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Future of KOH 4400 chassis/car development?

Exactly.

Everyone talks about how the IFS cars are better in the desert and the live axle cars are better in the rocks, but they totally miss how fast the IFS cars are in the nuisance rocks.

Watch Scherer going through his last trail, how fast that car is going and how smooth it is over the nuisance stuff.

A couple of shots of the few IRS cars was impressive also.
 
Everytime Baja trucks increase tire size, the overall weight goes up, which is why those pigs weigh 6500lbs or more.
They are also faster than the smaller ones.
What is your point?

Same with U4, Jason's car looked big and I'd be curious to see what it weighed compared to Raul's car, I'm betting at least 1k more.
I'd be ready to bet on the opposite. UFOs are pigs.
Joe Thompson said he could make them a lot lighter but the Gomez are beating the shit out of them and that's why he has to keep them heavy.

Jason Scherer is a lot easier on the cars which I think enabled a lighter car overall.

Kinda amazed the engine lamed up on him, it seems like the engines are the most developed parts of non-SxS 4400's, (and not withstanding Campbells), should be reliable for a race of this length.
Lots of engine issues all around. Not just Campbell's.
 
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I mentioned in the koh thread that I'd be curious to see a SxS sized rig built from scratch. Maybe using a 4cyl automotive engine or maybe just use sxs parts. Solid axle f&r would be interesting, but realistically, ifs and solid rear seems ideal.

I heard someone mentioned that a solid rear axle yamaha yxz exists. I wonder if that would be plausible with a can am? Would be pretty difficult with where the engine is without making the wb long af.

Say a similar drivetrain to the current moon buggies, small turbo 4 cyl, 904, D300? Again, maybe the sxs stuff beats it on power to wieght.

Even if no one really goes that direction, I do wonder if some of the cars will end up with a narrower track width? Anyone know what the ufo and Jason's width is vs Lauren/Vaughn and some of the other spaceships?
My buddy did this 8-10 years ago. He took the Honda 4 cylinder motor mated it it to a hand built trans to make a awd super buggy.

He did this on low budget, sourcing most of the shit from junkyards.


He now has a machine shop making odd gearsets, limited slip carrier ect

 
I mentioned in the koh thread that I'd be curious to see a SxS sized rig built from scratch. Maybe using a 4cyl automotive engine or maybe just use sxs parts.
That sounds like it's a Polaris ProR you're describing.
 
If you look historically at the entire racing world, manufacturers have consistently changed the nature of a racecar by lightening it, increasing horsepower, changing suspension design.

There's no reason that couldn't happen here.

The biggest obstacle is money. There's simply no reason to have a multi-million dollar designed car here. So whatever happens, will happen on a budget, albeit, a bigger budget than I can afford
I think this might be why we eventually see a UTV win. They do have multi-million dollar development budgets, not directly for this race, but for the production vehicles. It's been said, and I agree, that the KOH UTVs are closer to production vehicles than not.

If you compare a 2013 Polaris XP900 to a 2023 CanAm X3, I'd say the increase in performance is greater than comparing a Bomber (2013 King) to a UFO car (2023 King). The Bomber is still competitive today with minor tweaks, the XP900 doesn't hold a candle to the X3 (and the X3 is due for a refresh). If this trend continues for another 10 years, we may see a UTV on top of the box.

There's a good chance the trend doesn't continue though. Look at sport bikes for example. Huge increases in performance through the 90s and 00s, with tapering gains today. I also stopped riding sport bikes, so maybe I don't know how much better a 2023 R1 is than a 2013 R1.
 
I think that I heard Schereeerererer was running Live Valve on his fox shocks. Any idea who else was running similar systems? Was that a factor in his speed through various terrains?

From wikipedia, here's the past 10 winners:
  • 2013: Randy Slawson and Michael Slawson[24]
  • 2014: Loren Healy and Casey Trujillo[25]
  • 2015: Randy Slawson and Michael Slawson
  • 2016: Erik Miller[26]
  • 2017: Shannon Campbell[27]
  • 2018: Jason Scherer[28]
  • 2019: Jason Scherer[29]
  • 2020: Josh Blyler[30]
  • 2021: Randy Slawson and Dustin Emick
  • 2022: Raul Gomez
  • 2023: Raul Gomez
So going backwards, it's IFS, IFS, SA, SA, IFS, IFS, IFS, SA, SA, IFS, SA for wins. So 6-4 IFS to Solid axle.

I remember that when IFS cars were starting to become popular (Baird, Campbell, others) that people all claimed IFS was going to replace SA. We definitely see the benefit in the desert, but the SA close up the gap in the rocks. Any mistake by an IFS car, and there's usually a Bomber or Miller chassis there looking to climb on the top step.

I believe one day UTVs could be in that convo, but I still don't see anything becoming dominant to the point of making something obsolete.
 
