1975 Sweet Pea go-fast'ish build

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FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
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1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

I read a little jab about the EB guys holding back so I thought, why not?!;) I am not a fab guy so it's being bought not built. LOL

We've had this since 2006 and been plunking around the garage since as a mall crawler & grocery getter - my wife actually smiled when she drive it!;). But, I have moved to kansas and am only 2.5 hours from the dunes and decent trails (Disney, OK; KS Rocks; Tuttle Creek) so it was time to get with it and find a shop to help make it fun. Going from a 5.5" lift with radius drop brackets.

Doing a dual purpose type build (I Hope). Battlement Fab radius arm setup with leaves out back. King 2.5 Smoothies with adj ressies at all four and WH 4x4x2 / hydro assist steering.

Here's some pics of where we start and about midway thru install...finally getting close!

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And now:

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Rmc
El Jefe
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Re: 1975 Sweet Pea go-fast'ish build

Post by Rmc »

Those arms totally remind me of a set I built for my old Cherokee. They will work well. Love the color on that thing too.
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

Thanks RMC! I'm stoked. Seen many a flex shot with similar setups and looks to be a nice one-won't know until we get her in the dirt.
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Wrightracing.net
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Bronco Info: 1972 Bronco with an 86 chassis, full cage and Long travel coil-over suspension.
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Re: 1975 Sweet Pea go-fast'ish build

Post by Wrightracing.net »

That's some nice work. OK, my geeky geometry side of my brain has a hard time wrapping around how the pinion angle does not go out of the safe zone and bind. I am assuming the wheel travel is limited with this design? I am not saying anything bad about it just an academic question.
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

Wrightracing.net wrote:That's some nice work. OK, my geeky geometry side of my brain has a hard time wrapping around how the pinion angle does not go out of the safe zone and bind. I am assuming the wheel travel is limited with this design? I am not saying anything bad about it just an academic question.
Probably a great question! As it sits on the stands in the pics it is about 4-5 inches below ride height for mock up. It will be strapped but not quite there. The chubs are in stock locations and have not been cut and rotated. I suppose the first real run we'll know how good or bad it will be. So far I know that an Early Bronco was run in the KOH stock class in 2013 with this very setup. I saw the thread on pirate and sent a message to him asking if he would mind sharing some additional build pics. He just replied in the affirmative so we'll have a closer look when he can send them.

Didn't take it as bad...always welcome feedback and criticisms!!!

Cheers!
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

FlogginHarvey wrote:
Wrightracing.net wrote:That's some nice work. OK, my geeky geometry side of my brain has a hard time wrapping around how the pinion angle does not go out of the safe zone and bind. I am assuming the wheel travel is limited with this design? I am not saying anything bad about it just an academic question.
Probably a great question! As it sits on the stands in the pics it is about 4-5 inches below ride height for mock up. It will be strapped but not quite there. The chubs are in stock locations and have not been cut and rotated. I suppose the first real run we'll know how good or bad it will be. So far I know that an Early Bronco was run in the KOH stock class in 2013 with this very setup. I saw the thread on pirate and sent a message to him asking if he would mind sharing some additional build pics. He just replied in the affirmative so we'll have a closer look when he can send them.

Didn't take it as bad...always welcome feedback and criticisms!!!

Cheers!
Didn't see an edit button...;) but just took a closer look at the pics on my phone and realized a dumb one: the drive shaft is not hooked up rather just hangin out for mock up. The pinion angle isn't quite as pitiful as it looks in the pics. But we'll definitely keep our eye on it!
Rmc
El Jefe
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Re: 1975 Sweet Pea go-fast'ish build

Post by Rmc »

The caster and pinion angle are married in that set up. Meaning castor is in the axel and as long as the drive line pivot and the arm pivots were set up in line with eachother travel is only limited by the springs falling out and usable angle of the drive line u joint or the panhard bar hitting a crossmember. You can articulate and droop feet with a properly working long arm set up. Strong steering is a must and set up the pinion angle then cycle. Reason for strong steering is the castor is long gone when drooped.
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

Thanks for the info and tech help RMC! So, if I understand correctly (dumbing it down for me) the pivot point (Hiem location on frame) should be in line (or next to) the cv joint at the transfer case?

