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Posted by: monkei Jun 18 2006, 01:07 AM

ive seen many 17s on 914s and it seems like the profile could allow for 1" larger rims and still have some tires. about how much sidewall is left with 17s?? how much more jarring is a 914 with 17s as compared with 16's?
anybody have pictures of 18's on a 914?

experiences/facts would be nice. opinions arent of much use, i dont much care how you think it will look. and if you havent ridden in a 914 with 18's, im not sure you could tell me much about how it would ride either.

i talk big, but someday maybe ill have the big money; i intend on making this a track car, hopefully somewhere in the range of a 200mph topspeed. i think some lightweight 18s would be appropriate for such a purpose.

Posted by: banksyinoz Jun 18 2006, 01:24 AM

im with you champ im thinkin 18s also and these are what ive priced was thinkin 18x8 + 18x10 will have to severely modify guards

i know not much use in info but just encouragement

these may be close to 18


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Posted by: monkei Jun 18 2006, 01:26 AM

wasnt expecting any support. alright i gotta tell somebody; i fould 993 18" rims for 250$ i cant afford it but i think i have to do it. ones got curb rash but i dont care. i was looking at 700$ as a best price on 993 17's.

that car is sweet, cant tell if those are 18s or what, but now im reconsidering that style of flare again

Posted by: banksyinoz Jun 18 2006, 01:28 AM

i would check wat spacin is needed and if their cheap enough go for it

Posted by: monkei Jun 18 2006, 01:30 AM

how do i go about/who do i ask/where do i have to go to find out what kind of spacing will/wont work. im planning on acquiring 993 susp/brakes down the road.

Posted by: banksyinoz Jun 18 2006, 01:31 AM

i have 16x7+16x8 as in pics but with the more rigid ride i could run a diffrent spring shock set up than most to retain a better ride or just put up with it i guess


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Posted by: banksyinoz Jun 18 2006, 01:34 AM

check on the forums here there is a wheel spacing chart ive seen it before or maybe some one has tried them

i want to put it to the jap cars and keep up with the times how about u

Posted by: monkei Jun 18 2006, 01:39 AM

are you referring to subaru??

im considering a number of powerplants including subaru 4's and 6's but im getting more into the idea of a 32v 928 motor to put the chevy guys to shame as my ultimate goal.

Posted by: sj914 Jun 18 2006, 01:39 AM

I think 18's would look great on a 914 that had the suspension all sorted out.

The only problem I saw with going with 18's is to make them look good you'd have to lower the car a bit, but not much. If you look at my avatar it shows my project minus the fender with an 18" while the shock was bottomed out.

Instead of 993 brakes, why not go with boxster brakes.

Posted by: Andyrew Jun 18 2006, 01:42 AM

Yup... You need a good suspension that wont bounce like crazy for the pot holes..

Im going 17's on the front, because they get the biggest hit in case of an unexpected pot hole... and 18's on the back (hard to find 17's in 10's or bigger for a decent price)

and as to how much more jaring is it?

ran 17's on the stock 944 turbo for a while... you do notice whats on the road... then we switched to the polished 16in fuchs... smooth ride...

WAY opposite for the 944 turbo race car... put the 17's that were on the stock car... on it.. you feel everything... unfortunately...

Posted by: monkei Jun 18 2006, 01:44 AM

lowering is definitely in the plans. would boxster brakes and rotors work with 993 hubs or would i graft in all the boxster stuff?

does anyone know what a good backspacing/offset would be for a set of 993 18s to be fit on a teener? whats the offset on the wheels in your avatar? those look like boxster wheels?

Posted by: banksyinoz Jun 18 2006, 01:45 AM

yeah ok you got me im a suby guy ej20t with auto here in aus if ya cant beat em join em its all jap imports here in queensland but anyway im all for the 18s tyres are a bit pricy on the 18x10s but hey wat the heck

i saw that avatar i did wonder


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Posted by: Mueller Jun 18 2006, 01:49 AM

someone asked the same question last year, a few pictures had been posted...most of the cars had real racing tires so no far comparison to street tires as far as ride and such....also they had "real" race suspensions that no one would dare drive on the street with such stiff springs and setup....

you better have some serious power to turn those wheels, your car will be a slug if you got a stock 2.0 or even worse with a 1.8

....figure 50 pounds or more EACH corner !!!!!!

