tire/wheel combo for 2.5inch lift

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

chevy79_qa

Junior Member
Joined
Oct 2, 2022
Posts
23
Reaction score
17
Location
qatar
First Name
fidal
Truck Year
1979
Truck Model
k20
Engine Size
460 BBC
Hello everybody, I've got a 1979 Chevy k20 and got it lifted to 2.5 inches (skyjacker leaf springs and shocks) and wanted to get the biggest tire (preferably the widest) fitted without rubbing or trimming the fenders. The wheels I would love to install are 16x12's, but have no idea what BS I should look for without having knowledge about the tire size first. I would really appreciate your guys input and alternative wheel size recommendation's that I should look for to get that aggressive look. thank you all in advance. Here are some picture's of the rig:-


You must be registered for see images attach





You must be registered for see images attach
 

Rusty Nail

Full Access Member
Joined
Jan 29, 2015
Posts
10,041
Reaction score
10,133
Location
the other side of the internet
First Name
Rusty
Truck Year
1977
Truck Model
C20
Engine Size
350sbc
I had a two inch lift on 33s (15x8 rally) but I know a guy that runs 35s (15x7 rally) on a same truck, no lift.

Hmmm.....
 

chevy79_qa

Junior Member
Joined
Oct 2, 2022
Posts
23
Reaction score
17
Location
qatar
First Name
fidal
Truck Year
1979
Truck Model
k20
Engine Size
460 BBC
I know that by reading a lot of threads by now that 2.5 inch lift will accommodate 32’s and 33’s. Wanted to know if I can go wider than 16x10 wheels, and if not how wide can I go on the tires if the wheels are going to be 16x10’s, thanks anyways rusty nail.
 

Juggernaut

Full Access Member
Joined
Apr 11, 2021
Posts
212
Reaction score
233
Location
Illinois
First Name
Greg
Truck Year
78
Truck Model
K20
Engine Size
350
I have 35's on 17 x 9 rims, 4" suspension and 2" body lifts. Took the truck for a test drive yesterday and noticed a slight rub when turning hard to the right and driving into a deep ditch in 4wd. You may have problems with 35's depending on how you use the truck
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
6,970
Reaction score
12,220
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
Ho Lee Schitt! Beautiful truck! Nice work.
That out of the way, 33s is the largest practical size with a 2.5 lift imo.
I have a 4” lift on a K20 with 35s (sort of, 315-75-16s) and they don’t rub but have in the past and will rub under the right conditions.
Rim width is somewhat immaterial, as the tires are still the limiting factor.
Unless you’re going for the brodozer look which you aren’t with 16s, then 12.5 wide tires are sort of the widest practical tire.
Most “standard” rims for these trucks have about a 50% backspacing. IE 8” rims are 4” BS.
I think less than 50% back spacing makes them more prone to rubbing on the backside of the fender wells.
The axle placement exaggerates this. And there are offset spring perch plates to move the axle forward an inch or so. I haven’t done this but may need to once I have proper 35s on the truck.
Same considerations apply to yours.
See in this pic with wheels turned, front axle looks like it needs to be further forward.
You must be registered for see images attach
 

chevy79_qa

Junior Member
Joined
Oct 2, 2022
Posts
23
Reaction score
17
Location
qatar
First Name
fidal
Truck Year
1979
Truck Model
k20
Engine Size
460 BBC
Ho Lee Schitt! Beautiful truck! Nice work.
That out of the way, 33s is the largest practical size with a 2.5 lift imo.
I have a 4” lift on a K20 with 35s (sort of, 315-75-16s) and they don’t rub but have in the past and will rub under the right conditions.
Rim width is somewhat immaterial, as the tires are still the limiting factor.
Unless you’re going for the brodozer look which you aren’t with 16s, then 12.5 wide tires are sort of the widest practical tire.
Most “standard” rims for these trucks have about a 50% backspacing. IE 8” rims are 4” BS.
I think less than 50% back spacing makes them more prone to rubbing on the backside of the fender wells.
The axle placement exaggerates this. And there are offset spring perch plates to move the axle forward an inch or so. I haven’t done this but may need to once I have proper 35s on the truck.
Same considerations apply to yours.
See in this pic with wheels turned, front axle looks like it needs to be further forward.
You must be registered for see images attach
Thanks grit dog, so you think I should get 16x8’s and look for 33x12.5 tires? And also what is a safe BS number I should be looking for in that wheel I will be buying? Would really appreciate it .Thanks in advance.
 
