Radiused fenders... only for the crazies

[One Ton VIP]

Radiusing a fender is basically a general term used to describe cutting the fender opening, usually enlarging the diameter in order to accomodate and "frame" larger wheels. Hot rod guys do it all the time cuz a lot of them are running crazy size wheels/tires, esp in the backs, and also cuz it's the only way to ensure their fender openings end up looking the same side-to-side, since a lot of those cars aren't perfectly-constructed from the factory to begin with, and a lot have had replacement fenders used that weren't always an exact duplicate of the original. Anyway, this is something I foresee we will be seeing a lot more of from the big dog cars from Japan. It's one thing to radius a hot rod fender (or the fender of any full frame car or truck) since there's rarely an attached inner fender to contend with, and the body panels are usually not structural in a full frame vehicle, so you can cut away to your heart's content w/o worrying too much about compromising the integrity of your chassis. But when you start radiusing the fenders of a unibody car... now you're playing with power. AND when you have a rear door to deal with... more props to you when you can work that all out. Here's some examples of radiused fenders:

Accord: notice how the top edge of the champagne car's front fenderwell is like in line with the door handles:
http://i6.tinypic.com/153abuw.jpg
vs. stock which has the top edge of the front fender is more in line with the bottom of the door handles:
http://www.warehousemotors.com/item_images/755-142-3678.jpg

and this car... just check out how much the rear fender invades into the rear edge of the door! pretty awesome job recontouring the door though:
http://www.flexnet.co.jp/autogallery2006/04/image1299.JPG

unknown car: I have no idea what kinda car this is... I want to say a crown, but I'm sure I'm way off. Look at how beautifully that rear fenderwell FRAMES that huge weds kranze ratzinger wheel!
http://carview.r3h.net/images3.carview.co.jp/carlife/images/UserCarPhoto/268403/p2.jpg

Q45: I'm embarassed cuz my car is nowhere near as nice as the above... but I did this photoshop of an old pic of my car to illustrate, side-by-side, how radiusing the fenders can create a dramatically diff look
http://www.onetongarage.com/misc/qfendermods.jpg

Ultimately I think sliggity slamming a stock fendered car over big wheels will give you that "slammed" look... but sliggity slamming a car with radiused fenders over big wheels may not make it appear as low upon casual glance, but then you realize that the wheels look like they actually fit the car (and you can still run them flush to the fenders, not sunken), and the car body itself looks sleeker, lower, wider, meaner (cuz you've effectively reduced the fender height), and like the car was actually MADE to ride that low.. (think exotic sports car). I wonder when we'll start seeing such madness in the US...

[EndlessNA1]

This is actually a VERY easy thing to do IF you know what you are doing and have the right people helping you. Its just a matter if you can get the suspension that low so get that effect because most cars will bottom out the control arms before if even gets near the height desired.

Check out my NSX:
The front fender have been rolled/pulled and radiused to fit the uber wide and low offset (for NSX) wheel.
http://img.photobucket.com/albums/v731/SugoiTanuki/sig.jpg

IMHO I really dont think would good on a vip styled car.

[nezumimaru]

great write up...
I am always impressed by how some people take aesthetics of thier cars so seriously
always looking for the next thing to maximize the visual effect beyond lowering their cars
and taking wheel fitment to a whole different level

this seems to be the new frontier of wheel fitment?

[Dominik]

Actually, it can and does look awesome on a vip car. This green car is in one of the recent magazines and the fenders are raised an amazing amount. the rear door has been completely reshaped to acomodate the new wheel arch. Trying to find better pics of it though
http://www.k-break.com/event/35gw/01.jpg

Its also popular on cars that want to go for 20"s or 21s on the rear with 19s on the front.

this is actually not all that new because I have been noticing alot of the vipcars in the mags for the last year or 2 at least, having rear fenders listed as "kiriage" or "cut and raised"
Usually, the rear is raised to match the line of the front of the car since on most cars the rear fender is much lower than the front

[stankubrick]

I love that champagne accord...http://img.photobucket.com/albums/v18/stankubrick/graemlins/lvl.gif

What do they do to keep the structural integrity of the chassis? or is this why radiused fenders are only for the crazies :)

[ceso@fd]

you mean like this..sorrie spanky if im using your pics but just for an example :) http://www.driftunit.com/hellaflush/wp-content/uploads/2006/10/AFb.jpg

[EndlessNA1]

Actually, it can and does look awesome on a vip car.


I dunno. To me, it seems a little more dub style to use a wheel bigger than 20". Its like putting 19" rims on a honda civic.

