For those running 18x12...
Thread Starter
Drifting
Joined: Oct 2002
Posts: 1,710
Likes: 0
From: Langhorne PA
For those running 18x12...
The next winter project is to mini tub my vert and put 345's on the rear. Called Fikse and for about $500, they can widen my existing rims, which are 18x10.5 currently. After talking with LPE, (was going with their Minitub Kit) they say there would be some rubbing on the upper A-arm when lifting, and rubbing on the lower A-arm under compression of the shocks in bouncy road conditions. When I looked (the car is currently on jacks for some winter projects 
), there wasn't the extra 1-1/2" between the upper A-arm and rim.
Does this happen to you? I was thinking that if the rim and upper A-arm contact when the car is lifted, how do you get the wheel off? What have you done? Any suggestions??? I know that SOMEONE here has the same problem.
Thanks,
Dan
BTW The easiest way seems to be to switch to 19x12's and sell the current set. It's tax time and for $$$ reasons, will not cross that bridge...
), there wasn't the extra 1-1/2" between the upper A-arm and rim. Does this happen to you? I was thinking that if the rim and upper A-arm contact when the car is lifted, how do you get the wheel off? What have you done? Any suggestions??? I know that SOMEONE here has the same problem.
Thanks,
Dan
BTW The easiest way seems to be to switch to 19x12's and sell the current set. It's tax time and for $$$ reasons, will not cross that bridge...
Team Owner
Joined: Mar 2003
Posts: 96,496
Likes: 82
St. Jude Donor '03 through '17
I've done way too much research on this topic. Your best bet is to go with 19x12 as it will travel past all the spots it will rub. HRE, CCW and Ed @ LPE all confirmed this to me. I was going to have HRE widden my 18's as well but I don't want to rub anything. With all my new power comming into play and having the mini tub done as well it looks like I'll have to get rid of my current rims and go to 19x12's. 
Le Mans Master
Joined: Sep 2004
Posts: 7,027
Likes: 6
From: Shiloh Ohio
Originally Posted by jersey jay
I've done way too much research on this topic. Your best bet is to go with 19x12 as it will travel past all the spots it will rub. HRE, CCW and Ed @ LPE all confirmed this to me. I was going to have HRE widden my 18's as well but I don't want to rub anything. With all my new power comming into play and having the mini tub done as well it looks like I'll have to get rid of my current rims and go to 19x12's.
Race Director
Joined: Aug 1999
Posts: 16,935
Likes: 26
From: Lackey, my own dragstrip VA.
Virginia Events Coordinator
Cruise-In IV Veteran
Cruise-In V Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
NCM Ambassador
Originally Posted by Dr. Dan
The next winter project is to mini tub my vert and put 345's on the rear. Called Fikse and for about $500, they can widen my existing rims, which are 18x10.5 currently. After talking with LPE, (was going with their Minitub Kit) they say there would be some rubbing on the upper A-arm when lifting, and rubbing on the lower A-arm under compression of the shocks in bouncy road conditions. When I looked (the car is currently on jacks for some winter projects ), there wasn't the extra 1-1/2" between the upper A-arm and rim.
Does this happen to you? I was thinking that if the rim and upper A-arm contact when the car is lifted, how do you get the wheel off? What have you done? Any suggestions??? I know that SOMEONE here has the same problem.Thanks,DanBTW The easiest way seems to be to switch to 19x12's and sell the current set. It's tax time and for $$$ reasons, will not cross that bridge...
), there wasn't the extra 1-1/2" between the upper A-arm and rim. Does this happen to you? I was thinking that if the rim and upper A-arm contact when the car is lifted, how do you get the wheel off? What have you done? Any suggestions??? I know that SOMEONE here has the same problem.Thanks,DanBTW The easiest way seems to be to switch to 19x12's and sell the current set. It's tax time and for $$$ reasons, will not cross that bridge...
