Kumho V700 rears = best performance mod on my car so far. Amazing tires.

[PhoenixGTS]

Now that I have over 100 miles on them, I can say that putting a set of 335-30-18 Kumho V-700s on the rear is the best "performance" mod on my car. After 9 months of ownership, I finally have a car that is sorted out. I can launch now and I can give it some throttle going around a turn without risking a 360 each time. Just the confidence alone makes me so much faster in the car it is amazing. I think the Gen II has four huge flaws: 1) non-ABS brake balance is horrible; 2) lack of traction is scary; 3) gears are too tall; and 4) if you live where the sun shines the cooling system is marginal at best. My goal has been to fix these issues, and what I have found is that in terms of bang for the buck and overall effectiveness, here are my favorite mods:

1) Sticky tires = Kumho V700 rear and Ectsa MX on front;
2) Tom's 40mm rear brake caliper upgrade;
3) 3.55 gears (I'm guessing on this one since they are not in yet); and
4) big radiator and overdrive water pump.

Again, things like the tires, brakes and cooling are really confidence inspiring and allow me to drive the car much better in that I finally feel like I can predict what is going to do. I call that an effective performance mod. Doesn't make 200-300 rwhp like a supercharger, but works nonetheless.

 

[BlueGTS]

I have a pair in the basement but don't want to put them on until I get some 3M protection. I don't want to sandblast my rear quarter paint. I really need to get it done ASAP as street tires do not hook in 1st from a roll with the ROE, not that I expected them too. Giving rides with spinning tires is not half as impressive as when it dead hooks in 1st and 2nd.

 

[viper spray]

Now do the fronts.

 

[PhoenixGTS]

I have a pair in the basement but don't want to put them on until I get some 3M protection. I don't want to sandblast my rear quarter paint.

Obviously I cannot much comment on the sandblaster issue after only 100 miles, but I can say that I do not hear grit and gravel being thrown up like others have reported. Then again I do not live where they sand the roads in the winter.

 

[Heysie]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Like Viper Spray says, do the front. If you really push the car into a corner, you will have now understeer, and that's a nono for a supercar.

 

[PhoenixGTS]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Like Viper Spray says, do the front. If you really push the car into a corner, you will have now understeer, and that's a nono for a supercar.

They do not make the proper size for the front, plus oversteer is nice and safe.

 

[V10TT]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Which wheels do you have now on the car on 18"?
BTW, I remember your car from back in its days in Miami...

 

[PhoenixGTS]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Which wheels do you have now on the car on 18"?
BTW, I remember your car from back in its days in Miami...

I sent you an e-mail about my car back in its Florida days. I bought a set of used 18" stock wheels in good shape but with some clear-coat issues. I had them and the gas cap painted silver (it was having clear-coat issue also) to match the car, and painted the intake and valve covers wrinkle grey. There is now no color or shiny on the car. I like the look - it is a love it or hate it deal for sure.

 

[XS TORQ]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Which wheels do you have now on the car on 18"?
BTW, I remember your car from back in its days in Miami...

I sent you an e-mail about my car back in its Florida days. I bought a set of used 18" stock wheels in good shape but with some clear-coat issues. I had them and the gas cap painted silver (it was having clear-coat issue also) to match the car, and painted the intake and valve covers wrinkle grey. There is now no color or shiny on the car. I like the look - it is a love it or hate it deal for sure.

Let's check out the wheels, gascap, and engine compartment....
Pics or ban! ;-)

PS: I think you'll like the rear gear change.

 

[ERDOC]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

I'll be running Kumho V700 in the rears along with Kumho MXs in the fronts soon on my 18" Forgelines. I have been running the 17's for several weeks and like the grip in the rear even with 820 rwhp.

 

[PhoenixGTS]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Let's check out the wheels, gascap, and engine compartment....
Pics or ban! ;-)

PS: I think you'll like the rear gear change.

I was hoping to get the pics done after the detail job this last weekend, but since I have to mooch a camera from my folks, then figure out my free hosting space it did not get done. Viper guys will either love it or hate it, and a non-Viper person probably would not even know it is is not stock. Need to finish the taxes this week then I can get on those pictures. I am definitely looking forward to the gears now that I have some grip.

