Firehawk offset vs. 17" GTA/crosslace offset
#1
Firehawk offset vs. 17" GTA/crosslace offset
So I see the Ronal/Firehawks are all 0mm offset, and the 17" GTAs are all 12mm offset. Why the difference? Is it just a random difference, or is it on purpose. Since Hawk's brought 'em to market, I figured they were to their specs, so it was probably on purpose.
I know the GTAs are 9" vs. 9.5" for the F'Hawks, and I haven't done the EXACT math, but I just figured 0mm all around was pretty much the accepted thirdgen aftermarket offset, without running a mismatched set like stock.
I know the GTAs are 9" vs. 9.5" for the F'Hawks, and I haven't done the EXACT math, but I just figured 0mm all around was pretty much the accepted thirdgen aftermarket offset, without running a mismatched set like stock.
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Re: Firehawk offset vs. 17" GTA/crosslace offset
12mm is essentially 1/2" inch, and the wheels are different widths, so I would think that is the difference. I think they send one of them with spacers though? I can't remember if I got spacers with the crosslace wheels or not
I have the 17" wheels and I have some real Ronal wheels, so I could measure those and let you know. Ronals are on the car and the 17" Hawks are in the bedroom upstairs.
I have the 17" wheels and I have some real Ronal wheels, so I could measure those and let you know. Ronals are on the car and the 17" Hawks are in the bedroom upstairs.
#3
Re: Firehawk offset vs. 17" GTA/crosslace offset
Nah, no need to measure, I was just curious. Hawk's "suggests" .25" spacers up front with the F'Hawks, and they said they include front spacers with the GTAs, but didn't specify size.
I've been talking to Mark at 6LE about wheel sizes and offsets as he gets set up to make a run of those new wheels. I was just curious as to what sizes all these various wheels are.
I've been talking to Mark at 6LE about wheel sizes and offsets as he gets set up to make a run of those new wheels. I was just curious as to what sizes all these various wheels are.
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Re: Firehawk offset vs. 17" GTA/crosslace offset
Hawks are 17x9 too. IIRC, The spacer is for use with standard 10.5" brakes.
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#8
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Re: Firehawk offset vs. 17" GTA/crosslace offset
The Ronals came with concentric 1/4" wheel spacers too, and it was to clear the tie rod end. The inside edge of the rim on the Ronal is square, unlike a traditional wheel, so it would hit the TRE. I would imagine the Hawks replicas are similar. Funny thing, I offered Hawks to borrow my concentric spacer so they could replicate them exactly instead of the cheapoo ones they offer with the wheels, but they only wanted it if they could keep it. Didn't make any sense to me.
#10
Re: Firehawk offset vs. 17" GTA/crosslace offset
Typin quick from my phone... my understanding was that width measurement was the actual rim, but that didnt account for .25" lip on each side. This was a given. Are FHawks the only wheel that acounts for the lip too? .....or are the new GTAs actually 8.5" +.5" for lip? Ive just never seen it written that way.5
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Re: Firehawk offset vs. 17" GTA/crosslace offset
Typin quick from my phone... my understanding was that width measurement was the actual rim, but that didnt account for .25" lip on each side. This was a given. Are FHawks the only wheel that acounts for the lip too? .....or are the new GTAs actually 8.5" +.5" for lip? Ive just never seen it written that way.5
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Re: Firehawk offset vs. 17" GTA/crosslace offset
9.5" is the mounting width, the actual width is more in the 10.5" range. What is stamped on wheels is the measurement that the DOT approves and has to follow certain rules. Most wheels (from outside of flange to the other flange are in the 1" larger than stamped range - although some truck wheels can be closer to 2".
Ronals have the BS they do to make the Brembo kit (optional on the Firehawk) fit flush up front - using stock brakes and even some aftermarket you need the spacers.
The 17" GTA wheels are not meant to fit 3rd gens - they are more of a "universal fit" - they fit 2nd gens, late g-bodies and many other GM cars. 9" is narrow - but some of those cars cannot fit a 9.5", so they chose 9".
When one says 0mm - it means nothing, just that the wheel mounting flange is exactly in the middle of the wheel barrel. When you say 5.25" BS on a 9.5" wheel (which also happens to be 0mm), it tells you a lot more.
Ronals have the BS they do to make the Brembo kit (optional on the Firehawk) fit flush up front - using stock brakes and even some aftermarket you need the spacers.
The 17" GTA wheels are not meant to fit 3rd gens - they are more of a "universal fit" - they fit 2nd gens, late g-bodies and many other GM cars. 9" is narrow - but some of those cars cannot fit a 9.5", so they chose 9".
When one says 0mm - it means nothing, just that the wheel mounting flange is exactly in the middle of the wheel barrel. When you say 5.25" BS on a 9.5" wheel (which also happens to be 0mm), it tells you a lot more.
