48 mm or 52mm

[Achilles]

I've been needing to replace my throttle body for some time now due to a worn throttle plate shaft and was wondering what improvement if any, I can expect from a 52 mm TB. Since my engine has been rebuilt and modified from stock, I now have a custom Fast Chip programed for the stock 48mm. Will I need to burn a new chip for the larger TB? If I go to the larger TB, will I need to up my injector size? ( I still have the 22 lbs.).

BTW, I still have the stock base (ported), runners & plennum.

 

[c4cruiser]

A larger TB really won't do anything unless you have enough internal mods like a big cam, ported and polished heads, headers, port matching and more cubic inches. Once you get to 377 to 383 cid, then a bigger TB will help.

You would probably see more benefit from cutting the air filter lid to allow airflow through the entire surface area of the filter.

 

[Achilles]

You would probably see more benefit from cutting the air filter lid to allow airflow through the entire surface area of the filter.

Already done that. I'm not really interested in more air. I just need to replace my TB and I don't see any stock or refurbished 48 mm out there for sale. 52 mm seems to be what the aftermarket is selling.

Thanks for the reply.

 

[SPANISHVETTS]

The 52 MM sure won't hurt anything. To notice any gain you will need the plennum ported if it was not done when you ported the base.

I do not think that you need a new chip or bigger injectors with the 52 MM TB. The extra airflow only happens during the last 15% of the butterflies' travel. With the speed limits in the US you can not spend much time with the Vette at WOT.

 

[Achilles]

Thanks, that's the answer I was hoping for.