TBSS/NNBS INTAKE FREQUENTLY ASKED QUESTIONS (FAQ)

The TBSS returnless fuel rails can be adapted to your OEM return style fuel lines by utilizing a C5 Corvette fuel filter (found here) between the TBSS fuel rails and your OEM lines. The fuel filter will snap directly on to the inlet of the TBSS fuel rails if the inlet is bent upwards carefully.  However, we typically run a short section of fuel line from the outlet of the filter to the inlet of the fuel rail so that the fuel filter can be mounted further forward to allow for more fuel line clearance at the firewall.  Your factory feed and return line will snap directly onto the inlet and return of the C5 filter/regulator. The fuel filter has one 3/8 male inlet, one 5/16 male return, and one 3/8 female outlet. The C5 Corvette fuel filter has an internal fuel pressure regulator and regulates to a static 58 PSI of fuel pressure. Be sure to account for the static fuel pressure in your ECM programming.

Yes, sometimes an adapter harness is required for the MAP sensor depending on your OEM style. However, your factory 99-07 truck wiring is long enough to reach the new locations of the MAP sensor and EVAP solenoid. The MAP sensor wiring sometimes needs to be removed from factory wiring loom, but the wire length is more than sufficient to reach the new location. The TBSS EVAP solenoid is plug and play with your 99-07 GM truck harness.

There are a number of ways to adapt your existing EVAP lines, but the simplest is to use our plug and play EVAP adapter kit available here.  Alternatively you can cut your OEM line to the correct length and use a small section of fuel injection hose to connect the new TBSS EVAP solenoid to your existing EVAP line.

The throttle body opening on the TBSS intake is 90mm.

The stock intake bolts can be used, but the intake manifold bolt isolator (rubber grommet) will need to be removed. The TBSS intake does not use intake manifold bolt isolators. Alternatively, we have bolts that are compatible with the TBSS intake manifold bolts available for purchase found here.

Tuning is highly recommended anytime changes are made to the induction or fuel system. This intake is a substantial change to the induction system and if your existing fuel injectors are not reused the injectors included with this intake may result in a significant change in fuel rate as well. Because of these changes, a tune revision is highly recommended.

The TBSS intake utilizes injectors that have an EV6 style plug. Depending on your existing injectors, adapters may be required. The correct injector wiring adapters can be found found here.

On a 99-02 truck, several changes need to be made. You will either need to utilize 3-bolt to 4-bolt throttle body adapter to retain your OEM throttle body or purchase an aftermarket DBC style throttle body (90-92mm recommended size - We have a selection of DBC throttle bodies available here). A new throttle cable bracket will be needed, which we have available for purchase here. 99-02 trucks will need to convert the returnless TBSS rails to adapt to their existing fuel system (see above). Multec II to EV6 style injector adapters will be required (found here). EGR must be deleted (this intake has no EGR provisions). Minor changes are required to adapt your existing EVAP lines (see above).

Although this intake is more of a "bolt-on" for 03-07 models compared to earlier trucks, some modifications will still need to be made to adapt the intake. This intake utilizes a 4-bolt 90mm throttle body. You will either need to utilize a 3-bolt to 4-bolt throttle body adapter to retain your OEM throttle body or purchase an aftermarket, LS2, LS3, or 2008+ Silverado DBW style throttle body. We have several DBW throttle body options that will fit the TBSS intakes available found here. If you change to one of the throttle bodies listed, your truck will require an X-Link throttle signal converter to operate with your OEM TAC system (found here). This intake does not have the hose barb for your PCV fresh air side, so you will need to plumb your PCV fresh air side into your air intake somewhere before the throttle body. If your truck currently has EGR, it will need to be deleted (this intake has no EGR provisions). See above for EVAP modifications. If your truck does not currently use EV6 style injectors, adapters will be required (found here).

The L92 intakes have LS3 style square port runners. The TBSS intakes have LS2 style cathedral port runners.

The TBSS intake’s desirability comes from the fact that it performs exceptionally well down low, as well as at higher RPM. The TBSS intake outflows aftermarket intakes below 4500RPM, but still makes the most power of any factory cathedral port Intake above 6000RPM. I utilize a TBSS intake on my personal truck, which previously had a cammed LQ4 that was shifted at 6800RPM. My datalog showed very little, if any, restriction on the intake side even at that high of an RPM. It was certainly one of the best changes I made to my truck and was night and day vs the stock truck intake.

The TBSS intake is a substantially improved intake design vs the stock 99-07 truck intake. The TBSS intake’s inlet is 12mm larger in diameter and the TBSS intake features significantly improved runner design. Exact power gains cannot be predicted due to varying differences in engine combinations. However, from personal experience on my own truck (cammed LQ4), I can say that the TBSS intake was absolutely the best bang-for-the-buck performance modification made. See the article linked below for a dyno comparison done by Hot Rod Network that compares the TBSS intake to 19 others, including the stock 99-07 Silverado intake.

found here:

20 LS1 Intake Manifolds Tested!