20x10 wheel on the front...

[1957 Chief]

Who is running them and what kind of drop do you have?
Backspacing?
Offset?

Looking to get 20x10's all the way around cause I can get better grip tires for autocross.

Thanks in advance,

Bubba

[Drummerboy]

Not sure you can run a 20x10 wide on the front with very much drop.

[1957 Chief]

Yea I know it gets tight. But its been done. I think the tubs have to be removed to make it work.

Bubba

[SCOTI]

I'm guessing here based on trucks I've dropped.....

A 15x8 Truck-Ralley wheel would be about 4" of BS. That puts the outside edge of the tire close to the fender opening/lip @ anything more than 4" of drop w/an average (for a truck) size tire @ 27-ish inches tall. Shorter tires yield more clearance but don't look 'right' (this of course is subjective).

So, given that as a starting point, you would need to go w/additional BS for wider wheels. On a 15" wheel you'll run into issues immediately. The 20" wheel will allow for additional BS but will still hit the a-arm once you exceed the 5-5.250" BS mark so trimming of factory arms will prob be required.

What 20" 'autocross' tires are you planning?
What will the suspension set-up be?

[1957 Chief]

Will most likely run the RE-71R Bridgestone if I go with 20's. Like you mentioned, a smaller tire doesn't look right. Right now I'm running tires that are a little taller than 26 inches.

For the suspension, I have the Ridetech coilover front and rear suspension, A-arms and swaybars. Running the Wilwood pro spindle up front with Wilwood brakes all the way around.

Bubba

[cruizin01]

Originally Posted by SCOTI

I'm guessing here based on trucks I've dropped.....

A 15x8 Truck-Ralley wheel would be about 4" of BS. That puts the outside edge of the tire close to the fender opening/lip @ anything more than 4" of drop w/an average (for a truck) size tire @ 27-ish inches tall. Shorter tires yield more clearance but don't look 'right' (this of course is subjective).

So, given that as a starting point, you would need to go w/additional BS for wider wheels. On a 15" wheel you'll run into issues immediately. The 20" wheel will allow for additional BS but will still hit the a-arm once you exceed the 5-5.250" BS mark so trimming of factory arms will prob be required.

What 20" 'autocross' tires are you planning?
What will the suspension set-up be?

I would agree. I have 8's with 4" BS. I wanted 9's but the cost to have 10's cut down was too expensive. If I were to run a 20x10 I would think a 0 offset or 5" backspace would be doable depending on tire height and how low the truck is.

[RADustin]

your loosing performance running rubber band tires if you plan on a 20" wheel with 26" tall tires. I'd look to run a slightly larger sidewall and a lighter wheel, so probably an 18".

also a 20x10 with 5" of BS is a -12.25mm offset. remember the wheel is 1" wider than advertised face to face, and BS is from the rear face. so 5" BS would be 6" of front space and the wheel mount face is 1/2" from center, back; so -12.25mm offset.

[1957 Chief]

Originally Posted by RADustin

your loosing performance running rubber band tires if you plan on a 20" wheel with 26" tall tires. I'd look to run a slightly larger sidewall and a lighter wheel, so probably an 18".

also a 20x10 with 5" of BS is a -12.25mm offset. remember the wheel is 1" wider than advertised face to face, and BS is from the rear face. so 5" BS would be 6" of front space and the wheel mount face is 1/2" from center, back; so -12.25mm offset.

Correct, the more I dig into this the more I realize that a 20x10 rim is pretty much unachievable unless I do some wheel tub modifications and what not.

I will attempt to run an 18x10 on the rear with a 5.00 backspace, an 18x9 on the front with a 4.50 backspace. Will run a 275/35/18 tire which is 25.6 inches tall, on the front and rear.

I talked to John at Ridetech and he said to check the swaybar for interference, so I might have to look at a diff front bar.

I know Jesse at Level & motorsports runs a pretty aggressive front tire/wheel as well, but his truck has the tubs removed.

Thanks for the conversations...

Bubba

[cruizin01]

Originally Posted by RADustin

also a 20x10 with 5" of BS is a -12.25mm offset. remember the wheel is 1" wider than advertised face to face, and BS is from the rear face. so 5" BS would be 6" of front space and the wheel mount face is 1/2" from center, back; so -12.25mm offset.

Yes you're correct. I mispoke.