17" Wheel backspace question...
Thread Starter
Drifting
Joined: Sep 2001
Posts: 1,427
Likes: 1
From: Boxford Mass
17" Wheel backspace question...
Sorry, I know this topic has been covered numerous times but the "search feature" on our new and improved forum doesn't seem to find anything. Could be operator error too.
Anyway, what I'd like to know is the max backspacing for a 17" rim on my 71 with stock suspension. The reason I added the year is there appears to some differences between 80 c3s -vs- the earlier models.
I'm looking for the max wheel sizes for the front and rear without mods. I would also be interested in what some people fit with mods (offset t-arms, etc..)
Anyway, what I'd like to know is the max backspacing for a 17" rim on my 71 with stock suspension. The reason I added the year is there appears to some differences between 80 c3s -vs- the earlier models.
I'm looking for the max wheel sizes for the front and rear without mods. I would also be interested in what some people fit with mods (offset t-arms, etc..)
Pro
Joined: Sep 2004
Posts: 545
Likes: 8
From: Murphy Texas
This is a e-mail response I recieved from a dealer about some Smoothies for my '71
The 18x8 and 18x9 are the best fit for the wider rear if you do not have or
plan to install the offset rear trailing arms, otherwise, the 9.5" Smoothie
and 10" Smoothie II will protrude from the wheelwells out back.
The maximum backspace you can use without the aftermarket trailing arms is a
4.5" backspace. The factory 7" wheels had a 3.75" backspace and the factory
8" wheels had a 4" backspace.
In order to get a 4" backspace, you will need to choose the traditional
Smoothie in 17x8 and 17x9.5 with 4" front and 4.5" rear backspace or 17x8
front and rear with 4" backspace.
We can also build the Smoothie II but I would have to recommend the 17x8
front and rear or 18x8 front and 18x9 rear, the 17x10 just does not fit
right without the offset trailing arms. The problem with the Smoothie II is
the minimum backspace is 4.5" which tucks the wheel/tire well into the
wheelwells.
If you want 17" and you want a wider rear, the traditional stepped lip
Smoothie is the way to go in 17x8 and 17x9.5 with 4" front and 4.5" rear
backspace.
The 18x8 and 18x9 are the best fit for the wider rear if you do not have or
plan to install the offset rear trailing arms, otherwise, the 9.5" Smoothie
and 10" Smoothie II will protrude from the wheelwells out back.
The maximum backspace you can use without the aftermarket trailing arms is a
4.5" backspace. The factory 7" wheels had a 3.75" backspace and the factory
8" wheels had a 4" backspace.
In order to get a 4" backspace, you will need to choose the traditional
Smoothie in 17x8 and 17x9.5 with 4" front and 4.5" rear backspace or 17x8
front and rear with 4" backspace.
We can also build the Smoothie II but I would have to recommend the 17x8
front and rear or 18x8 front and 18x9 rear, the 17x10 just does not fit
right without the offset trailing arms. The problem with the Smoothie II is
the minimum backspace is 4.5" which tucks the wheel/tire well into the
wheelwells.
If you want 17" and you want a wider rear, the traditional stepped lip
Smoothie is the way to go in 17x8 and 17x9.5 with 4" front and 4.5" rear
backspace.
Safety Car
Joined: Jan 2001
Posts: 3,637
Likes: 27
From: Norwalk Ct
"If you want 17" and you want a wider rear, the traditional stepped lip
Smoothie is the way to go in 17x8 and 17x9.5 with 4" front and 4.5" rear backspace."
Not sure I agree with that (to what the dealer said..not the forum member)
If you try and put a 17 x 9.5 on the back with only 4.5" backspace, that means the wheel will stick out another inch than stock. From my mearsurements that will have the outer lip of the wheel outside the wheel arch, which doesn't look nice in my opinion, so fender flares woudl ne necessary and you run the risk of hitting the wheel arch with the tire on suspension travel if you dont.
I am running a 17 x 9.5 with 5.5" backspacing on the rear of mine, with a 285/40 tire and offset trailing arms ...it is close.....but it seems to fit ok.
I would recommend sticking with 17 x 8 all round if you are goign to stay with stock T/A's and no fender flares........but with a offset TA you can add up to 2" off backspacing on a wheel (and leave 4" dish).
cheers,
Nick
Smoothie is the way to go in 17x8 and 17x9.5 with 4" front and 4.5" rear backspace."
Not sure I agree with that (to what the dealer said..not the forum member)
If you try and put a 17 x 9.5 on the back with only 4.5" backspace, that means the wheel will stick out another inch than stock. From my mearsurements that will have the outer lip of the wheel outside the wheel arch, which doesn't look nice in my opinion, so fender flares woudl ne necessary and you run the risk of hitting the wheel arch with the tire on suspension travel if you dont.
I am running a 17 x 9.5 with 5.5" backspacing on the rear of mine, with a 285/40 tire and offset trailing arms ...it is close.....but it seems to fit ok.
I would recommend sticking with 17 x 8 all round if you are goign to stay with stock T/A's and no fender flares........but with a offset TA you can add up to 2" off backspacing on a wheel (and leave 4" dish).
cheers,
Nick
