15x10 and 15x14 backspacing.

One thing I’ve noticed on a lot of GT4 and 5 non-factory cars is they are jacked up way high like 4X4s. On a normal Pantera and factory 4 and 5s the lower back A arms are normally pretty close to parallel to the ground and that’s the way we like them. They even handle best that way with a slight nose down stance of about ½ degree measured along the bottom of the pinch weld. Some non-factory 5s I’ve seen are way jacked up in the back and even further in front so they are running up hill.

I’m not sure how they get messed up like that but it must have something to do with getting the fender flares in the wrong place or they started work without the correct GT wheels, etc. So expect the first thing to do would to be to get the correct GT wheels and tires and get the car setting at the correct height and then start cutting. Not something I could do though! Another thing to consider is a Pantera must be moved after being jacked up for the suspension to settle to the normal ride height.

You would think the flares would only fit in the correct position but apparently that is not the case. Or there could be non-factory flares that are not the correct shape or size floating around. It is a bit of a mystery to me but one I will never need to worry about.

Mike

quote:

Originally posted by Pantera 1887:
One thing I’ve noticed on a lot of GT4 and 5 non-factory cars is they are jacked up way high like 4X4s.

Mike

That is one of the reasons I would like to go for 15" wheels. I think the reason that many cars look like what you describe is that the bigger inch wheels allso has a taller side no matter what tires you use, and if you want them to fit correctly under the flare, it means all the extra hight of a 17" or 18" as opposed to a 15" tire will transform into added groundclarence, and that I don't want...

quote:

What is "tire safety bead" on a wheel?

Extra ridges on the inside of a wheel that help prevent a flattened tire from sliding all the way to the center of a wheel.

This wheel has them.

The rear A-arms do not sit parallel to the ground on my current '74. They never did on my earlier Pre-L. If I lowered the car (I have) to where the arms are parallel, the rear negative camber would be ridiculous.
You'll never get 15" GR4 rims to fit a narrow body car. Not even remotely close. AND, they are north of $6k for 13's, more for the super rare 14's.
The vendors all sell 10 spoke repro's and you can have them bead blasted so they look closer to original.
Will

quote:

it means all the extra hight of a 17" or 18" as opposed to a 15" tire will transform into added groundclarence, and that I don't want...

Hmmmm.....

The stock rear Pantera 15" tires were about 26.5" tall.

335/35x17" tires are .... about 26.5" tall.

I run those, with 245/45X16" on the front and my car sits as low as any I have ever seen. How your car sits is not only a matter of the tires. It is a somewhat a function of tires, to be sure. But adjustable height springs and shock length are also very important.

You can easily have a low car with large diameter tires. Just takes planning.

Larry

quote:

If I lowered the car (I have) to where the arms are parallel, the rear negative camber would be ridiculous.

The workaround for that is adjustable rear, upper a-arms.

Was your car this bad?

Larry

quote:

Originally posted by 4NHOTROD:
The rear A-arms do not sit parallel to the ground on my current '74. They never did on my earlier Pre-L. If I lowered the car (I have) to where the arms are parallel, the rear negative camber would be ridiculous.

Will

Are you sure about that? Looks pretty close to me and this one is typical of what I’ve seen on factory GT5 cars. Mine is a bit lower and than this one and the camber is fine. Expect there could be cars with collapsed wheel houses and they would be a problem for sure.

There are lots of examples of jacked up 4s and 5s on the web but I’d rather not post them here.

Mike

quote:

Originally posted by 4NHOTROD:
You'll never get 15" GR4 rims to fit a narrow body car. Not even remotely close. AND, they are north of $6k for 13's, more for the super rare 14's.
Will

Unless I missed something I think he is going with flairs.

Mike

Lets start first with this: Yes, as Pantera 1887 guesses, I will put flares on my car.

So, to big-wheels ride-hight. As 1887 says, there are a few high riders out there, since not all builders are planning and executing as good as 4HOTROD and others do. I dont want to be among the ones that plan badly..

As for how tall the tires is. Standard body cars might have 26,5" high tires. 335/35-17 tires is betvine 26,2 and 26,5. That is just fine, but when you have flares, and the wide rear 345/35-15 is no more than 24,9" tall you have a difference og apr. 1,5"!
If, as some "4x4" has, the upper part of the tire has the correct amount of air betvene it and the flares, that 1,5" extra tire will have to lift the whole car.



SO, back to what I need: Backspacingmeasurements for the 10" and 14" wheels. Anyone?

There really is no singular answer as it depends on some factors and preference...... but there are a lot of previous threads on backspacing, with lots of opinions. Also be aware some people (and most wheel manufacturers) quote backspacing to the inner tire bead, others to very outer lip of the wheel.

What we really need is a sticky with wheel + tire type, full wheel dimensions, flare type and supplier and a couple photos of the car that they are mounted on.

There is fine balance between havng the wheel too far under the flare (funny car syndrome) and having it out at the edge requiring higher ride height. On my factory GT5 to keep the car ride low the front tire hits the flares over large bumps and consequently I have cracks in the flares.

Flares from different sources/vendors and type (steel or fiberglass) are often different width, affecting wheel backspacing choice.

FWIW the 10" Campi's are quoted as having 4 5/8" backspacing and the 13" wide are 5.5" backspacing (to outer lips). Th 14" width wheels always appear to me to be wider on the body so maybe they have the same backspacing and the extra 1" is on the outside.

My aftermarket Kodiaks for the GT5 and GP4 (10" & 13" widths) are 4.625" front and 4.75" rear to tire bead lip.

