I want to get a bigger throttle for my motor but don't have the extra money for extra upgrades, so what size throttle body would work fine on a unmodified motor.

Things that I have done is cold air intake and full exhaust kit.
​​​​​​

 

The stock one is more than adequate. A larger T/B on an otherwise stock engine will only lose power in the midrange... there will be no gains in peak power. Save your money.

 

I want to a bigger T/B but nothing massive just wondering cause I'm between a 62mm and a 66mm T/B if I can without bogging the power I want the 66mm but I'm ok with the 62mm if that wouldn't bog the power.

 

In my opinion you're way better off saving your money and getting a tune to maximize the benefits of the other mods you've already done. From what I've heard (may or may not be true, so take this with a grain of salt) bigger throttle bodies only really help when accompanied by port/polishing work, cams/valves etc.

 

Maxbore.com throttle body boring service and repair

I used them with great results

 

With naturally aspirated engines, you don't NEED a larger throttle body until the blade opening becomes a restriction !!! The only way to KNOW this is to datalog a full-throttle 3rd or 4th gear pull to redline and if the MAP values are greater than 2" of draw, then a slightly larger throttle body will provide a bit more top-end power without affecting low and mid-range performance. This idea of just getting a bigger throttle body because you think "more air equals more power" is a total fallacy and misguided.

I have done business with them for years with great success. However, their service can be just as, if not more, expensive as buying a new aftermarket throttle body in some cases. This means that their service will be the better choice when you need to maintain a stock throttle body (racing rules, keeping certain components, etc). For example, I had my RSX-S throttle body modified by MaxBore because I wanted to keep my cruise control and aftermarket throttle bodies for "K" series engines do not have the second wheel required for the cruise control cable.

Finally OP... here is a practical example: My RSX-S K24/20 makes nearly 260 wheel HP on a 64.5mm throttle body, so if you think you need a 70mm T/B for your bolt-on H22A... you aren't listening.

 

JR is right on the money here. Bigger does not always mean better. A throttle body too large on an NA engine will slow down air velocity to a point that it causes detrimental effects on how the engine behaves and power output in certain areas.