Does your Z do this on on-ramps?

[RCAnismo]

Lately I've been leaving my traction control on and I notice if I take long sweeping on-ramps with a large turning radius the light comes on and the traction control is engaged and cuts power to the wheels. I'm usually going at a decent pace around the bend but the tires are definitely not spinning. Is this normal or should I take it to the dealer to have it looked at?

[_b.jaye_]

i noticed the same thing on a gradual s-curved downhill stretch of highway.... only once, but i havent been on the road since. power seemed too shutter a bit... i thought it was cause i had the cruise set at first, but it did it without. be curious to here if anyones got an idea what the deal is

[dasoupdude]

lol who leaves that switch on nowadays

(not me because i have a base and only have two void button square cut outs. )

[Anthonysflying]

Nice wheels! What size tires are you running? Your TCS may be kicking in because of a larger than stock diameter. or you may have had the joy of dealing with this. The Nissan dealer i went to mount my tires on thought i had a front wheel drive car and put the larger tires on the front. Needless to say the TCS kicked in during turns all the time. Tires1010 (website) has a calculator you can use to compare stock sizes to new sizes. A diameter variance of 3% is enough to set off your TCS.

[xjmxstac]

Mine does it when i exit a 25 at 50. <50 no.

[rmezz13]

just turn that ish off, gas it a little extra on them turns and make it break a little, then shoot out.... much more fun. TC FTL

[RCAnismo]

Nice wheels! What size tires are you running? Your TCS may be kicking in because of a larger than stock diameter. or you may have had the joy of dealing with this. The Nissan dealer i went to mount my tires on thought i had a front wheel drive car and put the larger tires on the front. Needless to say the TCS kicked in during turns all the time. Tires1010 (website) has a calculator you can use to compare stock sizes to new sizes. A diameter variance of 3% is enough to set off your TCS.

Good point. I didn't really think about the size of the rims making a difference but I only went up an inch over stock, 19 inch, but the width is a lot wider than stock also, 8.5 in the front and 10.5 in the rear, probably has something to do with it.

just turn that ish off, gas it a little extra on them turns and make it break a little, then shoot out.... much more fun. TC FTL

Agreed. I'm gonna go back to leaving it off and not worry about it.

[redsx13]

The 350z has one of the worst tcs systems i have ever felt. It is not at all advanced , it is basically a failsafe that keeps the wheels from spinning. If works solely off of wheel speed sensors, ther are no other yaw or angle sensors.

the power cut is very abrupt, and engauges fairly easily.

"How big of a speed difference would you say it kicks in at?"around a 2/3 rotation of the rear wheel independently from the front.(depending on wheel size)

[redsx13]

Agreed. I'm gonna go back to leaving it off and not worry about it.

be careful, i dont mean to sound like a d!ck, but some helpful advice would be to learn how to drive with it on and when you get better and it starts to slow you down, switch it off. Public roads and freeways for that matter aren't the best place to feel out your car, if you slip up (like we all will do at some point) you could be in a whole mess of trouble.

In 2004 the 350z was ranked one of the most unsafe new cars in America, not because of its crash test ratings, but because of the number of them involved in fatal crashes. Although a study was never carried out, there is a good chance a number of these crashes where a direct result of the ability to disable traction control so easily.

Many car manufacturers have tcs fail-safes just for this reason. the failsafes imposed by many of the top manufacturers have limited the ability to disable the tcs systems 100%, thus limiting the amount of crashes resulting from an "out-of -control" car.

again, sorry to be a complete buzz-kill, but it is just something to consider.
Modified by redsx13 at 1:34 AM 1/8/2009

[RCAnismo]

Well, it's not that I'm takin these curves at break neck speeds or trying to drift around an on-ramp. I take my Jeep around these bends at a faster pace than when the traction control starts coming on in the Z. It's engaging waaaaaay to early. I'm no where near spinning out of control, that's why I thought it was really odd it was even coming on at all.

I wouldn't recommend testing your driving abillities on the street either, that would be fit for the track, but a car that wouldn't let you turn off the tcs would be gay. I'm glad car manufacturers haven't started doing that yet.

[Jacko3]

Learn to drive with the traction control or VDC OFF. its way more fun. I only use ot drive my G-35 Coupe ONLY when it rains. Other than that, the rest is steering control and braking. What type and size of tires are you using---that could also be a problem. I use TOYO Proxes T1R and I have 245X35X19 in front, and a 275X35X19 at the rear and I have never had this sort of problem, even with my tires going bald on the first set.

[RCAnismo]

Learn to drive with the traction control or VDC OFF. its way more fun. I only use ot drive my G-35 Coupe ONLY when it rains. Other than that, the rest is steering control and braking. What type and size of tires are you using---that could also be a problem. I use TOYO Proxes T1R and I have 245X35X19 in front, and a 275X35X19 at the rear and I have never had this sort of problem, even with my tires going bald on the first set.

