15" vs. 17" wheels, that big a difference?
#21
Team Owner
Thread Starter
From another post on suspension and Wheels that I posted a while back:
I have a 78 L-82 4 speed car with the gymkhana sport suspension (67,000 miles) that I have owned for 34 years and I have tinkered with the suspension one part at a time over all those years to achieve the perfect balance of superb handling, steering response and a firm but not harsh ride. Not knowing if you have a base suspension (most likely since most did not have the sport suspension from the factory) or the sport suspension, below is what you need for truly sportscar handling with a great ride for your 78:
Front:
550 lbs front coil springs/1 inch lower than stock-$100
1 1/8 inch solid front sway bar (OEM Bar size)-$200
poly upper and lower control arm bushings-$50
Bilstein HD shocks-$150
Front Spreader Bar-$100
Custom blueprinted/rebuilt OEM steering box- GTR 1999-Gary Ramadei-$300
This modification will make your OEM box about as good as it gets with the OEM steering and very close to a borgeson.....not quite but close
Rear:
360 monospring-$300
Bilstein Sport shocks-$150
OEM Style Rear Sway bar (not the aftermarket type bars. I highly discourage NON OEM/GM style rear sway bars)-7/16 or 9/16 or 3/4 inch (I have this one replacing the stock 7/16 inch bar)-$200
Competition adjustable strut rods with heim joint ends-$200
Total Cost $1750
This suspension will get you a FAR SUPERIOR suspension than what came on the car when it was new, X3 if the car had a base suspension from the factory. You will need to add 17/18 inch rims and tires (ZR rated only W/Y sub rating) later to maximize the superior suspension setup. I have ultra high performance summer only tires Front-255/45/17 ZR and rears 255/50/17 ZR's.
This is ^^^the basic C3 suspension design pretty much unmodified from its original design but maximized for handling, steering, response and grip....I will say this again, the ride is far superior to the OEM gymkhana suspension that came on the car with 255/60/15 crap tires and is very compliant. A neighbor who has lexus LsS460/430 sedans recently rode in my 78 and he commented more than once about the power is great BUT he could not believe how well and tight the ride was....kept saying it.
BTW-the SLP rims and tires above weigh LESS than the OEM aluminum 15 inch rims and 255/60/15 tires..I weighted them both.......................just saying
I have a 78 L-82 4 speed car with the gymkhana sport suspension (67,000 miles) that I have owned for 34 years and I have tinkered with the suspension one part at a time over all those years to achieve the perfect balance of superb handling, steering response and a firm but not harsh ride. Not knowing if you have a base suspension (most likely since most did not have the sport suspension from the factory) or the sport suspension, below is what you need for truly sportscar handling with a great ride for your 78:
Front:
550 lbs front coil springs/1 inch lower than stock-$100
1 1/8 inch solid front sway bar (OEM Bar size)-$200
poly upper and lower control arm bushings-$50
Bilstein HD shocks-$150
Front Spreader Bar-$100
Custom blueprinted/rebuilt OEM steering box- GTR 1999-Gary Ramadei-$300
This modification will make your OEM box about as good as it gets with the OEM steering and very close to a borgeson.....not quite but close
Rear:
360 monospring-$300
Bilstein Sport shocks-$150
OEM Style Rear Sway bar (not the aftermarket type bars. I highly discourage NON OEM/GM style rear sway bars)-7/16 or 9/16 or 3/4 inch (I have this one replacing the stock 7/16 inch bar)-$200
Competition adjustable strut rods with heim joint ends-$200
Total Cost $1750
This suspension will get you a FAR SUPERIOR suspension than what came on the car when it was new, X3 if the car had a base suspension from the factory. You will need to add 17/18 inch rims and tires (ZR rated only W/Y sub rating) later to maximize the superior suspension setup. I have ultra high performance summer only tires Front-255/45/17 ZR and rears 255/50/17 ZR's.