I think that I heard Schereeerererer was running Live Valve on his fox shocks. Any idea who else was running similar systems?
Horschel and the Fun Havers had Fox Factory supported Live Valve.
A couple of others had retrofitted units too.
 
To me, the successful 4400 rigs are just bigger SXS's. And no stock geometry SXS would ever run close to a thought out 4400....nor those SXS's that finished.
I'm listening to post race interviews and Hunter Miller said their 4400 Can Ams still run factory chassies and geometry...
 
Anyone see this new SCS setup scherer is running? Much better setup than a typical SCS with angled driveline. And I am thinking the big hunk in the middle maybe has something to do with a reverser for the rear to match rotation of the portals up front. Also possible that it has lower gearing at the rear output to compensate for the reduction difference with the portals up front so the same third member gear can be used? I have always thought there could be more development in the tcase area with these ultra4s and it seems like SCS is really stepping up. I think it is wild that Jason has this single speed setup doing so well in the rocks and desert. I would imagine this is hell on a trans though. Anyone catch how fast he was doing in the desert? I know slawson has done this for a while with the 4l80 but he also still runs an atlas so he has the option to shift into low for the big rock stuff.

scherer.PNG
 
Mason has something similar but different on their AWD TTs
 
..... Any mistake by an IFS car, and there's usually a Bomber or Miller chassis there looking to climb on the top step......

That's the key right there. The IFS cars have to fail or make a mistake before a live axle car wins.

That said, Slawson and Miller builds good solid cars and they both know how to prep a car and drive, so they will always be a threat. And it's looking like we need to add the Bylers to that list of good car prep and drivers too.
 
I believe there are multiple variants out there, but I recall a Shock Therapy video where they had a full chromo race chassis that met whatever desert promoters rules; but added lots of strength over the weld in chassis stiffeners.

This variant is ZRP's:


I wanna say that Brenthel or another TT chassis company had one as well. So the question is, when they say stock chassis do they mean something like this?
 
That's the key right there. The IFS cars have to fail or make a mistake before a live axle car wins.

That said, Slawson and Miller builds good solid cars and they both know how to prep a car and drive, so they will always be a threat. And it's looking like we need to add the Bylers to that list of good car prep and drivers too.

Miller is Blyler is Miller, right? Since Blylers build the Miller spec chassis, they are getting them wholesale. :laughing: But they do take their prep seriously. I was impressed that Rusty was outpacing Josh for the first 2 laps.

It's key that SA cars are having to catch up in the current format because they use the desert loop to get early attrition to hopefully prevent the outer limits or aftershock bottle jams from years earlier. IFS has so far shown the superiority in the desert and nuisance rock.
 
Anyone see this new SCS setup scherer is running? Much better setup than a typical SCS with angled driveline. And I am thinking the big hunk in the middle maybe has something to do with a reverser for the rear to match rotation of the portals up front. Also possible that it has lower gearing at the rear output to compensate for the reduction difference with the portals up front so the same third member gear can be used? I have always thought there could be more development in the tcase area with these ultra4s and it seems like SCS is really stepping up. I think it is wild that Jason has this single speed setup doing so well in the rocks and desert. I would imagine this is hell on a trans though. Anyone catch how fast he was doing in the desert? I know slawson has done this for a while with the 4l80 but he also still runs an atlas so he has the option to shift into low for the big rock stuff.

scherer.PNG
Jason Berger was on the Wheeling Wine and Whiskey podcast, and he sad the entire purpose of the weird SCS box was to allow them to lower the passenger seat to get more head room. Jason Berger isn't a short guy.
 
On the topic of new tech, I think a locking 1 way drive for the front output of the t-case eventually happen and be another improvement.

Quinn from 74Weld was talking about this on a different podcast (Truck Show maybe?). He hypothesized that one of the issues they're having is the front tires are being pushed into whoops by the back tires, and that puts extra stress on the drivetrain. A 1 way diff in the front output would fix that, but it would then only be 2wd in reverse, so you'd need to lock it out in reverse.

Random thought. I think people are more open to talk about details like this on a podcast rather than a forum, social media, or YouTube because it's pretty little work for them, they don't need to take photos, write/edit text, and then deal with comments. As a podcast guest, you can just BS about what you're doing and your ideas, and the podcast host does all the production and deals with any further feedback.
 
On the topic of new tech, I think a locking 1 way drive for the front output of the t-case eventually happen and be another improvement.

Quinn from 74Weld was talking about this on a different podcast (Truck Show maybe?). He hypothesized that one of the issues they're having is the front tires are being pushed into whoops by the back tires, and that puts extra stress on the drivetrain. A 1 way diff in the front output would fix that, but it would then only be 2wd in reverse, so you'd need to lock it out in reverse.