Here is a pic of how lowered it is
More info in my photos
Thread Starter
Drifting
Joined: Oct 2002
Posts: 1,710
Likes: 0
From: Langhorne PA
AT&NB
First of all, really like the look and view that you show. I thought that a +74 would set the wheel too far outboard, causing a rub on the fender lip. Was told something more like a +78 (I know...4mm, big deal) would be correct. Which part of the inner fender plastic...in or out? Saw a post where someone wore through the inner plastic.
Also, I'm lowered only on stock bolts, thread and a half showing, fwiw.
First of all, really like the look and view that you show. I thought that a +74 would set the wheel too far outboard, causing a rub on the fender lip. Was told something more like a +78 (I know...4mm, big deal) would be correct. Which part of the inner fender plastic...in or out? Saw a post where someone wore through the inner plastic.
Also, I'm lowered only on stock bolts, thread and a half showing, fwiw.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
Originally Posted by Dr. Dan
AT&NB
First of all, really like the look and view that you show. I thought that a +74 would set the wheel too far outboard, causing a rub on the fender lip. Was told something more like a +78 (I know...4mm, big deal) would be correct. Which part of the inner fender plastic...in or out? Saw a post where someone wore through the inner plastic. Also, I'm lowered only on stock bolts, thread and a half showing, fwiw.
First of all, really like the look and view that you show. I thought that a +74 would set the wheel too far outboard, causing a rub on the fender lip. Was told something more like a +78 (I know...4mm, big deal) would be correct. Which part of the inner fender plastic...in or out? Saw a post where someone wore through the inner plastic.
Also, I'm lowered only on stock bolts, thread and a half showing, fwiw.My wheels fit perfectly flush with the fender. They measure 3.5" from the hub to the outer lip.
A 74mm offset on a 12" wheel would give 3.6" from the hub to outer lip.
78mm would be 3.5" like mine.
Remember too, just alignment (camber) settings can pivot the top of the tire in or out considerably too. Adding camber will tuck the top of the tires in, and could add to inner clearance issues.
That 1/8" difference is pretty insignificant when comparing the wheel lip to the fender edge, but could be susbtantial on the inside.
I think 74mm would be the 'safer" offset to use if clearances are this tight.
Race Director
Joined: Aug 1999
Posts: 16,935
Likes: 26
From: Lackey, my own dragstrip VA.
Virginia Events Coordinator
Cruise-In IV Veteran
Cruise-In V Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
NCM Ambassador
Originally Posted by Dr. Dan
AT&NB
First of all, really like the look and view that you show. I thought that a +74 would set the wheel too far outboard, causing a rub on the fender lip. Was told something more like a +78 (I know...4mm, big deal) would be correct. Which part of the inner fender plastic...in or out? Saw a post where someone wore through the inner plastic. Also, I'm lowered only on stock bolts, thread and a half showing, fwiw.
First of all, really like the look and view that you show. I thought that a +74 would set the wheel too far outboard, causing a rub on the fender lip. Was told something more like a +78 (I know...4mm, big deal) would be correct. Which part of the inner fender plastic...in or out? Saw a post where someone wore through the inner plastic.
Also, I'm lowered only on stock bolts, thread and a half showing, fwiw.Here are a few pictures that show the rubbing, same on both sides.Very minor and mainly with 2 people loaded for a trip with the 27.5" dia tires. It only hits plastic and rubber so I am not concerned. Over 5k miles with auto xing, drag racing, long trips w/o issue.
As you can see I have trimmed away some of the stock liner.
I used rubber to fill in the gap from tubbing vs fiberglass.......my rear fenderwells will be full of rubber any way
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Drifting
Joined: Oct 2002
Posts: 1,710
Likes: 0
From: Langhorne PA
Originally Posted by ALLTHROTTLE&NOBOTTLE
We are lowered the same amount.
Here are a few pictures that show the rubbing, same on both sides.Very minor and mainly with 2 people loaded for a trip with the 27.5" dia tires.
Here are a few pictures that show the rubbing, same on both sides.Very minor and mainly with 2 people loaded for a trip with the 27.5" dia tires.
