Kyrasis6

Ok a couple of questions, I have been reading posts for the past couple of nights now and havn't found the exact information I'm looking for....

So far in a nutshell my plan is to do a NA build with a street port. The car at the moment will be driven occasionally on weekends and will see the roadcoars fairly often. For the exhaust ports I think I'll just do my own porting there without a template. I don't know what kind of timing to go for though, several "builders" on here say I should not go down on the exhaust port because it will reduce the power stroke. I honestly don't think advancing the port timing will hurt the power stroke all that much because most of the power is going to be made shortly after combustion (just my personal opinion). I don't want to go up all that much either because I don't want to increase my overlap.

So my plan for porting on the exhaust was going to be mainly to clean up the stock port, maybe widen it just a touch and open it a couple degrees sooner and close it maybe a few more degrees later.

My real dilema is the intake ports, I want to do a street port but don't know who's template I should use. Are they all pretty much the same? Who makes them with what timings?

I was also going to order some Pineapple inserts and do some slight touch up porting there. I do plan on running the car up to about 8,500-9,000 rpm possably but I don't want to adversly affect low end power that much (although I don't mind brap brap). In my other post to get input on my build a couple of people recommended porting the aux ports and using the TII sleeves. I have found posts on this regarding turbod cars where they removed the sleeves but I want to keep the aux ports functional so that they only affect power after they open and not at lower rpm. I'm pretty sure I would be happy with the results but do I just open up the port a little bit or do I cut a brow into it like on a bridgeport and then open up the sleeve behind it?

Any other additional input? I'll have about half my parts here by the end of the week and am wanting to order the last of my engine parts soon.

Thanks,
K6

Sideways7

iTrader: (7)

From what I remember reading, many people prefer going down on the exhaust porting (opening early). I dont have stock housings to compare to, but mine look like they went down and not up. Mine has the exhaust and a large street port (complete with brap - here is a link: http://mazdatrix.com/g2.htmhttp://vi...58001f0db8.htm) All of my intake ports are porterd, and it has no low end power issues at all. It actually feels quite strong all over the powerband, at least for an NA rotary. It made good power all the way to 7500 rpm, and that was on an s4 block so it had the lower compression rotors and s4 intake. I expect once I actually rebuild it using s5 intake and rotors it will make good power to 8500+.
As for templates, I'm not sure. I had mine proffesionally ported by Tito at Alamo Rotary, but I can post some pics of them if want to see them for comparison.
Edit: you don't want the Mazdatrix templates. For some reason they don't like street ports, so their templates are pretty consvative.

Kyrasis6

Yea, all the part I just ordered where from them, I didn't order the templates and some other stuff because I felt like I could get them better somewhere else.

What about the racing beat street port templates?

Sideways7

iTrader: (7)

I don't have any first hand experience with any templates, but I would assume that both Racing Beat's and Pineapple's templates would be goo. I doubt either of them would be truly maxed out, but I'm just basing that on marketing logic.
I attached pics of my ports.
Also, if you do any sort of cometition where your car is officially registered (auto-x for example) you can get a fairly substantial discount on mazda parts through www.mazdamotorsports.com All you have to do is send in 2 results a year.

Aaron Cake

iTrader: (1)

Using TII exhaust sleeves is pointless if you intend to port. During the porting you will be grinding out the NA exhaust diffuser anyway.

Moving the port down cuts into the power stroke, but spools a turbo much more quickly. Going up increases flow without cutting into the power stroke but causes overlap, thus reducing low end. It's always a compromise. Starting with a known good template is the best idea for a first port job. All the vendors have them.

The only 6 port template I know of is the Mazdatrix template. It's pretty conservative. It opens up the primary ports a lot, then opens the secondary and aux ports earlier. It does not close them later. Makes for a powerband close to stock, just more of it. When you start closing the aux ports a lot later you move your power band up. As does opening them much earlier (ie. bridge).

Kyrasis6

Sweet, just got a butt load of new parts in today, RX-8 eshaft with stationary gears and a few other small misc things.

A lot of people are recommending the Racing Beat porting template, I'm thinking about getting that and then just hand porting the Aux Ports.

Is it possable to do a bridge on the Aux port or would it cause too much of a dead spot in the power band when the primaries and secondarys give out? I do plan on having them actuated with an RPM switch.

This would be a lot easier to decide if I could drive a car that has had some port work done, lol.