I’ve had my ‘04 E55 for almost a year now and after a few trips to the track and lots of research on this forum, I think I’ve got a pretty good idea of what the car is capable of. I’ve always loved drag racing, but I’ve never been able to have a car that is fast enough to be interesting at the dragstrip and function as my daily driver and kid-taxi. As you all know, that’s precisely the scenario in which the E55 excels!

My plan over the next year or two is to build the Beast into an excellent bracket racer while retaining 100% of its streetability and reliability. That means focusing on mods that will increase consistency more than those that make it just go faster. Here’s my list of mods, in the order that I plan on doing them. Right now the only improvement the car has is the Bosch -10 I/C pump.

1. PedalBox
I’ve had the car at the track about four times now and the most difficult thing for me is getting it to launch consistently. There is a noticeable lag from the time I step on the gas until the engine responds. I think the PedalBox will help with that. It’s different levels of adjustability should also help to dial-in a good “rollout” for the car.

2. Slicks or Drag Radials
This will help the most. All of my runs so far have been on 265-35-18’s (Cheapo-Federal tires) with traction control on. Even with those I managed a best 60’ time of 1.861s, with a best ¼ mile time of 12.40. Better tires should put me in the low 12’s with 1.6-ish 60’ times. I plan on running the CLK 16” wheels with Mickey Thompson drag radials so I can put them on at home and drive to the track.

3. Reinforce rear differential mounts
I’ve read plenty about the “Dead Body in the Trunk” issue. I think a good winter project will be to reinforce that area of the frame before it becomes a problem.

4. Belt Wrap Kit
I’ve got the supercharger belt “chirp” right now and it’s kind of annoying. It’s not hard to imagine how a slipping S/C belt will make for inconsistent E.T.’s. The BWK should help, plus it will give a little extra HP.

5. Smaller S/C pulley and tune
I really don’t know if this will make the car more consistent, but with the other changes it should get me consistently into the 11’s, and who doesn’t want to say their grocery-getter can run 11’s!

6. Larger Heat Exchanger
See #5.

7. BC Racing Coilovers
I’m not a huge fan of the Airmatic, and it seems having it would add to the inconsistencies during launch. A set of adjustable coilovers will allow for tuning the weight transfer during launch as well as setting ride height. As a bonus you lose the potential for a catastrophic air bag failure to leave you stranded on the side of the road!

I think the above combination should get me in the mid-11’s without sacrificing any reliability or making it too ‘complicated’ for my wife to drive. What do you think? Have I missed anything? I welcome everyone’s input.

 

You've missed headers. But sounds solid.

 

+1...

I actually would say this should be your list :

(1) breathing out / exhaust - headers
(2) breathing in - TB + (headwork if you have the appetite)
(3) cooling - split cooling + KC + 3 - 5 gallon tank
(4) fueling - looped rail + larger injectors
(5) more boost - however you want to spin the SC faster
(6) slicks
(7) tune tailored to your fuel & mods....
(8) great datalogger

 

pedal box ? ...just hold gas and brake to preload and go !!!!

 

I get that headers are usually one of the first mods to make you go faster, but do they help you be more consistent? Headers for this car are crazy expensive so they'll be far down the list unless someone can make a point for consistency.

 

If your after consistency you need to greatly focus on cooling since the car will get hotter therfore slower as you run.

 

Good point. Does adding a larger H/X require a tune, or can that be done all by itself?

 

No you should not need a tune as its just helping cool the system. You can also get a trunk tank giving you the availability to add ice. Split cooling should also be a must.

 

It's a slippery slope your starting down. When I bought my car I thought I'd only do little stuff and here I am a year later with most all the performance stuff you can get and considering the nitrous path.