Has anybody bored out their tb to 48 mm??? It seem's like i heard someone doing this sometime on here. And if someone has can they tell me or show me a pic on how it was done and what will be needed

 

You'll need a giant manual mill and an offset boring head, or some type of fly cutter. Or a 4 fluted 48mm end mill (hahaha) j/k.

Then you'll need alot of patience while you indicate the whole thing in to make sure that it's centered.

Once you get all that done you'll need to find a stock TPI thottle body for the plates. I redrilled the throttle plates because the holes do not match the holes in the throttle shaft.

There are some little holes in the bore that CCP emtpies out into. You will prolly end up cutting real deep into these like I did. So we made some plugs on the lathe and jammed them in. They protruded into the bore a bit so I ground them flush with a Dremel.

 

another pic...

 

and another...

 

I just got my throttle body back. I found someone who would bore it out to 48mm. Cost me $30, but hopefully it will work out good. I'll take some pics and get a link to them as soon as I can.

 

$30 not too bad! I'm getting ready for my 2" bore experiment. We made .050" thick sleeves and now we're gonna bore the stock Astro TB out to 2.050". Then shrink fit the sleeves in...

 

How are you going to do that? Put the TB in an oven and heat to 150 or so, put the sleve in liquid oxygen to shrink it? Put two and two together and you'd have a pretty tight fit there. I guess you could get by with the freezer though.

Yeah, all I need now are 350 injectors and my TBI project will be done. I just needed a little more flow for a 327 since I might be taking it to a bit higher RPMs than a 305 or 350. PLus I'll be able to flow so much more at the higher range too.

Thanks for the idea of this Astro. Your pics helped out a lot too.

 

astro. you NEED to let me know how that turns out.