group5

hi guys, purchased the white one from Long Beach Mercedes yesterday. What little time I've had in the car has been great. Kanaan's comment about driving the BS all the time if he could helped with my decision, as did reading this forum.
Naturally, like a lot of you, I won't be able to leave it alone (as I probably should).
Judging from JRCART's "banzai run" in the desert (206 at about 5200rpm) I think this car could use a lower final drive ratio. Anyone research this?

JDB

Congratulations!

Let's see some pictures!

JDB

Jim Brady

Congratulations, welcome to the club. Axel ratio's are fine as you will find out.
Get some break in miles and give us a report of what you think.
Jimmy

alexander stemer

Wouldn't touch the final drive ratio, as it will make all the lower gears senseless. With great respect due JRcart, I don't think I would touch anything beyond wheels, ride height (if you are brave), and cosmetic pieces. The car is great as is, and nothing will make it as fast as cars of equal weight and 150 more hp, or cars of equal hp and 1000 less pounds. Enjoy every mile. AS

Fantasm

except a supercharger

SMP

Congratulations, I'm sure you will love it. I changed a few things on my car, but
never thought of lowering the final drive. Not sure why you would want to do that, unless you prefer top speed over acceleration.

jrcart

Congratulations on the new ride, I just saw a white one in person for the first time this week, I really liked it and I'm not usually a fan of white cars, the white really sets off the carbon fiber accents, even more so than on silver. As for the lower final drive ratios, I assume what you are saying there is no need for 206 mph so why not eliminate some top speed and try to benefit from it down low. Am I correct? If this is what you are saying I believe you would have to actually increase on the final drive (bigger gear), if I'm not mistaken. I am sure there is something out there or someone who will make it for you, but I am not sure you would really benefit anything from it. I think one of the benifits of having a 7 speed is that it allows you to get the good stuff down low as well as having a great top end as well, and close shifts in between. Going with a bigger gear in the rear in my opinion would only hurt you, and cost you a lot more money on tires every year. As I'm sure you have already found out, traction, or lack there of, is a huge issue. The only way I could see it being a benefit would be if you were a very serious drag racer and were running slicks or cheaters all the time, and I'm guessing that is not the reason you bought the car. Leave the final drive alone, and put your money into an Evosport ECU tune and the VRP CF airbox, I am very happy with both. The Airbox is a thing of beauty and did offer noticable gains and better throttle responce.

Have fun with your new beast.....

SMP

Jim, I think you are right, he probably wanted to go with a taller final drive rather than a lower one. If the final drive is taller you gain on acceleration and sacrifice on top speed and lowering the final drive does the opposite. The problem with a taller final drive as you mentioned will be excessive wheel spin in the first three gears. Even with the wider wheels and tires on my car it still has a hard time hooking up. It actually breaks loose in third under full throttle at around 5500 rpm when the torque peaks. I think it would make the car quiet tricky to drive with a taller final drive, especially feeding in a little to much throttle coming out of a turn. I wish the fender flares would be a little bigger, so I could fit 12" with 315's on the rear. That would help the traction issue quiet a bit.
On a different subject, I'm glad to hear you like the VRP CF airbox, going to pick one up next week since they are pretty close to where I live.

ET550

JR, So you feel the airbox delivers the increased HP and TQ that they advertise? I was thinking of getting one but the AMG specialist at my dealership said he spoke to the evosport guys and that they did not believe they were any real gains to be had from the airbox mod and that I was much better off putting the money into the headers and ECU tune. Have you done another dyno after the airbox was installed?

jrcart

What I can tell you is only from my personal experiance. The last time I was at the track I had a better opportunity to change back and forth between the airboxes. I made 4 passes with the stock configuration and 5 passes with the VRP box. Every pass with the VRP box was quicker, anywhere from .079 - .103 quicker than stock. My car already had some airbox work done to it by Evosport, I had to reverse that by purchasing a new lower half of my airbox because, without going into too much detail, the Evosport mods negated the effects of the new VRP unit. The Evosport mods were good, I saw the dyno numbers to prove it, but I feel this is a better set-up that is why I am now running it on my car until I (or anyone)can come up with an even better solution. I am in discussions with Evosport to develop a Ram-air or cowl induction style carbon fiber hood and integrated airbox for my car. They are in the early brainstorming stages of the project, and you would have to call Brad or Bob for more details because although they will be working with my car on this project I don't want to speak for them on any details.

In my opinion, for only $1800.00 you can't go wrong. There is a definate improvment in throttle responce when you are just cruising down the road at 40mph and punch it. There used to be a spilt second lag/hesitation and now it is gone. I had even discussed this lag with Evosport before recieving the new airbox. In addition to the performance gains it is absolutly a beautiful, well crafted unit. Don't believe my opinion? There are a couple other people that noticed the same improvment in throttle responce running around this board.

...just buy it!

BTW, I think headers and an ECU tune is gonna run you a few more pennies than $1800, if not Bob and Brad have some explaining to do........

ET550

I felt the same way originally that for $1800, if it did what it claims, its a no brainer. Its just that when I heard it didn't perform as advertised that I reconsidered. And yes i know the headers and ECU tune are alot more. I have Evosports price list. I am also considering the Kleeman shorties so I can keep the cats since they do emmission testing in CT. In any event, its always good to hear positive feedback from people actually using the product, so thanks for the feedback. I will probably end up ordering the airbox after all.