. I'm running 19x8.5 +25 F and 19x10.5 +22R. Tires are 235/35/19 F and 275/30/19 R pretty close measurements to yours, I don't think my tcs should be kicking in.

[redsx13]

. I'm running 19x8.5 +25 F and 19x10.5 +22R. Tires are 235/35/19 F and 275/30/19 R , I don't think my tcs should be kicking in.

ya, that setup shouldn't cause any problems.

If you think you can get you tcs to kick in on a dealership testdrive, go ahead and bring it in, but i have done a lot of business with dealerships, and there is a good chance that service manager will laugh at you. and if they do find something wrong, they will more than likely bame it on your rims.

[Jacko3]

My wheels are factory 8.0 in the front and 8.5 at the rear.

[C-Kwik]

. I'm running 19x8.5 +25 F and 19x10.5 +22R. Tires are 235/35/19 F and 275/30/19 R pretty close measurements to yours, I don't think my tcs should be kicking in.

Your front tire turns about 817 Revolutions per mile while your rear tire size does about 814 Revs/Mile. Jacko's set up runs 807 and 783 Revs/Mile front and rear respectively. Your set up has a difference of only 3 Revs/mile vs Jacko's 24 Revs/Mile difference.

From another post I made for one of our mods:

The 17 inch G35 wheels came with tire sizes of 225/50/17 and 235/50/17 which have Revs/Mile of 803 and 791 respectively. The difference is 12 Revs/Mile.

Th 18 inch G35 and 350z wheels came with 225/45-18 and 245/45/18 which have Revs/Mile of 803 and 778 respectively. The difference is 25 Revs/Mile.

The 19" G35 wheels came with 225/40-19 and 245/40-19 which have Revs/Mile of 797 and 778 respectively. The difference is 19 Revs/Mile.

The 350Z GT wheels came with 245/40-18 and 265/35-19 which have Revs/Mile of 809 and 790 respectively. The difference is 19 Revs/Mile.

Based on this info, the range of difference in Revs/Mile that we know will work is 12-25.

As you can see, you are well outside of the OE's revs/mile difference range. From your description, I suspect that you may be right on the edge of what is acceptable in a straight line, but during certain turns (in which the computations woud likely be somewhat complex since all 4 wheels would register different speeds) it may stray out into values that the computer is programmed to consider as wheel slip.

[redsx13]

Your front tire turns about 817 Revolutions per mile while your rear tire size does about 814 Revs/Mile. Jacko's set up runs 807 and 783 Revs/Mile front and rear respectively. Your set up has a difference of only 3 Revs/mile vs Jacko's 24 Revs/Mile difference.

From another post I made for one of our mods:

The 17 inch G35 wheels came with tire sizes of 225/50/17 and 235/50/17 which have Revs/Mile of 803 and 791 respectively. The difference is 12 Revs/Mile.

Th 18 inch G35 and 350z wheels came with 225/45-18 and 245/45/18 which have Revs/Mile of 803 and 778 respectively. The difference is 25 Revs/Mile.

The 19" G35 wheels came with 225/40-19 and 245/40-19 which have Revs/Mile of 797 and 778 respectively. The difference is 19 Revs/Mile.

The 350Z GT wheels came with 245/40-18 and 265/35-19 which have Revs/Mile of 809 and 790 respectively. The difference is 19 Revs/Mile.

Based on this info, the range of difference in Revs/Mile that we know will work is 12-25.

As you can see, you are well outside of the OE's revs/mile difference range. From your description, I suspect that you may be right on the edge of what is acceptable in a straight line, but during certain turns (in which the computations woud likely be somewhat complex since all 4 wheels would register different speeds) it may stray out into values that the computer is programmed to consider as wheel slip.

very nice!, this is something people rarely consider when upgrading wheels and tires.

[ldstang50]

C-KwikGreat post.Do you think if the OP changed to a 245 front that would make a difference in his TCS kicking on?A 245/35/19 would turn 783r/mi while the 275/30/19 would be 791r/mi. That would be a more measurable difference between the two.Also does the computer for TCS base itself on difference in wheel speed between the front and rear or the difference in rear wheel speed from engine rpm?

[C-Kwik]

Do you think if the OP changed to a 245 front that would make a difference in his TCS kicking on?A 245/35/19 would turn 783r/mi while the 275/30/19 would be 791r/mi. That would be a more measurable difference between the two.Also does the computer for TCS base itself on difference in wheel speed between the front and rear or the difference in rear wheel speed from engine rpm?

I doubt it as a 245/35-19 would be larger than the 275/30-19. While it would create a bigger difference, it would be in the wrong direction. Basically I was subracting the rear tire's revs/mile from the front tire's revs/mile. If you did that with the revs/mile specs you listed, he'd be in the negative, which would be numerically lower than the set-up he has now. The most feasible change would be to increase the rear tire size to a 275/35-19. With such a wide tire, the 5 point difference in aspect ratio makes a much more dramatic change in diameter. About an inch, in fact. While the 245/35-19 is a step in the wrong direction, it also only represents about a .3" difference in diameter anyways. The only change that could be made to the front tire would be to either find a 30 series tire (not sure if anyone makes such a tire in a 235 width) or drop to a 225/35-19. But that represents a bigger width stagger which might not be ideal. Hell, I think a 235/275 stagger is already a bit much.

