Best frt coil spring to lower frt

[BandBSTANGS 15]

Who makes the best frt coil spring to lower the frt of my 70 coupe. I would like to lower the frt 1-1/12 inches.

I'm looking for a better controlled ride and the lowered look without jarring my fillings out.

Car has a 351c, would it be to my advantage to get spring for a small block car as most spring info puts the Cleveland

with big block spring rate.

Anyone have photos of their car with lowering springs that haven't been cut to help drop car?

[BandBSTANGS 15]

Anyone?

 

Should I use spring from NPD or Eibach, or Global west?

[1969_Mach1 333]

Its not an easy topic.  Ride quality is very subjective.  Most soft aftermarket springs, such as those from NPD, Global West, and Eibach have rates in the 550 lb./in range.  That is higher than a big block spring rate.  I don't think a small block spring will work very well for those requirements.  The suspension might bottom out a lot.  I'm sure there are other members here with more knowledge than I have in this area. 

[Rsmach1 71]

I used a set of 1" drop 620# coils with a 351w, to me they are by no means bone jarring.

 

Note, I also run a 60 series tire on 15" wheels, if you have 17s or 18s with a low pro tire it will be stiffer.

[970fizz 19]

I run a grab-a-track 620 with one full coil cut. ( about 2.5 lower). But still rides good.

[larryc94 38]

I'm using grab-a-track 620's (which I think are like 560 lb) for a 65-66 uncut with a 3/4" poly spacer.  I have the Shelby drop with roller perches and KYB low pressure shocks.

 

 Ride is excellent, eats up the patched up roads we have in the NE after winter.  Ride is much improved over the stock Mach I suspension.

  

Handling has been improved greatly.  The rear is Scott Drake 4.5 mid eye with 1" blocks. Was afraid of using reverse eye's for fear of being too low and not being able to fix it having to either replace or re arc, if the rear becomes low I can always remove the blocks to raise it.

 

The stance is exactly what I wanted.  Mixing different suspension components together is a crap shoot. I took a chance using the 65-66 springs in a 70.  I have 215/70-14 tires.

 

I didn't want to cut the springs and alter there rate which seems to be popular.  The 65-66 springs are 1" shorter than the 70.  I'm surprised I haven't found some else going this route,  worked well for me it's been 1 1/2 years since done

[larryc94 38]

I'm using grab-a-track 620's (which I think are like 560 lb) for a 65-66 uncut with a 3/4" poly spacer.  I have the Shelby drop with roller perches and KYB low pressure shocks.

 

 Ride is excellent, eats up the patched up roads we have in the NE after winter.  Ride is much improved over the stock Mach I suspension.

  

Handling has been improved greatly.  The rear is Scott Drake 4.5 mid eye with 1" blocks. Was afraid of using reverse eye's for fear of being too low and not being able to fix it having to either replace or re arc, if the rear becomes low I can always remove the blocks to raise it.

 

The stance is exactly what I wanted.  Mixing different suspension components together is a crap shoot. I took a chance using the 65-66 springs in a 70.  I have 215/70-14 tires.

 

I didn't want to cut the springs and alter there rate which seems to be popular.  The 65-66 springs are 1" shorter than the 70.  I'm surprised I haven't found some else going this route,  worked well for me it's been 1 1/2 years since done

[barnett468 418]

Buy a spring that lists the rate . . the stock springs are around 280 the NPD 480 or 520 springs won't be jarring but they will be noticeably firmer . . you need good shocks to compensate for the higher rate . . the modified biksteins are popular . . the white kyb gas shocks are decent for the price.

[TexasEd 188]

I'm using grab-a-track 620's (which I think are like 560 lb) for a 65-66 uncut with a 3/4" poly spacer.  I have the Shelby drop with roller perches and KYB low pressure shocks.

 

 Ride is excellent, eats up the patched up roads we have in the NE after winter.  Ride is much improved over the stock Mach I suspension.

  

Handling has been improved greatly.  The rear is Scott Drake 4.5 mid eye with 1" blocks. Was afraid of using reverse eye's for fear of being too low and not being able to fix it having to either replace or re arc, if the rear becomes low I can always remove the blocks to raise it.

 

The stance is exactly what I wanted.  Mixing different suspension components together is a crap shoot. I took a chance using the 65-66 springs in a 70.  I have 215/70-14 tires.

 

I didn't want to cut the springs and alter there rate which seems to be popular.  The 65-66 springs are 1" shorter than the 70.  I'm surprised I haven't found some else going this route,  worked well for me it's been 1 1/2 years since done

 

 

This is basically what I'm doing based on advice from OpenTracker.

I bought the complete suspension set from him and have the front end installed.  As soon as I get the steering back in I'll put it on the ground.

[BandBSTANGS 15]

Spoke with "John?" at OpenTracker and we discussed my car and my objective and he gave a couple of suggestions.

 

1. Use stock big block springs, mark the 1st 2 coils of the spring at 1/4 turns on spring and start at either a 1/2 or full coil cut off until desired ride height is reached. This will upgrade to a stiffer spring with cut off done with out reaching the stiffness of the lowering 620 springs.

 

2 The other option was to move the lower perch out on lower control arm approx. 1 inch and use stock small block spring and trim as needed to obtain ride height. This is a track/road race modification that he said would help with handling.

