How much does 305 front tires rub????
01-22-2009, 09:19 PM
#1
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How much does 305 front tires rub????
When I got the "black widow" it had 305/35-18 tires mounted on 18x10" rims with 9" backspacing (nearly 89mm offset)....it rubbed REALLY bad....the new 295/30-18 tires fit great and don't rub until right at full lock...which is reduced by my double rack stops.....so heres the pics....
01-23-2009, 12:25 AM
#2
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So that's a difference of 10mm total in width, 5mm on the inside, a little less than 1/4" of diffference in inner interference. I've seen bigger differences between tire brands in the same tire sizes. Did you change brands as part of the size change? just curious...
01-23-2009, 01:38 AM
#3
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a couple of things here. 275s make this rub, and thats with 8" backspacing on a 9.5"rim. what you saw here could have been cause by your spin. whenever you spin and go extreme with the sterring, this kind of rubbing happens. See, I have some of it too. again, with less wheel inside the wheel wells.
Oh, now I know what you are talking about. that insulation is super light weight. I went on a bindge to remove it from the bottom of the car, and it not only takes FOREVER, it weighs almost NOTHING!!
Here is the pic of the wear marks . the real bad thing about a lot of rim inside the wheel well, is the rim touching the swaybar, if you have an adjustable swaybar. it acts like a lathe on the wheel edge.
My other set of rims are 8.5" backspacing for the 10" width.
Just have to be careful!
mk
mk
Oh, now I know what you are talking about. that insulation is super light weight. I went on a bindge to remove it from the bottom of the car, and it not only takes FOREVER, it weighs almost NOTHING!!
Here is the pic of the wear marks . the real bad thing about a lot of rim inside the wheel well, is the rim touching the swaybar, if you have an adjustable swaybar. it acts like a lathe on the wheel edge.
My other set of rims are 8.5" backspacing for the 10" width.
Just have to be careful!
mk
mk
01-23-2009, 04:03 AM
#5
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Brian, you can take it to a steam cleaner, like http://www.sanjoseautosteamcleaning.com/ and they willbe able to remove it pretty quickly and effectively. You might pay $100 to remove 20-30 lbs, over the whole underside. Maybe more if there is any crud build-up. relatively cheap weight loss, actually. 
Other things you can do to reduce weight that haven't been mentioned, go to a simple relay for the fans and lose the control boxes, reduce the hatch to just a skin with dzus fasteners or pins holding it on, go to hypercoils, remove fender liners.
Other things you can do to reduce weight that haven't been mentioned, go to a simple relay for the fans and lose the control boxes, reduce the hatch to just a skin with dzus fasteners or pins holding it on, go to hypercoils, remove fender liners.
01-23-2009, 01:09 PM
#6
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I had stripped an entire pile of that "crud" an it was less than a few oz! I would be willing to guess that that insulation is probably only 5lbs for the entire car. Dont even give that stuff a second thought.
01-23-2009, 02:00 PM
#7
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Mark, that stuff fluffs up when you scrape it off, and if you scrape it off a small area it won't seem like much. The answer to Brian's question is "Yes". As to the question of "how much weight", nobody knows till someone has done it. 
Also, there may be other built-up grease, dirt, etc stuck to the underside of the car. Obviously it would take forever t get it off with a putty knife, but a steam cleaner could probably strip it in 1/2 hour. Agreed this is probably well beyond the point of diminishing returns, but OTOH it all adds up.
Also, there may be other built-up grease, dirt, etc stuck to the underside of the car. Obviously it would take forever t get it off with a putty knife, but a steam cleaner could probably strip it in 1/2 hour. Agreed this is probably well beyond the point of diminishing returns, but OTOH it all adds up.
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01-23-2009, 02:20 PM
#8
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I did the side of one full frame rail and it took forever! this stuff will not come off that easily. anway, I weighed a big pile of it and figured out how much is left under the body, and worked it out to less than a couple of lbs. where did you get the calculation of 20 30 lbs? no way, all the lead reinforced rubber insulation in the interior was only 70lbs and there was a LOT of it!
again, the only way you are going to get the car in a different kind of weight class, is to do something RADICALLY to the chassis so you can get it under 2200lbs. THEN, that would be reallly something. Look at all the work anderson did. He did it to lower the weigth just a little (under 100lbs) but was able to add bars to the chassis to help with handling and strength. 50 to 60lbs is not going to do anything. Heck, ive had 50% of my fastest laps on the 2nd lap with 50 more lbs of gas in the tank. Im not saying weight is not a big deal, but there is a range that the car works well in and you cant get really beyond it unless you REALLY spend some money!
