I posted this on another board so don't be surprised if you read it twice.... My '36 coupe has been on the road now for about 11 years and has never let me down even on a 4,000+ mile trip to bonneville However in the last year or so the front end has dropped significantly. Now the front tires rub when I make a hard turn and I can see evidence of the oil pan introducing itself to pavement. This summer I installed 500lbs coil overs in the front to see if that would raise it up. no change and they are cranked up to max. There is no evidence of any faults in the mustang II IFS after a close inspection. I had it up on a hoist to inspect it with a friend/mechanic/car builder extrodanaire. It has a 454BBC with A/C. I've taken off the road until I can figure out what is going on to make it sit so low. It can't settle this much after 10 years. Any thoughts?
Some pictures of your setup might help - particularly if you can get them while the car is on the hoist.
You lost me at coil over. If it was fine for years and it just started and new heavier springs didn't help, I'm going out on a limb and say something is bent/bending, or cracking. Get it up in the air and check it again. Oh yeah, your oil pan shouldn't be lower than the chassis.
Worn control arm bushings can cause a change in the ride height. With weight on the front suspension are the control arm shafts still centered in the bushings or are they eccentric? Was the drop gradual and only after the fact you noticed? Or did the car just seem to drop overnight? What were the original springs? And what are the new springs? *500lb/in spring means nothing without free/installed length. And what Blue One said.*
Yeah I know it would help with pics. Looked at on drive on and lift hoist. No evidence of anything bent or cracked. I'm not new at this game and nor is the other guy who looked at it. No dropped axles.....I like them and have owned a few dropped axle cars but not for this car.
I'm thinking the lower control arm bushings. With wear, the weight of the car will cantilever under the spring to the worn bushing. If the control arm was at a down angle it may be more level now, or if it was already level it may not be going at an up angle to the BJ. It doesn't take much wear to magnify the drop. Ball joint wear can also compound the problem if you have placed a lot of miles on them. Simply placing a jack on the control arm where the bushing is and pushing up may show a drastic change in ride height.
You are a man who knows his suspension! I'm going to check everything you recommend . I was looking for something more catastrophic like a crack or bend. I've always been suspicious of the ball joints
Nah. If the suspension has rubber bushings and they are ... Rubber, even in OEM applications, is pretty much starting to wear out by 30K miles. But keep an eye on the hardware too. Most aftermarket lower control arms just use one large bolt and two dinky bushings.
I gotta say I know this car and I know it gets driven... What springs were in it before? maybe get a new set of them?? and wait another 10+ years?
photo would help a lot,by give others a better understanding of the set up. coilover springs come in def sizes beside def rates,and they make spacers for them ,so say your max out on adjustment,means you got wrong spring size or no spacer if there is not some other thing going wrong.
Or the wrong coil over shock for your setup. Fit's MII suspension may not mean that it works perfectly with all MII suspension or it may be designed to set the ride height lower deliberately while not stating it in the paperwork. I'm with Mad Mike on this one as I'd be looking for worn parts including busings, bolts that run through them and the holes in the crossmember where the bolts run through along with checking the ball joints for wear. If it's and aftermarket front end a new pair of Moog ball joints doesn't cost very much. On the odd chance that the suspension is not worn to the point it is letting the car drop down like that could the body mounts or mounting points on the body be worn or sagging so that it is settling on the frame? If it was a Chevy AD truck with a V8 and automatic in it I'd already be thinking that the weight of the cab had caused the mounts to twist the frame rails. This might be something to check. Is the clearance between the floorboards and the frame rails the same as when you built the car?
There is no evidence of any faults in the mustang II IFS after a close inspection. I had it up on a hoist to inspect it with a friend/mechanic/car builder extrodanaire.
it could be the overall length of your coil over length not spring rate. the total length of the new combo could be shorter than your old mII set up. your using a MII spring where it was not intended. maybe it could be as simple as worn MII spring and the new set up being too short.
I'm by no means a suspension expert, but maybe I could attempt to give some input. When I did a mustang II ifs on my truck, the company (TCI) told me the springs would wear in after a 1000 miles or so giving a pretty significant drop (might of been an inch or two from what I can remember). Would it help if you got stiffer springs to compensate for all the wear/drop over the first couple thousand miles? But god damn if you have 500# springs that's pretty stiff already.
Yep, Its skidpan time! Did you check your original spring height when purchasing the new 500lb ones? 500lb springs at the worn spring height will keep your ride height the same... Oops! 50mercfan beat me to it.
Ive re-read these posts a couple times now and am seeing things that slipped by me the first time...Let me see if Ive got this right... You recently installed coil overs, but prior to that you were using stock (possibly V8) MII coil springs, correct? Since you found no signs of bending or cracking in the suspension, my thinking is that those stock coil springs that were intended to support a lightweight Ford smallblock, simply gave up the ghost supporting a big block Chevy for 11 years. Im not at all familiar with coilovers for a MII, do they come in different lengths for different installed heights, or are you just stuck with one length? If this is the case you may not have enough installed height to raise the front of the car with the heavy big block, even with 500# springs. Chances are that the coils/springs will support the weight, but you are just starting out too low initially.
What the hell does that mean? Man, the HAMB sure has changed since I've been a member . to the other guys, thanks. Some really good suggestions.
How should I know what it means to you,. They are your words. To me it means that everyone is telling you to check your suspension for wear and you've already done it. With emphasis added the level it was done to.
Without the pics of your setup ,there is no way of solving your problem. But after inspection and not finding anything yourself just says you missed something.
Can you explain your swap to coilovers? Ive got a 36 5w coupe with a 454 bbc (no ac) and running coilovers so were almost kin! I ran stock type springs initially but they sagged massively after a very short time on the road despite having sat fully loaded for a long time during the build. I know Id shortened the new springs a little too much and obviously the dynamic loads from driving killed them off in short order. Im wondering about your swap to coilovers as regular coilovers dont immediately fit into a MII application, both at the frame and especially at the a arm. At the a arm the original shock mount isnt substantial enough to carry the weight of the car the stock spring style have a large spring pad and the aftermarket type suitable for coilovers have a substantial mount. I have tubular a arms that were designed for stock springs but I removed those pads and made my own coilover lower mounts. My coilovers are the conical spring type such that the upper part (both spring and shock) mount to the frame as they do stock. In determining the position for the lower mount I initially used the weight of the car to establish the installed, compressed length of the coilover unit. This resulted in my lower mount being just above the tubular arm whereas the stock lower spring mount was just under the a arm, getting on for about 2 inches lower than where I mounted mine. Im therefore wondering whether your lower mount is too low and perhaps inadequate anyway? Also, Im unsure about your 500lb springs. Heidts list springs right upto 700. They used to recommend applications (small block / big block etc) but thats seemingly no longer in their catalogue. I recall the 700 was suggested for hemis w blowers etc and I think I went for 600s. Mine all worked superbly from the off and has been in use for a few years now. Hope this gives some food for thought. If youd like pics please pm me a regular email addy. Cheers Chris
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