This is ^^^the basic C3 suspension design pretty much unmodified from its original design but maximized for handling, steering, response and grip....I will say this again, the ride is far superior to the OEM gymkhana suspension that came on the car with 255/60/15 crap tires and is very compliant. A neighbor who has lexus LsS460/430 sedans recently rode in my 78 and he commented more than once about the power is great BUT he could not believe how well and tight the ride was....kept saying it.
BTW-the SLP rims and tires above weigh LESS than the OEM aluminum 15 inch rims and 255/60/15 tires..I weighted them both.......................just saying
#22
Le Mans Master
Even in a 17" tire that is the same diameter (27") as my 15s there are not many choices. 255/50R17 is the same and 245/50R17 is 26.6". Very few choices and I really don't want to go to 18".
One of the choices is Nitto. Anybody have anything good or bad to say about them?
I'm thinking the NT 555 G2.
http://www.nittotire.com/find-a-tire...ameter=17#size
One of the choices is Nitto. Anybody have anything good or bad to say about them?
I'm thinking the NT 555 G2.
http://www.nittotire.com/find-a-tire...ameter=17#size
Actually quite a few available in 255/50/17:
https://www.discounttiredirect.com/f...width=255&cat=
https://www.tirerack.com/tires/TireS...earDiameter=17
I have the Kuhmo Ecsta SPT.....may not be available any longer though but some pretty good other choices^^^^^^^^^^^
Last edited by jb78L-82; 10-25-2017 at 05:29 PM.
#23
Pro
Even in a 17" tire that is the same diameter (27") as my 15s there are not many choices. 255/50R17 is the same and 245/50R17 is 26.6". Very few choices and I really don't want to go to 18".
One of the choices is Nitto. Anybody have anything good or bad to say about them?
I'm thinking the NT 555 G2.
http://www.nittotire.com/find-a-tire...ameter=17#size
One of the choices is Nitto. Anybody have anything good or bad to say about them?
I'm thinking the NT 555 G2.
http://www.nittotire.com/find-a-tire...ameter=17#size
#24
Le Mans Master
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I knew when I read the OP thread title that jb78L82 would be commenting as he has championed the performance improvements of better tires available than are available for the 15 inch rims. But, I will say again what I have said in the past,.....not everyone drives their C3 Corvette in ways that need performance tires. Hell,.....lots of people on this forum don't drive their cars at all. So, the original look of a 15 inch tire cannot be had with 17, and certainly not 18 inch wheels. For those that want an original look, all that super performance is irrelevant.
I would love it if I could drive my car with 17 inch tires and really see how much different it is. JB has offered to let me drive his car if I make it up his way, and maybe that will happen. What I will say is my aluminum 15 inch wheels with BFG TA tires seem to do very well in the curves of Pennsylvania...and I have pushed it. I am not yearning for any better performance, although being a American white male...we all love performance. If I were to switch to 17 or 18 rims, the only ones I would want on my car are the Torq Thrust wheels, and most of them still look like they have rubber bands for tires. Many many wheels I see on Corvettes on this forum are just ugly...to me. Especially when they don't fully fill the wheel wells. Some of us just don't like the look of big wheels with low profile tires.
My advice to the OP is to decide what matters most....original look with adequate performance, or non original look with improved performance....if he plans to use it. As for safety, nobody is convincing me that 15 inch Goodrich Radial TA's are unsafe.
I would love it if I could drive my car with 17 inch tires and really see how much different it is. JB has offered to let me drive his car if I make it up his way, and maybe that will happen. What I will say is my aluminum 15 inch wheels with BFG TA tires seem to do very well in the curves of Pennsylvania...and I have pushed it. I am not yearning for any better performance, although being a American white male...we all love performance. If I were to switch to 17 or 18 rims, the only ones I would want on my car are the Torq Thrust wheels, and most of them still look like they have rubber bands for tires. Many many wheels I see on Corvettes on this forum are just ugly...to me. Especially when they don't fully fill the wheel wells. Some of us just don't like the look of big wheels with low profile tires.
