Here's my stance on wheel spacers . . .

[tekenaar]

I've been looking at, and not satisfied with, the "stance" of my ultra low mileage '75 Ascona for some time and finally decided to do something about it . . . widen it . . . with 1" hubcentric 12x1.5 spacers.

Already have 1" wide, hubcentric H&R wheel spacers on the front of my 2.4FI GT, so naturally I looked there first . . . hmmm, $150 for a pair of 25mm (~1"), 4x100mm, 12Mx1.5 studs, 57.1mm hub, ~$330 for all four wheels including shipping. Those Krauts sure are proud of that TÜV certification, aren't they!

Poking around on the net a bit more, I discovered a generic set with the same specs, but with a hub-bore of 64mm, i.e. not hubcentric, but at less than half the cost, ~$70 a pair at ezAccessory.com! Not exactly what I wanted, but close.

Poking around a little more at their site, I was delighted to find that they also sold poly carbon hubcentric rings with a common OD of 73mm and different IDs for various hub sizes, including Opel's - 57.1mm . . . $16 for a set of four!

Bought two sets of the adapters (4) and one set of the hub centric rings for a total just under $180, including shipping! . . . I was a happy camper!

Suppose you noticed the disparity between the wheel adapter's hub bore - 64mm, and the hub centric ring's OD - 73mm, huh? Took both adapters and rings to my machinist (don't have a lathe of my own . . . yet!), and had him machine the adapter's 64mm hub bore to the 73mm ring OD and, VOILA! . . . the correct 57.1mm hubcentric 1" wheel adapter! . . . and $20 to my machinist!

Just installed my new hubcentric spacers . . . they fit perfectly!

[neuropel]

Otto,
Any chance we'll see before and after pics?

Todd

[Bill Hoffmann]

Did you have to shorten or install shorter wheel studs, or do they just protrude into the "spoke" recesses of the wheels?

[tekenaar]

Originally Posted by neuropel Otto, Any chance we'll see before and after pics? Todd

. . . of the wheel adapters, no . . . of the Ascona, possibly yes.

[tekenaar]

Originally Posted by Bill Hoffmann Did you have to shorten or install shorter wheel studs, or do they just protrude into the "spoke" recesses of the wheels?

. . . with a 1" wheel spacer/adapter, no mods are required to the existing wheel studs. That said, I did run across an anomaly that's unique, I believe, to the '75 front wheel discs . . . one of the four disc-to-hub mounting bolts is longer with an unthreaded extension that protrudes beyond the wheel mounting surface.

No problem on stock setup, as it fits inside the rear of any one of the original steel wheel spokes. These bolt extensions must be cut flush with the hub's wheel mounting surface to mount the front wheels' spacer/adapters, however. Cutting disc on an angle-grinder made short work of this in my case.

[Bill Hoffmann]

Originally Posted by tekenaar . . . with a 1" wheel spacer/adapter, no mods are required to the existing wheel studs. That said, I did run across an anomaly that's unique, I believe, to the '75 front wheel discs . . . one of the four disc-to-hub mounting bolts is longer with an unthreaded extension that protrudes beyond the wheel mounting surface. No problem on stock setup, as it fits inside the rear of any one of the original steel wheel spokes. These bolt extensions must be cut flush with the hub's wheel mounting surface to mount the front wheels' spacer/adapters, however. Cutting disc on an angle-grinder made short work of this in my case.

I have wondered about that protrusion. It could have been there to prevent the use of some earlier type wheels, but it wouldn't stop you from using a 74 Rostyle wheel, which may or may not interfere with the '75 caliper. So the mystery remains.

[BQS4]

Originally Posted by Bill Hoffmann I have wondered about that protrusion. It could have been there to prevent the use of some earlier type wheels, but it wouldn't stop you from using a 74 Rostyle wheel, which may or may not interfere with the '75 caliper. So the mystery remains.

Bill-
It could be something from the assembly line, in that when at the phase where the wheel/tire is to be put on for the first time, it could be a quick "locating" point. Just a thought. But, I have seen these on 75 cars, and as Otto has stated a quick touch with a grinder makes it dis-appear

[2 Fast 4 U]

You guys are lucky , wheel spacers are a very big "no-no" here

[tekenaar]

Originally Posted by 2 Fast 4 U You guys are lucky , wheel spacers are a very big "no-no" here

. . . even German TÜV approved H&R wheel adapters?

[timemachine]

Clever fix Otto,

I'm going to save this thread for future reference...

Jim

[Gumby]

Originally Posted by tekenaar (don't have a lathe of my own . . . yet!)

Just think if you made a few dozen of these things you could pay for the lathe! Although a mill would certainly make it easier.

[2 Fast 4 U]

Originally Posted by tekenaar Originally Posted by 2 Fast 4 U You guys are lucky , wheel spacers are a very big "no-no" here . . . even German TÜV approved H&R wheel adapters?

Yes, even German TÜV approved, because the German TÜV is not recognised here in Holland.

