Old vs New ( WEISTEC INSIDE)




I actually performed a test on my spare manifold last year and deleted the flaps. It didn't make any note-worthy gain or drop in power according to the butt-dyno, nor did I get any CEL. I eventually reverted back to having them back in for the sake of logic telling me they would aid flow by directing air better when they're open. I mean...they're a small obstruction in themselves sure...but without them, i'm sure there would be a lot of turbulence inside the manifold. On the basis that I couldn't notice any change with or without them, i'm guessing the drop/gain must have been in the +/- 10hp range. Makes you wonder why we didn't get a better manifold for stronger peak power like in the SLS
'tis a pity I didn't have my proper HP Tuners logging software back then, as I'd have been able to have identified an approximate gain or drop in power. Oh well...I had a look at his log and while there's more power in there up top when he upgrades the fuel system and revises the tune for E85, there wasn't a dip in timing around where the dip in power is on the dyno plot. I don't know how it will learn it's way around that dip, but I'd love to see it all the same. I'm sure that ECU 'learning' does exist, but I struggle to understand what it exactly does. For example, if the fuelling, timing and airflow is the same from dyno day to say, a month later....what makes the car run better? I'm experiencing this on my car at the minute. Not a substantial change, but an improvement nevertheless, yet I can't attribute it to anything.
Sorry for the slight deviation, Brad
I'll go and cook dinner now
Last edited by mr747; Jul 26, 2018 at 07:00 PM.
The Best of Mercedes & AMG





brad are u hitting those runs with meth?
So there was a 60hp gain peak or through most of the curve? Not used to those kw graphs myself.
Brad, do you get belt slip with the 57mm?? Where can I get one, weistec didn't have any when I asked. Thx
brad are u hitting those runs with meth?
So there was a 60hp gain peak or through most of the curve? Not used to those kw graphs myself.
Brad, do you get belt slip with the 57mm?? Where can I get one, weistec didn't have any when I asked. Thx
No meth it was disconnected
complete bolt on
No change in tune
im trialing 57mm this week
60whp gain through whole range

We ran into some issues with the fuel rail so we had to weld some extra tabs to keep it clamped down
These runs are without ice in the tank and you can see iats are getting up there
We will try and push fo a little more power this week and then hit the track
Just letting you guys know at these power levels the PREFL m156 engine is starting to show some wearing around rings and bearings we have found some material in the last oil change
Might be time for a build sooner then later