mk
again, the only way you are going to get the car in a different kind of weight class, is to do something RADICALLY to the chassis so you can get it under 2200lbs. THEN, that would be reallly something. Look at all the work anderson did. He did it to lower the weigth just a little (under 100lbs) but was able to add bars to the chassis to help with handling and strength. 50 to 60lbs is not going to do anything. Heck, ive had 50% of my fastest laps on the 2nd lap with 50 more lbs of gas in the tank. Im not saying weight is not a big deal, but there is a range that the car works well in and you cant get really beyond it unless you REALLY spend some money!
mk
Mark, that stuff fluffs up when you scrape it off, and if you scrape it off a small area it won't seem like much. The answer to Brian's question is "Yes". As to the question of "how much weight", nobody knows till someone has done it. Also, there may be other built-up grease, dirt, etc stuck to the underside of the car. Obviously it would take forever t get it off with a putty knife, but a steam cleaner could probably strip it in 1/2 hour. Agreed this is probably well beyond the point of diminishing returns, but OTOH it all adds up.
Also, there may be other built-up grease, dirt, etc stuck to the underside of the car. Obviously it would take forever t get it off with a putty knife, but a steam cleaner could probably strip it in 1/2 hour. Agreed this is probably well beyond the point of diminishing returns, but OTOH it all adds up.
01-23-2009, 02:37 PM
#9
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Who says I calculated? It was a guess. And it WILL come off easily using the method I described. Might take a little paint too, but that can be fixed with a rattle can if desired. Also the bits of road gravel & such that build up add up too -- unless that has all been cleaned away already.
Again, I'm not trying to say it's a brilliant idea, I was just answering Brian's question.
Again, I'm not trying to say it's a brilliant idea, I was just answering Brian's question.
01-23-2009, 02:45 PM
#10
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R888 295/30-10 is 11.8" wide, 25.1" tall
.68"=17.272mm or 8.636mm per side. The increased diameter would also be a major factor.
Toss the POS Toyos, get some 285 or 295 wide R6s and have tons more grip with no rubbing.
01-23-2009, 04:24 PM
#11
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After seeing exactly how much I paid for those R888's.....DAMM...they better last a while!
01-23-2009, 04:43 PM
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The hoosiers are not any faster for what brian will be doing this season. When my Vet competitor goes from toyos to hoosiers he is not any faster. He puts the new R6s on and I get a little nervous, but on the track, we are still with in tenths of a second between each other. the only diff being his HP (or was his HP advantage )
If he wants to see a huge different in grip, he should shave them! full tread is no where near the grip as the shaved tires.
The rubbing is due to driver error. if he doesnt go full lock, there will be no rubbing. as I showed, I have .5 less backspacing and still rub occasionally running 275 tires!!! even that is a big tire and WILL rub with if the tire fits under the fender well, and you know how tight my set up is.
the hight of the tires will give some fender hit, as im seeing with a 275 vs a 305 which is near 25" vs 26", so only .5 more radius. still, thats a lot.
The 295 is the right tire. Ill see if i can get a set of those at the WC GT race at Long Beach, as that is an option for the older vipers now!
Brian, I need to trade you the 335s for those 305s. How are they looking ? do they have much life? were those Anderson's throw aways?? Date code on the tire? (hopefully newer than '05)
mk
)If he wants to see a huge different in grip, he should shave them! full tread is no where near the grip as the shaved tires.
The rubbing is due to driver error. if he doesnt go full lock, there will be no rubbing. as I showed, I have .5 less backspacing and still rub occasionally running 275 tires!!! even that is a big tire and WILL rub with if the tire fits under the fender well, and you know how tight my set up is.
the hight of the tires will give some fender hit, as im seeing with a 275 vs a 305 which is near 25" vs 26", so only .5 more radius. still, thats a lot.
The 295 is the right tire. Ill see if i can get a set of those at the WC GT race at Long Beach, as that is an option for the older vipers now!
Brian, I need to trade you the 335s for those 305s. How are they looking ? do they have much life? were those Anderson's throw aways?? Date code on the tire? (hopefully newer than '05)
mk
01-23-2009, 05:17 PM
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I have the R888's now and REALLY like them.....granted my RA1's were used and towards the end of their life cycle... I really don't think the R888's in 295/30 rub much if at all...at least I can't hear it...even during lock over U turns?
After seeing exactly how much I paid for those R888's.....DAMM...they better last a while!
