports bra to keep the mammaries in check. She never complained any significant amount. I suggest you make a new life decision.

 

[GTP]

Then I would refuse to ride in your car. I'd need a mouthguard and who knows what else.

I am going back to the stock springs in a couple of weeks. No, it's not a manhood issue for me. Your suggestion was not appreciated.
:cheers:

 

[Radiation Joe]

Then I would refuse to ride in your car. I'd need a mouthguard and who knows what else.

I am going back to the stock springs in a couple of weeks. No, it's not a manhood issue for me. Your suggestion was not appreciated.
:cheers:

Just trying to throw a little levity into the discussion. Usually, stiff springs only cause problems in slow speed situations like parking lots and speed bumps. If you spend a lot of time on the highway, stiff springs are very livable. The real problem for me and the Mrs. was railroad tracks at 25 to 30 mph. Everyone's situation is different.

Please enjoy your life with the future Mrs. GTP, regardless of spring choice.

 

[GTP]

I can deal with the occasional RR track or speed bump. It's long rough roads that kill it for me. Our street has evenly spaced seams and it needs repaved. The main drag where I work is the same. The rhythmic jarring is irritating.

I've decided to switch to the stiff setup for running a compressed track season, and the stock setup for the bulk of the year.

 

[GuardEcoBeast]

Why is there no ecoboost spring rates on the spreadsheet?

 

[dsp4848]

Why is there no ecoboost spring rates on the spreadsheet?

I haven't come across the factory spring rates of the Ecoboost springs (or V6 for that matter), so that's why there isn't any percentage to compare to. The boxes in the spreadsheet that say "0" are ones that I don't have specific info for. If the source/manufacturer of the springs didn't explicitly state rates for a particular model (i.e. Ecoboost), I didn't include it in that model's spreadsheet. Just didn't want to make any assumptions when putting the sheet together. I'll try to go through the spreadsheet this weekend and see if there's anything I can update - I haven't updated it in a while.