I got the EBay 50mm almost a a year ago, it's was a great upgrade on my 318. Gave me better low end power but at WOT it felt the same could have made a difference but I couldn't tell.

 

I like my fastman tb. I think it's a 51mm. I noticed a little less drag on take off and high speeds. Felt like I lost 500lbs. I will admit that a lot of this may be because I went from an original dirty tb to a clean and polished tb.

 

So I guess I will try the eBay throttle body just because of the price point. Everyone seems to think it will perform just as good as the fastman. Thanks for all the help guys.

 

Let us know how it does for ya!

 

What size is the stock throttle body on a 5.9 ?.

 

Same as the 5.2L... I believe they're both 50mm.

 

The top is 47mm and the bottom is 50mm.