Coil bound king springs (rear KTPR-102)

[WDTP Junior Member Find all posts View Profile Close WDTP]

Hi
I have just fitted my new King springs. I choose King KTRR-102 [Edit it should be KTPR-102] plus air bags for when towing.

The KTPR-102 are a comfort spring, they are progressive meaning the the top four or five coils are close together and the rest get further apart. As I understand it the idea is that as you add a load (or hit a bump) the upper coils become coil bound and effectively the spring rate increases.

My issue is that the top four coils are coil bound at no load. I have plenty of height the new springs gave me a 70mm lift over the sagging factory springs. My height was 750, it is now 820 with 900mm at full droop. Even at full droop the top two coils are still coil bound and the next few coils are only about 2mm apart. I plan to give King a ring (but I need to fix my front suspension first so it might be on Monday) but before I rang I though I would see if anyone else had had this problem.

I am wondering if the springs weren't made quite right, in the suspension data base they are described as having a 390mm length, I measured mine before I fitted them and they were more like 435mm.

Not looking forward to changing them it was a difficult job without undoing the brake lines and I bought the springs from interstate, beginning to regret doing this task myself :-)

Greg

[Guest Close Guest]

The KTRR-102 are regular looking coils. They look like this http://www.pradopoint.com/showthread...R-102-REAR-x-2

[WDTP Junior Member Find all posts View Profile Close WDTP]

The KTRR-102 are regular looking coils. They look like this http://www.pradopoint.com/showthread...R-102-REAR-x-2

My mistake, I have KTPR-102 , I will see if I can edit my post. (I originally was going to get the KTRR and that is what I had I my notes)

[wholesalesuspension Advanced Member Find all posts View Profile Close wholesalesuspension]

The KTPR-102 are a stacker design coil & will sit bound at normal ride height.
This is similar in principle to another brand of coils with a good marketing name of "flexy coils" which also run a stacker design.
They are a revised design that is widely used in Commodore's etc with good success.
The bound coils will open up on droop to essentially make the coil a little longer on droop without it becoming untrapped.

KTRR-102 is 390mm Free Height.
KTPR-102 is 410mm Free Height.

Regards, Jason.

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

Hey Jason,

It's ok to say DOBINSONS FLEXI COILS

They supported the gtg this year to the value of $1000.00 funky aqua flexi coils........whoopa whoopa

[wholesalesuspension Advanced Member Find all posts View Profile Close wholesalesuspension]

Hahaha ####. I didn't mean the Dobbo's, i was talking about those Black cheap crud coils that are brand named Flexi coil.
They are a Chinese wonder of the 21st century using a design pioneered 40 years ago. (inset sarcasm here)

Regards, Jason.

[WDTP Junior Member Find all posts View Profile Close WDTP]

The KTPR-102 are a stacker design coil & will sit bound at normal ride height.
This is similar in principle to another brand of coils with a good marketing name of "flexy coils" which also run a stacker design.
They are a revised design that is widely used in Commodore's etc with good success.
The bound coils will open up on droop to essentially make the coil a little longer on droop without it becoming untrapped.

KTRR-102 is 390mm Free Height.
KTPR-102 is 410mm Free Height.

Regards, Jason.

Jason thanks for that explanation, I was a bit worried that something wasn't right, you have allayed my fears.

With my bilstien BE5-A715 Prado 150 shocks these springs are still at bit coil bound at full droop. I expect these springs could be used quite effectively with extended travel rear shocks (probably 30-40mm longer than mine) without the springs becoming untrapped.

The free height was a LOT longer than the factory springs.