After seeing exactly how much I paid for those R888's.....DAMM...they better last a while!
The little POS Toyos for my CMC car are ~$220 each. 
Mark, it's not fractions of a second... it's seconds difference. The Mid-Atlantic class champion CMC car and driver has the track record on SPR and VIR. New, shaved, properly heat-cycled RA-1s vs free, used, several heat cycle old R6s... 2 seconds on Summit Point Main. A few E36 drivers have told me 3-4 seconds at VIR.
Yes, Brian would gain from running Hoosiers. He would learn better car control due to the release characteristics as the tires lose adhesion. Also, if he's buying new tires Hoosiers cost $30-50 less than Toyos in wide 18" sizes.
01-23-2009, 06:15 PM
#14
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That is very debatable. Trust me, I would love to think that i could run 4 seconds faster on a hoosier R6, but thats not reality. there are many series where times are all over the map. we get to Laguna more often as a home track than most any group or series at any track, and I see all the top teams here with all sorts of equip. the BMW e36 guys, (who by the way, a lot of them are out here and make it back there for those races) are not seeing those kind of time differences. Bruce matesso, for example, runs a hot e36 Dmod car out here and we also run neck and neck and have for many years. He saw style differences in drving the hoosiers vs toyos, but not seconds. I also, see the same thing. (not to mention the Vet driver, Rob Wardlow, the vipers, etc etc) . what you are saying is that hoosiers are as fast as slicks which are about 2 seconds faster than toyos. Look at anderson as well. he just ran on some toyos and switched to new, expensive slicks! 2 seconds.
when guys say 2-3 seconds, i have to laugh. the only tire that is proven to be 3-4 seconds slower is when you go from a Street tire 280 tread wear to a real DOT slick. otherwise, even the TOP magazines are doing the tests, and they are seeing 1 second difference between certain types of tires in the DOT world, hoosier, not even being the best. Plus, we have seen even better results on the A series of the R6s (A6s, for autocross, but used in Road racing)
they come up to temp faster and have more stick. I might even say that they could be a second faster still, but thats a guess.
Bottom line, Ive driven both and have my fastest time at Laguna before any track change, to be 1:40.2 with toyos and hoosiers (relatively new). with the track change that time went down to 1:38.8 but the car is better. now with the new motor, 1:37.7 and should be near 1:37.0 this year. However, a set of hoosiers will not bring this time down to 1:35!
WC GT runs toyo RA1s and watch the times a track near you with all sorts of different equip. touring or GT. these cars ARE NOT 2 -3 seconds faster on hoosiers. However, they might be 2 seconds faster on a real ALMS slick! by the way, there was a cup car driven by henzler that ran in the supercup challenge at a particular track. it ran 1 second slower on the Toyos vs the michelin slicks. (his WCGT car was broke, so they used the supercup racer with toyos) .
Ill finish with this. There are many folks that cannot drive the toyos because they are a little different to drive than the Hoosiers. They need to be slid and this is how they are fast. if you drive them like hoosiers, they might be slower.
I dont think one vs the other is that big of a difference. my racer comrades Rob in the C5 vet ran a new set of hoosiers last year, and so did Bruce in the M3. these are two very good , top timed drivers that know Laguna seca. they saw little if any difference. And when i saw them put the tires on before the race, i was not worried, as ive driven both!
my stroker motor is only worth 1 to 2 seconds a lap and thats 60-65hp!!!
btw. even though hoosiers are cheaper as you say, they heat cycle out much faster as you must know. the end result, brian has the right tires for what he is doing. If I was to advise him, it would have been to get them shaved.
mk
when guys say 2-3 seconds, i have to laugh. the only tire that is proven to be 3-4 seconds slower is when you go from a Street tire 280 tread wear to a real DOT slick. otherwise, even the TOP magazines are doing the tests, and they are seeing 1 second difference between certain types of tires in the DOT world, hoosier, not even being the best. Plus, we have seen even better results on the A series of the R6s (A6s, for autocross, but used in Road racing)
they come up to temp faster and have more stick. I might even say that they could be a second faster still, but thats a guess.
Bottom line, Ive driven both and have my fastest time at Laguna before any track change, to be 1:40.2 with toyos and hoosiers (relatively new). with the track change that time went down to 1:38.8 but the car is better. now with the new motor, 1:37.7 and should be near 1:37.0 this year. However, a set of hoosiers will not bring this time down to 1:35!