[jzz30tt]

I dunno. To me, it seems a little more dub style to use a wheel bigger than 20". Its like putting 19" rims on a honda civic.


I think you're missing the point. The point is that your making such a large wheels look awesome, instead of a jacked up piece of shit like most "dub" rides tend to look like.

[elpresidente]

Current trend you are far behind. 21" becoming popular with 20" becoming normal. 19" is every day, but becoming less.

[One Ton VIP]

I think a lot of folks are still confused as to what exactly radiusing involves... it isn't a matter of just rolling, or even pulling a fender to the point where its shape is altered.. it's about literally cutting a new semi-circular shape out of the fender. This is easy on front fenders where you only have to deal with a single layer of fender skin. But the rear fenders of unibody cars (and even lots of post-50s full frame cars) are comprised of both an outer and inner fender that are bonded together, and depending on how much you want to lower the car, and how much you want to radius up the fender, you may find that you'll also have to do a bit of tubbing (which is when you cut/enlarge the inner fender). Here's another diagram I made illustrating the differences in the type of fender processing pertaining to this discussion:
http://www.onetongarage.com/misc/fenderprofile.gif

Now you'll see why radiusing a rear fender isn't as easy as people may think... and even more so when you've got a rear door that is in the way of your new fender opening.

presidente: I'm curious to see pics of these vip styled cars that are all running 21s... especially so considering that not many wheel manufacturers in Japan offer 21s, but most skip straight to 22s from 20s, as has been the industry norm dictated by the tire manufacturers. In fact, I'd even like to see pics of all the VIP styled cars running 20s that you also consider are behind the times. We'll probably have to refer to Japan for those also, as 95% of "VIP" folks in the US are still relegated to buying japan's junky, clapped out 18s and 19s for their VIP cars

[chmercer]

the green GS and the accord wagon, how do they even drive that way? i know on my 240 that there is a big metal rail thing above the tire that makes it pretty hard to tuck the whole sidewall, there would be no way to cover the whole sidewall if the fender lip was raised any more.

looks like on thoes 2 cars the tire is like maybe and inch or 2 away from the underside of the fender sheet metal!!

[elpresidente]

I said 20" is more normal now (where 19" was normal before) and becoming more popular with 21" also used. Several wheel manufacturer have been making 21" wheel for some time such as Lowenhart, Lorinser, and Trafficstar. But other company like Brabus & DAD are also now making them. Although 21" wheels is more typical on larger sedan and European VIP car. I like 20" on many VIP cars and think with the right fitment it looks great. 19" is still good for smaller sedan, but with time things change. It is true that many company skip 21", but only because tire availability is small and expensive.

[mdenoga]

Now you'll see why radiusing a rear fender isn't as easy as people may think... and even more so when you've got a rear door that is in the way of your new fender opening.


yeah just like the previa's rear sliding door right? van u have too much time on your hands to make these digital illustrations haha :P great write up though.

[Dominik]

20"s are becoming common, but i have only ever seen 21"s on the rear of cars - with the radiused fenders as OneTon described

But on wider cars and especially older cars like Y32, UCF10, 130/140 Crowns and even G50 Q45/Pres', 19" is still the most popular size.

But the Garage Magical Y32 (My fav Jap built car) runs 18s, hence why i ran them on my car. Even then they run radiused fenders on the rear to get the chassis down low enough

[EndlessNA1]

I think you're missing the point. The point is that your making such a large wheels look awesome, instead of a jacked up piece of s*** like most "dub" rides tend to look like.


I'm not missing anything. I just dont like big wheels. I like wide low offset wheels that look proportioned to the car. Kinda reminds me of the import racer models http://us.st11.yimg.com/us.st.yimg.com/I/streetbeatcustoms_1917_177034226

But thats just my opinion about it. to each his own.

[AME_VIP]

this is a a whole 'nother level. Thanks for the great write up

[TrueslideXL]

There is nothing special about radiusing a fender on modern cars as it is not a load bearing structure, it's been done millions of times on pre crumple zone cars before and they have alot more metal to contend with. I can see where you are getting at as to how much more difficult it is for someone who only has ever worked on older cars to adapt to much more modern ones, but companies like Unique and Chip Foose D. who have sold thousands of new cars under their collaborations will differ. This is an advanced project better left to professionals, and if someone sees a difference between working on a new or old model, they don't have what it takes to perform the work. The recent "trend" is just another example of so called "tuners" pretending to be on the new frontier. Been there, done that, it still the same old look with a new great taste. It's nothing special. Those old guys really knew how to work metal. There's still so much that younger guys need to learn before that generation dies out.

