Giant 64 kit vs q80

D1cker1 · Post by **D1cker1** » Wed Sep 05, 2012 8:34 am

Ive seen some broncos with giant's 64 kit with 16" shocks. It's been a question of mine if it's worth it..

Q80/f53
Are the suspension travel numbers that much different and it's ability in the deep whoops.

My questions maybe unclear..so don't get upset.. I'm here to learn

I' guess I'm asking is this kit worth it if your shocks are through the bed?

tcm glx · Post by **tcm glx** » Wed Sep 05, 2012 8:54 am

D1cker1 wrote:Ive seen some broncos with giant's 64 kit with 16" shocks. It's been a question of mine if it's worth it..

Q80/f53
Are the suspension travel numbers that much different and it's ability in the deep whoops.

My questions maybe unclear..so don't get upset.. I'm here to learn

I' guess I'm asking is this kit worth it if your shocks are through the bed?

Interested in thoughts on this as well....

ChaseTruck754 · Post by **ChaseTruck754** » Wed Sep 05, 2012 10:18 am

I think part of the advantage with giant's kit is the spring under helps reduce axle wrap kind of like the 2 link does.

As for travel numbers - Geoff claims more inches than I've seen with the F53's, but when I put the 64's on my supercab I didn't get what Geoff claimed. HOWEVER, I used stock type leaf hangers vs. paying what Geoff wanted for his hangers, AND I did NOT notch the frame for bump travel. That being said I'm pretty sure I got 15" out of the things with no negative arch on the springs. If I went to a fabricated shackle hanger I'd get a few more inches of droop out of it. Still not the 21" or so I think I've seen claimed, but not bad at all.

Silverslk · Post by **Silverslk** » Wed Sep 05, 2012 11:31 am

I had a long talk with John in Baja after Bills shock class. He told me there would be no meaningful gain going spring under. He said I would still end up needing a 2 link regardless of what you hear and that most travel gained (really only droop on a Bronco) would come at cost of DS plunge..... I hope I got what he said right.

philofab · Post by **philofab** » Wed Sep 05, 2012 11:40 am

ChaseTruck754 wrote:I think part of the advantage with giant's kit is the spring under helps reduce axle wrap kind of like the 2 link does.

As for travel numbers - Geoff claims more inches than I've seen with the F53's, but when I put the 64's on my supercab I didn't get what Geoff claimed. HOWEVER, I used stock type leaf hangers vs. paying what Geoff wanted for his hangers, AND I did NOT notch the frame for bump travel. That being said I'm pretty sure I got 15" out of the things with no negative arch on the springs. If I went to a fabricated shackle hanger I'd get a few more inches of droop out of it. Still not the 21" or so I think I've seen claimed, but not bad at all.

You also did not buy the springs from him.

ChaseTruck754 · Post by **ChaseTruck754** » Wed Sep 05, 2012 11:52 am

Are you saying they are not his springs? or what?

*edit* thought about this for a minute & thought maybe you were going to the high price of hangers coming from me buying the springs elsewhere (I got them "used" on DR = mocked up but not run)???

D1cker1 · Post by **D1cker1** » Wed Sep 05, 2012 11:52 am

Talking to a member here.. He was able to get 20" travel.. With slight frame notching. Is this a difficult process?
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What's DS plunge?

ChaseTruck754 · Post by **ChaseTruck754** » Wed Sep 05, 2012 11:54 am

Frame notching difficult or installing the springs difficult?

DS = driveshaft plunge.

philofab · Post by **philofab** » Wed Sep 05, 2012 11:56 am

ChaseTruck754 wrote:Are you saying they are not his springs? or what?

*edit* thought about this for a minute & thought maybe you were going to the high price of hangers coming from me buying the springs elsewhere???

There is no way to know if they are the same as what he sells or not.

D1cker1 wrote:Talking to a member here.. He was able to get 20" travel.. With slight frame notching. Is this a difficult process?
------------------------

What's DS plunge?

The frame notching is not bad but I wouldn't recommend it unless you are caged. The notch will create a stress point on the frame.

DS plunge is Drive Shaft plunge. The the shaft plunges too much it can bind during suspension travel.

D1cker1 · Post by **D1cker1** » Wed Sep 05, 2012 12:06 pm

ChaseTruck754 wrote:Frame notching difficult or installing the springs difficult?

DS = driveshaft plunge.

Frame notching..
I see it allows the axle travel up more

Is it just cutting a Notch and connecting the cage tube onto the frame?

Do we know how much droop before DS plunge... More than 20".?

