BuckeyeDemon 211 Report post Posted October 2, 2011 I guess the springs are 560 lbs. The other set is 750 lbs. Just wondering if it is my springs cause I cant see them giving me bad advice after I gave him my specs. wow. 750 lbs for the 620's? i see numbers all over the map for those things. NPD claimed the standard replacement spring (small block) was rated at 282 lbs/in and the heavy duty spring (i.e. mach 1) was rated at 428 lbs/in. if you wouldn't mind, when/if you add the sway bar/springs do it one change at a time so you can test the effect of each alteration. i unfortunately don't have that luxury so i'll never know the before/after difference. good luck. i hope you end up with something that makes you happy. Quote Share this post Link to post Share on other sites
gsxrken 21 Report post Posted October 2, 2011 Outright "handling" is mostly due to tires and how the suspension geometry puts that tire on the road. Feel, on the other hand, is much harder to measure but you know (like you do) when you're not happy with it. I'd suggest an export brace to start with, as I don't see any mention of that. That is the biggest bang for the buck out there in terms of chassis improvement. Secondly, you mention "floating" - I'd say that is shocks and the Edelbrock's are a soft shock. As said elsewhere on this board, Koni's or Bilsteins from Maier are really the only serious shocks for these cars if you are going to push them. Floating can be too much air getting under the car- lowering helps here. Sway bars won't help floating, but if the the body is swaying from side to side on transitions, more sway bar or spring rate can address. A rear sway bar on our cars can flatten the car out below let's say 7/10s driving intensity, but bring the ass around too suddenly with oversteer when you go all out. And an alignment to OT's specs will do wonders in feel as well. Quote Share this post Link to post Share on other sites
panteramatt 1 Report post Posted October 2, 2011 Yea I just talked to john from opentracker and he told me I really need the alignment to his specs. Im going to cut the springs a little cause the car never lowered when I put them on and then get the alignment done. If im not satisfied after that, Im going with a new swaybar. Quote Share this post Link to post Share on other sites
panteramatt 1 Report post Posted October 2, 2011 Yes it has the stock export brace on it. What size swaybar should I go, 1 or 1 1/8". John says they all run the bigger one. Quote Share this post Link to post Share on other sites
69gmachine 15 Report post Posted October 2, 2011 It's a little pricey, but the 1 1/8 hollow bar from Cobra Automotive works wonderfully and doesn't add unnecessary weight to the front end. There are other things you can do to make the rear handle better if you're willing to do some modifications. I built my own rear springs starting with Mustang II springs because they're shorter. I added an extra leaf to beef them up, and drilled a new locating pin hole to place the rear end at the correct distance. Then I welded in sliders in place of the rear shackles. They keep the springs from binding when in compression so the rate stays linear. They also lower the car about an inch and a half. My car stays exceptionally flat in the turns (although I have a coil over front set up so it's not a fair comparison to roller perches). I make full use of the side bolsters in my seats and a 4 point harness. Quote Share this post Link to post Share on other sites
Angel 24 Report post Posted October 2, 2011 I went with th 1 1/8" front bar. If you lower the car enough, you will need shorter end links to keep the bar from hitting the frame. I drove mine around for a while like that and around hard turns, you can feel the back end lift on the inside wheel while the front stayed flat. If I had sfc, maybe this wouldnt have been so noticeable. But since I didnt, I decided to add a 7/8" rear bar from addco. That definitely matched the rear to the front. I do agree with gsxrken about the potential to spin out if you push it too hard. Quote Share this post Link to post Share on other sites
1969 Mach1 14 Report post Posted October 3, 2011 panteramatt: Measure the wire diameter of the spring. If it measures close to 0.520" the springs will have a much lower spring rate than 520 lb./inch. They will be too soft for a 1969 351w Mustang if you are trying to get some handling performance from it. Even if they are 520 lb./inch that is too soft. Several other things will help as well, sway bars, export brace and monte carlo bar, etc. If you are not sure what you need I would contact Maier Racing. I am running stuff from Mustangs Plus, front springs are 720's rated at I think 600 lb./inch, 5 leaf mid-eye rear springs rated at 200 lb./inch, 1" dia. front and OEM rear sway bar, and urethane bushings everywhere. I am happy with it. I prefer Maier Racings's stuff primarily because they have more knowledge in this area, but these springs came with my car. Quote Share this post Link to post Share on other sites
Black_69_FB 49 Report post Posted October 7, 2011 Yes it has the stock export brace on it. When you say 'stock export brace' do you mean the factory firewall to shock tower braces, like these?: http://coloradomustang.com/ShowItem/100045%20Mustang%20Firewall%20To%20Shock%20Tower%20Brace%201969%20-%201970.aspx If so, you'll want a true one-piece export brace like gsxrken was saying earlier in the thread, like so: http://www.lovemustangs.com/_a_Images%20used%20for%20forums/MM0205-Install_Monte_Carlo_Bar_pg01.jpg Quote Share this post Link to post Share on other sites
panteramatt 1 Report post Posted October 7, 2011 Yea mine are those stock ones. Im replacing then soon anyway along with a Monte carlo bar and subframe connectors. Quote Share this post Link to post Share on other sites