I have a few questions
What do they do?
Are they needed.
Do you remove them to enlarge the port and put them back?
How do you remove them?
What happens if you run the engine without them?
Ant I remember reading about Ross removing the exhaust sleeves on his drag car. Alot of hard work but worth it. See if I can find the thread:cool
That would be useful, cheers
if they are some sort of heat protection then 10 seconds at a time would be ok but what about 45 minute stints on the track?
I think most of it is to do with cutting some of the noise down. There are some really interesting threads to do with Paul Yaw and other people making some better shaped diffuser inserts and making some interesting gains on rx-7 club .com . Remember ... a larger port does not always flow better than a smaller one of the correct shape ooooer :D
Cant seem to find the thread I want.:2Confused
Carl says:
Keep the inserts,they aid heat transfer to the exhaust manifold
in this here thread tho
http://www.mazdarotaryclub.com/forums/showthread.php?t=22662&highlight=remove+exhaust+port
They also help exhaust flow as this leaves the rotor housing. Dont need to remove them unless the exhaust porting is very large. From what I\'ve read, hp gains get pretty small above a certain level of exhaust port enlarging. As Mike said, its important to get shape correct. A flow bench is the best tool to have for serious porting work as described in the yaw power website.
Ive removed mine on my fc drag engine, mine are fd rotor housings though.
Theres a small dowel holding them in, just drill or cut the small dowel out with a small porting tool and they pull out.
I read somewhere a while back the inserts are to aid heat transfer and reduce noise.
Tims done it on his 12a drag car, he told me how to do mine.
You can go a lot bigger with your exahust ports up and down once they are removed.
i will have a look and see how much bigger i can with them in.
Hi Ant,
I have a high spec heavily ported knightsports engine, they have not removed the inserts, but they have done a lot of modification to them.....I believe there is a compromise as people have stated with temperature