Builds 4508 - Ultra4 Racetruck Build

[snivilous]

Well, on the topic of shocks: 2.5 vs 3.0

3.0 is for sure race size, they are better. But if you weigh twice as much 2.5’s did their job, then half as much weight should really allow them to stay cooler.

In full blown race rigs i have seen 2.0 shocks but monster bypasses. The shock becomes a coil carrier and has no valving to it. All dampening is within the bypass.

Yes I agree on all those points, however my worry is running a 1.5x motion ratio on the trailing arms will overpower a 2.5. A 3.0 has 44% more piston area, so I think it makes sense if that shock is having to react 50% more loads. The front on the other hand, I think there's a good chance a 3.0 is too much shock if I mount straight to the axle.

EDIT: Thinking about it more I think a single 2.5 up front regardless how I set it up is the way to go, assuming I'm within 1000lbs or so of my 3k mark. Here's how I figure it:

On the 80, twin 2.5s with 12s on rebound made me have the bypasses almost maxed out to soften the rebound (let it droop faster). Now a 3.0 is 44% more surface area than a 2.5, and considering this buggy will be for simplicity half the weight, that means the 3.0 needs the same valving as a single 2.5 on the 80. Well 44% less valving with a 12 stack on rebound, is a bit more than a 6 stack. That means that a single 3.0 on the buggy, valved with a .006 stack on rebound will have the same rebound as the 80 which needed LESS rebound to begin with.

Likewise I ran 15s on compression, which is a bit more than 8s for the 3.0s. So on rebound right off the bat I would need to get hard to get shims for good rebound, plus I would probably have too much rebound control, plus I would have almost no way to go softer on rebound if I needed too. Likewise same issues for compression, except that 8s are actually a standard size. All that plus the shock would have trouble getting up to temperature.

Obviously there's more to it, but off the bat it seems like a 3.0 up front will be extremely hard to if even possible to correctly tune. I think for the rear though, it might not hurt to run a 3.0 still. But the rear will probably be a 14" shock, so I can run my 2.5s and see if they are getting too hot or don't have enough damping and can always bump up from there.

 

[Jgunner]

Is that how shock valving works? I would think a bigger shock would be valved the same as everything is larger proportionatly. Sure, valve shims are the same thicknesses, but i would think it all works the same. Mind you, I’ve never gone deep into valving, just played a little with it, i know you have spent way more time on it. I would think a shock tuner business could tune any shock on any type of suspension (as long as the shims are available).

 

[nukegoat]

Is that how shock valving works? I would think a bigger shock would be valved the same as everything is larger proportionatly. Sure, valve shims are the same thicknesses, but i would think it all works the same. Mind you, I’ve never gone deep into valving, just played a little with it, i know you have spent way more time on it. I would think a shock tuner business could tune any shock on any type of suspension (as long as the shims are available).

No, different diameter shims (for different size shocks) have different spring rates and subsequently different valving behavior.

But you can valve a big shock lightly.

 

[Jgunner]

No, different diameter shims (for different size shocks) have different spring rates and subsequently different valving behavior.

But you can valve a big shock lightly.

Got ya. I only have experience with a arms and mid mount 4/3 links, never directly to an axle.

 

[nukegoat]

Got ya. I only have experience with a arms and mid mount 4/3 links, never directly to an axle.

That is good experience! The right kind.

 

[snivilous]

So the 80 is now gone as of today The frame got taken away to scrap. I cut up the cage to salvage the pieces of steel I wanted. Parts of it will live on in the 4800 Rock Lizard. Which if anyone is curious about, I got the chassis kit last week! I am finishing up my buddy's 4600 cage on his 4runner so a week from today I should start building the new buggy. A lot of plans changed too, and yesterday I picked up a 6.0 lq4 and 4L80, so this little 3000-3500lb buggy will be getting pushed by a modest 400hp ideally. Also grabbed some Hellfire knuckles that I will be using with the front diamond axle, and then also grabbed another TK1 sway bar for the front end.

So as of this instant it'll be a 1.75" tube chassis, 114" wb or so, diamond housing front and rear, all "stock" FJ80 components with chromos/hellfires/9.5s/etc, full hydro, lq4/4l80 with some bolt ons, np205, 2.5x16s front, 3.0x16 rear with 48" trailing arms, 37s, etc.

Super excited to get working on it, though it's slowly going from being a "budget" build to going slightly balls to the wall. But I'm super excited! Hopefully be together by April/May and ready to run a few races

 

[darthyota]

So are you keeping any of the fj80 frame so you can keep a vin on the chassis?

