Bigger tires
05-18-2003, 11:08 PM
#1
0.0 BAR
Thread Starter
Join Date: May 2003
Posts: 46
Bigger tires
I've been lurking for about 2 months. Read all the FAQs.
93 DelSolSi (D16z6)auto. Running 9 lbs of boost. Engine is being rebuilt right now.
Next upgrade will be to Tein adjustable shock/coil system.
My question is going from the stock 15" rims to 17". What will the offset be for the speedometer ? In other words, when the speedometer says 60 mph, approx. what will my real speed be ?
93 DelSolSi (D16z6)auto. Running 9 lbs of boost. Engine is being rebuilt right now.
Next upgrade will be to Tein adjustable shock/coil system.
My question is going from the stock 15" rims to 17". What will the offset be for the speedometer ? In other words, when the speedometer says 60 mph, approx. what will my real speed be ?
ie. if you run 205/40 r17 according to mine and the state patrol it about 5 over..drop down to a 35 series tire and it might be closer to the same 
05-19-2003, 10:09 PM
#3
0.0 BAR
Join Date: Dec 2002
Posts: 0
Re:Bigger tires
You have it backwards... The bigger the outer diameter of your tires are the slower your speedometer will say you are going.
Once you get your new tires just have somebody drive next to you doing the speed limit and they can tell ya how fast you were really going.
Once you get your new tires just have somebody drive next to you doing the speed limit and they can tell ya how fast you were really going.
05-20-2003, 08:27 AM
#4
3.0 BAR
Join Date: Feb 2003
Posts: 9,089
Re:Bigger tires
05-20-2003, 09:25 AM
#6
1.0 BAR
Join Date: Jan 2003
Posts: 586
Re:Bigger tires
one thing to remember though too..... even stock tires can change outer diameter by up to a 1/2 inch (or more depending on tread depth) as they wear down. so if you get it close to stock, it's going to be just fine.
05-20-2003, 10:59 AM
#8
1.0 BAR
Join Date: Jan 2003
Posts: 586
Re:Bigger tires
hhhm... can you cram a 205 on a 6.5" rim? 205mm is about 8 inches, that's about 3/4 over the rim. i'm looking at getting a set of 15x6.5 and wanted to get a set of 205/50's. i'm just not up to snuff on my tire sizing....
05-20-2003, 11:50 AM
#10
1.0 BAR
Join Date: Jan 2003
Posts: 586
Re:Bigger tires
actually, stock CRX wheels are 185/60-14. and i was looking at 205/50-15. the link above lists the difference as less than 1/2 diameter and onlt 1.5% speedometer difference (speedo at 60, i'll be traveling 60.9). with autocrossing a lot, i want to get as much rubber down as i can, that's why i was looking at 205.
