Backspace equals one half the wheel width and in this case add the positive offset to get it. I am too lazy to convert but 9.5"/2+18.5mm
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Wheel Specs?
Basically all I know is they are 20 x 9.5
Anybody know where I can find our stock wheels
Backspacing
Offset
Lug Spacing
Weight
Thanks
Anybody know where I can find our stock wheels
Backspacing
Offset
Lug Spacing
Weight
Thanks
1 - 18 of 86 Posts
If the offset is negative you subtract it. The backset is the distance from the inside wheel face to the mounting surface.
^ I am with ya. Let me guess that is the Bravado site? If so I agree those numbers are so strange I moved on. I am at about at my wits end. I have been shopping for three hours for ANY manufacturer that offers anything not custom in a 9.5" front and a 11" rear that works! I think I have changed my mind, may want black and not chrome but I can't find anything that works at least off the shelf. I know those Bravado's works because there is a thread where a member used them. I have a question or two out on email now.
FYI, I do think that 25 mm may be close to the magic rear offset for an 11". We know a 21mm offset works with a 315, because that is the Bravado thread. I am about to pull the trigger, but can't find anything to buy!!
FYI, I do think that 25 mm may be close to the magic rear offset for an 11". We know a 21mm offset works with a 315, because that is the Bravado thread. I am about to pull the trigger, but can't find anything to buy!!
So the more positive offset the more it sets back into the car. I have the 305's mounted up. Keeping the same offset at 18.5 mm with a wider wheel keeps the tire in the same realitive place. Notice that there is 5/8" distance from the face of the 9.5" wheel to the outside edge of a 305. Coldheartid has a 21mm offset, shifting it in just a bit. He reports even with those huge 325's he still has some room at the critical spot inside. I think I am going to go with 305 rears. So IMO a 25mm offset will work with either a 10.5 or an 11" and tuck the package in as far as we dare. On the backs only now.
I believe we are saying the same thing, we but we are a critical 5mm apart in opinion. I personally have passed only a 5/8" short rod between a 305/35 on the OEM wheel and the tightest spot on the front side of the rears where the "rib" is. I will go 1/4" closer with a 25mm offset, but you are suggesting 1/2" closer. I would encourage you to double check clearance with a 30 mm offset no matter what size width wheel you choose. An 11" wheel, a 10.5" wheel and a 9.5" wheel all put the same size tire 1/2" closer to the inside with a +12mm offset change.
You are correct. That is why I posted the charts. Your missing my point. The TIRE POSITION. Since we have 5/8" play inside the tire edge it is nearly pointless to talk about the wheel position. What is important is that you better double check the severe offset....you all do what you want. If a 30 mm offset works with a 315 you would make my day, go for it.
Driver72 you do get it and I will respond to you. I understand the offset/backset. I did not work in a tire shop and instead received an engineering degree, with a math minor. The poster above is correct the math is right. He is wrong when he says no need to check however. I was also a carpenter and now direct large construction. Check and re-check your measurements!
Now one more time. This concerns the backs only. I would not mess with the front, go for some 9.5's and leave the spacing alone. Don't get me wrong, if we could stuff the wheels and tires back in there 40 mm I would be happy, but there is a hard problem we can't move. It is located on the front inside. It looks like a rib in the liner. Coldheartid reports his large 315's on the 11" with ONLY a 21mm offset is close. He posted he can run his finger btw the tire and the hard surface.
1. I have 305/35 mounted on the OEM 9.5's. I can move a 1/2" rod between the hard surface and the TIRE.
2. I posted pictures for everyone showing 1- edge of a 305 on the outside is dead even with the sheet metal on the top. And 2- the 9.5" wheel edge is 5/8" inside of the outside edges of the 305, it will be a bit worse or greater with a 315. Now I don't care if you want to be anal with the outside edge of the wider wheels but the tire really conceals it. Besides the problem is that when you talk about offset you are moving the centerline of the TIRE/wheel. In this case we can only move that tire/wheel assembly so far before it will rub the inside.
3. Considering ColdheartId comments and his wonderful job of pioneering and finding nearly the only off the shelf wheels that work along with my measurements AND I don't give a damn about where the wheel edge sits. I think we can order a 25mm offset with some 305's and they won't rub. I am not ready to say another 5mm or 1/4" (30mm) works. I really have my doubts you can fit a 315 with a 30 mm offset. You may get a 305 at 30 mm, but I will let someone else try it for me.
I want to be wrong on the prediction. I am not wrong on the relationships and offset/backset. Anyone who is selecting their own equipment better be able to read those fundamental dimension charts like I posted yesterday and not just pick offset numbers because they are even numbers unless your retailer has a generous return policy.
