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Hi, Im pretty new at this, i hope I have this in the right place. I just purchased 71*15inch ET or offset "25" BBS rims. I was told that the right size for these rims are low profile tires that ar 205/50 or 55/ R15. Im not really sure what to do, has some :cool: body have this type of rim. Also I need spacers for these. Can somebody help me with this information, I would really appreciate it. Robert, 1971 2.4 Opel GT P.S I have the 2"inch sport lowering spring in the front suspension. Thank you
 

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Oh boy.... This is a topic that has been beaten to death in here. If you do a search on wheels, I m sure you will find a ton if information. However, just to get you going in the right direction..

A) I am sure you meant 25mm and not 25" offset.

B) Are these wheels for a front wheel drive or a rear wheel drive car? If they are for front wheel drive, they wont work.

C) The off-set is how far OUT the center of the wheel sits toward the outside of the wheel well. For example, if you want a wheel to have a nice deep dish, you might want something like a -11 offset where the center of the wheel is more inside of the wheel well. I am having custom wheels made with a +12mm for the front and a + 3mm for the rear. But they are 8 and 9.5 inch wheels respecetively.

To be honest, with all the research Ive been doing on custom wheels, I have no idea what the stock "offset" is.

I too am lowering the car with the sport spring. I am getting 16" wheels and the tire size I am getting is Front 205/45/16 Rear 225/45/16, so you should be fine with the 50 series on the 15" wheel.

HTH
 

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Sorry Thom, I have the gold BBSs on mine meant for a front wheel drive Honda. 1/4 inch spacer in front and variation on the rear discs in the rear. It's lowered two inches and it's fine.
 

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Whether front wheel drive wheels will fit or not depends on the offset -- too much positive offset and the wheels will be into the chassis or suspension. I had a set of front wheel drive wheels with a 35 offset (14x6), they fit, but I hated them because the wheel set too far in ... didn't look good and narrowed the track.

I have a set of front wheel drive wheels (from a VW Rabbit) with 33 offset that I run on my Manta (IT car) using a 1/4 inch spacer. (I would use a 1/2 inch spacer but I'd have to install longer wheel studs). They're mounted with rain tires ... so I hope I don't need them often -- but in NE Ohio, who knows what the weather will be -- I might need snow tires.

I believe stock GT wheels (13x5) have an offset of 25mm.

Ken
 

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nobody said:
Sorry Thom, I have the gold BBSs on mine meant for a front wheel drive Honda. 1/4 inch spacer in front and variation on the rear discs in the rear. It's lowered two inches and it's fine.
Thats becauue you have the spacers... Without them your SOL. But you are correct, FWD will work with spacers if it has the right offset.
 

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wheel offset

Robert- What you are looking for is a wheel back space of 4" - 4 1/2". This is the distance from the BC back face to the back of the tire. It has been mentioned befor so do a search. 7" rims usualy require +20mm or less offset to give you a 4" - 4 1/2" backspace. You should be ok with 5 - 7mm spacers
 

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I think I'm jealous!

Hey Robert-
I'm new at this too... I will be having some 15" wheels made in the near future... I've read 90% of the wheel threads (many twice or more)... I've calculated available tire sizes, and measured for clearances at each corner... and my GT replaced a '79 320i... which qualifies me to say "I may know just enough to be a danger" if you take this as Opel gospel:

Gotta know width of your rims (not overall, but from where the tire bead seats). Did you mean 7"x15" (instead of 71*15")??? 'cause 25mm is like 1 inch... and 1" offset (offset is from width middle of wheel) on 7" rim leaves 4.5" hanging inside. The "why" omitted ('cause it's all been said), "I" believe there's room for a 7"x15" rim with your offset... but 20mm is verified.

In a different thread a few days ago you mentioned your rims are from a BMW... (but not which one)... hopefully from a '70s-('81?) 318-320i (- later & larger series used different offset & bolt ptrn./qty.) . Anyway, count the bolts. If they're 4 bolt BMW, then they're 4x100 & fit to your hub directly (but center themselves to the Opel studs, rather than a shoulder on the hub... & partially why I've decided for a lug-centric wheel myself). If 5-bolt, then you'll need an adaptor... & be poking the wheels further outboard. (turn your steering wheel 1/2 way to left lock and checkout how little clearance is between back of LF tire and wheel well already!) So far as the tire profile, I'm picking a 50 & get a little more room.

Sooo... if I owned a set of 4x100 6-7.5" 15" rims w/25mm offset... I'd be fitting them on the GT!

HTH
-Dan
 
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