I plan to do it myself. But I still don't understand why it would run richer. The manifold is after the air and fuel are mixed. I won't be changing anything that has to do with the amount of air or fuel it is taking in, only the path it travels getting to the engine after it is mixed. It's still the same mix.

Bru-

Not quite sure of the reason myself...but both Doc and Gram said it's the case, and both are FAR more experienced with this than I am. And it's in everything I've read as well.

While my "mechanics" may be a bit off, as near as I can figure it's simply more efficient and faster delivery of the fuel to the cylinders. Since my mixed up mind seems to operate better using analogies, I look at it like a bike ride. You can have 100 bikes on a 100 mile trip; if there are a lot of sharp corners on the ride (stock manifold), it might take 3 hours for all riders to complete the ride (fuel arriving in cylinder), but all bikes are going to get there, but some are going to take the curves slower, others faster. Now, if the path has some gentle curves (ported manifold), all 100 bikes are going to get there, just like on the sharp-angled ride, but they'll just get there faster and more likely at about the same time since they are unimpeded.

Anyway, that's how I break it down so I can grasp the concept...although I could still be totally wrong...

RK

Bru, read a pretty good explanation for it in roadstar magazine(?) that I found on the web. Went to the FAQ link and it was explained in there. Give it a shot.

The best explanation I found:

http://www.nopork.com/tech_PMfaq.asp?action=tips

At least I kinda, sorta, pretty much so, maybe just a little bit understand it.

http://roadstarclinic.com/content/view/52/96/

Musky wrote:
http://roadstarclinic.com/content/view/52/96/

I guess bru thinks the other explanation is better.

Just joking with you bru.

Doc

I typed in "manifold porting" here on the clinic and didn't get that. Oh well, saves me some tinkering.

The folks that run the Clinic have put a lot of good info in the tech tips. I picked up a lot by just browsing around in there.

Now would be a good time to say thanks for doing that for us

See? Like I said...100 bikes... Although, I will admit that Gram's explanation has a lot more of those "fact" thingies in it...

And Musky is right--thanks again to everyone here for all the help you have given, and I'm sure will give me. I refer to you guys more than the service manual...and usually after I refer to the service manual...

RK