There's a good reason for that. Porting and bigger valves go hand in hand. If you were to only install bigger valves, and that was it - you'd kill the airflow and go slower.:Smarty: That's a fact!! The single best place to spend your time & money is in the heads. Then, the proper cam & springs to match. I'd say the guys were looking out for you, not trying to send you off on a tangent.
I've worked on various types of motors for about 35 years and I've never heard that one before, but I don't know everything, either. A friend did that with his Ford years ago, with no other changes, and he said while it didn't feel any more powerful, it did feel like the motor didn't have to work quite so hard (his motor was modified, but head were stock), so its gotta be doin' something. Fact of the matter is I mentioned valves, not porting. Bob
I totally get that. My point being - you don't want to go with bigger valves without doing some porting. Doesn't have to be a full on stem to stern job. Absolute minimum would be some pocket porting. You HAVE to open up the throat when installing a bigger valve. It's probably safe to assume you're familiar with BBC intakes & ports. Putting a rectangular port intake on an oval port head would be a huge mismatch....obviously. That would totally kill the intake flow. Cutting the seat for a bigger valve, without opening up(porting) the throat would be a similar analogy. For what it's worth.....my last job was rebuilding cylinder heads, among other things. I don't know everything either. But, I do feel comfortable giving cylinder head advice.:TU: Have a good one!:Comp:
POrt size.. The criticism is probably from people with the older style intake manifolds before they started cnc'ing the intake flange of the port. Old styles were much smaller than stock which was choking the cross section and flow. Newer versions should perform much better. SO you can listen to the complains but keep in mind that there is piece of the puzzle being left out. The T/A has potenial above the stock so just know the difference when shopping. If it's older, just accept it has to be port matched.
Larry, Forgive me, I think I missed your point here, earlier. Another problem, related to Larry's above comments, that might come up, would stem from the resulting loss in air velocity (for lack of a better word) due to the larger internal dimensions of the T/A intake. This could result in some fuel puddling, inside the manifold, using unported heads, leading to a constant lean condition in the engine. Bob
Bob, You are forgiven:laugh: I think you are thinking like a Chevy guy. We have plenty of air velocity to spare. That's why Buicks make so much low end torque. We can afford to give some of that up to gain some high end power. Ported heads really show their stuff at higher RPM's. That's why all the 350 guys are salivating at the prospect of a single plane manifold. If you are talking about a completely unmodified engine, the only reason to use the TA Manifold would be weight loss and cooler running. You might lose some low end under your scenario although I've never seen any hard numbers to suggest that.
Larry, You got me. :blast: Primarily, I am a Chevy guy, but I do like the Buick's, too (actually, all the makes under GM). I always thought the main reason for the 350's making so much low end was the large crankshaft that engine uses, but your explaination makes total sense. Thanks for showing the other side of that. Bob
