I'm currently rebuilding my engine and wanted to port it while I'm at it.

The car will be a track car only and will be driven on the street only on highway runs to the track.

I don't want to over do the porting though because I will stay stock twin sequential for the moment, but will very likely go single some day. Other mods are listed in the signature.

Unfortunately I have a problem most of you don't have: Im located in Germany, so getting hold of most of the available templates is either very expensive or not possible at all. (For example, Pineapple Racing is charging $47.30 for shipping to Germany, the actual template is $45, plus 30% taxes and duty on the product price AND the shipping)

So I was wondering if there are digital templates that I could transfer on to a sheet metal myself or if anyone located in Europe could recommend something.

If you can't help me with my supply problem, please recommend me a suitable template anyway, I will try to get hold of one if there is no other way.

 

Getting a local rotary shop to do it for you would probably be the simplest solution. I would advise against doing it without practicing on bad housings first. For...reasons.

 

Thats definitley no option for me. First, there is no shop around that I trust, second there's the costs.

 

Leave it stock then. It will be way more expensive if you mess it up.

Save the money and get a better turbo. Stock ports aren't bad.

 

Why is everybody assuming that I mess it up?

I will try not to, can we move on now?

 

just an idea why dont you contact your nearest reputable rotary shop and ask them, might cut some of the shipping cost out

 

I'm not assuming you will mess it up. I'm just saying that if you can't afford to pay for a template or to pay someone to port it, you will be in a heap of trouble if you do mess it up. Inexperience porting can lead to a lot of issues. At least practice on something first if you must do it.

Since the car is close to stock, I'd just spend your time on further reliability mods as they will save you money in the long run. Porting it won't be a game changer or anything. Save up and do single turbo on stock ports, nothing wrong with that.

 

Seriously? The man is just asking for the most appropriate template. If you don't have an opinion that is germane to the question then leave him alone.

Namxi: I've used Pineapple Racing templates in the past and have been happy. I've started slowly revising them and combining traits from their template with a local racers templates however.

 

The stock turbos are a big restriction. When we talk about porting, most people think about flow, but really the most important thing here is port timing, similar to valve timing on a piston engine.

Here's what you really need on stock twins. You just want to close the intake port a bit later and clean up (polish & smooth) the port. This increases the duration of the intake event for better top end power, with limited effect on low end torque. Any modification to the exhaust I don't recommend in your situation. You just increase overlap. For that reason I wouldn't alter the intake opening timing either.

This recommendation is the equivalent of a Honda hitting VTEC. The intake duration and lift increases, the closing timing is later, but the intake opening event is unchanged and so is the exhaust.

That being said, easiest thing to do is buy a mild intake port (RacingBeat) and leave the exhaust alone. If you port only the secondary ports it would hardly affect your low end torque.

Porting Template for Streetable Intake 12A & 13B - Racing Beat

I realize this is a very mild suggestion, but since you are in Germany I'm guessing this isn't drag racing at all and you care about a usable torque band, spool, off throttle/on throttle response. Adding a ton of overlap with big early opening primary intake ports and big exhaust ports isn't going to help that.

 

Thank you guys very much!

 

Maybe you can't read, he said he doesn't want to pay for the pineapple template.

 

If you don't want to use a template at all, which seems risky and ambitious for a beginner, look at before and after pics of ported secondary intake ports. Mark a larger edge on the closing side, and then cut with a die grinder. That's the lowest risk way to do it.

You could port match the exhaust to the sleeves, but your exhaust opening timing will be earlier and your total overlap volume will increase. That's going to hurt low end torque and off boost performance with insufficient top end benefit IMO.

I know people port the exhaust on stock twins all the time, but that's just my .02 cents

 

I most certainly can read, which is why I addressed his concerns with shipping by mentioning that I've used Pineapple's templates in the past and been very happy. As stated, if you don't have an opinion that is germane to the question best bet would be to be respectful and not harp on the dude.

 

Honestly, the best thing to do would be to just pay the $120 for the template. The tools alone will cost that much if you don't already have them. This is also considering shops in Germany will probably charge 3-4 times that to do it for you (they charge even more in Japan). It's a tiny cost compared to the cost of the rebuild.

I wouldn't personally recommend Mazdatrix's templates, simply because you have to grind the template out yourself. If you don't do that part perfectly, you are going to ruin your irons.

Ask me how I know this. Actually, don't...

I am assuming PR's are already cut out.

 

Yeah, was going to say it would probably cost at least $45 to have it laser cut from a pdf, if you bought it online - not worth the hassle.
Could try some AUS/NZ shops for shipping, see if its any better ; Turbo Extend Porting Template

 

I just talked to someone here on the forums who has 340rwhp at 10psi boost.

The mods: PORTING and stock mount IC, full exhaust, 850 primary fuel injectors and secondaries drilled to 1300, Power FC and HKS twin power.

Unfortunately the porting was done many years ago by himself and he has no pictures of it.

As I'm going to run the car on track only, low end torque is not that important to me. To make that much power on stock boost is pretty tempting. Can anyone imagine, how a port that does this should look like? Or is there any source I could research this matter myself?

 

Sorry wrong thread.. Not sure how that happened

 

unless its a drag car or you want a ton of power, just say no to porting. keep it reliable and drivable. if you want more power, free up intake/exhaust and add boost.

i went the opposite direction and actually running smaller ports than oem, using a cosmo center iron. torque for days and still making 300whp at 10psi, and thats on a 3" cat too

 

It will be a racecar and driveability on the road plays a minor part. But what do you refer to when talking about driveability?

And where does the assumption come from, that with big ports there is no power increase? Some even say there will be a decrease.. The guy I spoke to proved that black is white..

My point is the following: If I can get more power WITHOUT raising boost, I call it a win / win situation. Less stress on the parts, especially the turbos, less heat... And best of all, its for free!

 

big ports making more power assumes that the stock ports are not already optimal, which is incorrect.

the stock ports are actually very well optimized not only for the power level, but also for a set of turbos with relatively high back pressure. if you port the engine you increase its net flow capability, but you also increase its sensitivity to backpressure. Mazda has an extreme example in the 'rotary engine' book, there is a graph of ve vs exhaust backpressure for a PP and a stock port, and with more than 1-2 psi of backpressure, you make more power with the stock engine.

or if you like, the turbo is the restriction in flow in the first place, and with a big port, its more of a restriction.

if you want more power at the same boost, you'd be better off with a bigger turbo

and its not free if you need to spend $120 on a template...