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Blk Nsty

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Discussion starter · #1 · (Edited)
Just received my Tokico D Spec Shocks/Struts in the mail yesterday. Now I'm stuck between what springs I should order to go along with them... I love drag racing, but also want a little bit of a drop... I know, not a good combination. I've been looking at Cobra Jet Drag Springs, Eibach Drag Launch Springs, and Eibach Pro Kit Springs.

The spring rates are as followed:
Cobra Jet: Unknown, but must be low considering they are used on the Cobra Jet Mustangs themselves.
Eibach Drag Launch: 148 lb/in Front, 143 lb/in in the left rear and 114-285 lb/in in the right rear.
Eibach Pro Kit: 171-281 lb/in Front, 180 Rear.

My question is if I go with the Eibach Pro Kit for the little bit of a drop, will I notice a huge difference in the spring rates with weight transfer? I know if I want to lower my 60' times I need the lowest spring rate as possible really for the best weight transfer. I just need some opinions on this matter so I can hurry up and order springs already, I'm dying to put these parts on.

Also a side note, has anyone ever used or seen a car with Cobra Jet Drag Springs? I know Brenspeed carries two sets, a 2008 Drag Spring Kit which is applicable with all 05-10 GTs and a 2010 Drag Spring Kit that's applicable with all 05-10 GTs and the 2010 kit says it lowers the car 1.9" Front and 2.5" Rear. Would this be something worth trying? I know it's a big drop, but I don't know if it'd be worth it with 15x10 Drag Star wheels and a 325 Mickey Thompson drag radial out back and skinnies up front.

One last question, does anyone know the spring rates of BMR lowering springs? I've considered those as well, I just can't seem to find the spring rates.

Thanks.
 
#2 ·
Blk Nsty said:
Just received my Tokico D Spec Shocks/Struts in the mail yesterday. Now I'm stuck between what springs I should order to go along with them... I love drag racing, but also want a little bit of a drop... I know, not a good combination. I've been looking at Cobra Jet Drag Springs, Eibach Drag Launch Springs, and Eibach Pro Kit Springs.

The spring rates are as followed:
Cobra Jet: Unknown, but must be low considering they are used on the Cobra Jet Mustangs themselves.
Eibach Drag Launch: 148 lb/in Front, 143 lb/in in the left rear and 114-285 lb/in in the right rear.
Eibach Pro Kit: 171-281 lb/in Front, 180 Rear.

My question is if I go with the Eibach Pro Kit for the little bit of a drop, will I notice a huge difference in the spring rates with weight transfer? I know if I want to lower my 60' times I need the lowest spring rate as possible really for the best weight transfer. I just need some opinions on this matter so I can hurry up and order springs already, I'm dying to put these parts on.

Also a side note, has anyone ever used or seen a car with Cobra Jet Drag Springs? I know Brenspeed carries two sets, a 2008 Drag Spring Kit which is applicable with all 05-10 GTs and a 2010 Drag Spring Kit that's applicable with all 05-10 GTs and the 2010 kit says it lowers the car 1.9" Front and 2.5" Rear. Would this be something worth trying? I know it's a big drop, but I don't know if it'd be worth it with 15x10 Drag Star wheels and a 325 Mickey Thompson drag radial out back and skinnies up front.

One last question, does anyone know the spring rates of BMR lowering springs? I've considered those as well, I just can't seem to find the spring rates.

Thanks.
Click to expand...
IIRC the BMR springs are in the 160-170 lb/in rate which is a little more ideal for keeping the car off bump stops than some of those drop + super soft spring rate springs have. Bumpstops are a bad place for ANY car to play, handling or drag racing!

I am no super drag racing expert but the BMR springs are barely 30 lbs/in stiffer than stock. In the grand scheme of things that isn't much. Even the Steeda Sport rears at 175 lbs/in are not THAT stiff. I wouldn't think that mild increase is going to change the launch characteristics that much. I would be more worried about control arm angles at that point than the spring rates. BMR is a solid company and I trust their more dedicated to drag racing and Domestic cars approach to Eibachs more handling oriented and "as many cars as possible" stance for product development.

