13B-REW Lower Intake Manifold

 Wanting to make over 400 WHP  or just want better flow for your more street friendly build? It's a good idea to change out your stock lower intake. We've maintained the smaller primary and larger secondary runner design to keep a bit more mid range then 4 large runners, but still be able to handle much higher numbers.

  For best results, port matching is recommended, but the manifold can be bolted on for better performance without any work. We've designed the ports to only require blending in to the runners about 1" for port matching so it doesn't take any expensive porting tools, just more common burs and sanding rolls. We've also casst the main lower flange with pads to aid in the addition of Semi-P Ports.

 The manifold can still utilize the stock side feed fuel rail with some clearance work, but aftermarket top feed rails for 2 injectors or  4 injectors top feed rails are a direct fit. If your planning on upgrading your primary and secondary injectors, do it with a single rail and simplify your fuel system at the same time.

   One of the big concerns with stock manifolds is the front to rear balance in flow. We've redesigned the front to rear secondary ports to have matched flow rates, which is nearly impossible on a stock manifold, this balanced flow is especially important in higher boost where it matters most.

  Because this is a new casting, there is no thinning of the port walls from extrude honing or hand porting to obtain high flow rates. This also means there is still room for an all out race port never before attainable with the stock piece and at 12% lighter than stock. With removed heat riser passages and smoothed exterior, this piece has less opportunity for heat soak and much cleaner look.

  This manifold is designed to use standard rubber o-ring injector installation. Metal spacers/adapters may not fit due to some modification of the injector port size. If you're converting to top feed injectors, it does require injector tip spacers or disc type aluminum adapters sold by many top feed rail manufacturers. 

  Expect to re-tune your motor after installing the manifold, the increase in flow rates can change the air fuel ratios.