Last edited:

shiftpro

Full Access Member
Joined
Aug 31, 2012
Posts
4,855
Reaction score
6,092
Location
BC Canada
First Name
shiftpro
Truck Year
73-87
Truck Model
1500, 2500, 3500
Engine Size
350, 383, 454, 496!
Ho Lee Schitt! Beautiful truck! Nice work.
That out of the way, 33s is the largest practical size with a 2.5 lift imo.
I have a 4” lift on a K20 with 35s (sort of, 315-75-16s) and they don’t rub but have in the past and will rub under the right conditions.
Rim width is somewhat immaterial, as the tires are still the limiting factor.
Unless you’re going for the brodozer look which you aren’t with 16s, then 12.5 wide tires are sort of the widest practical tire.
Most “standard” rims for these trucks have about a 50% backspacing. IE 8” rims are 4” BS.
I think less than 50% back spacing makes them more prone to rubbing on the backside of the fender wells.
The axle placement exaggerates this. And there are offset spring perch plates to move the axle forward an inch or so. I haven’t done this but may need to once I have proper 35s on the truck.
Same considerations apply to yours.
See in this pic with wheels turned, front axle looks like it needs to be further forward.
You must be registered for see images attach
Yes even 32" will meet metal if you twist it enough (and that doesn't mean a lot of twist).
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
6,970
Reaction score
12,220
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
Thanks grit dog, so you think I should get 16x8’s and look for 33x12.5 tires? And also what is a safe BS number I should be looking for in that wheel I will be buying? Would really appreciate it .Thanks in advance.
16x8s will work for 12.5 wide tires. Your current wheels look like they could be 8" wide. I prefer wider. 8" wheels 12.5" tires is a great off road setup, keeps the tires on the bead better at low pressure, but 10" wide wheels for 12.5 wide tires is about ideal IMO.
 

chevy79_qa

Junior Member
Joined
Oct 2, 2022
Posts
23
Reaction score
17
Location
qatar
First Name
fidal
Truck Year
1979
Truck Model
k20
Engine Size
460 BBC
16x8s will work for 12.5 wide tires. Your current wheels look like they could be 8" wide. I prefer wider. 8" wheels 12.5" tires is a great off road setup, keeps the tires on the bead better at low pressure, but 10" wide wheels for 12.5 wide tires is about ideal IMO.
10” wide wheels for 12.5 tire how tall can I go on the tire my friend ? I found a guy on the web who’s got 8” wide wheels except he’s running 11.2” wide tires can I do this with10” wide wheels? And if so will it be wider than his (when installing the 10” wide wheels with the 11.2” tires)? Thank you guys
 

Attachments

  • 17E61496-C7E2-4F3C-B97C-77F4C042E3DD.jpeg
    17E61496-C7E2-4F3C-B97C-77F4C042E3DD.jpeg
    93.4 KB · Views: 847

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
6,970
Reaction score
12,220
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
Like I said above, I wouldn’t go more than a nominal 33” tire.
285 75 16, 295 75 16 or 33x12.50 are the popular or most available reasonable sizes in that range. All will be fine on a 10” wide rim.
 

chevy79_qa

Junior Member
Joined
Oct 2, 2022
Posts
23
Reaction score
17
Location
qatar
First Name
fidal
Truck Year
1979
Truck Model
k20
Engine Size
460 BBC
Like I said above, I wouldn’t go more than a nominal 33” tire.
285 75 16, 295 75 16 or 33x12.50 are the popular or most available reasonable sizes in that range. All will be fine on a 10” wide rim.
Thanks buddy helped me a lot much love from the Middle East.
 

chevy79_qa

Junior Member
Joined
Oct 2, 2022
Posts
23
Reaction score
17
Location
qatar
First Name
fidal
Truck Year
1979
Truck Model
k20
Engine Size
460 BBC
How about some more about that truck?
How’s one come across a truck like that in Qatar?
People mostly buy the step side and they were sold in qatar around the early 80’s only a few long beds were sold during those years. Mine was from the US I don’t know from which state though exactly but it was beat to hell. I had a full rotisserie restoration body and frame done on it. It’s got a 454/builtTh400/np241 (hypereutectic pistons, aluminum heads, intake, big cam and got it converted to an efi from Holley) didn’t put it on the dyno yet because i’m working on my other projects. I don’t how you guessed I’m from qatar but great guess :)
 
Last edited:

Forum statistics

Threads
44,162
Posts
950,642
Members
36,275
Latest member
2manysquares2care
Top