ced357

Hey guys,

I'm heading to a fantastic 1/4 mile event next month and I want to get the most out of the car.

I can either run my stock forged 19" wheels, or my Klassen 20's that weigh 4 lbs lighter per wheel. What's a greater factor in the 1/4 mile, lighter wheels or smaller diameter? Or, will it be negligible?

chawkins2001

Is your beast awd? Neither of the mentioned setups are optimal. You would want to go to 18s or 17s or 16s with drag tires on them. The more sidewall the better so it does not shock the drive train?

ced357

Thanks for the help. Yes, my car is AWD. Unfortunately, I don't have the space to purchase another set of wheels (I have 12 unused wheels in my garage) so I will have to work with my 19's I guess.

At this point I hope I can run my car at all, my shop installed Rado downpipes a few weeks ago and we have been running into trouble.

sdg1871

What problems?

ced357

Initially, my shop had a very hard time fitting the pipes, it literally took two days. Craig from Rado was great and spoke to the mechanics to aid them. I'm still not sure if the pipes were a hair off as my shop claims, or if my shop became inept for a moment Ultimately, my shop had to do some fabricating to get them right. I have used this shop for many mods and they have always been great.

After the install I ran into rubbing issues, strange noises upon braking and flexing.

Finally, my check engine light came on and the car is currently in the shop again. I will know more today.

I know very few have fitted these pipes to the AWD CLS63 and there may be slight changes in the layout. My shop said we are talking about centimeters in terms of misalignment. It's been very frustrating as the sound is fantastic and I don't want to go back to stock.

ced357

For reference, the pipes are catted and I have a renntech tune, not matched for pipes as I was told I don't need it with cats.

sdg1871

Good god that sounds horrible. I had considered the Rado down pipes because they are so much cheaper than the Renntech ones but decided against them as I also got the Renntech tune and the Renntech sport mufflers so I figured getting all components from the same performance company would result in less potential issues. And no one really has a better long term reputation for quality products than Renntech in the AMG tuning world

Based on your story I am super glad that I didn't opt for the Rado downpipes.

slk55er

In case you have not seen my post, here's the link to my experience that you may find of interest:

https://mbworld.org/forums/w218/5446...ml#post6070728

emericr

Sorry to hear about your troubles . See you at PBIR

ced357

Are you signed up to race, or just spectating?

I just got the car back and they said the CEL was non specific and the only course of action is to clear it and hope it doesn't come back. Not very confidence inspiring, keeping my fingers crossed.

emericr

Just spectating. My tires are down to the cords and new ones are on back order till February.
There is no such thing as a non specific CEL lol. They at least should give you the code and what it relates to.
Let's hope it does not come back.

ced357

Yeah, it sounded strange, I'll get the code from them. Thus far the car is running great.

Well, I hope your not spectating as you have a 2014 CLS63 and 2011 SLS to drive I have the helmet, wear long pants.

emericr

Awesome. I am looking forward to it .

SL55_Forever

Since you guys got drag racing on your mind. How do you guys deal with test and tunes? USually you have to wait 1.5-2 hours in line before running. Being on street tires its useless warming them up really. Do you warm up the motor a few minutes before running and just go at it?

Trying to figure out the best technique for a decent time at a test and tune.

emericr

If on street tires, I just avoid the water box, line and go. Since we are in Florida, ambient temperatures never get really cold.
I am not looking at beating the world record so it's more just fun and trying to improve my 60 ft or reaction time as far as I am concerned.
In most of the ones I have been to, I never had to wait more than 30-45 mins between runs.

slk55er

If you really are serious about obtaining the minimum possible run times in a competition, you'll need a strategy for minimizing weight. This includes removing everything possible from the vehicle -- obvious things like the spare tire and jack, but also things like the trunk floor panel, glove box and armrest storage items, rear bench seat, windshield washer fluid, etc. Hundredths or thousands of a second may be significant.

Also, you'll need a strategy for gasoline. If there is gas available at the track, there is no problem in arriving at the track with 1/8 tank and fueling up after every run.