Rim size with flares

[kupcar]

Hi Guys, I'm going to start a project with a 73 1.7. I have fiberglass flares to put on the front and rear. I was just curious as to what size rims will fit after the conversion. I will upgrade to 5 lug so that is not an issue. I would like to keep it looking stock so Fuchs are the only option. I do have a couple of sets, one set is 15's 7&8's off a 76 930. The other set are 16's, 7&9 also with 930 offsets. Will either of these sets work? Thanks, Jeff

[California#1]

8's are the max with standard GT flares. I'm doing the same thing. You can go as wide as 205 on the rears, or spacer in the back and go 195's all around.

Post some photos....I will be. I'm doing my wheels like RSR look or cotton finish 7's front 8's rear.

Cheers,

M-

[kupcar]

M, Thanks for the reply. I'm glad I saved the 7&8 15's. I will post some pictures as well. I've owned this car for 25 years. I am going to replace the longitudinals first and then do the body work. It should be a fun project. I have not decided to switch to a six or just do a big bore kit. Jeff

[California#1]

....hard choice. I like the six option....but the fours are just as fun. I thought about going the V8 route but I'll likely put a 3.2 in it. Here is mine before....

[kupcar]

I like the six option as well. Budget might force me to do the body and suspension first and swap motors later. I'm just finishing a 930 race car build. There is only so much my wife can take. Baby steps on this one. I have not run this car in maybe 6 years. The motor is great, only has 50k on it, but it's only a 1.7. Your car looks great, good luck with the build. Jeff

[sled9146]

Yes the 8X15's will work, as well as 8X16's. If you want Fuchs look, but even bigger, you can get Rota Fox 17's and their 9X17's also work with 255/40/17's. If you want later factory Porsche wheels, ie, 996 or Boxster, you can use the 9X17's with the 255/40/17's, but will need 52mm spacers in the rear and at least a 21mm spacer in front. Advantage of the 17's are the much better tire selection, ie Michelin Pilot Sports.

[kupcar]

I'm glad the 7&8 15's will work. I am going to keep it as factory as possible so Fuchs are the only option. I know the trend is to go to a bigger diameter, hopefully someone will still sell decent tires in this size. Last time I put rubber on these rims(about 6 yrs. ago) Kumho was making the Victoracer in that size. I guess I could always groove slicks if I had to. Jeff

[Dave at Pelican Parts]

If you try to put 205s on 8" wheels the tire guys are going to hate your guts. I'm not even sure they'll stay on 8s, for that matter.

The maximum wheel size varies a whole lot. There are different size flares available, and they can be installed in ways that allow more room or less room. And most 914s tend to be a little different from one rear fender to the other, just to make it even more complicated.

Wheel offset (or backspacing) plays a big role as well. There are some 7s that will fit under stock rear fenders if the fender lip is smashed flat (or removed) on some 914s. But most do not. There is at least one person who customized his rear trailing arms and moved the bearing inboard by some amount in order to fit regular 911-offset 7s under stock fenders.

The exact alignment also has an effect; cars with lots of negative camber can usually fit wider wheels and tires than those with zero camber.

And finally, the tire is a major factor as well. Different-width tires will take up more room or less room in the fender--and when put on wheels of different width, a given tire's actual width will change as well!

So there isn't really a simple answer to your question.

That said, you should be fine with 7s all around, and there's a decent chance you'll need spacers on one or both ends to make the wheels appear to fit better. A set of 7s and 8s off a 911 should work well, but again you may need to play with spacers to get a good fit.

Later wheels, such as off a Boxster, will definitely need spacers to fit. But you're saying Fuchs windmills are all you will consider, so you'll probably be fine with 7s or 7s and 8s. The 9s will likely work, but may require negative camber and smaller tires than you might want.

Then again, with a 1.7 engine any of the above will make you over-tired. Be prepared for even worse acceleration and braking due to the large heavy brakes and tires. The good news is you won't have to slow down for nearly any corner...

--DD

[California#1]

Thanks Dave and....nice car. I am going with a set of 7''s and 8''s Fuch's with a set of GT flares and 4 to 5 bolt adapters. What size tire would you suggest for fronts and rears? As well for weight, should I consider nylon belts over steel belted tires or would the weight saving be negligable....Should I upgrade to Miata front calipers.....

cheers,

M-

[kupcar]

Dave, Thanks for the info. I will save both sets of rims and see what works once the flares are on the car. I kind of figured there was no definitive answer on what will work. Yes the car is way under powered, a big change from what I'm used to with a race 930. It's been so long since I have driven this thing that even with the 1.7 it will be a blast. Is a big bore kit worth the effort or should I save my pennies and do the six? Thanks, Jeff

[racer]

I've seen GT flares house 16" wheels.. in fact, the car I saw was running 8x15 front with 9x16 rear for some reason.

Most GT look cars run 7/8 x 15 with a 205 front, 225 rear. Depending how long you take doing your conversion, you may find tires you want to be hard to find. Some makes offer a 205 but not a 225 or vice versa. Same with 225/245 combos. Limited selection these days when looking for smaller than 17" rims.

