Completely disagree with this statement. Short side forward to keep pinion angle in check thru the travel of the spring, which is not a big deal especially with a sprung under truck where there is not much travel.
Flipping the rear springs?
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Completely disagree with this statement. Short side forward to keep pinion angle in check thru the travel of the spring, which is not a big deal especially with a sprung under truck where there is not much travel.
so tell me Mark, what is this information bassed on?
The information is based on leaf spring measurements.
Do you have different measurements? Or do you not believe him?
The information is based on leaf spring measurements.
Do you have different measurements? Or do you not believe him?
I can assure you its NOT based on measurements. opinion, or hearsay, but not measurements
bust out a tape measure
Mark W
Yep, I really don't really care that much I guess.
While FC may be a bit abrasive about it, I can't say that he is wrong. About the measurements anyway.
A flipped FJ40 spring will give you 4 inches of wheelbase length at each end. An FJ55 spring under a '40 will give you 4.5 inches of gain at each end.
My comment about another 1.5 inch by reversing the '55 springs... Wrong. I've been doing a bit of playing with different spring combos and I got the offset of the 55 springs mixed up. The frame end of the '55 spring is longer than the shackle end. Opposite from the '40.
I made a mistake as I sat in front of the keyboard relaxing at the end of the day. It happens.
As to the comment that I'm just repeating other peoples statements or passing along opinion as fact (how does opinion come into play in measurements anyway?).
If I simply repeat what someone has told me, I clearly state it as such. If I offer an opinion, I also make it a point to identify it as just that. If I put something out as a fact it is because I have touched it, measured it, used it, done it.
Mark...
A flipped FJ40 spring will give you 4 inches of wheelbase length at each end. An FJ55 spring under a '40 will give you 4.5 inches of gain at each end.
My comment about another 1.5 inch by reversing the '55 springs... Wrong. I've been doing a bit of playing with different spring combos and I got the offset of the 55 springs mixed up. The frame end of the '55 spring is longer than the shackle end. Opposite from the '40.
I made a mistake as I sat in front of the keyboard relaxing at the end of the day. It happens.
As to the comment that I'm just repeating other peoples statements or passing along opinion as fact (how does opinion come into play in measurements anyway?).
If I simply repeat what someone has told me, I clearly state it as such. If I offer an opinion, I also make it a point to identify it as just that. If I put something out as a fact it is because I have touched it, measured it, used it, done it.
Mark...
I am a complete noob but isn't the only purpose of flipping springs is to bring down the departure angle.
And I thought you also were suposed to move the shackle also so it would be less likley to get caught on something
And I thought you also were suposed to move the shackle also so it would be less likley to get caught on something
It changes the departure angle but it does increase the wheelbase as well, like they were saying by 4".
Mark W
Yep, I really don't really care that much I guess.
Improved departure and approach angles are one of the benefits of increasing the wheelbase of a '40. Better handling is another major improvement. Gentler driveline angles is another. Room for longer drivetrain combos is yet another gain.
If you are refering to a shackle reversal on the front is when you say "moving the shackles" then that is a debatable conversion. Many people (myself included) feel that it has more adverse effects than positive ones.
A shackle reversal is never done on the rear end.
Shackles "getting caught" on things is not a common occurance and is most often either due to driver error or is something that would simply become "spring mount" getting caught on things if the rig had a shackle reversal.
Mark...
So, for example.
If I were to put my front axle under my springs, a spring reversal would make it a bit gentler on the front driveline because the angle of the driveshaft would not be as great.
Also, it I left the fixed end of the spring where it is at the back, I would not get as much twisting action of the pinion.
Is this accurate?
Would I still need something to keep the pinion located properly?
Mark W
Yep, I really don't really care that much I guess.
Correct on both counts.. basically.
The pinion will still swing with the movement of the springs, but the swinging will keep the pinion pointed towards the T/C as the suspension cycles. If you do a shackle reversal the swinging/flexing of the suspension will cause the pinion to point further way from the T/C as it cycles. It increases the need for ujoint deflectio nand for slip joint length.
Not sure what you mean by "keeping the pinion located properly".
If you are referring to using an anti-wrap bar, then reversing the springs doesn't affect this much one way or the other. In theory the longer leg will allow more wrap. In the real world I have never encountered an increase in spring wrap in a rig with reversed springs.
An anti-wrap bar is never a bad idea in an SOA rig though.
Mark...