That's already implemented in the Mason AWD TTs

I wanna say that Brenthel or another TT chassis company had one as well. So the question is, when they say stock chassis do they mean something like this?
I know for sure that the CanAms started life as production vehicles. Their fabricator posted the builds on IG.
 
On the topic of new tech, I think a locking 1 way drive for the front output of the t-case eventually happen and be another improvement.

Quinn from 74Weld was talking about this on a different podcast (Truck Show maybe?). He hypothesized that one of the issues they're having is the front tires are being pushed into whoops by the back tires, and that puts extra stress on the drivetrain. A 1 way diff in the front output would fix that, but it would then only be 2wd in reverse, so you'd need to lock it out in reverse.

Random thought. I think people are more open to talk about details like this on a podcast rather than a forum, social media, or YouTube because it's pretty little work for them, they don't need to take photos, write/edit text, and then deal with comments. As a podcast guest, you can just BS about what you're doing and your ideas, and the podcast host does all the production and deals with any further feedback.
Not sure if it is lorens first triton portal car or the most recent ifs/irs car but I am pretty sure I saw it mentioned somewhere that he is running an xtrac tcase that has a differential that can be locked/unlocked. I have tried to find more info on it but havnt been able to.

This is the same thing that I have always thought could be helpful in the desert then lock up in the rocks. Not sure if it is one way locking or what but robby woods has a tcase with a differential in his MMD truck that he came up with. The mason AWD trucks also have the same thing going with their front diff/tcase they build but as you mentioned, it cant be locked so 2wd in reverse.

I feel like something with the same concept as the old jeep 242 cases that came in cherokees with part time/ full time 4wd could be used just on a much beefier scale. It is just a lockable differential that can split the drive bias letting you drive in 4wd on slick roads without as much bind when turning.
 
I feel like something with the same concept as the old jeep 242 cases that came in cherokees with part time/ full time 4wd could be used just on a much beefier scale. It is just a lockable differential that can split the drive bias letting you drive in 4wd on slick roads without as much bind when turning.
There was a guy on the old board that did a lot of development on a LT230 TCase for that reason.
Can't recall the name. SXOR rear engine chassis.
 
What's interesting is that Marcos and I think now JP have that crazy IRS with the diff on the pass side cv axle. The rumor is that they went to Joe Thompson and asked for a v8 sxs on 40s :laughing:

I think rauls success over the other 2 is pure driver. I don't think JP will ever keep a car together enough to win, he's too cocky:laughing: I'm not sure about Marcos though.

The 4ws on the lamBRO is an interesting idea to help with the shear size of it in the rocks. Although, it obviously hasn't worked out :laughing:
As far as Joe Thompson, GBR didn't just have him design & build a car, they made him a deal so good Joe works for them full time. Him and Fishmouth Fabworks now work for GBR full time. These cars have been advancing since their debut 6 years ago, when they were sponsored by ProComp! GBR has invested and worked hard over those years to improve reliability of their cars and also their pit crew and staff. Them getting a clear back-to-back KOH win is astounding, but it comes from an approach of finding what the weak points are and engineering a proper solution. Not sticking to a "tried-and-true" type of thinking like many top builders do (Miller, Campbells, Slawson, etc.), they aren't afraid to advance their programs or methodologies. They have done lots research with portals, but have yet to make the jump due to reliability concerns.

They are now looking at making their own AWD Trophy Truck platform and I can't wait to see what Joe Thompson does in that arena.

The same drive for advancement can be said for Scherer. Keith Beam built an amazing chassis. The front suspension and drivetrain on his new car is cutting edge, no IFS has better travel, steering, and clearance. But he had to have a PERFECT day in order to be able to win. His 2nd place finish can either be attributed to his flat tire, a poor line choice in Kings Veto, or not pushing hard enough on Lap 2. Jason has quite an edge with his competitive mindset, his team's experience, and his desire to examine every part of his program. Jason was testing and tuning his live-valve programming seemingly every other week since December, leading up to Hammers. He logged the fastest time for Lap 1, even beating the UTVs. And he was beaten by seconds.

We are talking about two competitors who can internally develop and advance the sport. It's nothing short of amazing.

I make the "tried-and-true" comment about other multi-time Kings for three instances this year that hurt each one: Shannon Campbell's qualifying lap was stunted by one of his mechanical relays for his fuel pumps resetting when he bottomed out on the ridge, took him a bit to diagnose the issue, which lead him to overdrive his car and roll at the top of the last hill; Miller's car also had an electrical gremlin pop up in the race because of his desire to run mechanical relays in his overhead control board, similar issue to Campbell's; and finally Slawson was running his normal break-neck pace only to be hindered by a failed chassis-side upper link mount. The pace of the race has gotten to the point where these small issues are make or break, if you want to win. I am curious to see just how these three will address these issues as they are hard competitors.