Felix (twin turbo V6) and Roger Grubb (V8) as well as a couple others have 18" rims on thier 914's, Roger has not mentioned anything about the ride being too bad...key is good quality shocks and properly functioning suspension bushing or bearings....

also keep in mind that new replacement tires start at $200 per tire for good 18" tires...the wider, the more expensive (and heavier)


my car with 205/40/17's rides as nice or nicer than some cars I've driven that 15" or 16" rims and tires....

Posted by: banksyinoz Jun 18 2006, 01:49 AM

not sure but this was another diagram (might help)


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Posted by: monkei Jun 18 2006, 01:51 AM

so if i bought the 993 18" rims id want to find the matching hubs from the vehicle the wheels came on??

Posted by: sj914 Jun 18 2006, 01:55 AM

What you need to figure out is how you want to go about your five lug conversion first, do a search for those. Once you get the five lug hub, you can pretty much bolt on a 911 sc rotor(20mm thick) in the rear and get the caliper adaptors for the boxster monoblocks. For the front you would need to get 911 struts that have a 3.5" caliper mount spacing(either bilsteins or koni and some boges i think), 24mm thick carrera rotors then the caliper adaptors for those and the calipers.

Posted by: Mueller Jun 18 2006, 01:55 AM

you'll have to spend another $10,000 just on that motor to come close to most of the Chevy V8 conversions...the 928 is not all that as is and in order to get real HP numbers from it, open your wallet

the 18" 993 rims will not fit without flares at least in the rear....the 993 or the the Boxster suspension will not work without MAJOR fabrication and engineering to get everything just right....

Posted by: Mueller Jun 18 2006, 01:57 AM

no....all Porsche 5 lug are 5x130.......the 993 rims will bolt onto an early 911 if you want (too wide, but you get the point)

Posted by: banksyinoz Jun 18 2006, 01:58 AM

god i love this club so much experience saves so much time and money

Posted by: monkei Jun 18 2006, 01:59 AM

alright, thanks for the reality check. will the 18" 993 rims mount to 964 parts then? are pre 993 parts good enough for a high speed track car (180+mph) or would i be better off doing the required work to fit more modern components?

Posted by: sj914 Jun 18 2006, 01:59 AM

Well saves time, I don't know about the money saving parts especially for what I want to do.

Posted by: banksyinoz Jun 18 2006, 02:01 AM

yeah im hearin ya but it sure helps to get the right parts first

Posted by: monkei Jun 18 2006, 02:12 AM

so i plan on flaring, lowering, and getting the 5lug stuff as well as coilovers stiff springs and all that. i just want to be pretty sure i can make it work. i work in a machine shop so some fabrication is possible but im hoping that with the right rotors hubs and spacers/offsetting i can fit these rims. 18x8s and 18x10s.

Posted by: sj914 Jun 18 2006, 02:14 AM

Which rims are those? Depeding on the wheels offset and back spacing, you're looking at spacers between 1" - 2.5"

Posted by: Mueller Jun 18 2006, 02:18 AM

you cannot use the 964 suspension....yes, the rims bolt on, but the suspension is too far off from being even close to working with the stock tub.........You'll need flares..period, so if you have flares, the rims will fit with spacers cause you'll have to have spacers as well....at least the spacers I know you can make at your shop.....

Posted by: monkei Jun 18 2006, 02:21 AM

heres what they look like. they resemble wheels sold as "turbo" or "boxster" wheels on ebay. ill have to contact the seller about offset numbers.


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Posted by: monkei Jun 18 2006, 02:24 AM

i also actually have drawings for 5 lug hubs that i might be able to get turned. im not sure but i think theyre designed to mount on a 4 lug spindle.

so what do most 914 owners do when they upgrade to 5 lug? just change hubs and keep 914 specific struts and mounts?

Posted by: sj914 Jun 18 2006, 02:27 AM

I think with those wheels you would need really thick spacers to get them to fit on the car.

Posted by: Mueller Jun 18 2006, 02:28 AM

right now it does not matter what the offset is, the size of the spacers will be partly dictated by the flare...right now, who cares what the offset is,,,,,you'll need spacers....unless you build a tube frame car and use a radically different suspension...then you can install them with no spacers...

so, yes, the rims can work, and those have been mounted before on a 914...now just save your money....of course now most of the newer 997s are coming out with 19" rims so just wait for someone to ask the same question all over again

Posted by: monkei Jun 18 2006, 02:37 AM

does anyone make 18s with a bakspacing brought in toward the hub a fair amount to reduce the amount of spacer that would be required?

