Ok, I'm swapping engines right now. I pulled the exhaust manifold off my old engine and I noticed these little fins in the exhaust ports. I looked at my new
(used) engine and someone ground them off, it just looks like two small welds in the bottom of the ports.

My question is: Why would someone do that? Is it common to do that when the motor has been ported?

I have no knowledge of the engines history (modded, overheated, etc...)

 

Some people grind the diffusers off to eliminate the "restriction". In reality, the diffusers aren't really much of a restriction at all. Mainly, they are there to control noise. All taking them off is going to do (assuming no other porting has been done) is make the car a little lounder.

On the other hand, most people take them out when porting. It can be hard to tell if an engine is ported. Clues would be a very smooth intake/exhaust runner. If you know the size of the stock ports, you can feel the ports in question and get a good idea of what was done. But since you are asking, I can assume you have not fingered many ports.

 

HA HA HA HA HAH AHHAAAHAHAHAHAHAHHAHAAHAHH AAA!!!!!!!

 

lol.

 

that quote is awesome Aaron!!! not fingering too many ports Eh!! .

 

You people need a hobby.

 

I do have one, its these damn cars. Its not our fault we all share a sick sense of humour!!!

 

lol. look whoes talking.

 

lol that was pretty good

 

Aaron has almost 8k posts, i think HE needs a hobby j/k bro, you goin to the rev this year?