Porting an Engine?
 

Ok, quick question about porting an engine. I'm wanting to get some information before I plan on doing this.

First, what are the levels of porting? I know street and race I hear alot, what are the others, and which one is the biggest. Also, how much hp gain would you expect once you port an engine to one of those levels. And is it something I can have done to my engine, or would I need to buy a new engine to replace it. And what would be the cost of either of those options.

Thanks for the help

-matt

http://www.mazdatrix.com/faq/porting.htm
http://www.rotaryengineillustrated.c...-ports101.html

Check out the rest of Blakes site, http://www.rotaryengineillustrated.com , as well.

www.racingbeat.com

www.pineappleracing.com

Personally, it is easier to just pull off the intake manifold (upper) and port-match it. Use a Dremel and a grinding bit, use the gasket as a template, and grind away. Anything else will enatil pulling the engine, shipping the stuff to be ported, waiting, and spending an arm and a leg for 20 hp! But hey, I am a cheapskate, so mabye you should get another opnion!

Thats a mighty big can of worms you've just opened. I'm not even going to try to answer that but I'm sure some fo the more experienced rotor heads will have some more questions for you.

What are you planning on doing with the car? road race, autocross, dragrace, etc....

What kind of car? 1st gen, 2nd gen(turbo or n/a), 3rd gen

What intake are you planning on using? fuel injection, carb

Basically more information is a good thing. Tell us your plans.

Actually I don't really know what I plan on doing. That could all depend on what it costs and what gains I get. As of now I use the car as a daily driver, but want to drag it at the track occasionally. The car is an 89 TII with 150k miles on it. I am and will be running a fuel injection set up because I don't feel like dealing with carburator. I am thinking I might even want to go with getting a new engine anyway, just because of the high mileage.

in true rotary porting terms there is no such thing as a street port or a race port

You have stock ports
Mild ports
Extended ports - often called stage 2 porting
Bridge ports
J Ports
Monster ports
Peripeheral ports

those are listed from smalled to biggest - lowest HP to largest HP

a "street port" as you refer to it in the US is just a version of a mild port or extended port which is considered more "STREET"-able than a bridge port

I see.
So what would I most likely wanna do being that I will still be dirving this car on the street? I want the highest I can go with still being CA emmisions safe.

Depending on what part of the world you're from, people use different terminology.&nbsp But it basically comes down to several categories...

Street/extend/side port - this basically enlarges and extends the stock intake port

Bridge port - adds small port prior to the main intake port; a "bridge" is needed so the corner seal doesn't fall into the intake port (there are several variations on a BP: "J" bridge is one of them)

Peripheral port - blocks stock ports on the side irons and drills huge hole in the rotor housing itself

A BP or a PP is really unpractical on the street.&nbsp Others will try to argue otherwise...



-Ted

Go street port.
Any higher and you are only looking at power over 6000 RPM's, then you have to do something about your turbo (You know what your 150,000 mile turbo would do if you engine was spinning strongly at 10,000rpms??)
Also, you'd have to get race bearings, full balancing/clearancing. You'd have to do something serious about your intake manifold, (bottleneck at that level), a rebuilt water pump with a different impeller, plus, your engine life you be a lot less than a stock or mild street port. Not much difference in life with a mild port, becuase your redline is only bumped up by about 800 rpms (maybe a little more), but power is increased by about 15%. You do lose some low end torque though, but not enough to affect daily driving at all, barely noticable, maybe not at all with a turbo.
I think it's worth it- it bring you up to the next step- "climbing over the wall" that you can hit with flow on a stock engine.
Oh- porting does increase emmisions. another reason to keep it low.

I'm looking to get my engine rebuilt around the end of the summer. Figure I might as well get a mild street port, too. I talked to Dave at KD Rotary and he said that they did a fairly LARGE street port job on an NA FC w/2mm seals and turbo rotor housings. They dynoed it at 212RWHP. My main question is....After I get the rebuild and port job done, I was looking into the MD Racing Chip(Autocross Version), and the true dual system from Madzatrix(the $1400 one)....are these good choices? Thanks people....
Will
:withstupi

$1400US for an exhuast system - by christ thats insane
i can get a T04, Manifold, Wastegate, FMIC, 3 inch exhuast and all intercooler plumbing for that price

It'd gain you shitloads more HP too

Ok, sounds like a street port is what I'm gonna want. I'm gonna stretch it as far as it can go.

So now the question is, do I want to do this to my current engine, or do I want to just buy an engine with it done since I have such high miles? And how much would it cost to do either option?

Those are good choices for a rich ass man. But if you want the same gains but less money just buy the true-dual header, presilencers and whatever mufflers you want and have a shop do some piping for ya. That will save you at least $500 for the exhaust. The MD chip sounds good but I heard its not quite all its cracked up to be. I am not getting it because I want to run NOS later and can't have the timing increased for that. It prolly would be a good mod though.

wow. you sure fished this thread out of the deep.
and its actually got 70k miles, i dunno what I was thinking

From what I have gathered, porting does result in a loss of some low-end torque.