North American Turbocoupe Organization

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I am looking at some different springs to put in the 88 TC and I have some questions on spring rates. I noticed the ford "B" springs have a rate listed as 425/530 for fronts and 200-300 for rears, these are not listed as progressive so what gives? Also the "C" springs list the fronts as straight 600 and the rears as 200-300, same question on rates. I think I found some that are a nice compromise in the BMR springs with fronts at 535 and rears at 235. What do you all think on these, I already have some MM rear control arms with adjustable spring perches for the install. Does anyone have the factory TC spring rates for comparison? Thanks
So I have an update on the BMR springs that I was looking at. I emailed them and asked about the load ratings on both the front and back springs to compare to a TC and a Mustang. Here is what they replied about the 79-04 Mustang spring load ratings. On the front springs the load rating is 1800lbs @ 9" and for the rear springs they are only 580lbs @ 8.7". It would seem the fronts are about perfect for our cars, but the rears are too soft a load rating. Best part is, the fronts are available as a pair for around $100. The rears as they are too weak, I emailed coilssprings.com for a quote, which they gave me with stock TC rear springs with a 1" drop and a %10 increase in rate they come out to be $276 a pair. So for springs that are TC specific in the rear and aftermarket in the front, looking at $376, ouch. I will probably get the BMR fronts and keep thinking of a good route for the rears. Just thought I would pass along the rate info on these.
I guess my question would be why not use the Moog replacement springs that are available ?
Stock replacement springs are available for like $50-60 a pair, i just recently put some in mine.
Like many on here, I was looking to lower the TC about an inch all around and the stock springs replacements would be just that, stock springs. I did some research here and found the post about different foxbody spring rates that listed some older LTD springs. I checked out both the Moog CC821 and CC823 springs, they are both a variable rate, but have a higher load rating than Mustang springs and a higher "listed" spring rate than stock TC springs. I did order a set of the CC821 which show a lower installed height than stock. Of course the car is stored for winter and I am not able to get into the change till spring. When I do the swap, I will take many pics of before and after to compare the difference. I have some stock 04 Mustang GT springs in the back right now, but as they have a lower load rating, it does not like any extra weight or bumps, this is with some machined 3/4" spacers in there as well. I was simply trying to find some easily bought springs that more closely match the load ratings of our TC, but are lower and a little stiffer. More to follow when the snow is gone.
Sorry didn't mean to be rude, just trying to help. There are a lot of posts of people cutting a loop off to lower, and at $50 a pair for new springs why not just try it
(02-02-2020, 09:49 PM)Kuch Wrote: [ -> ]Like many on here, I was looking to lower the TC about an inch all around and the stock springs replacements would be just that, stock springs. I did some research here and found the post about different foxbody spring rates that listed some older LTD springs. I checked out both the Moog CC821 and CC823 springs, they are both a variable rate, but have a higher load rating than Mustang springs and a higher "listed" spring rate than stock TC springs. I did order a set of the CC821 which show a lower installed height than stock. Of course the car is stored for winter and I am not able to get into the change till spring. When I do the swap, I will take many pics of before and after to compare the difference. I have some stock 04 Mustang GT springs in the back right now, but as they have a lower load rating, it does not like any extra weight or bumps, this is with some machined 3/4" spacers in there as well. I was simply trying to find some easily bought springs that more closely match the load ratings of our TC, but are lower and a little stiffer. More to follow when the snow is gone.
Thank you for sharing the Moog part numbers.  I am going to try out the CC821 when I swap out the rear control arms in the next couple weeks.  I bought the lower CHE control arms with the adjustable height to bring the car back to OEM ride height until I am ready to lower the front.  If I lower my car it will only be 1" because of the horrendous New England roads.
(02-15-2020, 08:54 PM)RC Martin Wrote: [ -> ]Sorry didn't mean to be rude, just trying to help.  There are a lot of posts of people cutting a loop off to lower, and at $50 a pair for new springs why not just try it
No worries RC, it was more my fault for not explaining in the first post. I tried cutting some off of the rear stock springs already and was not happy with it. With the style of the spring, when cut it will not sit flat like stock. I didn't like that which lead me to look at different replacement springs that will drop right in.
I have the BBK lowering springs for a SN95 and they lowered my car and it has a great stance and great handling. I have a 275/40/17 tire in rear w/no rubbing. 255/40/17 up front w/no rubbing unless I hit a monster hold or bump at speed.... I don't know how to post pics up here yet but I could get some up if your interested
347BIRD Wrote:I have the BBK lowering springs for a SN95 and they lowered my car and it has a great stance and great handling. I have a 275/40/17 tire in rear w/no rubbing. 255/40/17 up front w/no rubbing unless I hit a monster hold or bump at speed.... I don't know how to post pics up here yet but I could get some up if your interested
 I would love to see a pic, I have been looking at the 10th anniversary wheels for my 88 also. did you remove the quad shocks out back?
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