So who all offers an aftermarket TB (52 or 58mm) for a 95 LT1 and what are the shortfalls of each? I've heard more bad than good on the Holley offerings, a mixed bag on the BBK/Edelbrocks. Not much on AS&M or TPiS. One thing I am concerned about; which ones require modificiations to direct the idle air to the stock idle air passages? After doing some searches, I'm still not clear on this. Also, I haven't ruled out porting my stock TB to 52mm.

Thanks,
Rob
95Z28

 

IF anything, port ur stock throttle body. I have a BBK 52mm and it required a decent amount of work to get it to function properly. A 58mm throttle body is completely useless unless u have a ported intake manifold. Unless ur pushing over 400+ Horsepower, it's not worth it.

 

I would just say getting your stock TB ported would be the way to go. I heard that the 52mm will be safe up to 450hp. This guy is going to be porting my tb
http://users3.ev1.net/~thor10/tbodytest.htm
I don't know how good he is, but he is cheap and really does a lot of work to the TB.
JOHN

 

As far as which 58mm TBs have IAC issues, I have a 58mm BBK that I got a few years ago and it seems okay on the IAC issue. I drilled out a hole in it to make it more like the stocker, but it's much closer to the stock design than many of the others. Not sure if all BBK 58mm TBs are the same though.

I'd agree that a 52mm bored out stocker is the way to go unless you have aspirations to make over 400 rwhp.

 

Thanks for the replies. I've got a 383 M6 with 224/230 112 cam, hooker lts and ported heads. I'm just starting to research the 52mm vs 58mm stuff.

Rob
95Z28

 

I would advise the 58mm for your stroker. My stock bottom end seems to enjoy the extra air. I have the 58mm BBK that has been ported to remove the ridges in the ports.