If Ford follows the same trend they have followed in the past with "aftermarket" springs, the Cobra Jet springs could vary well be the Eibach drag springs, but don't quote me on that, just pure speculation! I would also be hesitant to run those really big drop Cobra Jet springs. My car with a 1.25" drop is about half an inch from contacting the bumpstops and I am sure I hit them with alarming regularity in daily driving. A 2.5" drop in the rear would have the rear axle riding on the bumpstops which adds spring rate which is bad for launching and the extreme progressive nature (to nearly full solid towards the end) of the bumpstops makes for some radical bits of ass chasing face when pushed hard in a handling environment. Doesn't the Cobra Jet have a 9" out back? Would that have better axle clearance to the frame rails than our 8.8" on the wheel end of the axle? I wouldn't think so, it makes me wonder what about the Cobra Jet accomidates such a low stance!
 
Discussion starter · #3 ·
Thanks for info. I think I'm wanting to go with BMR. I was also looking at Steeda because they're spring rates weren't terrible. It sounds like those are my best two choices when it comes to a drag spring with a mild drop. I'm kind of leaning towards BMR though. I'm just really curious how the weight transfer will be with those. Is 170 ft/in compared to 140 ft/in spring rates a huge difference? You wouldn't think so, but I have no clue.

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#4 ·
Blk Nsty said:
Thanks for info. I think I'm wanting to go with BMR. I was also looking at Steeda because they're spring rates weren't terrible. It sounds like those are my best two choices when it comes to a drag spring with a mild drop. I'm kind of leaning towards BMR though. I'm just really curious how the weight transfer will be with those. Is 170 ft/in compared to 140 ft/in spring rates a huge difference? You wouldn't think so, but I have no clue.

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Click to expand...
Probably a good question to send to Kelly at BMR. I don't think 30 lbs/in is a huge difference, I suppose it is 21% stiffer than stock but isn't going to make the car unlaunchable. I would say that if you address the geometry change issues with LCA relocation brackets that you shouldn't have any issues getting the forward bite you need to launch at the strip.

The Steeda Sports are aimed more towards the handling crowd than the drag racing crowd which explains their stiffer spring rates which in the grand scheme of things are not that stiff either. Cars in the Grand Am Continental Tire Sports Car Challenge are running 600 lb/in front rates and 300 lb/in rear rates or around that on most race tracks. Many an autocross cars are pushing even higher rates than that when they have good coilovers. My buddy will be running 800lb/in front and 900 lb/in rear rates on his Evo IX SE on his coilovers.
 
Discussion starter · #7 ·
Oh, and when I start buying those suspension parts I will be getting relocation brackets and all that good stuff.UCA with brackets, LCA with brackets, panhard bar, rear sway bar, front sway bar delete. All the things needed for a nice drag set up.

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Discussion starter · #8 ·
I'm not going to lie, those Tien springs look like a good idea. Do you have any pictures of your car you can post for me? I would love to see the drop.

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#9 ·
I don't have many side views pre lowered because it had such a rediculous 4x4 stance
Image

Image

Image

Here you can still see the weight transfer to the rear under launch
Image

Not the best comparison but this is my buddys car launching on his stock springs, weight transfer looks almost the same
Image
 
#10 ·
Blk Nsty said:
Oh, and when I start buying those suspension parts I will be getting relocation brackets and all that good stuff.UCA with brackets, LCA with brackets, panhard bar, rear sway bar, front sway bar delete. All the things needed for a nice drag set up.

You had better add some good camber plates, if you go more than a 1" drop in the front. I have Steeda Sports and am at the limit of adjustments with camber bolts. Also consider having to buy some aftermarket, shorter bumpstops (I have the FRPP ones), or cutting your OEM ones. I just don't see how a low spring rate, combined with a 1.5 " drop or more, can avoid bottoming out, especially when driven on the streets.
Click to expand...
 
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Discussion starter · #11 ·
I'm not wanting a low spring rate to prevent bottoming out. I'm wanting low spring rates for drag racing and weight transfer, but I'm looking for a happy medium to have a stance and be able to get good 60' times.

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#12 ·
I'll make it short and sweet.

If you want to be able to drag race the car effectively, and have a nice drop, the BMR-SP009 is THE set of springs that will enable you to do so. I cannot even begin to list how many sets of springs we have replaced over the years due to a customer using the "other" springs, and not getting the results that they are after.

Our spring rates are 165F / 160R - Linear working rates.

We also utilize the hourglass rear spring design for increased traction / reduced wheel hop.

If you have any other questions or concerns, please let me know.

Thanks!
 
#14 ·
I'll be honest— I don't know **** about drag setups, but I do know that if both Kelly and Whiskey say to go BMR, you damn well better go with BMR.

:yes :p
 
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