[pitchedup]

great write-up, did not know that this was taken part in the vipstyle scene.

[trbobrk]

Great Thread!

They have been doing this on touring cars for years. When you slam the car to the ground the only way to get the huge tires in the front to turn without scraping the fender is to remove that part of the fender. Rears can tuck behind the fender since they only go up and down.

[Bippu_Ten]

not bad ... good info I hope this thread stays alive

[One Ton VIP]

There is nothing special about radiusing a fender on modern cars as it is not a load bearing structure, it's been done millions of times on pre crumple zone cars before and they have alot more metal to contend with. I can see where you are getting at as to how much more difficult it is for someone who only has ever worked on older cars to adapt to much more modern ones, but companies like Unique and Chip Foose D. who have sold thousands of new cars under their collaborations will differ. This is an advanced project better left to professionals, and if someone sees a difference between working on a new or old model, they don't have what it takes to perform the work. The recent "trend" is just another example of so called "tuners" pretending to be on the new frontier. Been there, done that, it still the same old look with a new great taste. It's nothing special. Those old guys really knew how to work metal. There's still so much that younger guys need to learn before that generation dies out.


Quite the contrary, most every sheet metal component on a unibody car is load-bearing nowadays... even more so within the last few years as companies cut costs by making construction simpler by spending more $$ on extensive finite analyses to try and reduce the number of body parts, by making each one perform a greater function. With that said, it still IS a big deal to radius the rears of a unibody car. And yes, peeps like Chip Foose and other long-time hot rod builders have all done it, but I sorta doubt places like Unique have... West Coast Customs I believe has on a few of their really high-profile show cars... but that's cuz their fabrication abilities are far better than what we see on mtv.
Oh, and there's a MARKED difference between radiusing and tubbing a new unibody car, vs. a much older full-frame car, especially if you really do care to ensure structural integrity is maintained...of course, people who care to look at and scrutinize both will realize that though. But after all is said and done, the point here as it pertains to VIP cars is that we will probably be seeing a lot more VIP cars and wagons from Japan getting majorly modified fenders (front and rear) within the next 1-2 years... AND that it's hard enough on the rear of a unibody car, but even more so on a car with 4 doors. Oh, and I should add, "AND it's hard to make it look good and not like ass"... cuz anyone can hack shit up and make it look like ass, but it's gonna take some skill to make things look like they belong.

[One Ton VIP]

I'm not missing anything. I just dont like big wheels. I like wide low offset wheels that look proportioned to the car. Kinda reminds me of the import racer models http://us.st11.yimg.com/us.st.yimg.com/I/streetbeatcustoms_1917_177034226

But thats just my opinion about it. to each his own.


Ah.. that's just it though... if done right the car does NOT look like that toy.. the wheels would still be flush, AND big. That's the ultimate point: you get a car that is physically super low to the ground, with wheels that are big, and flush (not sunken like that) and look like they belong on the car. And your car ends up having much smaller fender height front and rear, which also gives the effect of a longer, wider, lower, sleeker, meaner body. I mean there really is no downside to this if done correctly... but I think the reason we haven't seen more cars like this is cuz it's not as easy as some people here are making it out to be. That, and a lot of people still are a little confused about what exactly it entails.

[TrueslideXL]

Quite the contrary, most every sheet metal component on a unibody car is load-bearing nowadays... even more so within the last few years as companies cut costs by making construction simpler by spending more $$ on extensive finite analyses to try and reduce the number of body parts, by making each one perform a greater function.

With that said, it still IS a big deal to radius the rears of a unibody car.

And yes, peeps like Chip Foose and other long-time hot rod builders have all done it, but I sorta doubt places like Unique have... West Coast Customs I believe has on a few of their really high-profile show cars... but that's cuz their fabrication abilities are far better than what we see on mtv.


Unique is an original shop whose name was copied by the Unique you know on MTV, they are one of the country's premier shops.

And fenders are not load bearing on a unibody car unless they are bolted on to the unibody as a seperate piece which is how the FRONT end of a majority of cars are made so that they can absorb front impacts better. Today most American and Japanese cars are made this way.

