Technical Information for Factory Mustang 5.0 & GT-40 Intakes.

Highlights of the SEFI (Sequential Electronic Multipoint Fuel Injection) 5 Liter Intake Manifolds.

1986 - Fords new two-piece tuned-runner intake was optimized for maximum torque output at low and midrange rpm. All Ford's 5 liter passenger car engines used the new SEFI system, though CFI remained in service for some truck applications.

1987 - 1993 - In 1987 the upper manifold plenum entrance duct was enlarged to match the 1987's larger throttle body. The lower intake was a carried over from 1986, both it and the revised upper continued unchanged through 1993

1993 SVT Cobra - Because the 5 liter H.O. intake was designed for low speed tourque it does not flow particularly well at high RPM. The SVT Cobra for 1993 used a less restictive "GT-40" version of the SEFI manifold that offers a better airflow advantage.

1994 - 1995 - Primarily due to hood clearance issues with the SN-95 Fox-4 Mustangs, the 5 liter H.O. uses a lower-profile (MN-12 type) upper intake section that uses a dog-leg inlet elbow rather than the earlier straight inlet. The lower runner section of the 1994 intake has some added clearance reliefs for fuel system componets, but is other wise little changed from the 1986 E6SZ casting.

1994 - 1995 SVT Cobra - Again due to hood clearance issues the SN-95 SVT Cobra uses a lower-profile GT-40 based upper intake section, this section is approximately .4375" lower than the 1993 version. To equalize airflow, plenum volume was increased as was runner width. A 40 degree dog-leg inlet elbow is used providing a direct flow from the throttle body to the plenum.

1996 - 2001 Explorer - After the 5 liter V-8 was discontinued in Mustangs it was still used to power the 1996 and on Explorer and Mountaineer. The Explorer GT-40 based SEFI intake was redesigned to optimize torque output. The cross over section is tapered and reconfigured as an inverted "T", the runners are also taller and tapered to maintain optimum flow velocity.

Ok now for the stuff you can put numbers too.

5.0L SEFI System Weight Chart(pounds)(*1)


Factory 5.0 H.O.

93 Cobra GT-40

Explorer GT-40

FRPP GT-40 (*2)

Lower Intake Manifold





Upper Intake Manifold





EGR Spacer





Throttle Body





Total Weight





*1 Weights are based on single production components and taken from various sources.

*2 Motorsport FRPP tubular upper with Explorer cast GT-40 lower, OE Mustang EGR spacer and OE throttle body

An intake is not much good with out a throttle body!

Throttle Body Flow Rate Comparison (*1)

Throttle Body Diameter (mm)

Airflow (cfm) (*2)


580 - 600


625 - 650


675 - 700


750 - 775

*1 Flow capacities are approximations and can be compared to traditional carburetor flow rates.

*2 Airflow rates are bench tests at flow depression of 2.0 in. Hg.

A Visual Guide to Factory Mustang 5.0 & Explorer GT-40 Intakes.

* Disclaimer: I am not a certified mechanic and in no way imply that I am. Technical references listed in this article are for reference only and are believed to be correct at the time of this writing. Use this article and the information contained herein at your own discretion.

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Last Update September 14, 2015