 

[snivilous]

So are you keeping any of the fj80 frame so you can keep a vin on the chassis?

Yes, I'm literally keeping like 6"x2" where the VIN was and that's it haha. You need a VIN inspection here (only thing needed to register a vehicle) so we'll see if the cops throw a fit about it.

 

[snivilous]

So everyone I've talked to has screamed at me for how bad of an idea toyota axles are, and if I'm gonna build a buggy may as well build a buggy and not skimp out somewhere and constantly be breaking. So I'm starting to look into 609s, leaning towards spidertrax gear but need to research more and save up some money.

So I'll have my brand new RCVs, brand new Nitros, and brand new Hellfires listed up pretty soon. As well as trying to get rid of all my spare shafts, drive shafts, spare hubs, etc. So if anyone is interested in any of that, let me know!

 

[darthyota]

keep it toyota do tundra 10.5 centres with d60 outers but ruff stuff and diamond make fabricated housings

 

[Ntgm37]

I read this originally in 18. I always wanted to check out the hammers, and i got to go this year. It makes sooooo much more sense now that I've seen the specific sections and the race up close. Sorry to bump an old thread, but what are you up to now?

 

[cruiseroutfit]

I read this originally in 18. I always wanted to check out the hammers, and i got to go this year. It makes sooooo much more sense now that I've seen the specific sections and the race up close. Sorry to bump an old thread, but what are you up to now?

Come hang our with Rusty Nail Racing next year. Tons of Cruiserheads supporting racers.

 

[snivilous]

I read this originally in 18. I always wanted to check out the hammers, and i got to go this year. It makes sooooo much more sense now that I've seen the specific sections and the race up close. Sorry to bump an old thread, but what are you up to now?

That's awesome! I've been going every year since, and still regret chopping the 80 up. I helped build a 3rd gen 4Runner that had a short stint at KOH in 2019. I've helped pit for Amber Turner #468 in her Samurai every year that she's raced. Last year I codrove for Jason Berry in a UTV for KOH and made it through a few rock trails before timing out, and also codrove with him for the Moab and Prairie City race until he wadded the UTV up.

As far as me personally, I bought my first house at the end of 2019 and started building a 4400 (unlimited) style buggy. I learned a lot from the 80, and a lot of what I wanted. Though this has been an extremely long process since I've built and tried everything I can do myself. It's driven around a little but I'm thinking this year it'll be finally drivable and huge MAYBE race at KOH next year. It's more meant as a play car (I live close to Sand Hollow in Southern Utah) and yet will be race legal. I don't have the time or money or want to hit all the races, but would like something to race if I want to.

The two things I wanted that the 80 couldn't deliver was handling, and more power. So that's what I've tried to focus on this. I tried to keep it as low as possible and handle good, and have plenty of power. It originally started as a Rock Lizard chassis but the only part I really kept was the boat sides. It's 1.75" tubing mostly, 119" wheel base, weighs around 4000lbs (about 2000lbs less than the 80, another big thing I wanted), on 40s but will fit 42s, super duty axles, 35 spline front, full hydro, bypasses and coilovers, trailing arm, currently has a 5.3 LS with a LSA supercharger after I blew up a 6.0 LS that was originally in it--that is now waiting in boxes to be rebuilt into a 6.7 (408) stroker with the LSA supercharger, that is mated to a 4L80e 4-speed trans and a 3:1 race atlas.

I've built, designed, cut, welded every single part on this. Learned how to tig weld, so about half the chassis is mig and then I learned tig and have done that ever since. Built the exhaust myself, built the engine, driveshafts, etc. Tried to do every thing myself. The last bits which I'll buy soon is lockers and gears, a floor, and need to wrap up the wiring and hydraulic line routing.


The buggy is a very slow project. My other project that I've spent more time on lately is a 1978 Hilux I bought last year for $300 with no engine, and swapped a 2JZ into behind a 6-speed manual out of a 350Z. If you want to read about that: Hilux - 550hp 2JZ 1978 Hilux Build - https://forum.ih8mud.com/threads/550hp-2jz-1978-hilux-build.1278258/

And otherwise, I have some other Toyotas that are lesser of projects, but really the buggy is the follow on to the 80, and the Hilux is the parallel build with the buggy that is meant for the streets. Long answer to a short question

 

[Ntgm37]

Come hang our with Rusty Nail Racing next year. Tons of Cruiserheads supporting racers.

Yeah, I'll be going every year now. It was awesome to see it. I learned a lot in the first go so i will be way more prepared and will have a rzr or my 80 with me to mess around in.

 

[Augustiron]

This was a great read of a great adventure.

Worthwhile bump...