This is great info, thanks. I have 3 fj40s now and even more parts, all are buggy materal so I can afford to do some experimenting without worrying about breaking something.
My goal is to have something good for heavy and deep mud.
My goal is to have something good for heavy and deep mud.
There is too much friction here.
Back on subject, on FJ55 rear springs, do you need to remove any leafs for ride comfort? I am assuming they are thicker springs than an FJ40 spring. I had an FJ55 once or twice in my life, but never looked that far.
And there was no length issues as far as mounting to the stock rear shackle? Or do you move the shackle mount back further?
Lastly, if there is a 4" spring for the FJ55, has anyone had any experience with these mounting them on an FJ40? What was the ride like?
I appreciate all the insight and knowledge you guys have on this board mistakes (which are few, and usually owned up to) and all. I love anything Cruiser. Thanks.
Regards.
Back on subject, on FJ55 rear springs, do you need to remove any leafs for ride comfort? I am assuming they are thicker springs than an FJ40 spring. I had an FJ55 once or twice in my life, but never looked that far.
And there was no length issues as far as mounting to the stock rear shackle? Or do you move the shackle mount back further?
Lastly, if there is a 4" spring for the FJ55, has anyone had any experience with these mounting them on an FJ40? What was the ride like?
I appreciate all the insight and knowledge you guys have on this board mistakes (which are few, and usually owned up to) and all. I love anything Cruiser. Thanks.
Regards.
Mark W
Yep, I really don't really care that much I guess.
In my experience there is no need to remove any leaves from the '55 springs when swapped under a '40. Of course we tend to travel heavily loaded up here, but from our uses the '55 spring is could still stand to be stiffer if anything. The individual leaves are the same width and thickness as the '40 springs. There are more of them however.
The ride is very smooth. I don't move the shackle mount because I like to use a longer shackle at a gentle angle for increased suspension travel and a softer ride.
Mark...
abrasive? me? NEVER!
you can,.... but you would be wrong again
to revisit my orig post,... the long end of a 40 main leaf IS the same length as either side of a 55 rear main leaf. How can the wheel base that you would gain possibly differ? the following pic is of a 40 long side....
oh cmon Mark,... I give respect where respect is due! and I have nothing but respect for ya, and my reply was by no means questioning your integrity or knowlege. hell,..... common knowlege dictates "watley knows Cruisers".
that being said, my post was intended to help some guy out that was lost in "the sea of missinformation" that is the internet. If your information preceded mine, I would not have felt compelled to publicly correct you. but thats just ME.
My "tape measure pics" where not posted to prove you wrong, just prove ME RIGHT!
FC
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If you use 55 springs, is there a need to relocate the spring mount or does the shackle make up for the difference.
I you decide to run 55 springs in the rear of a 40, you can do it a couple ways,...
use a smaller shackle and reverse/relocate the shackle hanger.
OR
leave the shackle hanger and spring hanger in the EXACT same place and run a longer shackle. this option will give you a softer ride due to the increased shackle angle.
only other side note that hasent been addressed, is bushings. 55 springs eyes have a larger ID than 40's and run a larger Pin. the 55 bushings also have a slightly larger shoulder. you will need to purchase aftermarket bushings that can "adapt" the 55 springs to the smallerpin dia. of a 40. (I get mine from Marv)
orangefj45
Supporting Vendor
haha, fc actually said group hug. all y'all mudders must be rubbing off on him (not in that way don
).
anyways, i just put a pair of 55 springs in the back of my 40 with the SOR bushings (as fc mentioned) and i'm running slightly longer shackles from dan aka gravel maker. makes for a nice ride, great articulation and longer wheelbase without having to run a spring in a way that it was'nt intended or worrying about running spring shims to correct the pinion angle.
then again, my rig has a 60 out back and i'm putting new perches on it. i'll be adding to my build-up thread shortly.
group hug. bawahahaha, funnay! karl/slingblade voice "funnay queer, not funnay haha!"
).anyways, i just put a pair of 55 springs in the back of my 40 with the SOR bushings (as fc mentioned) and i'm running slightly longer shackles from dan aka gravel maker. makes for a nice ride, great articulation and longer wheelbase without having to run a spring in a way that it was'nt intended or worrying about running spring shims to correct the pinion angle.
then again, my rig has a 60 out back and i'm putting new perches on it. i'll be adding to my build-up thread shortly.
group hug. bawahahaha, funnay! karl/slingblade voice "funnay queer, not funnay haha!"