Regards Greg

[Jkspinner Junior Member Find all posts View Profile Close Jkspinner]

Jason, you may find that the "Flexy Coils" bring marketed in Australia are made by Kings. In live axle 4wd's they are generally used to get some more fex, ie, install 2" Flexy coils, which have a free height much longer than normal linear coils, and use a 4" shock. The main part of the coil are generally linear, however the top 4-6 wires are tapered, and often spaced further apart.
The Dobbo Flexy coils are usually a 2 stage design, where the bottom of the coils are usually linear, then they have transition coil or two, then the top 3 or 4 coils are stacked. With this design, you generally need to extend the bumpstops to prevent coil bind.
Maybe we are talking about different "Flexy Coils"

Hahaha ####. I didn't mean the Dobbo's, i was talking about those Black cheap crud coils that are brand named Flexi coil.
They are a Chinese wonder of the 21st century using a design pioneered 40 years ago. (inset sarcasm here)

Regards, Jason.

[wholesalesuspension Advanced Member Find all posts View Profile Close wholesalesuspension]

Jason, you may find that the "Flexy Coils" bring marketed in Australia are made by Kings. In live axle 4wd's they are generally used to get some more fex, ie, install 2" Flexy coils, which have a free height much longer than normal linear coils, and use a 4" shock. The main part of the coil are generally linear, however the top 4-6 wires are tapered, and often spaced further apart.
The Dobbo Flexy coils are usually a 2 stage design, where the bottom of the coils are usually linear, then they have transition coil or two, then the top 3 or 4 coils are stacked. With this design, you generally need to extend the bumpstops to prevent coil bind.
Maybe we are talking about different "Flexy Coils"

Hi JK. Kings don't market any of their coils as a flexy coil for any of their range as far as i'm aware.
The "Flexy Coil" name is a good marketing name, as a lot of people seem to think that if they fit a flexy coil that the vehicle will flex up better, which is just not the case.
The amount of calls i take for a basic 2" lift kit with people asking for flexy coils is growing by the week.
There is zero benefit in this application & this is not what Kings made theirs to do, although it has that benefit of the little extra open length.
The shock, swaybars & arms etc is usually the limiting factor in travel in most vehicles running basic lifts.
It's all well and good to put a coil in that can give a 2" lift, and also flex open as far as a 4" coil, but then it becomes difficult finding a suitably valved shock that'll happily do the shorter closed length paired to the extended open length. That's where it becomes tricky & most end up with a compromise, or extended bumpstops that limit the compression anyway.


Regards, Jason.

[Jkspinner Junior Member Find all posts View Profile Close Jkspinner]

Hi Jason
They are not marketed by Kings, they are marketed by Suspension Stuff and a few others, but made by Kings, and designed by Kings. I to can see very little benefit in a Prado, maybe only enabling the use of a 620mm shock on a 2" lift. But on a Nissan Patrol or Jeep Wrangler, they are fantastic, especially for the JK where there is an infinite amount of after market gear to remove any limiting factors such as brake lines, sway bars and remote resiviour shocks with very short compressed length. Brake line drop brackets and sway bar extenders or disconnects, bump stop extenders are standard items on a lift kit for a JK wrangler.

Hi JK. Kings don't market any of their coils as a flexy coil for any of their range as far as i'm aware.
The "Flexy Coil" name is a good marketing name, as a lot of people seem to think that if they fit a flexy coil that the vehicle will flex up better, which is just not the case.
The amount of calls i take for a basic 2" lift kit with people asking for flexy coils is growing by the week.
There is zero benefit in this application & this is not what Kings made theirs to do, although it has that benefit of the little extra open length.
The shock, swaybars & arms etc is usually the limiting factor in travel in most vehicles running basic lifts.
It's all well and good to put a coil in that can give a 2" lift, and also flex open as far as a 4" coil, but then it becomes difficult finding a suitably valved shock that'll happily do the shorter closed length paired to the extended open length. That's where it becomes tricky & most end up with a compromise, or extended bumpstops that limit the compression anyway.


Regards, Jason.

[wholesalesuspension Advanced Member Find all posts View Profile Close wholesalesuspension]

Speaking of JK Wranglers, a mate had one at his workshop last week fitting a 5" kit to with remote reservoir Fox shocks and Fox hydraulic bump stops. It was Porn!!!
I left a little drool behind :-)

Regards, Jason.