[One Ton VIP]

Ah you are referring to the Unique that produces short runs of high-end production classics and the like... yes, they are definitely nothing like the Unique on that one show on Speed Channel actually. I've watched that other Unique show like twice and it hurt my head. Also, modern day cars are so "well-engineered" that even the windshield and backlite are designed to be load-bearing...look into that. And front fenders are actually not load-bearing units...parts designed to absorb impacts are actually not called load-bearing. A part that is load-bearing is designed to sustain strain, and thus, load, from other components attached to it. For example, a load bearing beam in a house is meant to support, via transfer of force, a series of rafters through a post, to the foundation, for example. Rear fender quarters, though not seemingly very structural by nature, are, in most modern cars, part of a "triangulated" unit that transfers loads between the parts where it is firmly-attached (i.e. welded): door jamb to c-pillar to trunk well to rear trunk wall to inner fender to rocker panel. But any argument is futile because the point is still that to adequately-, and correctly-modify a rear unibody fender in this fashion requires quite a bit of work. I'm not even sure why anyone is trying to argue with that?!? Unless someone wants to post a how-to that shows how easy it is, cuz I'd love to see that, too.

[Dominik]

Good timing for this topic. The current issue of VIPSTYLE magazine (December) has an article on "arch kiriage" or radiused fenders. Unfortunately its mainly concerned with the front fenders but it shows pics of a crazy low GS that has had the rears raised at the same time. I'm sure its nothing groundbreaking, but it does show how they do the fronts.... With any luck it will detail the rear fenders in the next issue (I havent read the article yet so i dont know if they mention the rears other than in photos).

Also, its obvious but it might be worth mentioning that when you raise the arches like this, it just means you have more fender gap when you raise the car up. For airbagged rides it would mean you are either going to be riding at 0psi or living with stock-looking fender gaps. All the ones i have seen in the mags run on coilovers, and i can only assume they ride low permanently

[JDMJim]

the champagne and yellow accord wagons are the same car in different states of build

[One Ton VIP]

Also, its obvious but it might be worth mentioning that when you raise the arches like this, it just means you have more fender gap when you raise the car up. For airbagged rides it would mean you are either going to be riding at 0psi or living with stock-looking fender gaps. All the ones i have seen in the mags run on coilovers, and i can only assume they ride low permanently


I think the trick is to set your ride height (usually with the lowest part of the car about 3.5-4" above ground), and then radius the fenders to tuck just a tad bit of tire tread... this way, if you do have air susp, when you air down at park, the wheel lip will just kiss the fender, or ever so slightly tuck in a couple mm...

[TrueslideXL]

I think the trick is to set your ride height (usually with the lowest part of the car about 3.5-4" above ground), and then radius the fenders to tuck just a tad bit of tire tread... this way, if you do have air susp, when you air down at park, the wheel lip will just kiss the fender, or ever so slightly tuck in a couple mm...
I agree, but many cars are already so low without the fenders cut that they require significant modification of things like the suspension pick up mounts which are already overstretched. I think that's where you start getting into the difference between most tuners and the top 5% who really know what they are doing. It takes alot to completely reengineer the suspension geometry like that. People look at some of these VIP cars and say; "oh I can do that" but it's those small mm differences you refer to that cost the big dollars.

[kyeguy82]

any more pictures of examples?

[Dominik]

If you can, try to get yourself a copy of the Feb 2007 issue of VIPStyle magazine. They have a 14 Majesta in there which takes the cake as far as i am concerned.

Some of the things i can make out from the pictures and captions:
* Front inner fenders modified, wiring looms rerouted
* Front and rear fender arches raised (radiused)... Several inches in the rear
* Floor-pans under the car cut and smoothed. Chassis rails appear to be removed and rewelded on the INSIDE of the cabin
* Urethane layer between smoothed floorplan and floorpan protector plate so that bottoming out doesnt do as much damage
* Front member raised (couldnt see whether they raised the engine), and a protector plate covers oil pan etc
* Rear cross-member raised, rear diff mounting point raised 5cm so that driveshaft stays level yet closer to the body (confirming my suspicion that the engine has been raised)
* Exhaust pipe routed in the extra space provided by raised driveshaft
* obviously full custom suspension parts, starting with one-off coilovers, all custom arms and customised knuckles to provide maximum clearance at low heights.
* The car uses SS-kits, which are meant for factory-air suspensioned cars to allow them to go lower than the factory struts will normally allow - by raising the hub-knuckle in relation to the suspension strut. I've never seen them used on coilover'ed cars, I suspect its to allow clearance somehow
* Rear exhaust work is pretty amazing.

Put simply, this car is pretty amazing. And its on coilovers too... No sissy airsuspension going on here!