Posted by: Dr. Roger Jun 18 2006, 02:41 AM

Build it, they will come!

Posted by: Dr. Roger Jun 18 2006, 02:43 AM

oh, and to answer your question.

to the best of my knowledge, no. not in a modern porsche wheel.

spacers are required.

Posted by: monkei Jun 18 2006, 02:46 AM

thats sweet.

how much spacer on yours? whats the wheel width? what hubs/rotors? suspension? are those gt flares i see?

Posted by: Mueller Jun 18 2006, 02:50 AM

sure, expect to pay at a minimum, $500 per rim for 3 piece wheels....

as far as I know, nobody exept for Ron Mistaks (sp?) car is running a suspension more modern than 1989 911 stuff (911, not 964, since both had been made in 1989)....

Posted by: Dr. Roger Jun 18 2006, 02:54 AM

wheel width: 8's and 11's

hubs and rotors: complete 911 front end. rear is spaced 914 caliper with vented 911 rotors with reduced diameter to fit the caliper and maintaining E brake (street car).

flares are sheridan.

see the last pages of my progress thread for more in depth answers to all of your questions http://www.914world.com/bbs2/index.php?showtopic=33301&st=300

Posted by: Mueller Jun 18 2006, 03:02 AM

ouch...those rear tires are almost $400 each.......wow.....

Posted by: monkei Jun 18 2006, 03:04 AM

so i could do the turbo rims and spacers until i can afford to do a full tubeframe right so i can mount 993 or later suspension and then ill buy the superlightweight three piece 18s...or maybe 19s

i still would like to know, and im sure you could answer mueller: would a late eighties 911 5 lug hub and 914 aftermarket struts/coilovers with stiff springs with bearing-trailing arms and upgraded torsion bars sway bars be good enough for a 180+mph track car? or will i need a full tube chassis tied to the suspension as well as motor and transmission. i had planned on doing a full length roll cage and perhaps tying it into the motor/trans mounting but i had intended on leaving suspension attatched to unibody. im intrigued by the thought of going as far as tying the cage to the suspension as well but even more so by the idea of perhaps using the cage as an opportunity to mount more advanced/capable suspension and drivetrain maybe even one with a 928 powerplant.

i know some of the expenses involved but i dont know about everyone else im taking it slow and im trying to do the right research and do the job right the first time. its going to be a looooooooooong project. im only in rustoration phase. but the wheels are a deal at 250$ and i feel like itd be a good start....

Posted by: Mueller Jun 18 2006, 03:13 AM

I'm sure the stock based suspension "could" be modifed to work will approaching 180 mph, but you would not catch me trying to go that fast in anything related to a 914...even less willing to do it in a full caged car with 993/996/997 or more modern suspension unless it was put together and tested by a professional racing team

Posted by: turboman808 Jun 18 2006, 03:29 AM

Yeah after looking around ALOT I kinda realized that 18 inch tires are gonna be expensive. Probably not gonna gain any performace there either with all the extra wheel weight. In 16 I found you are very limited to the wheels you can use so again it seemed the tires where a bit exspensive. Not to many companys make multiple width 16s. Seems 17s are the best choice.

Posted by: banksyinoz Jun 18 2006, 04:15 AM

roger is the man read the thread cheers

Posted by: Aaron Cox Jun 18 2006, 11:04 AM

you will need lots of spacers... ($$$$$$$$$$$)

Posted by: nebreitling Jun 18 2006, 11:20 AM

hell, spacers are the least of your worries. for that matter, so are wheels -- even though they are critical. i think a 180-200 mph 914 would be fabulous, and i think you could do it for under $100k if you did a majority of the labor.

anyway, i'm with mueller -- i'm sure you could get a 911 suspension working enough for 180 mph, but i'm not sure i'd want to be in the car. tube-frame, double-wishbone, aero developed, 600+hp might do it. at that point, you already built custom wheels.

until you're ready to pull the trigger at that level of development, i'd try to settle for for the more commonly available 5-lug 17" wheels. keep in mind that they will hurt your performance in all respects compared to a similar 15" wheel.