Additionally, it should be noted that my figures were primarily based on Michelin PS2 tires. Different tire models can have slightly different rev/mile counts even in the same size tires. Best to look up the specific tires that will be used. I'd also aim for a front to rear diameter ratio that is somewhat in the middle of the known range as uneven front to rear tire wear can change this ratio. Especially if you plan to only replace pairs of tires at a time. I generally replaced all 4 at one time in all cars that I ran staggerred set ups on. Needless to say, I always had a ton of back-up front tires available.

[RCAnismo]

Your front tire turns about 817 Revolutions per mile while your rear tire size does about 814 Revs/Mile. Jacko's set up runs 807 and 783 Revs/Mile front and rear respectively. Your set up has a difference of only 3 Revs/mile vs Jacko's 24 Revs/Mile difference.

From another post I made for one of our mods:

The 17 inch G35 wheels came with tire sizes of 225/50/17 and 235/50/17 which have Revs/Mile of 803 and 791 respectively. The difference is 12 Revs/Mile.

Th 18 inch G35 and 350z wheels came with 225/45-18 and 245/45/18 which have Revs/Mile of 803 and 778 respectively. The difference is 25 Revs/Mile.

The 19" G35 wheels came with 225/40-19 and 245/40-19 which have Revs/Mile of 797 and 778 respectively. The difference is 19 Revs/Mile.

The 350Z GT wheels came with 245/40-18 and 265/35-19 which have Revs/Mile of 809 and 790 respectively. The difference is 19 Revs/Mile.

Based on this info, the range of difference in Revs/Mile that we know will work is 12-25.

As you can see, you are well outside of the OE's revs/mile difference range. From your description, I suspect that you may be right on the edge of what is acceptable in a straight line, but during certain turns (in which the computations woud likely be somewhat complex since all 4 wheels would register different speeds) it may stray out into values that the computer is programmed to consider as wheel slip.

I doubt it as a 245/35-19 would be larger than the 275/30-19. While it would create a bigger difference, it would be in the wrong direction. Basically I was subracting the rear tire's revs/mile from the front tire's revs/mile. If you did that with the revs/mile specs you listed, he'd be in the negative, which would be numerically lower than the set-up he has now. The most feasible change would be to increase the rear tire size to a 275/35-19. With such a wide tire, the 5 point difference in aspect ratio makes a much more dramatic change in diameter. About an inch, in fact. While the 245/35-19 is a step in the wrong direction, it also only represents about a .3" difference in diameter anyways. The only change that could be made to the front tire would be to either find a 30 series tire (not sure if anyone makes such a tire in a 235 width) or drop to a 225/35-19. But that represents a bigger width stagger which might not be ideal. Hell, I think a 235/275 stagger is already a bit much.

Additionally, it should be noted that my figures were primarily based on Michelin PS2 tires. Different tire models can have slightly different rev/mile counts even in the same size tires. Best to look up the specific tires that will be used. I'd also aim for a front to rear diameter ratio that is somewhat in the middle of the known range as uneven front to rear tire wear can change this ratio. Especially if you plan to only replace pairs of tires at a time. I generally replaced all 4 at one time in all cars that I ran staggerred set ups on. Needless to say, I always had a ton of back-up front tires available.

Wow. Now that's good stuff.

[famousyellowz]

Isn't it easier to look at the difference in overall tire diameters than trying to figure out how many revs each tire makes per mile. Should be near 1" difference from rear to front.

As for the safety issue with on and off of TCS or VDC. I would rather have the ability to turn it of than not. How can one be expected to track a sports car if you can't disable the safety controls. This is perfect for autox and street classes.

[BlackSmoke]

C-Kwik laying the smack down, well written. Your job now is to teach Richie how to search and write good posts.

[R350Zz33]

haha ur funny and who's job is it to get you out of your mid life crisis. CHAD? who?

[Anthonysflying]

Whut....

[RCAnismo]

Dang, and this thread was going so well........lol.

[R350Zz33]

then u get someone like blacksmoke who makes a comment and it goes down the ****ter

[Anthonysflying]

Isn't it easier to look at the difference in overall tire diameters than trying to figure out how many revs each tire makes per mile. Should be near 1" difference from rear to front.

As for the safety issue with on and off of TCS or VDC. I would rather have the ability to turn it of than not. How can one be expected to track a sports car if you can't disable the safety controls. This is perfect for autox and street classes.

^ One thing i really give Nissan kudos for is the 100% TCS disable. Most other car companies make it hard to do that. it may be because the Z is part of a more drift/race oriented culture.

I thought we were looking at size variances between old and new tires?