[gmckey]

please scan pics the Dominik!

[carlos]

If you can, try to get yourself a copy of the Feb 2007 issue of VIPStyle magazine. They have a 14 Majesta in there which takes the cake as far as i am concerned.

Some of the things i can make out from the pictures and captions:
* Front inner fenders modified, wiring looms rerouted
* Front and rear fender arches raised (radiused)... Several inches in the rear
* Floor-pans under the car cut and smoothed. Chassis rails appear to be removed and rewelded on the INSIDE of the cabin
* Urethane layer between smoothed floorplan and floorpan protector plate so that bottoming out doesnt do as much damage
* Front member raised (couldnt see whether they raised the engine), and a protector plate covers oil pan etc
* Rear cross-member raised, rear diff mounting point raised 5cm so that driveshaft stays level yet closer to the body (confirming my suspicion that the engine has been raised)
* Exhaust pipe routed in the extra space provided by raised driveshaft
* obviously full custom suspension parts, starting with one-off coilovers, all custom arms and customised knuckles to provide maximum clearance at low heights.
* The car uses SS-kits, which are meant for factory-air suspensioned cars to allow them to go lower than the factory struts will normally allow - by raising the hub-knuckle in relation to the suspension strut. I've never seen them used on coilover'ed cars, I suspect its to allow clearance somehow
* Rear exhaust work is pretty amazing.

Put simply, this car is pretty amazing. And its on coilovers too... No sissy airsuspension going on here!

that thing sounds pretty fucking sweet. i would love to see pics.

[jstyle]

If you can, try to get yourself a copy of the Feb 2007 issue of VIPStyle magazine. They have a 14 Majesta in there which takes the cake as far as i am concerned.

Some of the things i can make out from the pictures and captions:
* Front inner fenders modified, wiring looms rerouted
* Front and rear fender arches raised (radiused)... Several inches in the rear
* Floor-pans under the car cut and smoothed. Chassis rails appear to be removed and rewelded on the INSIDE of the cabin
* Urethane layer between smoothed floorplan and floorpan protector plate so that bottoming out doesnt do as much damage
* Front member raised (couldnt see whether they raised the engine), and a protector plate covers oil pan etc
* Rear cross-member raised, rear diff mounting point raised 5cm so that driveshaft stays level yet closer to the body (confirming my suspicion that the engine has been raised)
* Exhaust pipe routed in the extra space provided by raised driveshaft
* obviously full custom suspension parts, starting with one-off coilovers, all custom arms and customised knuckles to provide maximum clearance at low heights.
* The car uses SS-kits, which are meant for factory-air suspensioned cars to allow them to go lower than the factory struts will normally allow - by raising the hub-knuckle in relation to the suspension strut. I've never seen them used on coilover'ed cars, I suspect its to allow clearance somehow
* Rear exhaust work is pretty amazing.

Put simply, this car is pretty amazing. And its on coilovers too... No sissy airsuspension going on here!

Thanks alot Dominik. jk.

Now I cant wait to get my VIPStyle mag. =)

[Dominik]

Ah yes, i realise now that that might have been a bit of a tease. It was late and i was excited and didnt realise that some people dont have a regular source of these mags ;)

I'll try to do some scans. These mags are usually hard to scan since they are so thick!

[gmckey]

I'm sure since you've got a 'regular source' you wouldn't mind getting an extra and cutting it up to make extra high quality scans for the destitute US VIP fans!

[Dominik]

Err, my regular source aint cheap... AUD$16 is alot for a magazine, even more so if i am buying it to break copywrite rules and cut it up for the purposes of posting on the internet! :)

I think i can get the scans done. The important ones are the pics of the undercarriage etc to show the work that has been done.

It also has details on another car - a Y33 with some amazing camber front and rear. Front of the car uses modified S13 silvia coilovers and S14 hub knuckles on the front. The owner also stresses what we already knew - alignment is paramount when running camber like this. He still gets 1500km/Rear, 1000km/Front before having to flip tyres, and that is with less than half of the tyre making contact with the road! IMO that is an acceptable tyre life...

[Chin]

The only problem I see with radiused fenders is the car will have to be driven slammed all the time. If you are running air and decide to lift the car for highway driving and/or carrying friends, the gap would probably look awful. As a matter of fact it would look worse than stock because of the radiused cut.

[manila_boy]

man i love that yellow wagon, not the color tho' but wheels are nice, i just love the way it looks, i'm just looking at a new perspective that an acoord can have, as a vip fan this one is on my list of favorites.