#13
Re: Firehawk offset vs. 17" GTA/crosslace offset
9.5" is the mounting width, the actual width is more in the 10.5" range. What is stamped on wheels is the measurement that the DOT approves and has to follow certain rules. Most wheels (from outside of flange to the other flange are in the 1" larger than stamped range - although some truck wheels can be closer to 2".
Ronals have the BS they do to make the Brembo kit (optional on the Firehawk) fit flush up front - using stock brakes and even some aftermarket you need the spacers.
The 17" GTA wheels are not meant to fit 3rd gens - they are more of a "universal fit" - they fit 2nd gens, late g-bodies and many other GM cars. 9" is narrow - but some of those cars cannot fit a 9.5", so they chose 9".
When one says 0mm - it means nothing, just that the wheel mounting flange is exactly in the middle of the wheel barrel. When you say 5.25" BS on a 9.5" wheel (which also happens to be 0mm), it tells you a lot more.
Ronals have the BS they do to make the Brembo kit (optional on the Firehawk) fit flush up front - using stock brakes and even some aftermarket you need the spacers.
The 17" GTA wheels are not meant to fit 3rd gens - they are more of a "universal fit" - they fit 2nd gens, late g-bodies and many other GM cars. 9" is narrow - but some of those cars cannot fit a 9.5", so they chose 9".
When one says 0mm - it means nothing, just that the wheel mounting flange is exactly in the middle of the wheel barrel. When you say 5.25" BS on a 9.5" wheel (which also happens to be 0mm), it tells you a lot more.
#14
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Re: Firehawk offset vs. 17" GTA/crosslace offset
9.5" is the mounting width, the actual width is more in the 10.5" range. What is stamped on wheels is the measurement that the DOT approves and has to follow certain rules. Most wheels (from outside of flange to the other flange are in the 1" larger than stamped range - although some truck wheels can be closer to 2".
Ronals have the BS they do to make the Brembo kit (optional on the Firehawk) fit flush up front - using stock brakes and even some aftermarket you need the spacers.
The 17" GTA wheels are not meant to fit 3rd gens - they are more of a "universal fit" - they fit 2nd gens, late g-bodies and many other GM cars. 9" is narrow - but some of those cars cannot fit a 9.5", so they chose 9".
When one says 0mm - it means nothing, just that the wheel mounting flange is exactly in the middle of the wheel barrel. When you say 5.25" BS on a 9.5" wheel (which also happens to be 0mm), it tells you a lot more.
Ronals have the BS they do to make the Brembo kit (optional on the Firehawk) fit flush up front - using stock brakes and even some aftermarket you need the spacers.
The 17" GTA wheels are not meant to fit 3rd gens - they are more of a "universal fit" - they fit 2nd gens, late g-bodies and many other GM cars. 9" is narrow - but some of those cars cannot fit a 9.5", so they chose 9".
When one says 0mm - it means nothing, just that the wheel mounting flange is exactly in the middle of the wheel barrel. When you say 5.25" BS on a 9.5" wheel (which also happens to be 0mm), it tells you a lot more.
Your hypothetical thick-lipped truck wheel with 5" back spacing and a thinner lipped steelie with 5" "backspacing" could have 5/8" difference in where the bead sits. That means the tire could be placed in vastly different places, and that's enough to make a wheel that should fit be a no-go.
0mm offset means the wheel mounting face is in the middle of the bead surfaces, if the wheel is properly made. A decorative outside lip differing in thickness from a functional inner lip won't change that.
Now, there are advertised wheel backspacings listed for product, but a given offset wheel should put the tire in the same place as another wheel of the same offset, all else being equal. The backspacing measurement you subscribe to does not have that consistency.
And that, when people are of the mentality they have to use every last bit of space, is a problem.
As for bigger GTA wheels, 18s are the way to go and nearly available.
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Re: Firehawk offset vs. 17" GTA/crosslace offset
Your hypothetical thick-lipped truck wheel with 5" back spacing and a thinner lipped steelie with 5" "backspacing" could have 5/8" difference in where the bead sits. That means the tire could be placed in vastly different places, and that's enough to make a wheel that should fit be a no-go.
I hope those g-body wheels have the right pad height - Hawks dropped the ball by using stock pad height making even 4 piston calipers a clearance problem.
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Re: Firehawk offset vs. 17" GTA/crosslace offset
Ok, apparently, my memory is seriously slipping and in this case, I'm part of the wrong info on the interwebs.
I just measured my 1991 firehawk wheels. total width is 10 1/8th inches. Bead area is a bit larger than 9.5 inches.
Sorry for the wrong info earlier. I'm going to go on a wheel measuring spree for a refresher.
I just measured my 1991 firehawk wheels. total width is 10 1/8th inches. Bead area is a bit larger than 9.5 inches.
Sorry for the wrong info earlier. I'm going to go on a wheel measuring spree for a refresher.