i was looking at stuff i need for my car, and i was looking at porting templates from mazdatrix, and for they're exhaust template, they have a street port, and a race port. does anyone have any experience with these, or anyone who knows the difference, your help would be appreciated.

also, for anyone else, what porting templates do/have you guys used

heres the link. http://www.mazdatrix.com/toolport.htm


edit again. rb has the same thing, a street and a race, only cheaper. but for rb, i cant find the seperate intake, could someone put me on the right path?

 

I think the SP is sized to go with a SP intake port and the race port for a BP or PP. Not sure though. Id call and ask.

 

If you ever plan on going turbo or using N20 then get the race exhaust port. If you're going to stay n/a then get the street.

 

i do plan on going turbo. so if i go with mazdatrix, i should get the race exhaust, and the street intake, right? but what about with rb i couldnt find an intake template, are theres paired maybe? cause if they are, then RB is alot cheaper.

 

um, both the RB and the Mazdatrix templates are the same.,

(This is Chuck from Indiana. ...)
You are welcome to borrow one of my templates.

Oh, and if you are going turbo, you are better off with the smaller street port, rather than the race port.

If you think about it, your smaller exhaust port will have a higher=pressure exhaust pulse... than a larger hole, therefore it will spool the turbo quicker...
this only works to point... if you plan to build an engine with a huge turbo, that is not very streetable, a larger hole would work better...

Lots of factors here.

 

Street will open only as big as the steel sleeve will allow. Race will remove the sleeve and open even more.

You dont need an exhuast template, just open the exhaust as much as you can to the sleeves keeping everything even and smooth ! ! !

 

Yeah, ^ what he said. I didn't use a template on my exhaust. Just port it until all the sides are flush with the sleeve. I didn't think their race template would have you remove the sleeve.

 

i don't usually like to port up to the top pf the sleeve, you are a better off, only going about about 1/4" (which I guess is pretty much there anyway, keep the top of the port as flat as possible, then cut and blend a bevel at the top. going up on the exhaust,gives you greater overlap. I would rather go down a bit on the intake, than up on the exhaust.

the sides should be about 1/2" from the side of the housing itself. then i port down and round the bottom of the port, bevel, and blend the bottom and sides so it looks like a semi-circle. this is an effective port on a turbo application as well as N/A because the rounding on the bottom of the port causes the exhaust pulse to begin at a high pressure, then continue to open until the cycle is complete.


I have some ideas I want to try, basicaly building on things i have read from some really really great porters out there. I'll be porting/assembling my 12A next week, going for 200 RWHP. (If I end up with more, that would be fine with me)
I'll keep you guys posted if you like.

 

Just going up to the top of the sleeve doesn't give you much overlap at all. As long as you don't touch the bottom or inside edge of the intake port(which you shouldn't do anyway). Also, on the intake port spin the rotor on top of it and mark where the side seal passes it on the closing edge. Cut a bigger bevel, or a small notch, there than on the rest of the edges of the intake port. That way even the the port is very large and the side seal isn't quite supported enough and drops into the port a bit, it won't break the seal because it will have a nice slope to ride up instead of hitting the hard edge on the port and breaking.

 

For some real expert stuff on exhaust porting read up on Judge Itosan's posts on nopistions, also check out www.yawpower.com . Theres alot more to this than you guys think. If you have access to a flowbench you will learn ALOT if you use it.