[00vtecLude]

I know this has been talked about alot and ive read through the archives, but I hear all sorts of mixed info about what kind of tires I can/should be running with a 18x7.5 wheel w/ 45 offset. My car is lowered ~1.8 (1 finger gap all around) with prokits and konis, and I was wondering whats the best size. I would like to run a 40 series to give that extra little cushion to prevent damage to the wheel, etc. but Im pretty sure these wont fit. And what is this stuff about sidewall guards and stuff to keep from hitting the wheel on potholes?

Any help would be greatly appreciated cuz im going to be getting these tires soon...

sorry bout the repeated post~

 

[00vtecLude]

ttt, anyone?

 

[eatsgti]

With 18s I think you should be running 35 series tires to minimize the difference in speedometer readings caused by the change in overall wheel size. This is going to be hard on your rims though if you have a lot of ruts around. Someone with 18s can help you more... for my 17 inchers I run 215 x 40 and they fit fine and the ride is good.

Some tires have a little overlap or bulge on th outside edge that helps to protect the lip of the rim... granted, nothing will protect your rim if you drive right up alongside a curb.

For potholes you basically have no protection but the stiffness of the side wall.

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Yum, VW GTIs for breakfast lunch and dinner...

[This message has been edited by eatsgti (edited April 17, 2001).]

 

[00vtecLude]

ok.. so 35 it is. But can I fit 225 or do I have to go 215? or am i going to have to put the springs on a higher perch setting to prevent rubbing, etc?

 

[smoothludey]

If you haven't bought the 18 inch rims yet, don't buy them, or if you have already try to exchange them for 17s. The 18s are great looking, but they are really not worth it when it comes to performance. I have 18x7.5 rims running 225/35/18 S02s. two of the rims are already bent and on top of that the setup is slightly larger than stock, which is really killing my acceleration noticeably. I recently went back to the stocks and my car was flying like a bird. The new rims i have are also lighter, but the stocks for some reason pulled harder and i can only attribute that to the size increase. Ok, now you want 18s and you want to prevent any dents in your rims...with a 40 series tire that might be possible, but that size is even bigger than my 225/35/18 setup which will really kill your performance. My setup not only kills the rims, but it also gives you mega vibrations throughout the car, and with your drop it would only be magnified. It's up to you, what you want out of your rims...if it were up to me to do it all over again I'd go with 17s and a 215/40/17 tire, which is exactly stock spec.

 

[aklucsarits]

<font face="Verdana, Arial" size="2">Originally posted by smoothludey:
If you haven't bought the 18 inch rims yet, don't buy them, or if you have already try to exchange them for 17s. The 18s are great looking, but they are really not worth it when it comes to performance. I have 18x7.5 rims running 225/35/18 S02s. two of the rims are already bent and on top of that the setup is slightly larger than stock, which is really killing my acceleration noticeably. I recently went back to the stocks and my car was flying like a bird. The new rims i have are also lighter, but the stocks for some reason pulled harder and i can only attribute that to the size increase. Ok, now you want 18s and you want to prevent any dents in your rims...with a 40 series tire that might be possible, but that size is even bigger than my 225/35/18 setup which will really kill your performance. My setup not only kills the rims, but it also gives you mega vibrations throughout the car, and with your drop it would only be magnified. It's up to you, what you want out of your rims...if it were up to me to do it all over again I'd go with 17s and a 215/40/17 tire, which is exactly stock spec.</font>

A larger diameter wheel/tire combo is detrimemental to acceleration regardless of weight because it effectively lowers your final drive ratio. On the other hand, a larger diameter combo will actually give you a higher top speed. But how often do you get to test top speed...

The ideal wheel/tire +1 upgrade for a prelude would be a 215/40/17 tire which ends up being just about 1% under stock size.

Andrew

 

[00vtecLude]

yea.. but when getting the wheels I wasnt really concerned about performance since the SS tranny probably kills me more than anything. Im not out there trying to dragrace everyone I see, so I figured looks was probably the way to go.

smooth: do the 225's fit ok? or do you recommend the 215's?

 

[00vtecLude]

how many of you are running 225's?

 

[smoothludey]

<font face="Verdana, Arial" size="2">Originally posted by 00vtecLude:
yea.. but when getting the wheels I wasnt really concerned about performance since the SS tranny probably kills me more than anything. Im not out there trying to dragrace everyone I see, so I figured looks was probably the way to go.

smooth: do the 225's fit ok? or do you recommend the 215's?</font>

For 18x7.5 rims i would go with a 225/35/18 tire, which fit great by the way, and is a bit larger than stock specs but will give you sufficient rubber to somewhat protect the rims. Also, get at least a 48mm offset or higher cuz the rears tend to catch ther rear fenders even at stock height.

 

[schwett]

the diameter is one thing, but most of us are running combos that are fairly close to the original o.d.

what kills acceleration more is the MUCH higher moment of inertia of an 18" rim and the tire that sits on it. a 225/35 is going to be 10% heavier than the stock tire, and that weight is going to be farther from the axis of the rim which increases the moment of inertia at the SQUARE of that distance! to grossly, grossly oversimplify if you had a band of rubber that was 8" wide at 9" from the axis, it would have a moment of inertia about 40% larger than an 8" wide band of rubber at 8" from the axis. the same applies for your rims. if they're the same weight, but 18" they will be harder to rotate than the 16s. i figured it out one time, but i don't remember the exact numbers... to get the same performance out of 18x7.5s with a 225/35 tire (within .1" of the stock diameter) you'd need a 13lb rim and a an 18 lb tire or so!

<font face="Verdana, Arial" size="2">Originally posted by aklucsarits:
A larger diameter wheel/tire combo is detrimemental to acceleration regardless of weight because it effectively lowers your final drive ratio. On the other hand, a larger diameter combo will actually give you a higher top speed. But how often do you get to test top speed...

The ideal wheel/tire +1 upgrade for a prelude would be a 215/40/17 tire which ends up being just about 1% under stock size.

Andrew</font>

 

[SteveV]

my rims are 18x7.5 with 42mm offset and I run 215/40/18 tires. I'm lowered at least 2 inches and I only rub on very hard cornering and really large bumps in the road. And like everyone says, the 18s kill your performance, but no matter to me, because I'll all about show

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Steve
2000 Prelude SS
"Mugen Equipped"

 

[H22A VTEC]

18's are great but if you live near the city like I do (Washington DC), potholes are HORRIBLE to encounter and also, parallel parking can suck cuz you can sometimes hit the rim on the curb. 17's are just a LOT more practical BUT i'm keeping my 18's since they look nice as hell. BTW, i'm running on 215-35-18zr series tires with H&R and stock shocks. and my rims are 18x7?

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