[Tru-Craft]

Otto, nice find!
The spacers are made from billet aluminum, and only 1" wider than stock. Plenty strong enough for a 2,200 pound car. The low profile tire/wheel will be damaged before the spacer/studs break.
I have thought about widening the rear spacing on my GT for years. The front fills the wheel well area perfect, but the rear looks very narrow.
I have 14 x 6" wide wheels.
195/60R-14 tires
Any pictures of your widened GT?
Are the spacer nuts included?

Being a machinist I might make a couple 64mm OD x 57.1mm ID aluminum spacers.

$20 to modify the hubs, and spacers!
Why buy a lathe?
Thanks for the info.
Lyle

[tekenaar]

Originally Posted by Tru-Craft Otto, nice find! The spacers are made from billet aluminum, and only 1" wider than stock. Plenty strong enough for a 2,200 pound car. The low profile tire/wheel will be damaged before the spacer/studs break. I have thought about widening the rear spacing on my GT for years. The front fills the wheel well area perfect, but the rear looks very narrow. I have 14 x 6" wide wheels. 195/60R-14 tires Any pictures of your widened GT? Are the spacer nuts included? Being a machinist I might make a couple 64mm OD x 57.1mm ID aluminum spacers. $20 to modify the hubs, and spacers! Why buy a lathe? Thanks for the info. Lyle

Lyle, adapters are on my '75 Ascona . . . click on the links in my 1st post for questions about parts - direct link to actual parts used with pics! . . . and only the bores at the rear of the spacer/adapters were machined to insert the 73mm OD x 57.1mm ID hub centric rings . . . set of 4 - $16, BTW!

Years ago I bought H&R 1" adapters for my 2.4 FI GT on which I have vented rotor front discs from BMW . . . widened rotors caused some rear mount issues on rare 13" alu rims I'm using . . .

[RallyBob]

Originally Posted by Tru-Craft I have thought about widening the rear spacing on my GT for years. The front fills the wheel well area perfect, but the rear looks very narrow.

Lyle, something to consider is that the GT already has a wider rear track width than the front. It's 49.4" in front and 50.6" out back. This is rather unique in that most vehicles have a slightly wider front track than the rear, the most common exception being rear or mid engined cars. I'm only mentioning this because...while it may look better, it will make the car understeer more than it already does in stock form.

Bob

[Tru-Craft]

Originally Posted by tekenaar Only the rear bores of the spacer/adapters were machined to insert the 73mm OD x 57.1mm ID hub centric rings . . . set of 4 - $16, BTW!

Otto, now I see what you mean. So if I bore a 73mm x (1/4") deep counter bore in the surface against the brake drum the rings will work.
That's easy!
Thanks
Lyle

[Tru-Craft]

Originally Posted by RallyBob Lyle, something to consider is that the GT already has a wider rear track width than the front. It's 49.4" in front and 50.6" out back. This is rather unique in that most vehicles have a slightly wider front track than the rear, the most common exception being rear or mid engined cars. I'm only mentioning this because...while it may look better, it will make the car understeer more than it already does in stock form. Bob

Bob, good point!
On our Go-Karts I learned basic chassis setup, don't know alot, but widening does make it push (Understeer).
Not good!
The only thing you can do is slow down to make the corner............not good in a race!

We always set it up loose (Oversteer), this way it wouldn't bind the solid rear axle. Way faster through a corner, if you can catch it before it spins.

My GT has:
Front and rear sway bar.
Lowered front spring 1-1/2"
Stock rear springs.
Shocks, Monroe something?
Poly bushings.
195/60R-14 Yokahoma's

Bob, I want the car to look good, yep, getting old and I don't race on the streets as much anymore : (

My GT is pretty neutral as it is, don't want to mess it up too bad.

Things that have helped reduce understeer:
Lowered front end.
Stiffer front spring.
Rear sway bar.

I do want to widen the rear.
How about softening or removing front sway bar?
Use 1/4-3/8" front spacers?
Any thoughts?
Lyle

[Paul]

Lyle
One thing Bob has stated in the past is to widen the front by at least 1/2". You'll notice from the track widths Bob gave above the front actually needs to be widened by 0.6" to equal the rear.

The other thing that could be done is to use a different wheel offset in the rear to narrow the track. Alot of FWD autocrossers use this trick to adjust handling at different courses... as they will carry several sets of rear wheels with different offsets...

[tekenaar]

Well, I just installed a set of the same [Post #1] 1" wheel spacers with identical "hub-centric" inserts machined to fit on my sprint Kadett LS and must say that I'm real pleased with the new look and "stance" of my Kadett!

Now, to answer questions that are sure to follow, this time I did take "before/after" pics . . .

[opelenvy]

Originally Posted by tekenaar Now, to answer questions that are sure to follow, this time I did take "before/after" pics . . .

I think you should do it again with a tripod, you weren't exactly in the same spot.