 

[Jim Wilson]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

I have a brand new pair of Pilots in my closet.....it sounds like I may have to sell them and go with Kumhos.

 

[PhoenixGTS]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

I have a brand new pair of Pilots in my closet.....it sounds like I may have to sell them and go with Kumhos.

Especially if you get that blower going!

 

[Jim Wilson]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Hey, you just reminded me. When I get the SC on, I'll probably want to go back to 3.07's, since I'll probably have around 850 rwhp so if you haven't bought you 3.55's yet maybe we can make a deal?

 

[rcdice]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Phoenix,
When you get time to post some pics, would you also post a close-up of the "fitment issue" with the V700's? Others have talked about it not meeting the edge of the rim like the Pilots do.

 

[BLWNASP]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

I really like the information you put out PhoenixGTS. You are speaking my language. Now of course it does not get near as hot in SD, but it get's into the 90's inland.

I have had the Viper for about 5 month's now and draw the exact same conclusion. I plan on switching the rear tires really soon, getting sideways is fun, but not when you're really trying to take a turn (hard).

And I have noticed my car is starting to get over 200' degrees going towards 210-220 just as the weather has gotten a little warmer here. Thanks for the input on how to correct it. Should I just go with the bigger radiator to lower the temps 10-20 degree's?

I appreciate you're learning curve.

If I can give anyone a tip it would be this. The first thing besides the shifter I changed in the car was the speakers. I bought Blaupunkt transparent line seperates (6 1/2 $ Tweeter) and they are terrific. Now they will not win soundoff's but they sound very clean, not harsh and they play plenty loud. I am using an amp, but they are efficient speakers. Best part about them is I spent $49 for the pair. They were 70 percent off!!! Soundomain.com has a great deal on them. And they look good, plus easy install.

 

[RX VIPER]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

Phoenix- how do that handle at higher speeds? I've had the BFG's on my car for about a month and really like the grip off the line, but doing 120+ and going around slight curves I felt a little on edge and backed off. Guess I need to get more used to them. Did you also notice if the ride quality is more rough and bumpy than with the Pilots?

 

[PhoenixGTS]

Re: Kumho V700 rears = best performance mod on my car so far. Amazing tires

1) Jim I already have the differential with the 3.55s and the upgraded Unitrax posi unit (+ super secret driveshaft yoke).

2) RCDICE the V700 do look odd in that the rims sticks out. For example, if you knock over a tire, the rim would hit the garage floor - not the tire. I'll get pics when I take pics of the paint mods. One drive and you forget all about it.

3) BLWNASP if you read the service manual (and talk to factory folks) it pretty much says you are fine unless the guage is pegged. I (and most people I bet) think that is crazy. You are definitely safe with that 210 in the chilly SD area, but for us desert rats think of this, assuredly when the temps are huge like 225+ the PCM has to me picking it fuel and timing from a more conservative table with the result being that you should be faster with a lower coolant temp. Funny thing - when I bought my car on June 29, 2004 my GF and I flew out the Huntington Beach and drove the car home to Phoenix. The car was about a mile from the ocean so we drove it down to the beach before heading home. It was so freakin' cold we stayed about 10 minutes and bailed out. Within hours we were in 100+ temps (at night).

4) RX VIPER don't forget that unlike the BFG drag radial the V700 is a roadrace tire so it is meant to turn corners. I have been a bit over 100 so far and it felt fine. Ride has not changed a bit (I have 30 psi all around). I was thinking that maybe since the MX are 275 instead of the 285 coming off that tramlining might improve (only seems to be a bother in the first few miles of a drive) but it is only marginally better which make sense since the new tires ended up being just as wide as the old fronts.

I am having so much fun being able to put more and more throttle on in turns. I keep pushing it, but have not found the limit yet and I am WAY beyond what the Pilots would ever do. I think it is finally time for my Porsche-driving 64 year old dad to drive the car (he cannot get into much trouble at all now). You can definitely feel that the V700s out back kick butt on the Ectsa MXs up front, but as I said before, understeer leeps you out of trouble by signaling you early compared to the snap oversteer before. So far so great.