I had a 1.7 that I replaced with a 2056. Went from 80hp to 120hp and it was a LOT of fun. Now, if I had a massaged 930 in the garage, it would be hard pressed to be as much fun in a straight line, but carving the corners and driving a lightweight car can be its own reward.

A 1.7 to 1.9 can be a nice upgrade too. But in either case, until you are north of about 140hp, you really dont "need" the flares. Modern R comp rubber is so sticky that even 205's (vs stock 165s) are a tremendous improvement.

[kupcar]

Racer, Is that 2056 a big bore kit or is it a Raby motor? Depending on the cost that might be an option. I have been so caught up in my 930 that I've lost touch with what I wanted to do with this 914. I love projects and am getting geared up for this one, I'm just not sure how far I want to go. The car is clean, owned it since 86. I just want to play with it again. Jeff

[Dave at Pelican Parts]

The 2056cc engine is the 71mm stroke (stock 2.0 stroke) with the big-bore 96mm cylinders.

Going with 96mm cylinders on a 1.7/1.8 bottom end will give you 1910cc. It is generally recommended to get the 96es intended for the 1.8 motors and have the heads machined to accept them. The 96es that fit in 1.7 heads are very thin and not necessarily that reliable.

I personally dislike the 4 to 5 adaptors; I don't think they're as strong as we should have on a 914. I figure if you're going five-lug, you should do the job right and use the 911 front end and machine and re-stud the back.

As for brakes, you'd probably have a lot of work to put the Miata brakes on the 914 front end. I don't know of anyone who has done that, and I'm guessing the Miata has vented rotors anyway which will not fit over the stock 914 solid rotors.

--DD

[Racerbvd]

Originally Posted by Dave at Pelican Parts

If you try to put 205s on 8" wheels the tire guys are going to hate your guts. I'm not even sure they'll stay on 8s, for that matter.

T
--DD

If you try & put 205s on 8s, you're an idiot, period...
Why would you want to do that, there is no performance advantage, just the opposite, stretching the side walls weaken the tire, make it harder to maintain being seated, expose your rim (and anyone who does this with Fuchs should get a swift kick in the Nutz!!) to damage since there is no side wall to protect the edge of the rim..

I have factory 7&9X16s Fuchs with 205s up front & 245s in the rear, under Factory steel flares on my GT Clone..



My old RPM built 71 had "pulled" rear 1/4s that 8s would have, here is a pix with 225s on 7X15s at all 4 corners..

[PCA7GGR]

I ran 8X15s with 225/50 all around on my GT with no clearance issues. This set up enabled me to rotate tires (plus flipping inside/out) to any corner for maximum wear.

[kupcar]

This project is just in the beginning stages. I have been stockpiling parts for a while. The front end will definitely be 911 so five bolt can be used. For the brakes I have old bremtek calipers. They probably need a rebuild (any recommendations?) but they should fit under the Fuchs. The motor, I'd like to keep simple but with the 1.7 it can barely get out of it's own way. Not sure if doing a big bore would make that much difference performance wise. Any ideas?

Hey Byron, what ever happened to Jay at RPM? I went to school in Daytona and remember some of the stuff he was working on. Jeff

[racer]

kupcar,

My 2056 was not a "raby" engine, but as dave mentioned, was built using 96's. Carbed with 40 Webers iirc (this was 10+ years ago now. It was reallya nice motor in a stock bodied car that only weighed 2000lb "wet".

In addition to the HP was also the increase in TQ wich was quite noticeable.

If I had the time/money (oh, and another 914) I'd consider a 2270cc motor. While not cheap, I do like the TQ and "correctness" of a 4 in a 914-4. Jakes 2270s are likely in the 150-180hp range but I haven't kept up. No doubt, though, they are as expensive as a "big 6 conversion" as well.

[kupcar]

Racer, Thanks for filling me in on the 2056 specs. That might be an option. I'm just looking for a bit more umph. My 930 cures the speed itch with 330hp in a 2350 lb car. Now that the 930 is finished, I'd like to have some fun with this 914. It's been in storage forever. The info is much appreciated. Thanks, Jeff

[larrym]

different brand wheels have different backspacing

(forget ET - it doesn't tell you anything useful)

on my GT with oem steel flares - for racing - I have run BBS 8x15 and 9x15-rear (long since forgotten the tire sizes),

- also have run BBS 7&8x16's with A008 225-50 and 245-45's,

- currently run 4 7x16 Fuchs with 205-50's gForce TA's on street

also have a set 0f 7&8x15 Fuchs for certain vintage venues that use the same spacing as the street Fuchs

My car was originally fitted with "long studs" when built in Germany, where it originally ran a set of 4 8.5x15 custom light-weight steel wheels and 185-70x15's per the TUV certification

- I have always used the 24mm spacers that came on the car from Germany on the front with all wheel types, and anywhere from 15-30mm spacing on rear depending on the wheel brand and backspace


I recently test-fitted a 18x8 996 turbo-twist wheel with 245-40 tires - the rolling diameter is 24" which is same as a 185-70x15 on a period correct wheel

it does not work - needs too much spacer - on order of 3 inches cuz it has about 2.5 inches more backspace than a conventional vintage porsche wheel,