I'll check letter in the week when I can pop by the shop prior to bur ING everything in
Rmc
El Jefe
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Re: 1975 Sweet Pea go-fast'ish build

Post by Rmc »

For an unbound pivot point the centerline of all pivots needs to be inline with eachother. Meaning the frame rail pivots and the u joint at the front of the transfer case in a straight line across with eachother.
Rmc
El Jefe
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Re: 1975 Sweet Pea go-fast'ish build

Post by Rmc »

A little advise if I may also. Make sure the pivot box wraps around the outside as well as the underside of the frame to resist shear load of the front end pushing back agianst the pivot boxes. If there just face welded it may break the box off when you hit a near verticle rock while trying to go over it because all the speed and inertia foreward has to be resisted by those boxes. When they don't or can't your broke down in the middle of no where. Ill quote in saying " overbuilt is under rated". think strong... Like impossible to break strong and that's where you start from. Don't go rediculious like 1" plate on everything but 3/16 or 1/4 for radius arm boxes all day. I prefere 1/4 for full sized trucks. Just my 2 cents for what it's worth.
toddz69
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Re: 1975 Sweet Pea go-fast'ish build

Post by toddz69 »

Wrightracing.net wrote:That's some nice work. OK, my geeky geometry side of my brain has a hard time wrapping around how the pinion angle does not go out of the safe zone and bind. I am assuming the wheel travel is limited with this design? I am not saying anything bad about it just an academic question.
Yes, the driveshaft usually is the limiting factor on the travel of the front end on these trucks. The driveshaft is usually shorter than the radius arms and keeping the front end rotated for proper caster aggravates the situation.

Keep an eye on the front driveshaft. If you're running 4-5" of lift (looks like you might), I'll almost guarantee you'll run into some binding issues at the pumpkin with not a lot of droop.

The proper way to fix is is to cut and rotate the C's on the axle housing for additional caster and if you're running a longer drivetrain than stock, the driveshaft becomes longer and the upper pivot point may be on the same rotational axis (or close) as RMC notes in his post.

Todd Z.
Rmc
El Jefe
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Re: 1975 Sweet Pea go-fast'ish build

Post by Rmc »

Not sure if anyone makes them but I recall I put degree shims into the trans/transfer case mounts to elievate some angle on the drive line because I raised the ride height. Granted that's jeep stuff but still solid axel. Anyone know if a similar set up is used on the eb's?
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Wrightracing.net
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Re: 1975 Sweet Pea go-fast'ish build

Post by Wrightracing.net »

Isn't that's what the adjustability on the upper hiem joint on the upper link at the housing is for? Small adjustments to pinion angle.
toddz69
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Re: 1975 Sweet Pea go-fast'ish build

Post by toddz69 »

Rmc wrote:Not sure if anyone makes them but I recall I put degree shims into the trans/transfer case mounts to elievate some angle on the drive line because I raised the ride height. Granted that's jeep stuff but still solid axel. Anyone know if a similar set up is used on the eb's?
Yeah, those are used/common (drop brackets in particular) with the Jeep crowd but not used in the EB world. The EB mounts don't lend themselves to shimming and installing shims to help the front driveline makes things worse for the rear driveline, which is usually of greater concern.

Todd Z.
toddz69
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Re: 1975 Sweet Pea go-fast'ish build

Post by toddz69 »

Wrightracing.net wrote:Isn't that's what the adjustability on the upper hiem joint on the upper link at the housing is for? Small adjustments to pinion angle.
Yes. And caster.

Todd Z.
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

Whew! Glad I started a thread here!!! Thanks for the heads up and insight guys! Both drive shafts were custom longer lengths a few years back when I picked her up but prior to seeing TomWoods anywhere... And yes, very good eye Todd. Was 5" and now 4" lift springs ala Wildhorses with the rest of the new gear.

We will most certainly keep an eye out for the above. When I have more pics I will keep them coming!

THANKS!!!
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PBR
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Re: 1975 Sweet Pea go-fast'ish build

Post by PBR »

Nice looking rig!

Only thing I noticed is that your exhaust is going through your leaf springs, when the suspension compresses won't you smash your exhaust?
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

Hah! Why yes, you are correct!;). We are cutting it back and dumping straight outta the bottom for now to get her back on the road. Eventually when the summer is over I'll get things more "permanent" and hopefully go out the fender just in front of the rear wheel opening... Ah bronco projects! LOL
FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

After the holiday weekend we finally have some time for updates. Nate has had a rocky go after a Pancreatitis and surgery - so glad his recovery is going well! The rear is getting sorted and still chewing on the shock mounts and front end setup.

RuffStuff anti wrap, new springs, shock mounts and King shocks!

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FlogginHarvey
Posts: 37
Joined: Thu Jul 04, 2013 12:42 pm
Bronco Info: 1975 EB 302, C4, D20, d44, F9", Battlment Fab radius arms, king 2.5 smooth body reservoirs
Location: Kansas
Contact:

Re: 1975 Sweet Pea go-fast'ish build

Post by FlogginHarvey »

This is killing me! A few more pics...

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