Well I measured the bores on my 52MM throttle body that I bought years ago and they measured a dead nuts 2.00". That is 50.8MM. At least they are larger than 48MM and closer to the advertised 52MM.

I would be interested to know if anyone else has measured their 52MM throttle bodies and what the results are. Allen

 

Usually when I get screwed it's with a larger orifice...consider youself lucky

 

That's all great, but perform some math. Calculate the square area of the openings using your measurements. Then subtract the area taken by the throttle shaft measurements. Compare that to a TRUE 48mm TB and slightly smaller throttle shaft in an OEM TB, and see what you have gained for your modification costs. That's a good load of dollars for a few tenths of a square inch. I think I'd be complaining to Eledbrock/BBK or whoever sold the thinig as a "52mm" body.

 

Yes, I measured mine. in fact I made a little cardboard checker. one side is 52mm and the other is 58mm. Lets me instantly identify what throttle body I'm looking at, Selling, Buying ect.
fits nice and snugg, How are you measuring yours? i made my checker out of nice stiff cardboard and I measured it out with a pair of dial calipers. Never have I seen an aftermarket TB that was different that what it was supposed to be.-Mike

 

Hi

I measured mine across the bores on the plenum side with dial calipers. I did it a couple of time to make sure and at different spots. Just saw another post where he thought his were 2 inches. Not sure how he measured though and what the accuracy was. Allen