Project FD RX7 Restomod: Part 26 – BorgWarner EFR Turbo System and TurboSmart WG

Before building our engine in Part-13 and Part-19, we originally planned on using the C-type turbine housings due to their drop-in nature with an internal wastegate that greatly simplifies the downpipe and exhaust requirements.  Turbosource offers off-the-shelf downpipes for this turbo system.  After going off the deep end with our engine build and porting work, the D-Type turbine housing, 1.05 A/R, and external wastegates were a far better fit for our increased performance, RPM, and power goals.

EFR 8374

This turbo features a 62.6mm compressor inducer, an 83mm compressor exducer, a 74mm turbine inducer and a 64mm turbine exducer.  Some turbo manufacturers quote their turbo sizing by the compressor inducer and turbine exducer dimensions, which would make this turbo a “63/64” by that nomenclature

EFR 9180

This turbo features a 67.7mm compressor inducer, a 91mm compressor exducer, a 80mm turbine inducer and a 74mm turbine exducer.  This turbo would essentially be a “68/74” by that nomenclature.  This turbo is particularly special to me because it was the turbo that powered the FXMD Time Attack NSX that I drove to many track records.

Prior to our FD’s engine fire in Part-10, we purchased the Xcessive Lower Intake Manifold (LIM) to improve the flow distribution of air to both the front and rear rotors.  You can see that both banks of runners are identical mirrors of each other compared to the factory LIM (right), which has uneven runner lengths.

The Xcessive LIM also does not have the extra emissions ports that are blocked off in many factory LIMs.

When we started to build our 13B REW engine and decided to semi-peripheral port the housings, we could no longer use the Xcessive LIM, and had to buy a Semi Peripheral Port (“Semi PP”) LIM from Billet Rotary with runners cast into the manifold for the peripheral ports.  Note, that there are two additional intake holes to feed the rotor, bumping the total number of inlets to six!