The BTR 400+ NA Camshaft V2 (BTR-400+NA) is a hydraulic roller camshaft in BTR's stroker-focused LS lineup, developed for naturally aspirated 402-427 cubic inch LS engines operating in the 3500-7000 RPM range.
- Part Number: BTR-400+NA
- Application: GM LS-Series, 402-427 cubic inch stroker combinations
- Camshaft Style: Hydraulic Roller
- Intake/Exhaust Lift: 0.636 in / 0.636 in
- Intake Duration @ .050": 236°
- Lobe Separation Angle (LSA): 114°
- RPM Operating Range: 3500-7000 RPM
- Valve Overlap: 18.5°
BTR tuned the cam timing events to work with either square-port or cathedral-port cylinder heads, paired with long-runner FAST or Victor Jr.-style intake manifolds. It is also compatible with a centrifugal-style supercharger, such as a YSi, F1R, or F1X, or with 250-300 hp of nitrous. In BTR's back-to-back testing, this camshaft made more power from 3500 RPM to redline compared to cams with less exhaust duration, despite the common assumption that added exhaust duration hurts midrange torque.
This camshaft is designed for use with 1.7-ratio rocker arms only, and requires BTR's 0.660-inch lift Platinum spring kit with titanium retainers and hardened pushrods. BTR recommends an aftermarket stall converter for automatic-transmission applications.
FAQ
What engines is the BTR 400+ NA Camshaft V2 designed for?
It's designed for naturally aspirated GM LS-Series stroker engines in the 402-427 cubic inch range, operating from about 3500-7000 RPM.
What are the lift, duration, and LSA specs?
The BTR-400+NA has 0.636 in of intake and exhaust lift, 236 degrees of intake duration at .050 inch, a 114-degree lobe separation angle, and 18.5 degrees of valve overlap.
What cylinder heads and intake manifolds work with this camshaft?
It's tuned to work with either square-port or cathedral-port heads, paired with long-runner FAST or Victor Jr.-style intake manifolds.
Can this camshaft be used with a supercharger or nitrous?
Yes — it's compatible with a centrifugal-style supercharger such as a YSi, F1R, or F1X, or with 250-300 hp of nitrous.
What valve springs, pushrods, and rocker arms does this camshaft require?
It requires BTR's 0.660-inch lift Platinum spring kit with titanium retainers and hardened pushrods, and is designed for use with 1.7-ratio rocker arms only.
Does this camshaft need a torque converter upgrade?
BTR recommends an aftermarket stall converter for automatic-transmission applications.