Posted by: DonTraver Jun 18 2006, 08:15 PM

Don't want to rain on your parade, BUT. A lot of the sanctioning bodies (clubs) will not allow spacers on track cars. Autocross, no problem, time trials, club racing, a problem.

Just a bit more to investagate before you spend a lot of time, sweat, and money.

Good Luck, don

Posted by: monkei Jun 18 2006, 09:43 PM

"until you're ready to pull the trigger at that level of development, i'd try to settle for for the more commonly available 5-lug 17" wheels. keep in mind that they will hurt your performance in all respects compared to a similar 15" wheel."

good to know about the spacer cost and rules. are you referring to 18s or 17s above? how would a 17 hurt performance over a 15 in any way other than weight? i would think the lower profile would allow for much better cornering...?

Posted by: Andyrew Jun 18 2006, 10:10 PM

The added weight towards the outside of the wheel makes for more unsprung weight.. acutally its rotating mass.... When you add 30lbs to the vehicle its a whole different ball game then adding 30 lbs of rotating weight... Because now, the engine has to actually rotate that 30lbs extra, and not just push it...
Same goes for if you push the weight farther outwards.... Take a 2lb ball... attach to rope.. swing it at 6inches... then swing it at 12inches...

Figure a ~3% loss in hp per inch you go up in wheel diameter.
Same goes for cornering... car needs to jump over the weight hurdle to rotate and such.. also same for brakes... More stuff to stop...



FYI... rolled around with the 18's today.. AND 275 lb springs in the back... smooth ride. but I could feel just about everything... yet.. it wasnt unpleasant.. just noticable (very defined.. I could feel a crack in the pavement.. but it didnt kill my back or anything.)

Posted by: banksyinoz Jun 19 2006, 06:01 AM

well im gonna change stud pattern its just too expensive to get wheels here if i redrill to 5x 114 (ford, toyota, mazda nissan) i can half the cost
then get what i like in whatever offset

icould have a set for every occasion eh

22in giovanni chromies (pimp my ride style)
how slow would that be then

Posted by: groot Jun 19 2006, 06:49 AM

For ride comfort the diameter has less to do with it than you may think. Tire construction has more of an influence on ride comfort.

You can get more lateral grip from a 15" tire in some circumstances. Bigger doesn't mean better, just bigger. And before you say, "He's doesn't know what he's talking about" please understand that I do this for a living.

I am a vehicle dynamics development engineer for the 2008 Focus; which includes handing, steering and ride development.

On the Focus, the 16" Pirelli P6 is more comfortable from a ride perspective than the fuel economy-minded 15" Hankook and I have data to prove that. The sidewalls on the 16" Pirelli are much stiffer than the 15" Hankook, but the larger tire rides better. We do make damper adjustments to accomodate the differences in the tires, and even after that, the 16" Pirelli is more comfortable than the 15" Hankook.... for the Focus.

Posted by: Dr. Roger Jun 19 2006, 06:37 PM

keep in mind, i chose to put those wheels on knowing that i'm increasing unsprung weight but i'm probably pumping out >350HP, and i'll never go on the pro circuit road racing. maybe a little A/Xing but , God willing, a summer time daily street car... on steroids. =-) LOL

if i was running a 1.7/1.8/2.0 i wouldn't go larger than 17's and no wider than 10's in the rear.

if i was running a pumped up /6 i would get something fat and sticky.

Posted by: byndbad914 Jun 19 2006, 07:48 PM

here is a quick impression of a 914 at 180mph...

http://vehiclecraft.com/petitporsche.mpeg

Shove 525HP in and try going 140 in 3rd gear and see how stable that feels with stock suspension!! The front of my 914 sinks enough due to the wind pressure/lifting of the rear that the bump steer both front and rear f's with the toe enough the car wanders down the front straight at Willow Springs. That was with a spoiler and Sheridan body kit.

My tube car project is adding a wing, a front splitter and we are custom fabbing all the suspension mounting points to use Bilstein RSR struts and a 5-link rear to try and overcome all that crazy (read that as shitty) Porsche designed suspension/aero shape.

