This article pertains to 97 & up vehicles.
A bad throttle body can really wreck drivability. It can cause quirks that might be impossible to resolve.
A great throttle body might only add up to 1-3 rwhp.
A throttle body can be very beneficial on PD blowers. LSA, LT4, Magnachargers, Whipple, Kenne Bell. A throttle body will barely make a difference in a turbo or centrifugally supercharged application.
A throttle body is helpful on radical NA builds where the stock throttle body was 78mm. A 102mm throttle body over a stock 90mm barely makes a difference in this scenario. The money is better spent elsewhere.
Several times we’ve taken a radically built NA car, hot swap to a larger throttle body while on the dyno and seen less than 5rwhp. Usually it’s 1-3 rwhp. $/hp is not there for most applications.
There is zero harm running a 90mm throttle body or similar on a 102mm intake. The 90mm throttle body will not choke it or hold it back.
Cable specific
There are many poorly made overseas knockoff throttle bodies on the market. There are also several big name manufacturers sourcing their throttle bodies from overseas. They do not return to the throttle stop reliably. The throttle stop position changes depending on temperature. The blades/shaft fit poorly.
Another issue is that their idle air control passage is so restricted they cannot cover the engine’s operating range and airflow needs. So if you adjust them to have enough air while cold. They will have too much air warm and vise versa.
There are several brands that aren’t even worth trying to get to work.
Electronic
A good electronic throttle body is very hard to come by. They must be precisely made. The shape of the throttle bodies throat and the how the throttle body operates at low settings is critical. With newer GEN 5 applications this can wreck torque models.
Summary
In short. The number of applications that can benefit from a larger throttle body is fairly low and the wrong throttle body can ruin drivability especially around idle. There are better places to spend your money. If you need a throttle body recommendation, reach out. In general, we recommend Nick William’s throttle bodies. Not only are they an American based company but the performance and drivability is the best out of any of the brands we have tested.
We do not recommend any throttle bodies found on Amazon or eBay.
