Next, we are already underway with:
Phase 1: Engine Performance Upgrades!

Based on all of my research and assistance from fellow forum members, there isn’t a ton that can be done to the 4.7L V8 without pursuing forced induction. And unfortunately forced induction, unless OEM factory equipped, isn’t allowed in the 4600 class.

The stock 4.7L V8 is rated at 260 @ 5,400 rpm Horsepower and 306 @ 3,400 rpm Torque. Our goal, which may never been fully verified, is to get above 300 Horsepower and around 350 FtLb Torque.

How?

Well, let me introduce our first round of sponsors:
aFe Power:
Their 54-82502 Magnum Force Stage-2 Si Pro 5R Cold Air Intake is a no brainer:
https://afepower.com/afe-power-54-82...-intake-system

It’s got great reviews, has the Magnum Shield pre-filter option for all the dust we’ll encounter at KOH, and their customer service is second to none.

Doug Thorley Headers:
These guys are awesome. For those who own 4th Gen 4Runners, you already know them. Their headers are really the only proven, reliable option for the 4.7L V8 and therefore the only thing we’d run on this race build:
2005-2009 Toyota 4Runner / Lexus GX470 4.7L Short Tube Headers

URD – Underdog Racing Development:
Gadget, who runs URD, is a legend in the Toyota enthusiast world. I’ve known of Gadget since I was building up my ’98 tacoma in the early 2000’s. URD products are second to none. I reached out to Gadget and asked him for recommendations for this build. Here’s what he suggested:

- URD “Offroad” Y Pipe for 2005-2009 4Runner V8:
https://www.urdusa.com/urd-off-road-...09-4runner-v8/

- URD MAF Sensor Calibrator – Universal:
https://www.urdusa.com/urd-maf-sensor-calibrator/

- URD 2005-2009 4Runner Fuel Pump and Filter Upgrade Kit:
https://www.urdusa.com/urd-2005-2009...r-upgrade-kit/

- URD 170 Degree Performance Thermostat for 4.7L V8:
https://www.urdusa.com/170-degree-pe...uz-fe-4-7l-v8/

And in order to make sure our MAF Calibrator is used most effectively, we also purchased a UEGO Air/Fuel Ratio Gauge from AEM:
https://www.amazon.com/gp/product/B0...KIKX0DER&psc=1

Magnaflow Exhaust:
I’m still waiting to see if our Magnaflow sponsorship will be approved which included high-flow cats and a race series muffler. In the interim, we have a Magnaflow Cat-Back Exhaust that should close out our performance mods nicely:
https://www.magnaflow.com/products?partNumber=15781