Giant 64 kit vs q80

[cs_drums]

I would say its not much of an issue. All of the load on the front is through 1/2" bolts on the coilovers. There are plenty of race trucks to attest to both spring over and under. What is the recommended life span of u-bolts?

[AussieRod]

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.

Agreed, however having worked at a spring maker in the past, I have seen axle tubes literally crushed by over use of the rattle gun tightening up U bolts. Most are at least Grade 8 or higher in spring under configuration. Philo does make a good point, though

[Deleted Account]

The kit does work well. however it is expensive. it will still need 2 link and i realy dont like my springs and spring plates draging in the dirt and rocks. The one i did sat almost stock hieght. looks cool. but it sits into the bump zone in the bypass. I dont see the "value" in having 2500 into your leaf setup. the kit is 1600 i think. and then you have all the fab to insall it. and the 2 link. And to make it worth while you need more drivshaft then a bronco has anyways. A simple 4 link setup would be better and not much more. The good thing about leafs is that they are cheap. i would just get a set of q80s and a good set of shocks.. going through the floor is a great option if you can. but unless your fully caged its hard to do in a bronco. getting them outboard is a big help in stability and a longer shock will stay cooler and be eisier to tune.

[Kel Fab Creations]

I have 64's for my build collecting dust right now but will eventually go on. I am gonna run 2.5 x 12" king bypass's under the floor and have no plans to notch the frame. We have had 64's on my bros truck for a few years now with maybe 10 different weekend runs on it and from what I've seen they drop out way better than any ranger spring over long travel leaf. With that said, I have seen many broncos on here with spring over that handle amazing. I originally planned on going spring over but stumbled across a used 64 kit with a pretty fresh prep on the springs for a good deal so I jumped on it. If I hadn't came across the used 64's I would have bought spring over. Either way I dont think you can go wrong as long as you take the time to tune the shocks accordingly.

[cs_drums]

I have 64's for my build collecting dust right now but will eventually go on. I am gonna run 2.5 x 12" king bypass's under the floor and have no plans to notch the frame. We have had 64's on my bros truck for a few years now with maybe 10 different weekend runs on it and from what I've seen they drop out way better than any ranger spring over long travel leaf. With that said, I have seen many broncos on here with spring over that handle amazing. I originally planned on going spring over but stumbled across a used 64 kit with a pretty fresh prep on the springs for a good deal so I jumped on it. If I hadn't came across the used 64's I would have bought spring over. Either way I dont think you can go wrong as long as you take the time to tune the shocks accordingly.

I agree. Like I said earlier they are both proven setups its just about the time and money you want to invest.

[Polarcub]

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?

No...going through the floor allows you to have better shock angles and placement. Keeping the shocks under the bed your pretty much limited to a 12" strok with some crazy angles that can be challening to valve but they can and do work well. If your willing to go through the floor your looking at 14"-16" stroke shocks but the mounting becomes laborous and can get a bit overwhelming. I am through the floor and dont regret it but I have to completely redo the way mine is set up soon.

[fordf100amc]

Im running the giant 64 leafs but i made all my own spring mounts and shackles. I have 19 inches of travel with my set up using a 18 2.5 bypass shocks outboard. My bronco is fully caged and is not not notched. Im building it to race in class 3 so cant notch the frame. Also i went with a c6 and gained around 8 inches in driveline length over the E4OD. My driveline plunge is about an inch now. I dont have any miles on it but i will in a month or so. Just finished the front suspension this week, built new radius arms that are hiemed and welded to the beam, and trussed the beams. 14" coilovers and 2.5 bumps. Im cycling 17 inches up front. Just need to buy some rear bumps and my suspension is ready to go. As soon as I get some drive time on it i will let you guys know how it feels.

[only1mikey]

I'll chime in here.

While I don't have any first hand experience with a Giant 64 kit of a bronco, I have seen Giant 64 kits in action on multiple vehicles, and other similar spring under setups. I think the positives of spring under outweigh the negative for go-fast offroading.

I see your point Mark on the ride height of the Giant 64 kits of a heavy bronco, but that doesn't surprise me as these spring work pretty darn well out of the box on rangers and much smaller/lighter trucks.

I know I had to add two leafs to my deavers to get the ride height and weight carry capacity I was looking for.

All and all after a few trips back and forth to deaver, and lots of money out of my pocket, I have come to the conclusion that this is the best these set of leaf springs are going to be. I still don't have the up travel I would like and have a lot of negative arch, which has caused a broken main leaf already.

I'd like to one day get a custom sprung under set of leafs made with a LOT more arch and a slightly lower spring rate then what I have now and relocate all the hangers to bump out with zero or an inch or so of dearch. I shoot for close to 10" of up travel! That would be rad setup.

Oh yeah and do a 2 link of sorts.

Mike

[kylesgorter]

I also have some experience with these springs on rangers. They work incredibly well and the biggest thing i noticed is how much easier to tune the shocks. The springs seem to drop out quick and have a much more desirable preload. They ride awesome. I was able to get 19in without notching using 16in shocks mounted 4.5in off the front of the axle. I did notice some axlewrap and prob would be much worse with a higher powered motor. The ride height was tall, I added 6.5in of ride height into the front beams to get a level stance. A bronco prob would sit much lower our ranger was 4010lbs with fuel.