My advice to the OP is to decide what matters most....original look with adequate performance, or non original look with improved performance....if he plans to use it. As for safety, nobody is convincing me that 15 inch Goodrich Radial TA's are unsafe.
Last edited by Torqued Off; 10-25-2017 at 06:19 PM.
#25
Team Owner
Long time ago in a land far away I put C4 17" wheels on my '72, moved the brake cable, and wheel adapters from VBP same wheel center line and so the suspension/bearings are happy enough.....
so in the rear it's 275/50/17 and front is 255/50/17.....on '89 vette wheels....
FAR superior handling, and if you can't note THAT right off the spot....sell the car....
but seriously, that should be accompanied by the rest of the upgrades....
springs, shocks, steering, brakes, for starters.....
so in the rear it's 275/50/17 and front is 255/50/17.....on '89 vette wheels....
FAR superior handling, and if you can't note THAT right off the spot....sell the car....
but seriously, that should be accompanied by the rest of the upgrades....
springs, shocks, steering, brakes, for starters.....
#26
Le Mans Master
I knew when I read the OP thread title that jb78L82 would be commenting as he has championed the performance improvements of better tires available than are available for the 15 inch rims. But, I will say again what I have said in the past,.....not everyone drives their C3 Corvette in ways that need performance tires. Hell,.....lots of people on this forum don't drive their cars at all. So, the original look of a 15 inch tire cannot be had with 17, and certainly not 18 inch wheels. For those that want an original look, all that super performance is irrelevant.
I would love it if I could drive my car with 17 inch tires and really see how much different it is. JB has offered to let me drive his car if I make it up his way, and maybe that will happen. What I will say is my aluminum 15 inch wheels with BFG TA tires seem to do very well in the curves of Pennsylvania...and I have pushed it. I am not yearning for any better performance, although being a American white male...we all love performance. If I were to switch to 17 or 18 rims, the only ones I would want on my car are the Torq Thrust wheels, and most of them still look like they have rubber bands for tires. Many many wheels I see on Corvettes on this forum are just ugly...to me. Especially when they don't fully fill the wheel wells. Some of us just don't like the look of big wheels with low profile tires.
My advice to the OP is to decide what matters most....original look with adequate performance, or non original look with improved performance....if he plans to use it. As for safety, nobody is convincing me that 15 inch Goodrich Radial TA's are unsafe.
I would love it if I could drive my car with 17 inch tires and really see how much different it is. JB has offered to let me drive his car if I make it up his way, and maybe that will happen. What I will say is my aluminum 15 inch wheels with BFG TA tires seem to do very well in the curves of Pennsylvania...and I have pushed it. I am not yearning for any better performance, although being a American white male...we all love performance. If I were to switch to 17 or 18 rims, the only ones I would want on my car are the Torq Thrust wheels, and most of them still look like they have rubber bands for tires. Many many wheels I see on Corvettes on this forum are just ugly...to me. Especially when they don't fully fill the wheel wells. Some of us just don't like the look of big wheels with low profile tires.
My advice to the OP is to decide what matters most....original look with adequate performance, or non original look with improved performance....if he plans to use it. As for safety, nobody is convincing me that 15 inch Goodrich Radial TA's are unsafe.
But I will say that the 17's on my car with a MUCH better ride than the BFG TA's alone was worth the price of admission to me
Last edited by jb78L-82; 10-25-2017 at 07:05 PM.
#27
Had a 1976 L-82, 4-sp
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Royal Canadian Navy
A 27" diameter tire on a 15" is still a 27" diameter tire on a 17" or an 18" wheel. The wheel well is still filled but you just have a bit more wheel to admire.
#28
After reading are the posts, it looks like the 17" wheels are just the beginning of the required upgrades for some who posted.
