pretty much

 

You want the exhaust manifold to be bigger than the exhaust port on the head. To prevent the exhaust pulse from going back into cylinder. Intake manifold you want to be the same size.

 

Interesting discussion. Second Chance do you have any credentials to back up your statement or are you just armchair tuning here? I'm not trying to take anything away from you just curious. It would seem to me that your statement makes sense.

Josh

 

^hes right, its called reversion and its not good, its not as much of a issue with the twin scroll, but i think you will be ok man.

 

Yes, sorry but you ruined a good exhaust manifold and porting the head isn't going to help, nobody in their right mind is going to ruin that to match the manifold.

 

guess its good I have another, maybe I'll try both

 

Do yourself a favor and get one of Buschur's first, then if you still want to experiment I would look on the forums and ebay for cheap stock manifolds and keep working at it. Wear safety glasses and a dust mask. having cast iron slivers removed from ones eyes is not a great time and the cast iron dust is hell on the lungs. I got my exhaust manifold and stainless o2 jet hot coated from David, I could have ported the manifold and built the O2 but know it works for the HP level I'm looking for and it gave me the time to do the develop the intake that I have posted on evom. Good Luck and keep trying, everyone started somewhere. Indy

 

Sorry Buschur and PPI but I am going to have to disagree. Granted port matching is not as good as perfectly matching it to the head but I haven't seen a loss comparing a port match to a perfect head match. Most people who gasket match only go so far and due to the amount of volume the air isn't bouncing off the walls like you guys think. He took away the turbulence from the beginning of the manifold but only an inch, at the most two.

 

RevMoto, you can disagree, it is your right to do that. It is my right to make big power and go fast.

 

And the power God has spoken

 

What I am saying is he didn't ruin it. I know which way you port and I port the same way.

 

Egotistical much?




Oh and let me know when you figure out how to save a base map on a v1 accessport.

 

Nothing drastic has been done here to make your car blow up. But you did however go a little overboard. Look into maybe getting another manifold and trying matching it a little better this time. You can imagine though with that airflow and volume how much inconsistency that little mismatch can make. It really can but no, your cars not gonna blow up.

James

 

You guys re making it seem worse then the stock manifold. Stock is smaller than the head port so instead of having the air coming out and hit a wall in its path he took that out. Yes it made a wider path but that is less of a restriction then stock. It is clear that a port match manifold will make the same to a little more then a gasket matched manifold. I have done 6 cars to test it compared to stock and they all made power. I have done even more that are matched directly to the head and it was about the same. Difference is it costs more if you are doing it yourself to port match it then gasket match. David you are completely forgetting that this is a hobby and not so much a business. Many people on here love working on their cars and aren't going to going to come to you because you think everyone should.

PPI I am sure you do great work but telling somebody on here that they ****ed up a manifold and should have given it to you is just bad business. You offered no constructive criticism. This isn't the first time you have done this. You talk big but yet you have never shown any gains or proved that what you do is adequate to power then cosmetic. Saying you have so much experience says nothing to me and many members on this forum.

 

revmoto, I have done testing to, as you know. I don't care if he comes to me with the manifold and I don't think EVERYONE should come to me as you said. I simply said the manifold is messed up now. It will not flow as well as it would if it was port matched to the head. You can argue with me if you like but I think you just said the same thing.

Maybe I should have just said it looked awesome so everyone ports them like that?