Now one more time. This concerns the backs only. I would not mess with the front, go for some 9.5's and leave the spacing alone. Don't get me wrong, if we could stuff the wheels and tires back in there 40 mm I would be happy, but there is a hard problem we can't move. It is located on the front inside. It looks like a rib in the liner. Coldheartid reports his large 315's on the 11" with ONLY a 21mm offset is close. He posted he can run his finger btw the tire and the hard surface.
1. I have 305/35 mounted on the OEM 9.5's. I can move a 1/2" rod between the hard surface and the TIRE.
2. I posted pictures for everyone showing 1- edge of a 305 on the outside is dead even with the sheet metal on the top. And 2- the 9.5" wheel edge is 5/8" inside of the outside edges of the 305, it will be a bit worse or greater with a 315. Now I don't care if you want to be anal with the outside edge of the wider wheels but the tire really conceals it. Besides the problem is that when you talk about offset you are moving the centerline of the TIRE/wheel. In this case we can only move that tire/wheel assembly so far before it will rub the inside.
3. Considering ColdheartId comments and his wonderful job of pioneering and finding nearly the only off the shelf wheels that work along with my measurements AND I don't give a damn about where the wheel edge sits. I think we can order a 25mm offset with some 305's and they won't rub. I am not ready to say another 5mm or 1/4" (30mm) works. I really have my doubts you can fit a 315 with a 30 mm offset. You may get a 305 at 30 mm, but I will let someone else try it for me.
I want to be wrong on the prediction. I am not wrong on the relationships and offset/backset. Anyone who is selecting their own equipment better be able to read those fundamental dimension charts like I posted yesterday and not just pick offset numbers because they are even numbers unless your retailer has a generous return policy.
Thanks. Yes the wheel selection while vast leaves just a few for us now, off the shelf anyway. IaCat ordered a 25mm offset with a 10.5" width. He is also going to try to fit up some 315 Invo's. He is the man of the hour right now. I am going to wait until he gets that. I may even make a one hour trip out of my way to personally see how it looks! He happens to be within a hour of a frequent business destination.
The 25 mm offset places the outside face of the wheel just 1/4" farther out than the 9.5" sits. Going to have the big tire drawing most of the attention. Hoping the little more tuck makes a difference we can see. Hope he scores in the next couple of weeks! Good luck to you too.
The 25 mm offset places the outside face of the wheel just 1/4" farther out than the 9.5" sits. Going to have the big tire drawing most of the attention. Hoping the little more tuck makes a difference we can see. Hope he scores in the next couple of weeks! Good luck to you too.
What is ResumeSpeed's last projection for delivery for you? You have to be one excited man right about now! I was in your neighborhood with the Cat last week too bad I was not a week later, we could get a feel for fit quick.I just received my gloss black MRR HR6 rims with Nitto Invos.
Rear - 20x10.5 +25mm 315/35/20 69lbs
Front - 20x9 +20mm 275/40/20 61.5lbs
My car's still sitting at the damn rail yard though...
I took the plunge with Triumph. Same rear as you, identical 9.5" front to the OEM.
Hey you guys clean the stock wheels yet?? What a pain. Anyone considering ease of cleaning with new wheel picks? I got the same basic style but with five spoke arrays instead of the OEM seven. I know between sprays I can get my hands between the spokes to wipe the wheels down inside the rim with those.
In Council Bluffs I bet. The invisible Fenkell inspection process. We are pretty sure besides catching the lower radiator clamp (good catch) they or someone attempted a pretty crappy fix of a dent in the door. You make sure you look the car over real well before leaving the dealer. Bring others!
Have to give credit to Billet Hellcat, he found them. My finish is NOT matte black. I am going to try something different. Hope it all works!What Triumph wheel did you get?
Triumph Performance Wheels monobloc 6061-T6 Ordered SRT Hellcat Forum
^. The other major item I like about the Triumph deal is retaining the 9.5" front and not compromising down to everyone's little 9" wheel. I want to retain the front geometry entirely.
^ yep you and me are thinking the same stuff. I am pretty excited to see how the 315's with a 10.5" wheel can grip. I am going with the P-zero. Enough is enough, I have two new fronts in the garage, but, darn those are some spendy rubber pieces for the back. Now that we have some times it will be interesting if those can match the DR's on the street anyway.
I have no idea. I would not. Looks?Why do guys downsize the front wheel to a 9 unless it’s strictly a tracked car?
True, all four wheels/tires on OEM interchangeable.I've read through this entire 5 paged Post/Topic and I don't see anywhere, someone sharing that the Front Offset of our Stock(2016 Chllngr Cat) has a different Offset than the Rear. So, they are the same I must presume?
1 - 18 of 86 Posts
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