So is it really about just changing the look to find better tires or is it all about throwing your vette around corners at the same performance level as a new vette?
I am just glad I still have great tread left on my Firestone's so I don't have to face that decision.
#29
Team Owner
Thread Starter
I knew when I read the OP thread title that jb78L82 would be commenting as he has championed the performance improvements of better tires available than are available for the 15 inch rims. But, I will say again what I have said in the past,.....not everyone drives their C3 Corvette in ways that need performance tires. Hell,.....lots of people on this forum don't drive their cars at all. So, the original look of a 15 inch tire cannot be had with 17, and certainly not 18 inch wheels. For those that want an original look, all that super performance is irrelevant.
I would love it if I could drive my car with 17 inch tires and really see how much different it is. JB has offered to let me drive his car if I make it up his way, and maybe that will happen. What I will say is my aluminum 15 inch wheels with BFG TA tires seem to do very well in the curves of Pennsylvania...and I have pushed it. I am not yearning for any better performance, although being a American white male...we all love performance. If I were to switch to 17 or 18 rims, the only ones I would want on my car are the Torq Thrust wheels, and most of them still look like they have rubber bands for tires. Many many wheels I see on Corvettes on this forum are just ugly...to me. Especially when they don't fully fill the wheel wells. Some of us just don't like the look of big wheels with low profile tires.
My advice to the OP is to decide what matters most....original look with adequate performance, or non original look with improved performance....if he plans to use it. As for safety, nobody is convincing me that 15 inch Goodrich Radial TA's are unsafe.
I would love it if I could drive my car with 17 inch tires and really see how much different it is. JB has offered to let me drive his car if I make it up his way, and maybe that will happen. What I will say is my aluminum 15 inch wheels with BFG TA tires seem to do very well in the curves of Pennsylvania...and I have pushed it. I am not yearning for any better performance, although being a American white male...we all love performance. If I were to switch to 17 or 18 rims, the only ones I would want on my car are the Torq Thrust wheels, and most of them still look like they have rubber bands for tires. Many many wheels I see on Corvettes on this forum are just ugly...to me. Especially when they don't fully fill the wheel wells. Some of us just don't like the look of big wheels with low profile tires.
My advice to the OP is to decide what matters most....original look with adequate performance, or non original look with improved performance....if he plans to use it. As for safety, nobody is convincing me that 15 inch Goodrich Radial TA's are unsafe.
Yes, 27"/15" is still a 27"/17" - but what I see is you really have to like that look to change out the original wheels.
After reading are the posts, it looks like the 17" wheels are just the beginning of the required upgrades for some who posted.
So is it really about just changing the look to find better tires or is it all about throwing your vette around corners at the same performance level as a new vette?
I am just glad I still have great tread left on my Firestone's so I don't have to face that decision.
After reading are the posts, it looks like the 17" wheels are just the beginning of the required upgrades for some who posted.
So is it really about just changing the look to find better tires or is it all about throwing your vette around corners at the same performance level as a new vette?
I am just glad I still have great tread left on my Firestone's so I don't have to face that decision.
#30
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I did post that high performance tires will be safer. This is a fact, not a subjective opinion. If they stick better and allow better vehicle control they they will be safer to drive on.
BTW, my 65 Impala is a ragtop cruiser. Certainly not a car I race around corner carving with. But, I still wouldn't go back to 15's on it.
#31
Who said they were unsafe????
I did post that high performance tires will be safer. This is a fact, not a subjective opinion. If they stick better and allow better vehicle control they they will be safer to drive on.
BTW, my 65 Impala is a ragtop cruiser. Certainly not a car I race around corner carving with. But, I still wouldn't go back to 15's on it.
I did post that high performance tires will be safer. This is a fact, not a subjective opinion. If they stick better and allow better vehicle control they they will be safer to drive on.
BTW, my 65 Impala is a ragtop cruiser. Certainly not a car I race around corner carving with. But, I still wouldn't go back to 15's on it.