Y2Kvert4me,
Are you running 18's in the rear??? Your wheels really fill that wheelwell! If they are 19's, LPE tells me that all problems resolve themselves.
Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
Originally Posted by Dr. Dan
Y2Kvert4me,
Are you running 18's in the rear??? Your wheels really fill that wheelwell! If they are 19's, LPE tells me that all problems resolve themselves.
Are you running 18's in the rear??? Your wheels really fill that wheelwell! If they are 19's, LPE tells me that all problems resolve themselves.
My comments were posted strictly for your offset calculation purposes, and to illustrate what that 4mm difference means as far as fitment...not to compare what's on my car, other than how far they extend out to the outside fender edge.
The only point of me mentioning my wheels was that they fit perfectly flush with the outer fender lip. That's only a reflection of the hub-to-fender distance, whcih doesn't change unless you have wider fenders. Whether you're tubbed for additional inner clearance makes no differemce...the hub-to-fender lip distance remains at 3.5". That's ideally what you'd want to shoot for, but in the case of AT&NB's car, he's at 3.6" to gain that little bit of inner clearance, since it is obviously so tight with the 18" dia.
Hope that clarifies.
Last edited by Y2Kvert4me; Feb 28, 2005 at 08:30 PM.
Race Director
Joined: Aug 1999
Posts: 16,935
Likes: 26
From: Lackey, my own dragstrip VA.
Virginia Events Coordinator
Cruise-In IV Veteran
Cruise-In V Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
NCM Ambassador
Originally Posted by Dr. Dan
27.5"??? I saw on 1010tires.com site that 345/30/18's have a diameter of 26.14, almost identical to my 295/35/18's. Was told that I needed to keep the dia. the same or else problems occur. That size difference may be enough (11/16" on the radius) to clear the wheelhouse...No?
One is the 345/30/18drs
& the other is 345/35/18s I use for trips:
As long as the front to rear rake is at least 4% (Smaller dia tire up front) you should be ok. Matter a fact, I ran 275/40/18 OEM MAG tires and rims on all 4 corners for days to see if I liked the 18" all around look and had no traction/active handeling issues
Each car/tire combo will act different, good luck.
Thread Starter
Drifting
Joined: Oct 2002
Posts: 1,710
Likes: 0
From: Langhorne PA
Originally Posted by ALLTHROTTLE&NOBOTTLE
I have 2 sets of rear rims/tires.
One is the 345/30/18drs & the other is 345/35/18s I use for trips:
Each car/tire combo will act different, good luck.
One is the 345/30/18drs & the other is 345/35/18s I use for trips:
Each car/tire combo will act different, good luck.
Y2Kvert4me,
The only point of me mentioning my wheels was that they fit perfectly flush with the outer fender lip. That's only a reflection of the hub-to-fender distance, whcih doesn't change unless you have wider fenders. Whether you're tubbed for additional inner clearance makes no differemce...the hub-to-fender lip distance remains at 3.5". That's ideally what you'd want to shoot for, but in the case of AT&NB's car, he's at 3.6" to gain that little bit of inner clearance, since it is obviously so tight with the 18" dia.
Hope that clarifies.
Hope that clarifies.
Race Director
Joined: Nov 2001
Posts: 18,682
Likes: 4
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
One more thing that you will encounter on a lowered car is the outer edges of leafsprings rubbing against the inner bead of the wheels. It has nothing to do with tubbing and if you have a Z51 suspension and your car is lowered, your leafspring will brush against the very outer edges of your wheel inner barrel.
Race Director
Joined: Aug 1999
Posts: 16,935
Likes: 26
From: Lackey, my own dragstrip VA.
Virginia Events Coordinator
Cruise-In IV Veteran
Cruise-In V Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
NCM Ambassador
Originally Posted by Dr. Dan
The point that I'm questioning is that one set had rubbed your inner liner. I was wondering if the 35 series was to blame because it would have a larger radius, getting it almost 3/4" closer to the wheelhouse as measured from the center of the axle. That would be enough for clearance (the 30 series, I mean), wouldn't it?
