Hoping some of the OG’s of the platform can help me pick the best option. I’m trying to decide what the best mod would be for my E55. It currently has:

Renntech Shorty Headers
Renntech 168 CP
Bosch 010
MK Ultra SLR Trans Tune

I’m assuming it also has a tune for the mods, but not 100% sure. What I’m wondering is, what is the best path to take the car? I know I will need cooling mods like HE and such which I will be doing either way.

I’m more concerned if I would be better off getting a proper set of LTH or going with a stacked setup such as an 83mm pulley and tuning? As both sets of cats are currently in place, would a compromise be to get a mid pipe setup to get rid of the cats and “bottleneck” that inevitably comes with shorties, or am I still leaving lots on the table compared to LTH?

Basically, where should my money go at this point? I bought the car with the existing mods, so just looking to maximize from this point. I’m not concerned about making the most power possible, just want to take it to the next level.

Thanks for your input!

 

https://mkultraelectronics.com/ get a trans tune this is the best. sometimes cleaning up a tune can do wonders too. vs adding parts.

 

Forgot to mention, but I already have his SLR tune, and yes, it is fantastic! I will edit my OP.

 

sounds good!

 

For me personally i found the best mod to be coilover suspension. The car handles so much more direct than on the airmatic. After that i found the steering wheel to be a very nice mod. The stock one in the E55 looks very dated and is huge. There are way nicer ones out there.