#32
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In a panic situation, you WILL reach the limits of a BFG before you reach the limits of a better lower profile high performance tire. PERIOD.
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#33
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x2 they arent unsafe, just better for hard cornering..Like real hard
If you arent into autocrossing or higher speed track stuff you really dont need them. At a point "look" and personal tastes plays in there, too.
I
Came very close to getting 17s after finding a 315/35/17 tucked up under the EL....looked like a steamroller but spending 4k on wheels and tires..which I really wasnt crazy about. Nah
Plus with no sidewall they would just go up in smoke thats for kids.
If you arent into autocrossing or higher speed track stuff you really dont need them. At a point "look" and personal tastes plays in there, too.
I
Came very close to getting 17s after finding a 315/35/17 tucked up under the EL....looked like a steamroller but spending 4k on wheels and tires..which I really wasnt crazy about. Nah
Plus with no sidewall they would just go up in smoke thats for kids.
Last edited by cv67; 10-25-2017 at 11:02 PM.
#34
Melting Slicks
Sure are a lot of butt dynos saying 17s are absolutely the way to go...
More than likely they all had worn tires/not as good if tires as they had put on and thus th butt dyno results.
You can get performance tires in any size and doubt unless you road course it and need stiffer sidewalls you'd ever really notice a difference except for the looks.
More than likely they all had worn tires/not as good if tires as they had put on and thus th butt dyno results.
You can get performance tires in any size and doubt unless you road course it and need stiffer sidewalls you'd ever really notice a difference except for the looks.
Braking, Right & Left Loads are in g's.
http://www.jegs.com/i/Year-One-Wheel...78DKT/10002/-1
Also, if you use modern summer only tires, you will improve braking. In a panic stop, one of the biggest improvement you can make is tires.
#35
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I was never impressed with the wheels and BFG's I had on my car. It's hard to describe but it just never felt smooth. The tires were getting old so after looking at BFG prices I decided I wasn't spending that much on them again. It was under $400 more for the complete new setup compared to 4 new BFG's that I didn't really want. I like the new wheels better so it was an easy decision. And the new combo does work better.
I didn't write anything more about safety than the quick comment because it's usually more of a secondary consideration. After all, if anyone was that scared that all vehicle decisions put safety first then they'd be driving a top safety ranked new vehicle and would never drive an older car anywhere.
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silver74vette (10-27-2017)
#37
hmmm. I went and looked. They do make 18" x 8 REV classic 107s. Backspace is 4.5" so I'm wondering if that would be an issue.
While I was there I submitted a question asking if the standard center caps for 68-82 Corvettes would fit the wheel.
hmmmm.....
While I was there I submitted a question asking if the standard center caps for 68-82 Corvettes would fit the wheel.
hmmmm.....
#38
Race Director
I really wanted to stay with the 15" and rally wheels. With my brake upgrades the tolerances were too close between the rim and the calipers so I went with 17" and a period correct classic style wheel. With the right tires mounted they will be close to the look of the 15". A 27" diameter tire is still a 27" tire and with my suspension upgrades the car will be lower and the tires will nicely fill the wheel wells. I'm not a fan of 18" wheels because as stated above, they look to modern for a classic. It's a tough choice, but it's your car, do with it what you want.
#39
Melting Slicks
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I went from 15 to 17" because I like they way they look. I didn't notice much handling difference. But I did notice ride comfort. The 15" was definitely a softer ride and you didn't hear as much rattling in the car going over bumpy roads. But I sacrificed ride comfort for style.
#40
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I got Firestone indy 500 235/55/17 summer high performance tires from tire rack at just over $100 each. The previous winter I bought 4 bfg radial ta 235/60/15 for $165 apiece. The 17s are much nicer, cheaper and handle great
Last edited by Rescue Rogers; 10-26-2017 at 08:44 AM.