FE1 Springs Auto VS Manual
Thread Starter
Drifting
Joined: Jul 2007
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From: Washington
FE1 Springs Auto VS Manual
Anyone know why there are different part numbers for auto and manual FE1 leaf springs? Specifically the front spring. Is it fitment or just spring rate?
Last edited by TRSCobra; May 30, 2020 at 08:08 PM.
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Spring rate, with the Auto having a little more tension for the added weight of the trans and torque converter during weight transfer during braking (so the front end does not dip too low to cause hook steering).
As for Fe1 and Fe3 trans springs on a balanced system, the Fe1's work better if you find your self gliding through corners, while the Fe3's do require forward braking weight transfer to get the front end to grip correctly into the apex isntead.
So really, if you have a manual, and adding a super charger with about 100lb in the front added, here is where you would want to swap from the manual to auto front trans spring. If auto and running a Fe1 auto, then may want to step up to a FE3 manual front trans spring instead.
As for Fe1 and Fe3 trans springs on a balanced system, the Fe1's work better if you find your self gliding through corners, while the Fe3's do require forward braking weight transfer to get the front end to grip correctly into the apex isntead.
So really, if you have a manual, and adding a super charger with about 100lb in the front added, here is where you would want to swap from the manual to auto front trans spring. If auto and running a Fe1 auto, then may want to step up to a FE3 manual front trans spring instead.
Thread Starter
Drifting
Joined: Jul 2007
Posts: 1,339
Likes: 245
From: Washington
Spring rate, with the Auto having a little more tension for the added weight of the trans and torque converter during weight transfer during braking (so the front end does not dip too low to cause hook steering).
As for Fe1 and Fe3 trans springs on a balanced system, the Fe1's work better if you find your self gliding through corners, while the Fe3's do require forward braking weight transfer to get the front end to grip correctly into the apex isntead.
So really, if you have a manual, and adding a super charger with about 100lb in the front added, here is where you would want to swap from the manual to auto front trans spring. If auto and running a Fe1 auto, then may want to step up to a FE3 manual front trans spring instead.
As for Fe1 and Fe3 trans springs on a balanced system, the Fe1's work better if you find your self gliding through corners, while the Fe3's do require forward braking weight transfer to get the front end to grip correctly into the apex isntead.
So really, if you have a manual, and adding a super charger with about 100lb in the front added, here is where you would want to swap from the manual to auto front trans spring. If auto and running a Fe1 auto, then may want to step up to a FE3 manual front trans spring instead.
Thanks for clearing it up! I'm just looking for the lowest spring rate for a drag racing application. Manual FE1 sounds like the ticket!
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C6 of Year Finalist (performance mods) 2019
BTW, For exact spring rate specs, try contacting Jim Mero who was the Corvette suspension guru for the C6.
Thread Starter
Drifting
Joined: Jul 2007
Posts: 1,339
Likes: 245
From: Washington
I understand removing the front sway bar to reduce weight, but fail to see an advantage in softer front springs. I'm just questioning what difference does the front spring rate make for drag racing?
BTW, For exact spring rate specs, try contacting Jim Mero who was the Corvette suspension guru for the C6.
BTW, For exact spring rate specs, try contacting Jim Mero who was the Corvette suspension guru for the C6.
http://www.cachassisworks.com/Attach...1-226_drag.pdf
Race Director
Joined: Sep 2007
Posts: 16,557
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
A softer spring will transfer weight to the rear better. My car is a Z06, so a 420lb/in Manual FE1 spring is a good bit lighter than my stock spring. Figured a used take off spring would be cheap to try out anyways. Here's where I'm getting my information:
http://www.cachassisworks.com/Attach...1-226_drag.pdf
http://www.cachassisworks.com/Attach...1-226_drag.pdf
If you're currently having traction issues on launch, other than controlling the rate of power application, what else have you changed from bone stock?
Thread Starter
Drifting
Joined: Jul 2007
Posts: 1,339
Likes: 245
From: Washington
I suspected you had looked at that type of information. Unfortunately, that is entirely based on use of adjustable coil springs with adjustable shocks, which wouldn't be on your car when retaining a leaf spring. A lighter rate front leaf spring can increase the vertical travel, but without adjustable shocks, the weight transfer can bounce back and forth both on the initial launch and during shifts. The biggest concern from my point of view, would be the possibility of lifting the front too high during the final shift at speed and the bounce on the rebound.
If you're currently having traction issues on launch, other than controlling the rate of power application, what else have you changed from bone stock?
If you're currently having traction issues on launch, other than controlling the rate of power application, what else have you changed from bone stock?
