Is this legal for the Pro Production class?

[NIKAL]

I think most agree that chassis suspension points is one of, if not the most important rule in the Pro Production Class.

So while looking at the feature of Polaris CMO Craig Scanlon's new Holz built UTV, I noticed a few things that stood out. I know he had been racing the last few races of the 2016 season in the Unlimited class and suspension points can be moved. But now see he changing classes and running the Pro Production Turbo for 2017. But I dont think his car is legal for Pro Production after looking at pictures of the front upper arm mounting location?

http://www.utvunderground.com/featu...rsports-group-polaris-rzr-xp-turbo-43101.html
http://www.utvunderground.com/featu...rsports-group-polaris-rzr-xp-turbo-43101.html

After looking at this picture;

You can see the upper a-arm mounting point, looks to have been moved forward a several inches from where the stock a-arm mount would be. I'm guessing they did this to clear the front steering rack & tie rods? Plus the two a-arm frame tabs look much closer together vs. the width of the stock chassis tabs.


Look at how much closer the front a-arm is to the front dif on this stock chassis. You can clearly see that Craig's cars a-arm was pushed forward to make room for tie rod clearance as the suspension cycles.


Will Corey allow this to pass pre-tech for the Pro Production Turbo class at the Parker 250?

 

[///Airdam Clutches]

I am definitely not one to cite the rule book as I do not know it. I do know the rule about chassis mounting points but if I remember correctly it's only the lower A-arm mounting location that had to remain intact. This is why almost every team uses the stock lower rails. Everything from the lower rails up can be hand fabricated. The upper arm and shock mounts do not have to remain stock. I only remember briefly going over this when asking about Burnett's car last year. Because Reid researched the rules to see what he could get away with in order to maximize the efficiency of the suspension. If I remember correctly he moved the upper arm mount and shock mounting locations.

You would definitely have to dig deeper in the rules. I think the stick pivot points definition in the rules applied only to the lower arm mounts.

 

[ssb4]

UTV-5 SUSPENSION:
Pro Turbo Production and Pro Production UTV classes: All suspension mounting points must remain the stock design and in the stock location and position as delivered from the manufacturer, however they may be reinforced for strength. No suspension mounts may be moved, added or removed. Any A-arm suspension point that uses only one bolt to mount the A-arm , may be changed to a 2 bolt mount design. Either side of the original pivot points may be used to remount the 2 suspension points.

Unlimited UTV class suspension: Is open. Any placement is allowed. Any type of suspension is allowed. Any design of suspension is allowed.


Sent from my iPhone using Tapatalk

 

[NIKAL]

Airdam the rules as shown above state all suspension pivot points must remain Stock for the Pro Production class. That rule seems to be the "heart" of the UTV class rules. Unless the photo above was taken with some crazy camera lens, the chassis was extendended forward so that arm could be pushed forward to clear the rack and tie rods, plus I bet it helps hugely with geometry. Shock mounts are open in all UTV classes, and I know Reid was all about better motion ratios.

Didn't Holz build two or three cars like this one?

 

[cocojoe]

Clearly an unlimited car by the rule book, but we will see what the powers decide

 

[tatum]

If it is just moved forward to the front side of the mounting tab and another tab added then no geometry would be changed and IMHO should be legal.

 

[///Airdam Clutches]

it appears they moved the upper A-arm forward to be able to clear the shock that now mounts to the lower A-arm. and likely changed the caster and other things by doing this as well. i was on the cell last night and couldnt distinguish what the picture showed. but today on computer it looks fairly clear.

 

[cocojoe]

The rules seem pretty clear, "in the stock location and position as delivered from the manufacturer" "No suspension mounts may be moved" Period. but the people that control the sport can allow some to bend the rules and force others to follow. Just the way it is.

 

[tatum]

It says in the rules above either side of the original mounting points may be used.

 

[cocojoe]

Not sure what that even means

 

[cocojoe]

does it mean that you can use either of the pivot point tabs, there by moving the pivoy point forward by only using the stock fowrad tab location or aft by using the rear tab location?