WC GT runs toyo RA1s and watch the times a track near you with all sorts of different equip. touring or GT. these cars ARE NOT 2 -3 seconds faster on hoosiers. However, they might be 2 seconds faster on a real ALMS slick! by the way, there was a cup car driven by henzler that ran in the supercup challenge at a particular track. it ran 1 second slower on the Toyos vs the michelin slicks. (his WCGT car was broke, so they used the supercup racer with toyos) .
Ill finish with this. There are many folks that cannot drive the toyos because they are a little different to drive than the Hoosiers. They need to be slid and this is how they are fast. if you drive them like hoosiers, they might be slower.
I dont think one vs the other is that big of a difference. my racer comrades Rob in the C5 vet ran a new set of hoosiers last year, and so did Bruce in the M3. these are two very good , top timed drivers that know Laguna seca. they saw little if any difference. And when i saw them put the tires on before the race, i was not worried, as ive driven both!
my stroker motor is only worth 1 to 2 seconds a lap and thats 60-65hp!!!
btw. even though hoosiers are cheaper as you say, they heat cycle out much faster as you must know. the end result, brian has the right tires for what he is doing. If I was to advise him, it would have been to get them shaved.
mk
I pay $40 each (upped to $50 this year) for my 285/30-18 R6s. The little POS Toyos for my CMC car are ~$220 each.
Mark, it's not fractions of a second... it's seconds difference. The Mid-Atlantic class champion CMC car and driver has the track record on SPR and VIR. New, shaved, properly heat-cycled RA-1s vs free, used, several heat cycle old R6s... 2 seconds on Summit Point Main. A few E36 drivers have told me 3-4 seconds at VIR.
Yes, Brian would gain from running Hoosiers. He would learn better car control due to the release characteristics as the tires lose adhesion. Also, if he's buying new tires Hoosiers cost $30-50 less than Toyos in wide 18" sizes.
The little POS Toyos for my CMC car are ~$220 each. Mark, it's not fractions of a second... it's seconds difference. The Mid-Atlantic class champion CMC car and driver has the track record on SPR and VIR. New, shaved, properly heat-cycled RA-1s vs free, used, several heat cycle old R6s... 2 seconds on Summit Point Main. A few E36 drivers have told me 3-4 seconds at VIR.
Yes, Brian would gain from running Hoosiers. He would learn better car control due to the release characteristics as the tires lose adhesion. Also, if he's buying new tires Hoosiers cost $30-50 less than Toyos in wide 18" sizes.
Last edited by mark kibort; 01-23-2009 at 06:41 PM.
01-23-2009, 06:58 PM
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The POC Laguna track records are as follows and that is with noise restrictive exhaust mods...just the faster classes. NP 1:42.141 369 JOHN KEANE 8/27/2006
V5 1:53.117 356 JOHN TUNNICLIFFE 8/22/2004
V4 1:43.207 42 BRUCE WELLS 8/24/2008
V3 1:37.181 3 STEVE ALARCON 8/26/2007 .
V2 1:39.226 131 KARY CLEMENTS 8/24/2008
V1 1:39.250 398 MARCEL BONT 8/24/2003
V0 1:35.045 17 MARTY MEHTERIAN 8/24/2008
GTA 1:29.678 204 BLAKE ROSSER 8/26/2007
GTC-3 1:33.437 919 DREW WATERHOUSE 8/26/2007
GTC-4
GT1 1:30.412 77 DOUG BARON 8/25/2002
GT2 1:32.845 144 JOHN PAYNE 8/24/2008
GT3 1:38.708 8 RANDY BECK 8/15/1999
GT4 1:36.985 372 NEIL ALEXANDER 8/24/2008
V5 1:53.117 356 JOHN TUNNICLIFFE 8/22/2004
V4 1:43.207 42 BRUCE WELLS 8/24/2008
V3 1:37.181 3 STEVE ALARCON 8/26/2007 .
V2 1:39.226 131 KARY CLEMENTS 8/24/2008
V1 1:39.250 398 MARCEL BONT 8/24/2003
V0 1:35.045 17 MARTY MEHTERIAN 8/24/2008
GTA 1:29.678 204 BLAKE ROSSER 8/26/2007
GTC-3 1:33.437 919 DREW WATERHOUSE 8/26/2007
GTC-4
GT1 1:30.412 77 DOUG BARON 8/25/2002
GT2 1:32.845 144 JOHN PAYNE 8/24/2008
GT3 1:38.708 8 RANDY BECK 8/15/1999
GT4 1:36.985 372 NEIL ALEXANDER 8/24/2008