Porting for idiots

[Jimi_Hendrix]

I just found out about porting the rotarys. Was looking on YouTube and keept seing these great vids of RX7s idling like lumpy race tuned V8s! Lol! All of them had this "half port" and "Street port" terms hanging around. I tried searching on here but didnt come up with any definitave explination.
 
Is it just the same as a Port polish on a regular cycle engine? And whats the diff betweeen this street port, half port and full port etc etc.?
 
Also whats all this about needing a bigger turbo when you do it?
 
I\'ve got a 13B 1990 FC3S Turbo II, daily driver come weekend track attacker. Is it recomender for that type of application? And does it kill reliability?
 
And i guess finaly (sorry for all these n00b questions Lol!) what kind of power gain do get? Seing as it costs abot 500 quid i\'d like to know what that nets ya. Lol!
 
Cheers! I\'m just lovin\' that lumpy bwap bwap bwap bwap idle!:Giggle

[BlitzBoy]

dont think you have searched properly as there is loads of info on here .
Anyways read this link
http://www.turborx7.com/porting.htm
info on there.
Stick to a mild street port any larger and you have to go bigger turbo as your stock turbo will be to small and overspool and sh&t its bed

[Jimi_Hendrix]

Thanks Blitz boy, was struggling to find decent definitions of the differances between all these portings. Does the mild street port still give you that lumpy idle sound?
 
Yes i know i sound like a bit of a chav but i love that sound!.:rolleyes: Lol.

[BlitzBoy]

The more aggressive the porting the more overlap you have at idle hence the brap sound, depends who does your porting, Era who built my engine makes a lovely braap sound but your economy goes down the drain as its a half bridge, and aggressive street port will do it as well, A mild one you be hard to notice

[Timmy]

Also to point out that normaly £500 on top of removing the engine open it up and change some seals and gaskets. Normaly done when rebuilding the engine.

[BlitzBoy]

Timmy I coundnt resist
TIMMY TIMMY sorry in a silly mood, be great avatar as you havent got one lol

[sadgoth]

oi you with the facial fungus, get back to the point

As blitzboy has said to get a decent brap brap sound you need some fairly extreme porting and your fuel economy REALLY suffers! I worked out the economy I was getting on average the week before last in on combined town and A road driving and I managed about 5-6mpg!

[bnaellis]

you can get a really good brap brap with minor porting and overfueling as well.


rgds

Brian

[AshRX]

some porters can actually make the same amount of power out of a very large street port compared to a half bridge now

[dthebuk]

some porters can actually make the same amount of power out of a very large street port compared to a half bridge now

is that through brilliant tuning or actually really well designed ports?

just curious

[BlitzBoy]

both tuning and porting

[Jimi_Hendrix]

So how does all this affect the engines general health and well being with regards to reliabuility?
 
Thanks for all the info by the way.:Thumbs-up

[sadgoth]

shortens the engine life - (more power normally means less reliability) but good tuning should mean that you don\'t suffer too much on the reliability side

[trotter]

The more aggressive the porting the more overlap you have at idle hence the brap sound, depends who does your porting, Era who built my engine makes a lovely braap sound but your economy goes down the drain as its a half bridge, and aggressive street port will do it as well, A mild one you be hard to notice

Does anyone else find this bit a wee bittie ironic? Anything with 13b in the title will do this quite effectively!!  :Laugh :Laugh