Julian

quote:

Flares from different sources/vendors and type (steel or fiberglass) are often different width, affecting wheel backspacing choice.

FWIW the 10" Campi's are quoted as having 4 5/8" backspacing and the 13" wide are 5.5" backspacing (to outer lips). Th 14" width wheels always appear to me to be wider on the body so maybe they have the same backspacing and the extra 1" is on the outside.

My flares is fiberglass, and will be made by myself to fit as I intend them to do. No readymade parts here... Custom is the way to go

Wheels: If I want to push the fronts to the limit (as wide as I dare..), I will need
BS of 4,5 or less? And with 1" more on the rears, and a BS on the 13" of 5,5", does that mean that on the 14" wides it still is a BS on 5,5"?

http://pantera.infopop.cc/eve/...62/m/6830076675/p/20

See my last post so far on this tread.

Will[/QUOTE]Yes, the A-arms on the pictured red car are very close to parallel. Maybe it's different on factory GT5's as opposed to narrow body cars?
Watch the latest video of RobertVegas'orange car. At the end of the video, you can see his A-arms which are not parralel at all.
Would it make a difference what size wheels were used for camber? I don't think so. Camber angle doen"t change with diff size wheels. Odd that it is that much different.
"DUH" on my part for not realizing that the project is obviously going to have flairs. Sorry for reponding that widebody wheels wouldn't work on a narrow body.
Will

Are you sure about that? Looks pretty close to me and this one is typical of what I’ve seen on factory GT5 cars. Mine is a bit lower and than this one and the camber is fine. Expect there could be cars with collapsed wheel houses and they would be a problem for sure.

There are lots of examples of jacked up 4s and 5s on the web but I’d rather not post them here.

Mike[/QUOTE]

I’m not absolutely sure but as I recall PI MotorSports had some challenges getting the wheels to fit on RobertVegas' orange car and had to jack it up. Not sure, but isn’t it a GT5 clone?

Mike

Yes, I beleive ita a clone. That was my question. Maybe different between narrow bodied cars and factory GT5's? The pic you posted is a factory GT5 yes?
Will

" The rear A-arms do not sit parallel to the ground on my current '74. They never did on my earlier Pre-L. If I lowered the car (I have) to where the arms are parallel, the rear negative camber would be ridiculous."

Will I agree ... if the rear a arms are parallel to the ground the shock mounts need to be raised otherwise they do not have the proper travel distance .. they would be close to compressed. Also the mounting point needs to be raised on the upper rear a arm because the result is any lateral movement has an extreme effect on the camber of the rear wheels. To slam the car down to the ground its going to take some work to make it also handle properly.

Ron

quote:

Originally posted by 4NHOTROD:
Yes, I beleive ita a clone. That was my question. Maybe different between narrow bodied cars and factory GT5's? The pic you posted is a factory GT5 yes?
Will

Yes, factory GT5.

Mike

quote:

Originally posted by accobra:
" The rear A-arms do not sit parallel to the ground on my current '74. They never did on my earlier Pre-L. If I lowered the car (I have) to where the arms are parallel, the rear negative camber would be ridiculous."

Will I agree ... if the rear a arms are parallel to the ground the shock mounts need to be raised otherwise they do not have the proper travel distance .. they would be close to compressed. Also the mounting point needs to be raised on the upper rear a arm because the result is any lateral movement has an extreme effect on the camber of the rear wheels. To slam the car down to the ground its going to take some work to make it also handle properly.

Ron

The lower rear A arms on my car and many others are close to being parallel to the ground. It is a tad lower than factory GT5s I’ve seen. The coilovers are a bolt in Koni system from Pantera East and they have lots of room to compress without hitting the shock snuber. Here is the info on them and the installation pics http://www.panteraplace.com/page212.htm . I don’t know what else I can tell you about ride height, it works for me and many, many others. And my car is really not low compared to some I’ve seen.

I guess the point I was trying to make, is if you are doing a GT5 clone, get the correct wheels and tires, get the ride height correct and then start cutting. Not something I’ll ever need to do!

Mike

I am wondering if they have ever existed, those 14”x15” rims. I think they where talking about the outside dimensions. The outside dimension of a 13”=14”. Otherwise what tires where they using?

I do have a set of early Campagnolo's without inscriptions and a Technomagnesio rim with inscription 13”K x 15”K ET 37.5 and an other Technomagnesio rim with 13K X15CH ET 24.5.
But they all have the exact same dimensions.

There were 14" wide rear campys for the race GpIV cars. I saw a set. That means they measured 15" wide - outer bead to outer bead

your marking of ET 37.5 is equal to 5.5" backspace on a 13" rim (it is actually -37.5 as they have a negative offset)

The ET 24.5 equals a 6.5" backspace if it applied to the 14" wide wheel. It makes no sense if applied to the 13" rim as they would be way to far inset.

I have a custom set of wheels that are 4.8" backspace (front) and 5.0" backspace (rear) and they are too far inward on GpIV fiberglass flares. They need to be moved our a good 3/4 inch both.

To compound the offset/backspacing some GT5's had wheel spacers fitted from the factory.

Julian

My GT5-S had spacers from the factory behind the original Campys. I mistakenly gave them to the person I sold those wheels to. I've had assurances that I'd get them back many times, but it's been 5 years already and I think at this point I'll have better luck waiting for the second coming of Christ.

Michael

Okay I took measurements and all tree different rims are ET 37,5. There is a 5mm spacer and it really looked right when assembled.