I was looking on the Lingenfelter web site and they recommend the 52mm for stock or lightly modified 305's and 350's and a 58mm for 350's with more mods. I was thinking a 58mm would be too big for an LT1 with even a cam and heads. I know if you have major mods like a big cam and high flow heads or supercharger or something like that, you should go with a 58mm. I have ported and polished heads decked .010 and the hotcam kit. Should i go with a 52mm or 58mm? Thanks.

 

i have an stock tb ported to 52mm with airfoil for 140 shipped let me know. thanks

 

How much more do you plan on modding the car? If youre at about your limit, id say even keep you stock one or just go for the 52mm. Your stock TB is good till around 400rwhp, then it becomes a restriction(thats what I hear on here all the time at least). 52mm will be good for a while, the 58mm isnt quite necessary but it wont hurt your performance. SO i guess my post doesnt really help you out at all. LOL

 

I'm running stock heads with the mods below. I just installed a 58mm because I got a good deal on it. At that time I put some 30# injectors in as well. I can say there is definately a difference on the top end...pulls a lot harder from 4500 up!