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Discussion Starter #1
So I have 620lb 1" drops on the front, as well as a 1" arning drop.

My front tires are 235/45/17 (IIRC).

The front tires appear to be tucked up into the fender a little bit, so I assume they will rub if I'm turning and hit a bump. Which would be bad.

Should I get new coils (These are brand new) or just get a taller insulator. How come everyone complains they have to cut a coil, but mine seems to be sitting too low? I have an EFI 5.0, and no interior. Driving me nuts!
 

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Hey bud,

Another issue that might be bad, is those 620s combined with those low profile tires is going to make for one harsh ride with the tires subject to bruising. Stay away from potholes. This being stated, try bumping up the insulators. You don't mention what you have now, so, I can't offer a thickness, but, I have installed them to adjust side to side ride heights. I think they start at 1/2-1". You'll have to decide on how much you want to show.
Good Luck!
 

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That's a lot of tire. It is going to rub on full lock turns no matter what you do - especially on a lowered car. I have 215s on my moderately lowered 67 and they rub at full lock in reverse.
 

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Discussion Starter #4
Yeah, I was having problems finding a decent front tire size. The backs i went 245/40/17's.. They seem to fit much better. But I didn't want to go that wide in the front.

The ones I have now (insulators) seem really thin. 1/8" maybe, who knows! So maybe I'll grab new insulators.. Or if the price is close, just taller, light springs.. Problem is, I have 5 leafs in the rear.
 

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I run 245/45/17's on my 67. Lowered a inch and a half up front (arning drop and cut springs) and I do not rub at full lock with rolled fenders.
 

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Discussion Starter #8
I just took a quick glimpse at CJ's site.. I looked at their big block springs, and they say 300lbs.. That sounds more correct than our 620's.. Surely the 620's aren't twice as stiff as the big block springs?! I'm almost thinking of just buying the big block springs, but wondering if it will be all funky with 5 leafs in the rear.
 

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I just took a quick glimpse at CJ's site.. I looked at their big block springs, and they say 300lbs.. That sounds more correct than our 620's.. Surely the 620's aren't twice as stiff as the big block springs?! I'm almost thinking of just buying the big block springs, but wondering if it will be all funky with 5 leafs in the rear.
Just a reminder. A 600#(/in deflection) spring will deflect 1" before it supports 600#. A 300#(/in deflection) spring will deflect 2" before it supports 600#. I'm sure you know this, the ride height depends on the spring rate and the compressed length. The softer spring will be longer to start with in order to get the same ride height.

One point is cutting an inch off a 600# spring makes twice the difference as cutting an inch off a 300# spring.
 

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Discussion Starter #11
Yeah, I'm mildly rust on my springs but I get it. BUT, what I"m saying is, do we REALLY have 620lb springs if the Big block springs are 300lb?! Seems wildly excessive if that's true.
 

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Correct me if I'm wrong: 720 is 720 lb/in spring rate. 620 is 620 lb/in spring rate. The spring rate will go up as the spring is compressed. Obviousely when the coils are touching, completely compressed the spring rate is very high, almost infinite!
 

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Discussion Starter #15
Perhaps I'm not explaining myself correct. :D If the big blocks took 300lb/in springs, surely the aftermarket ones can't be 620lb/in.. That would be a MASSIVE increase. So I'm thinking 1 or the 2 have to be labelled wrong?
 

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Discussion Starter #17
Yup, mine appear to be lower and i can't figure out why. Everyone complains that even with drop springs they have to cut them..

So my tires are 25.3". I have a 1" drop, and 1" drop 620s.. Anyone have this exact same problem? Wish I could find a local place for some insulators so I didn't have to mail order them for this experiment. I'm afraid of going too stiff, and the car breaking apart. :D
 

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I can tell you I am running a 27.1'' tire on a 17x9 rim in the front. yeah, it sounds like a lot of tire but it worked until I started dropping everything. I did the arning drop and cut 1 and 1/2 coils off the big block springs I had. I am running a 428cj. I was 3'' over the tire at rest so I went extreme. cut them and looked great. I guess a monkey got in there overnight and bam it dropped to right over the tire. Looked great if it were a trailer queen. I had to start over. I pulled some used coils from 302 71vert with air. put it right back where I was to start. This is a very frustrating process. It will be trial an error. It's almost impossible to for someone here to tell you exactly what you need. every application is different. I will probably end up cutting a 1/2 coil off the springs I have now. If you find something that will raise a spring 1'' let us know. If that is the case, I can get my bb springs back out and give it a go
 
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