The guy I want to be? John Webb, dude is there to blast his favorite tunes, ripping up JV in his bad-ass IFS. Guy nearly always finishes every year and he got 10th overall in an older IFS rig. His program is one that I think any of us could put together.
 
I believe there are multiple variants out there, but I recall a Shock Therapy video where they had a full chromo race chassis that met whatever desert promoters rules; but added lots of strength over the weld in chassis stiffeners.

This variant is ZRP's:


I wanna say that Brenthel or another TT chassis company had one as well. So the question is, when they say stock chassis do they mean something like this?

The Miller boys started with stock Can-Am chassis and had S3 Powersports modify them. They are not using 1 off cromo chassis. Take a good look at the pictures Hunter Miller texted me of their KOH chassis I posted on page 1 of this thread and it's blatantly obvious that it started life as a stock chassis.
 
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This is a fun read for a KOH fanboy/nerd. I still want to see Randy be the first 4th time king. It’s not impossible yet!!
 
Shannon Campbell's qualifying lap was stunted by one of his mechanical relays for his fuel pumps resetting when he bottomed out on the ridge, took him a bit to diagnose the issue,[...] Miller's car also had an electrical gremlin pop up in the race because of his desire to run mechanical relays in his overhead control board, similar issue to Campbell's
This blows my mind.
When you know how much better PDMs are...

The guy I want to be? John Webb, dude is there to blast his favorite tunes, ripping up JV in his bad-ass IFS. Guy nearly always finishes every year and he got 10th overall in an older IFS rig. His program is one that I think any of us could put together.
Nailed it !
 
On the topic of new tech, I think a locking 1 way drive for the front output of the t-case eventually happen and be another improvement.

Quinn from 74Weld was talking about this on a different podcast (Truck Show maybe?). He hypothesized that one of the issues they're having is the front tires are being pushed into whoops by the back tires, and that puts extra stress on the drivetrain. A 1 way diff in the front output would fix that, but it would then only be 2wd in reverse, so you'd need to lock it out in reverse.

Random thought. I think people are more open to talk about details like this on a podcast rather than a forum, social media, or YouTube because it's pretty little work for them, they don't need to take photos, write/edit text, and then deal with comments. As a podcast guest, you can just BS about what you're doing and your ideas, and the podcast host does all the production and deals with any further feedback.

AWD is where it will progress to. Not sure all the variables it will take to make it perfect, but I believe that's where it will be headed.

As far as Joe Thompson, GBR didn't just have him design & build a car, they made him a deal so good Joe works for them full time. Him and Fishmouth Fabworks now work for GBR full time. These cars have been advancing since their debut 6 years ago, when they were sponsored by ProComp! GBR has invested and worked hard over those years to improve reliability of their cars and also their pit crew and staff. Them getting a clear back-to-back KOH win is astounding, but it comes from an approach of finding what the weak points are and engineering a proper solution. Not sticking to a "tried-and-true" type of thinking like many top builders do (Miller, Campbells, Slawson, etc.), they aren't afraid to advance their programs or methodologies. They have done lots research with portals, but have yet to make the jump due to reliability concerns.

They are now looking at making their own AWD Trophy Truck platform and I can't wait to see what Joe Thompson does in that arena.

Joe is definitely pushing that envelope and it is awesome that GBR is helping him get in that direction. Huge kudos to all those guys.

The same drive for advancement can be said for Scherer. Keith Beam built an amazing chassis. The front suspension and drivetrain on his new car is cutting edge, no IFS has better travel, steering, and clearance.

Yes, that IFS is more advance than any other car, BUT, let's get this out in the open LOUD and CLEAR, as great of a car that Jason has, Keith had no involvement in the design of the IFS, all he did was weld it together and get it into the car. The design is from the same engineer that designed both of Scherer's other two IFS cars, Dallas Lund. He gets it, more than any other person in the IFS world. Yes, I am biased.

The IFS in J's old car is still more advanced than any others in the game, you can see it just by watching videos of all the different IFS cars in action.


But he had to have a PERFECT day in order to be able to win. His 2nd place finish can either be attributed to his flat tire, a poor line choice in Kings Veto, or not pushing hard enough on Lap 2. Jason has quite an edge with his competitive mindset, his team's experience, and his desire to examine every part of his program. Jason was testing and tuning his live-valve programming seemingly every other week since December, leading up to Hammers. He logged the fastest time for Lap 1, even beating the UTVs. And he was beaten by seconds.

Or his 2nd place can be attributed to engine gremlins.

When he hit the lakebed and he was only doing 75mph, you know something was holding him back.
 
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The design is from the same engineer that designed both of Scherer's other two IFS cars, Dallas Lund. He gets it, more than any other person in the IFS world. Yes, I am biased.
You're including the TT guys too?
 
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