ITB = Individual Throttle Body. 99.999% of all cars have a single Throttle Body that is connected to the throttle pedal…when you step on the throttle, the Throttle body opens and lets more air into the engine. It’s simple & effective, and is the easy choice…except when you see the alternative; enter Harrop!!!
The GT40 has a really unique engine bay that has an integral shroud in the rear clam-shell. While this helps isolate the hot exhaust from the intake, with today’s modern EFI engines there’s usually a longer intake pipe which would interfere with opening/closing the rear clam-shell…the original GT40’s all had Vertical stack carbs, which allowed for this type of rear clam-shell. When searching for options of what kind of Intake we could use, going ITBs seemed the logical choice…while there’s a few options, most come with significant amount of work and horror stories; that’s where Harrop comes in!
Harrop has been a leader in motorsports & produces some really top notch performance parts. Their “Hurricane” ITB set-up allows for use of our DBW (Drive by wire) throttle & has had great performance. This fit everything we wanted, plus it’s a beautiful set-up that will fit right at home in our GT40.
Harrop has been really easy to work with; they’ve been quick to respond via email (the time difference makes phones call a little harder), direct in their communication, and beat their estimated manufacture & delivery time!!
1) Better throttle response. With the typical single Throttle Body, there’s a necessary intake manifold that connects to the engine…which creates a large volume of air; when you step on the throttle, there’s a slight delay. ITB’s significantly reduce that air volume, which lets the engine react much faster to throttle changes.
2) Power: For engines similar to ours, most people have seen descent power gains over the OEM intake…but that’s in large part because the OEM engine is a 6.2L, and we’re stroked to 7.0L w/ a big CAM; so Harrop ITB removes almost all restrictions and lets it breath! (a stock engine would be a different story, as the OEM intake has been proven hard to beat, especially as it’s free).
3) Fitment: We were already going to have to make a custom intake set-up to work in the GT40, so a big portion of the cost was already baselined…making this an easier choice. This fit perfectly into the GT40.
4) Harrop makes it easy: Many ITBs comes with more headaches than they are worth…Harrop solves all of the big issues. A) They work with the OEM electronic Drive-By-Wire throttle. B) The common pressure manifold allows for an easy tap for the MAP (Mass Air Pressure) sensor, and that also helps equalize pressure/flow, which will be especially helpful at idle where ensuring each cylinder is getting the same amount of flow. This is one of the biggest downsides of most ITBs, and why running them on the street isn’t popular…once you’re WOT (Wide Open Throttle), they’re easy, which is why more race cars have them. C) the fitment & OEM Quality ensure everything fits the first time & is robust to daily driving and track abuse.