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S550 front wheel fitment questions.

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All,

First post so forgive me if I simply just didnt do enough digging to find my answer to this. I am currently running 19x10's in the front and 19x11 in the rear with 275 and 305s respectively. I'm getting new wheels (18's) and new rubber and wanted to try a 305 all around square set up. I've heard different theories on how this can be done, some cheap, some pricey, some hard on tires, etc. I wanted to ask to anyone who runs this set up what they did to accomodate the 305's up front. So far I've seen a 25mm wheel spacer and ARP studs is a popular move. I wanted to know if anyone has had issues on the track when going that route. Having the wheel further away from center naturally makes me nervous just because of the added physical stress on the hub. Also, can a larger wheel offset counteract the need for the 25mm spacer?

I appreciate any help.

Murray
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Spacers actually reduce the effective offset, so you'd be looking for a smaller +offset number. But that'll put you in the situation where you have two wheels in each of two different offsets.

IIRC, 25mm spacers are used with 18x11 wheels whose +offsets are something like +52 in order to come up with an effective offset of around +27. +52 was chosen because it works on the rear axle without any spacers at all, so you get to keep any four wheel tire rotation scheme.


Norm
 
Spacers actually reduce the effective offset, so you'd be looking for a smaller +offset number. But that'll put you in the situation where you have two wheels in each of two different offsets.

IIRC, 25mm spacers are used with 18x11 wheels whose +offsets are something like +52 in order to come up with an effective offset of around +27. +52 was chosen because it works on the rear axle without any spacers at all, so you get to keep any four wheel tire rotation scheme.


Norm
Thanks for the help! Any reccomendations on spacer, stud, and wheel brands?
 
466
438
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Thanks for the help! Any reccomendations on spacer, stud, and wheel brands?
Apex (https://www.apexraceparts.com) is a popular choice for quality 18x11 wheels and if you look on their site they also have a fitment guide. They specialize in track wheels. I believe they have a group buy coming up in a few weeks so you can save some dollars. Also they have track warranty where they allow you to replace damaged wheels from track use for half off.

For spacers, I bought a set from Motorsport Tech (https://www.motorsport-tech.com). They are a bit pricey but they are worth it and they can make it in black if you go with black wheels. Slip on spacers is what you want.

Hope that helps
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Thanks for the help! Any reccomendations on spacer, stud, and wheel brands?
Either Apex or Forgestar for the wheels. The Apex wheels seem to be normally made available in a single offset (made to fit the rear without a spacer), with spacers then required for the front. Forgestars - those available through Vorshlag anyway, come in specific front and specific rear offsets at least in the 11" wide category and don't need any spacers at all. In terms of wheel track width and how front track compares to rear track, or in "wheel rates", there's no difference between the two approaches.

ARP for the wheel studs. But it's probably better to get the Ford Racing M-1104 hubs if they're available, which come with the longer ARP studs already fitted. There's more than one part number, which differ in the suffix letter (B or AB, at least).

I don't have any particular preference in spacers, as I'll only use the thinnest spacer necessary to solve a strut side rub. I've even fabbed my own from sheet aluminum, when less than 1mm was all the spacing I needed.


Norm
 
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Ludachris

Chris
Staff member
Moderator
1,658
1,962
Exp. Type
HPDE
Exp. Level
5-10 Years
Newcastle, CA
Apex (https://www.apexraceparts.com) is a popular choice for quality 18x11 wheels and if you look on their site they also have a fitment guide. They specialize in track wheels. I believe they have a group buy coming up in a few weeks so you can save some dollars. Also they have track warranty where they allow you to replace damaged wheels from track use for half off.

For spacers, I bought a set from Motorsport Tech (https://www.motorsport-tech.com). They are a bit pricey but they are worth it and they can make it in black if you go with black wheels. Slip on spacers is what you want.

Hope that helps
Apex also has a good guide on sizing/figment posted on their site. I might ask them if we can post it here on the site as an FAQ article.
 
1,040
1,088
Monaca Pa
I have never had a problem with spacers. I run Apex 19x11 with 305-30 Nittos square. I also have Eibach sport line springs which maybe to low. With out camber plates Tire just touched on left front at the track. Put camber plates with 3 degrees negative camber and now it clears. I might get new springs that sit a little higher.BAFC4C5B-C27C-442F-9267-54D3231BCC94.jpeg031212C3-35C4-42D6-9545-C500CD653DBB.jpeg8D1790EC-17F7-4BAB-9FA7-39AEC51A1031.jpeg
 
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TymeSlayer

Tramps like us, Baby we were born to run...
3,787
2,740
Exp. Type
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3-5 Years
Brighton, Colorado
Glad you it didn't cause you an issue while running on the track. I could only get -2.7 degree camber with my set-up with T-springs, 19x11 305-30-19 RE7R's 25MM spacers and the MM caster Camber plates. No problems so far although I did run into the passenger side rubbing a bit on the a-arms but think that was more a result of spinning at PPIR last year because I haven't seen that issue since.
 
1,246
1,243
In the V6L
When it comes to spacers and racing, this AJ Hartman video has an interesting moment between 20:50 and 21:00 minutes:

The spacers you see are the ones with adapter-style lugs. The spacer has its own set of lugs and and is bolted to the hub with the factory lugs and nuts.

Conventional wisdom is "don't use spacers at all if you can avoid it, but if you must, just don't use spacers like that". Doesn't seem to cause any problems for AJ.
 

boardkat

CAMtard
131
179
Exp. Type
W2W Racing
Exp. Level
10-20 Years
Lake Oswego, OR
JAJ said:
Conventional wisdom is "don't use spacers at all if you can avoid it, but if you must, just don't use spacers like that". Doesn't seem to cause any problems for AJ.
That isn't the conventional wisdom I've been privy to! All advice I've received is that past 1", an adapter is the only way to go, to reduce load on the studs (and the desire to keep stud length reasonable). FWIW, I've been driving my car hard for 5 seasons on 30, 35 and 38mm adapters at various points up front without issue.
 

Apex Wheels

Race Proven, Street Approved
Supporting Vendor
670
1,061
Exp. Type
Time Attack
Exp. Level
5-10 Years
Bay Area, CA
18x11" ET52 is our best selling Mustang wheel for very good reasons. It supports pretty much every popular track tire for the Mustang, is lightweight yet still durable, backed by a killer damaged replacement program, and can be rotated to extend tire life. Most suspension setups will need a 25mm spacer and extended wheel studs up front, while the rear is a direct fit. We recommend at least -2.5* of camber up front achieved via plates and NOT camber bolts as bolts eat up valuable inner clearance.

You can view our S550 fitment guide here: https://support.apexraceparts.com/h...5483093-S550-Mustang-Wheel-Tire-Fitment-Guide and @Ludachris feel free to use these however you'd like! We have an S197 guide as well

The right spacers on track is absolutely a non-issue, even with the stickiest of tires. We have hundreds (probably thousands by now) of customers on this forum running/abusing our wheels. Make sure the spacers are hub-centric and from a reputable company and you won't have any problems. We recommend OP Mustang for spacers as our Mustang spacers will not be available until later this year.

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- Cory
 

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