hi guys, i am looking into the vortec tpi setup for my motor and was wondering if the 1.94/1.5 valve sizes are a little bit small or not with teh 170 cc intake runners. they will be going on a 355 tpi roller block with the lt4 hot cam..... what are your opinions on this..thanks

 

Chevy Hi Perf magazine did some dyno testing w/ these a year or so ago and built over 1hp/cube with the Vortecs straight from the box.

 

and this was with tpi? sounds impressive.....

 

The power that comes from heads is always not in size. Velocity and efficiency is what makes power and Vortec is the best out there right now for the price. Can't beat 90's technology.

 

Before I built my engine, I did a lot of reading on the Vortecs. I have found, as many magazines did, that enlarging the valves did nothing to offset the cost of having them done.

 

so what are you trying to say....sorry, i'm sick right now and not thinking.....

 

The heads are pretty much as efficient as they'll get, exactly as cast.

 

ok, gotcha, sorry but this headache is killing me,lol

 

One thing I would do no matter what. If you look just under the valve seat, you will see a few machining ridges. Take those out. I bought 2 SA Porting kits and went very slow. I don't have pics of before, but here is some of after.

 

Here is another

 

yeah, that looks like it would have needed some work done. thanks a lot. prolly didnt take you too long either. worth it though.