 

Both methods will lower car, firm up the ride without having a jarring ride per John. Will occasionally go to the dragstrip and John stated that this will also allow the frt suspension to transfer weight vs the 620 spring which wont allow weight transfer.

 

Has anybody used either method?

[TexasEd 188]

No, but John is a straight shooter.

[1969_Mach1 333]

You should probably verify your option #2.  That might be lower the upper control arm 1" which is a very common upgrade.  Most everybody does it.  Moving the location of the lower spring perch might mess up the alignment for the coil spring.  Why not lower the upper control arm 1", then try the big block springs?  You wouldn't have to trim them as much.  In my opinion, I think the suspension will bottom out more often using the stock small block springs with the car lowered.

[TexasEd 188]

Yeah,  I lowered the UPPER control Arm 1".  I also used the 620# grab a track springs in my small block car which are stiffer and shorter than stock.

 

This is common and what I have done.  I think your #2 option is typed wrong.

[Opentracker 4]

 

2 The other option was to move the spring perch out on upper control arm approx. 1 inch and use stock small block spring and trim as needed to obtain ride height. This is a track/road race modification that he said would help with handling.

 

 

I corrected the post a little.

 

We often move the spring perch out on the upper arm closer to the ball joint to get a better motion ratio. it doesn't upset the angle of the coil and it does enhance the handling of the cars. The " one inch perch move " as we call it adds about 125lbs to the spring rate and raises the car 1/2". I suggested using the small block spring with the perch move because it would raise the spring rate to something close to the stock big block spring. My thinking is that a 450lb-ish spring would work good for this application.

 

BandBSTANGS  wants to do some drag racing with the car so I recommended not using the 600# spring so the car would leave the line a little better. He wants good handling on the street too so the #1 or #2 option would do that for him without being too stiff.

[barnett468 418]

Spoke with "John?" at OpenTracker and we discussed my car and my objective and he gave a couple of suggestions.

 

1. Use stock big block springs, mark the 1st 2 coils of the spring at 1/4 turns on spring and start at either a 1/2 or full coil cut off until desired ride height is reached. This will upgrade to a stiffer spring with cut off done with out reaching the stiffness of the lowering 620 springs.

 

2 The other option was to move the lower perch out on lower control arm approx. 1 inch and use stock small block spring and trim as needed to obtain ride height. This is a track/road race modification that he said would help with handling.

 

Both methods will lower car, firm up the ride without having a jarring ride per John. Will occasionally go to the dragstrip and John stated that this will also allow the frt suspension to transfer weight vs the 620 spring which wont allow weight transfer.

 

Has anybody used either method?

Read my post

 

Also install a 7/8 front sway bar with urethane bushings

 

If you plan on doing aggressive cornering, lower the front upper suspension arm 1" or buy the TCP upper 1" lowering arms

[BandBSTANGS 15]

_{SHELBY DROP HAS ALREADY BEEN DONE ON CAR, CAR HAS BEEN ALIGNED TO OPENTRACER ALIGNMENT SPECS.}

 

_{(THANKS JOHN FOR CHIMING IN AND CORRECTING MY MIS INFORMATION ON OUR CONVERSATION!)}

 

_{CAR WILL BE A FUN STREET DRIVER WITH WITH A WARMED OVER CLEVELAND.}

 

_{NOT LOOKING FOR A ROAD RACE VEHICLE, BUT A DECENT HANDLING CAR WITH THE LOWERED STANCE THAT I WOULD LIKE TO HAVE ( GOOGLE TERALINGUA sp? MUSTANG AND LOOK FOR THE 1970 MUSTANG )}

 

_{THIS IS SORT OF THE STANCE AND DIRECTION THAT I WOULD LIKE TO ACHIEVE}

[barnett468 418]

_{SHELBY DROP HAS ALREADY BEEN DONE ON CAR, CAR HAS BEEN ALIGNED TO OPENTRACER ALIGNMENT SPECS.}

 

_{(THANKS JOHN FOR CHIMING IN AND CORRECTING MY MIS INFORMATION ON OUR CONVERSATION!)}

 

_{CAR WILL BE A FUN STREET DRIVER WITH WITH A WARMED OVER CLEVELAND.}

 

_{NOT LOOKING FOR A ROAD RACE VEHICLE, BUT A DECENT HANDLING CAR WITH THE LOWERED STANCE THAT I WOULD LIKE TO HAVE ( GOOGLE TERALINGUA sp? MUSTANG AND LOOK FOR THE 1970 MUSTANG )}

 

_{THIS IS SORT OF THE STANCE AND DIRECTION THAT I WOULD LIKE TO ACHIEVE}

The spring rates I suggested will make it firm but not harsh . . 620 springs will make it harsh . . rear springs stiffer than 145 will make it pretty firm . . any of the shocks are good.

 

If your roads have a fairly big crown it is best to stagger the alignment . . I often use the specs below . . using more than 3 degrees of caster on a street car is excessive . . using more than .4 degrees not camber will increase tire wear especially on wide tires . . using less than 3/16" of toe in can cause your tires to be toed out at freeway speeds.

 

O.3 to 0.4 degrees of negative camber

 

2.5 to 3 degrees of positive caster.

 

3/16" to 1/4" of toe in