Spring over seems to be a better choice for broncos as the driveline makes it hard to go over 17-18in. Broncos handle completely different than trucks so what works on a truck might not be the.best for a bronco. I agree that for the cost it is a better idea to just make a simple 4 link.

The other thing I want to say is that the springs are designed to.work with the giant bracketry. A lot of the droop comes from the shackle length and placement. If you don't use the proper brackets you will not have a properly functioning 64 pack

[gunit]

One thing that has not been mentioned in this discussion is that if the spring hangers are re-located on the spring over design that there is a big improvement in performance and longevity of the spring.

The other item is the shackles; people use stock shackles with long travel springs which will always end up in bending or breaking the spring, they use shackles to alter ride height or just pick up any old set without regard to what style and length they should be.

Ideally, the correct length shackle should be made to correspond to the length of the spring and then the spring mounts should be re-located so that the spring lays flat at the point where the axle comes to full bump.

Going through these extra steps will add to both the performance and longevity of the spring.

One other thought is that the spring under design reduces ground clearance by at least 4" on each side. You may be able to miss rocks that would hit the center by moving over a bit but if you have something hanging down on each side there is nowhere to go.

[ChaseTruck754]

The other thing I want to say is that the springs are designed to.work with the giant bracketry. A lot of the droop comes from the shackle length and placement. If you don't use the proper brackets you will not have a properly functioning 64 pack

Unless you take the time to cycle & re-cycle to get the brackets you use to where they work... A pivot point is just that - a pivot point. So if the front mount puts the front of the spring where Geoff had it and the rear is set to where the leafs don't go into negative, arch, etc. how can they "not function properly"???

As for shackles - in talking with Geoff on these he recommended a couple different lengths depending on that was wanted out of the truck. As far as I know his hanger design doesn't change for what length shackles you run, even if you get them from him.

[Agui-E7TE]

I've been thinking about the 2.5-Inch spring vs. a 3-Inch spring (Q80/F53 vs. J40). We bottomed out the Bronco at a high rate of speed and it was enough to break the factory bumpstops off it. It has J40s on it and I'm sure having those 3-Inch wide springs really helped keep the rear end together.

I've got a set of F53s that I was planning on having rebuilt but now I'm considering going with a set of J40s. The stability with those springs is way better than I get with my F53s but what worries me now is eventually when I hit really hard in my Bronco, will the springs probably break when it bottoms out with all my gear loaded in the back.

I'm thinking Rod is right about Ford building them with 3-Inch wide springs for a reason.

[D1cker1]

Augi,

Can another .5" on a spring really provide that much more stability you think?
Could it be the rear shock setup/valving?

[philofab]

Some of you guys put way too much thought and worry into this stuff. All of it works and allows you to have fun.

I did the Baja trip with 12" Rancho RS5000s and stock leaves with a pro comp add a leaf kit. Leaves work pretty well and are proven, weather or not you choose a 64 kit or Deavers.

I'd still have F64s and SAW bypasses but I'm linking my Bronco so I can pull bitches at the local No Fear store.

[tcm glx]

Some of you guys put way too much thought and worry into this stuff. All of it works and allows you to have fun.

I did the Baja trip with 12" Rancho RS5000s and stock leaves with a pro comp add a leaf kit. Leaves work pretty well and are proven, weather or not you choose a 64 kit or Deavers.

I'd still have F64s and SAW bypasses but I'm linking my Bronco so I can pull bitches at the local No Fear store.

Rad!!

[Deleted Account]

I've been thinking about the 2.5-Inch spring vs. a 3-Inch spring (Q80/F53 vs. J40). We bottomed out the Bronco at a high rate of speed and it was enough to break the factory bumpstops off it. It has J40s on it and I'm sure having those 3-Inch wide springs really helped keep the rear end together.

I've got a set of F53s that I was planning on having rebuilt but now I'm considering going with a set of J40s. The stability with those springs is way better than I get with my F53s but what worries me now is eventually when I hit really hard in my Bronco, will the springs probably break when it bottoms out with all my gear loaded in the back.

I'm thinking Rod is right about Ford building them with 3-Inch wide springs for a reason.

Fyi.. the j40 pack moves the rearend back. so you will need a d-shaft and the one thats here rubs the tires on the rear of the wheel openings. I think breaking the bumpstops off is a shock issue mostly.. More spring wont hurt though. I think 3 inch springs are better for most guys here, but not any of the ones that are off the shelf.

[hobbyturnedobsession]

I have j40s but i have a stock shaft

[Deleted Account]

depends on the truck.. more the point was the wheelbase

[hobbyturnedobsession]

Oh ok. I do have the rearend kicked back tho.

[tcm glx]

Augi,

Can another .5" on a spring really provide that much more stability you think?
Could it be the rear shock setup/valving?

Just my two cents..... I'd say so many different things play a roe here....track width, shock valving, coil spring rate in the front, coil over vs coil and shock, etc etc etc........

I've seen both Randy and Jeremy's truck incredibly well, and can equally say the same about a 2.5" spring. Valving is what is important here IMO.

Auggie, bottoming out hard can be a lack of proper bump setup as well as shock setup.