[Redskinsjbs]

Originally Posted by tekenaar I've been looking at, and not satisfied with, the "stance" of my ultra low mileage '75 Ascona for some time and finally decided to do something about it . . . widen it . . . with 1" hubcentric 12x1.5 spacers. Already have 1" wide, hubcentric H&R wheel spacers on the front of my 2.4FI GT, so naturally I looked there first . . . hmmm, $150 for a pair of 25mm (~1"), 4x100mm, 12Mx1.5 studs, 57.1mm hub, ~$330 for all four wheels including shipping. Those Krauts sure are proud of that TÜV certification, aren't they! Poking around on the net a bit more, I discovered a generic set with the same specs, but with a hub-bore of 64mm, i.e. not hubcentric, but at less than half the cost, ~$70 a pair at ezAccessory.com! Not exactly what I wanted, but close. Poking around a little more at their site, I was delighted to find that they also sold poly carbon hubcentric rings with a common OD of 73mm and different IDs for various hub sizes, including Opel's - 57.1mm . . . $16 for a set of four! Bought two sets of the adapters (4) and one set of the hub centric rings for a total just under $180, including shipping! . . . I was a happy camper! Suppose you noticed the disparity between the wheel adapter's hub bore - 64mm, and the hub centric ring's OD - 73mm, huh? Took both adapters and rings to my machinist (don't have a lathe of my own . . . yet!), and had him machine the adapter's 64mm hub bore to the 73mm ring OD and, VOILA! . . . the correct 57.1mm hubcentric 1" wheel adapter! . . . and $20 to my machinist! Just installed my new hubcentric spacers . . . they fit perfectly!

I know that this is kind of old, but now that I am in the market for wheels, and many, many, many of them come in ET 35 and 40 offsets it got me wondering. Otto, Are you at all worried about the extra leverage that the wheel adapter you used will cause to the suspension components of your car?

The way i see it, the original lugs are secured tightly by the adapter and the it provides the extended lugs which then secure the new wheel, so now leverage and therefore stress is added to the externals of the system. But what about the internals, ie the different bearings, ball joints and tie rods? If the offset brings the center line of the wheel back into alignment, would that all be alright?

Enlighten me as I am lost . . . (it doesn't just have to be Otto either)

Thanks in advance,

Jay Swift

[Aardvaark]

As long as the stock track, (center of tire tread to center of tire tread easily
measured from inside sidewall o one tire to outside tire of the opposite side),
isn't widened much more then 1/2" total with wider wheels and spacers/adapters, bearing loads won't be significantly effected.
Beyond that long term durability of the wheel bearings could be a problem particularly if you drive aggressively. In the case of Otto, it may never be an issue since I understand he drives like an old lady.

[Redskinsjbs]

Originally Posted by Aardvaark Beyond that long term durability of the wheel bearings could be a problem particularly if you drive aggressively.

Ahh, see I drive like a madman most of the time (Yes, I am one of those crazy teens who everyone hates on the roads). But I think that my driving style will change once I really am driving my own car simply because I know of the expense involved to fix it. (And don't say 'what is your life worth to ya?' because remember, I am 18 so that means that I am invincible ) In particular, I am thinking about the very touchy and sensitive pinion gear in the Diff. I really don't want to have to find more of those in a long time.

I think that I'll be alright, if not, whats the worst that can happen, a wheel falls off?

[Aardvaark]

I don't see any way widening the cars track width with wheel/spacers or
wheel adapters would have any effect on you differentials durability.
The only ways to damage the rear gears and bearings on the Opels from my experience would be to run the diff low on oil or trailer the car while in gear.
The shifting back and forth while tied down on the trailer will hammer
spots on the gears from the engine and drive trains inertia.
In the '70's and early 80's I SCCA road raced my Ascona in showroom stock
B class and really hammered the whole car. The only failures on the track
where the breaking of wheel centers due to the tremendous cornering
loads and catching the edge of the track ruts. I rolled tires off of rims a couple of time despite 45-50 psi air pressurs. If you drive as hard on the street, you won't live to be 19 let alone see any differential failures.
If you do seriously hard burnouts you might though.

[Redskinsjbs]

Originally Posted by Aardvaark In the '70's and early 80's I SCCA road raced my Ascona in showroom stock B class and really hammered the whole car. The only failures on the track where the breaking of wheel centers due to the tremendous cornering loads and catching the edge of the track ruts. I rolled tires off of rims a couple of time despite 45-50 psi air pressurs. If you drive as hard on the street, you won't live to be 19 let alone see any differential failures.

This is quite an image, but have you ever seen the streets in D.C.? They are an absolute mess. I think that I am going to run with the spacers and see what comes of it.

Originally Posted by Aardvaark If you do seriously hard burnouts you might though.

Ahhh, see, I am of the drifting culture where smoke and tire spin are all a part of the game (legal of course). I don't think that I will be drifting the GT though, it is already too stylish. Goin sideways would just blow people's brains to bits!!!

If what you are saying is that it is an OK for street use, as in daily driver, then I am all for it.