I am hopeful to just get near 160 without wandering the whole width of the track. 914s are NOT well designed from an aero standpoint. But with flares, wing, low stance and wide wheels, they look badass

As for wheels, go with what you like for looks for now. I wouldn't go over 17" as the tires get large in diameter. A decent 18x11 would run a 295mm tire. At a 35 series sidewall that tire would have an overall diam of 26", which is a big tire to fit under that car. I have 25.3" diam rear tires with a low car and that is a big ass tire overall diam wise IMO. You can get a 295 in 17" and have 25" diam which is mo' reasonable.

Check out Bill's car - similar HP to mine and same body kit, but his is actually done and painted and has 18" wheels. Looks pretty good. I like the look of a little more tire sidewall, but he definitely has the "rubberband" tire look that is really popular these days.

Posted by: Andyrew Jun 19 2006, 07:52 PM

Im trying to go for 27in tires... The tires look TINY compared to the rims on my car right now.. (car is a little tall... but still) Lemme upload a pic.

Posted by: Dr. Roger Jun 20 2006, 08:57 AM

hey andyrew,

love to see the pic of what your car currently looks like... =-)

Posted by: WRX914 Jun 20 2006, 10:06 AM

My 17's




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Posted by: Brett W Jun 20 2006, 11:29 AM

One thing to keep in mind when building a race car is the fender top /bottom clearence. When you put a tire that is 24-26in tall under our fenders and then lower the car you will hit the bottom side of the body under the strut mount. At that point you will have two options eliminate the strut or move the wheel further out.
By moving the wheel further out you will have problems with scrub radius and then you will have other issues. Issues you don't want to have at 200mph.

Look at a modern car and notice how much room there is inside of the fenderwell. The chassis are designed to compliment the much larger wheels available now days.

Posted by: turboman808 Jun 20 2006, 11:45 AM

Just bought some used 17 inch twist. ALso came with some old tires which is good so I can make sure and order the right size spacers.

Posted by: Andyrew Jun 20 2006, 05:29 PM

I dont think 18's are too big...

Keep in mind my car needs to be lowered about 2 inches.

Posted by: lybones Oct 20 2006, 11:13 PM

I know this is an old post but , I've got 18x9 and 18x10.5 on my teen. I used a 1.5" spacer for the front and a 1/8" spacer for the rear. check out pics on my v8 thread.

Posted by: JPB Oct 21 2006, 07:33 AM

I deny all of your claims and reject this so call improvement. It is just wrong and all good looking bling bling and and , I don't accept it so I don't desire this kinda sweet sacrilege!

I hold a personal Jehad against this perversion of attractivness.

Posted by: Mr.C Oct 21 2006, 09:38 AM

Here's a picture of the 18s I picked up for my project. They are going to be pretty much just for the street. I could of had a 87 928s, but I was two days shy. I'll settle for the wheels.
The 18s
Front 225/40/18
Rear 265/35/18


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Posted by: rick 918-S Oct 22 2006, 08:54 AM

Anyone have a source?

I wonder who could cut 18" Fuch wheels from a solid billet? You can have wheels made from 16' centers but they kind of look like the centers are too small. Or maybe just have custom centers with longer paddles made.....

Posted by: JPB Oct 22 2006, 09:07 AM

I in your general direction as this Jehad continues to rebel against your sweet temptations. You have no pull against the faith of my resistance.

I return now to my rock and sand cave emanating holy golden rays of rightiousness!

Posted by: Mueller Oct 22 2006, 09:10 AM

these in the picture are 17's, but no reason 18's couldn't be made the same way.

They look like Coddingtons, but there are other companies that make rims the same way....who makes the rims for Foose??...figure about $500 - 700 a pop..I have custom 20's on my truck, 2 piece design with the center billet welded to the outer half.

Posted by: JPB Oct 22 2006, 09:28 AM

Dammmmmmmmn!

Your rims are outshinning my holyness.

Posted by: Mr.C Oct 22 2006, 11:41 PM

I'll trade you this set of wheels for your virgins.

Posted by: Walter Oct 23 2006, 02:56 AM

Maybe optional (=18") boxster rims are a posibility for you guys?
For those cars, 18"'s were made a tad smaller in width. This way I searched long for 7,5 and 9J x 18 Sport-classic II's (BBS) and found a set :-)
They have 225/35 tires and are actually a tad lower than my 17" rims (with 205/50/17) before.