ORIGINAL: Revomad1
ORIGINAL: HPI_Savage_RC
I've used both pipes on the 5.9, and the 086 absolutely smokes the CEN GST7.7 pipe/header setup.
Excess backpressure is not the issue. It's quite the opposite.
Did you remove the baffle but leave the cone in the CEN pipe? It comes with a baffle to control exhaust noise, but it limits performance. Remove the venturi from the 5.9 carb to allow more air and fuel into the engine. I noticed a big jump in power when I did this. It takes a bit of patience to master the tune with the CEN pipe on the 5.9 because it has to be run richer on both the low and high speed needles. If you have limited tuning skills, the CEN pipe is not for you.
I'm not an idiot. I have been running nitro trucks for 4 years, and I certainly don't have "limited tuning skills". We tried every combination of setups possible. Baffle out and cone in did run the best, but it couldn't touch the 086 pipe/header in terms of mid to high RPM performance.
Based on the way you come across, I'm assuming you have never used any of the common buggy pipes on a 5.9. Try it. You'll ditch your CEN pipe within 10 minutes.
Also, removing the venturi will slightly increase top end power, but it will also dull throttle response and mid range acceleration by decreasing the airflow velocity into the engine. I run (or at least try to run) 8mm venturi inserts in all of my engines. This gives a good compromise.