Polarcub · Post by **Polarcub** » Wed Sep 05, 2012 12:30 pm

FWIW.......The points already mentioned above are all valid IMO. Idid a whole bunch of research and question asking on this myself and I came to the conclusion that between price and labor that going spring under would not yield enough of a usable advantage in my bronco. Based on the springs being located below the axle you loose compression which we need and IMO is more important than massive droop. The debate on 2 link will rage but after talking to a few folks even with the spring under they found they needed a 2 link. Alot of that will depend on tire choice and HP to the rear wheels. I personally do not want to hassle with notching the frame either. With all that being said the J40/F53/Q80 springs provide ample travel and are pretty easy to make work very very wellI feel shock mounting locations have more value for non race applications. Just my 2 cents.

D1cker1 · Post by **D1cker1** » Wed Sep 05, 2012 2:03 pm

I understand what your saying polar..

Another question... Going through the floor with shocks will only provide what.. A cooler shock? Slight increase in travel?

AussieRod · Post by **AussieRod** » Wed Sep 05, 2012 2:05 pm

I think the main advantage of spring under in the Giant kit is the leaves will not go into negative arch (instant killer of leaf springs) at full compression. Using a softer leaf pack (even spring under) would still have axle tramp / wind-up to a lesser extent. On his website, the 64 " spring also has triple wrap ends (correct me if I am wrong). I still cannot understand why you guys prefer a 2.5" wide spring V the 3" leaves fitted to all of Ford's 4WD trucks and Broncos. The narrower leaf will break easier under severe use much quicker than the 3". I am sure Ford fitted 3" leaf springs under their 4WD products for a reason, so why would anyone want to use a weaker spring?

ChaseTruck754 · Post by **ChaseTruck754** » Wed Sep 05, 2012 2:24 pm

philofab wrote:
ChaseTruck754 wrote:Are you saying they are not his springs? or what?

*edit* thought about this for a minute & thought maybe you were going to the high price of hangers coming from me buying the springs elsewhere???
There is no way to know if they are the same as what he sells or not.

I got them from an ex Giant employee and called both Geoff & Deaver to ask how to verify & got the answers. I guess they COULD be a custom, spring under pack, but the likelyhood of them actually being something different is very slim IMO.

cs_drums · Post by **cs_drums** » Wed Sep 05, 2012 4:26 pm

I have the 64 kit. I ran a longer shackle to lower the ride height then notched the frame to gain up travel back. The limiting factor is the DS with the short shaft of a e4od your limited to 18-19 before binding. I have strapped at 21 with the additional 3" notch up travel. I am hoping to button up my build in he next few months and let you all know how it works. It's all about time and money I had he money to go with the giant kit when I started my build so I went for it.

philofab · Post by **philofab** » Wed Sep 05, 2012 4:58 pm

D1cker1 wrote:Another question... Going through the floor with shocks will only provide what.. A cooler shock? Slight increase in travel?

A shock that is way easier to tune. The decreasing rate is not a good combo with leaf springs.... but it can be made to work.

yikes · Post by **yikes** » Wed Sep 05, 2012 5:12 pm

One thing that I never read in people's consideration is the fact that spring under applies 100% of the load during compression to the bolts/u-bolts. In other words, it tries to rip the bolts apart every time you hit a bump, vs the rear end pushing up on the springs with spring over. Think about it.

ChaseTruck754 · Post by **ChaseTruck754** » Wed Sep 05, 2012 5:33 pm

never thought about that aspect Brian but it does make sense. I guess if it was really a major issue then all vehicles would be make spring under.

D1cker1 · Post by **D1cker1** » Wed Sep 05, 2012 6:35 pm

yikes wrote:One thing that I never read in people's consideration is the fact that spring under applies 100% of the load during compression to the bolts/u-bolts. In other words, it tries to rip the bolts apart every time you hit a bump, vs the rear end pushing up on the springs with spring over. Think about it.

That's a good point..
I wonder how many tacoed rear ends there are as a result

philofab · Post by **philofab** » Wed Sep 05, 2012 8:15 pm

My crew cab is spring under and I've never had an issue. I tow trailers constantly. 37" tires, 450 ft lbs of torque, 7k weight.

My u bolts are 9/16.

9/16 grade 5 bolts have a fail point of 29,000 lbs tension, and there are four u bolts holding my rear end together. That is 116,000 lbs of tension before failure. My suspension will compress at a much lower number than that. Once it bottoms out the load would be transferred to the frame. Many OE trucks on the road are spring under, well over a million I'd say.