I know people upgrade to 52mm or even 58mm. But when is it actually a good idea to do so. I see some people do it on relatively stock motors. Do they really get any increase this early in their mod stage or is it just a good platform for later. I don't really want to get one until I'm at a point where I almost have to. I'm only interested in getting one if it's a bottleneck now. Plus I don't want to be going too big when my motor doesn't need it. I plan on running NO2 sometime soon so would it be more recommended because of that? Thanks for any info you can give me.

 

upgrade your tb when you get close to 400RWHP

 

I've heard that the stock 48mm is good to well over 400hp. If your N/A you wont have to worry too much. Your engine can only suck in a certain CFM, enlarging the TB wont make a difference unless your engine needs that amount of air.

 

Kevlar and QCK are right. I just finished my stroker with a crap load of mods and finally opted to go with a 52mm. As for the 58mm I would figure thats in the area of 500hp.

 

That's exactly what I wanted to know fella's. Thanks a bunch. Oh another quick question. Since I'm still fairly stock, running nitrous still won't cause me to have to upgrade in size yet right?

 

Spend the money elsewhere, and the stock TB will work fine with the nitrous.

 

Whoops, I knew I forgot something.

 

my car gained only 8rwhp or so going from stock 48mm tb to a 58mm BBK AND doing the !tb bypass