 

[NIKAL]

It says in the rules above either side of the original mounting points may be used.

I believe that is if it's a single bolt / single shear tab, like the 800 & 900 upper front a-arms chassis tabs were. They allowed you to add a second tab to make the arm a two bolt mounting system. On the 1000, the upper arm chassis tabs were two bolt / double shear at all pivot points.

Even if this was the case, the Holz car looks moved forward much more then the back side of a tab width.

 

[cocojoe]

Seems cut and dry, and a quick measurement at tech will solve the problem and decide what class the car runs in.

 

[NIKAL]

After looking some more, to me it looks like the lower arm pivot points might have been manipulated? Again maybe camera angle? Look at the lower arm front pivot point vs the dif location. Then look at the stock picture below. Does it look like the front arm mount was moved forward, or was the dif moved back??

 

[cocojoe]

Could be camera angle, but it does appear that the lower forward pivot point in the stock location is aft of the forward edge of the front diff, in the photos of the race car it appears that the same pivot point is forward of the forward edge of the diff, once again if this is the case then it is clearly an unlimited car and should run as such, I'm sure the owners and tech officials will have no problem doing the right thing and running it as such.

 

[tatum]

I just measured a stock one in camp and the backside of the upper mount is about an inch in front of the front side of the lower mount. The upper pivot mount is about 2.25 wide so it could be 3 plus inches forward and be legal as I am reading the rules. It really SEEMS to me that they are taking advantage of the rules as written, something that Nikal is always talking about people not doing.

 

[cocojoe]

Taking full advantage of the rules as written is what racing is all about, totally agree, what about the lower mount in relation to the front diff, was it also moved forward on the race car

 

[BiggJim]

Mark Holz has been building BITD cars a long time and understands the rules. With that said custom mounts can be made but must be approved and must maintain factory geometry...in other words the mounts must be in the same location as they were on the stock car. You are also allowed to make the arm wider and go to the outside of the original pivots. Back in the early days the teryx had a very short front load arm and was hard on pivot points. You could go to the outside of those pivot point and add a tab to increase arm width.

 

[cocojoe]

"long time" is a relative term, but that is a different discussion, it apprears that is what is going on here, the arm pivots appear to be using the forward mounting brackets as the now aft bracket, either moving the whole pivot locations forward or widening the pivot locations, and it appears that is legal

 

[NIKAL]

Just to clarify the chassis / suspension mounting point rules for the two Pro Production classes. I spoke with Cory, here is what he said the rules are.

Any suspension mounting point with a single tab on either side of the suspension component, using a single mounting bolt, may add a second mounting tab to the chassis, on either side of the factory original tab, thus allowing a double bolt mounted arm. You may not remove the factory tab, only add a second tab. This rule was put in place to add strength to a single bolt, single tab mounting point. Corys example was the XP900 upper front a-arm with its single tab on each side of the arm with one long mounting bolt.

Any chassis that comes with a two tab per suspension mounting point MUST remain in the stock location. You may add gussets or doubler plates to strengthen the original tab. You must mount the suspension part between the two factory tabs. Mounting a part on the outside of a factory chassis tab mount, or adding a 3rd tab is not allowed per the rules. The chassis tabs if replaced and Authorized by tech, must still be the same location & width apart as the factory mounts. So if using a hiem vs a bushing, you might have to add spacers to fill the spread of the two chassis mounts. The XP1000 and new X3 have two tab suspension mounting points from the factory, so there is no need to add a second tab.

Any chassis that has moved, altered or added extra suspension mounting points to the chassis is considered an Unlimited class UTV.

Moving of the front dif is legal. Moving the trans if not mounted directly to the engine is legal (The old Mav and new Yamaha run a trans that is not bolt to or supported by the engine) so those vehicles could move the trans as long as engine location is left stock. The new Can Am X3 and Polaris XP have the trans bolted to the engine, so those must remain in the stock location. Again front dif or drive shafts can be moved.