Porting template to use for streetable compromise
 

Target is for a street car. Spirit is to keep it smooth and very easy and comfortable to drive.
Currently it is full bolton stock port/twins 340whp. The clutch is on standard fly, dampered... I love it this way.
When rebuild will be required, I would like to make it breathe just a little bit more. But I don't want to lift the idle more than 850RPM, and I want to preserve the low end torque and reactivity on light throttle.

What kind of porting templates would match, on intake and exhaust side ?

For a little better flow without any change in driveability, I would suggest you look into ExtrudeHone intakes and matched engine porting. It's not a popular option around here as it doesn't result in a obvious change in the powerband that a street port would do. Here is RotorSports Racings web page on the subject. Your problem would be to figure out how to get the parts to a extrude honing and port matching shop here in the US and back to France without incurring large customs fees.

For better flow, a simple thing to check is the throttle body butterflys. I've noticed on many FDs now, pulling the throttle cable back all the way does not open the butterflys to their full 90 degree open position, probably due to wear of the cable linkage mechanisms. A few adjustments and replacement of worn parts will result in fully opening throttles.

Are you planning to use stock turbos or a small single? The engine can't breathe up top with stock turbos. I'm not going to say street port is worthless on stock turbos, but the stock ports are a streetable compromise already. If you have to rebuild the engine, just polish the ports and don't enlarge them (which changes the timing).

Yes, a single turbo capable of pushing 450whp (for rotary configuration) is what I think about. But I would probably use it to 16PSI, not much more. If I had a final target, It could be 300rwkW approx.

I went with a mild street port. No change in idle or low end driveability. It added about 20 hp, which was nice.

If moving to a single (which I would highly recommend over any configuration of the twins for no less than 489574846567 reasons), any mild to mid sized street port will be beneficial. If you still have an idle control valve and you have a capable ECU, you can tune most any mild to medium street port to a sub 800 rpm idle. I would focus on going to a single turbo setup instead of building the motor to change the port. You won't see a huge difference with the port change so it really isn't worth it unless the engine is coming out of the car and apart anyways.

Skeese

Keep stock ports but do a basic blue print.
Port match intake track from TB through block by opening them to match the metal gaskets. Smooth out all transitions and bad casting imperfections.
Even if the ports are stock, the machining of them is very rough with many bad spots. You smooth them out just like they do for porting. Especially where
the ports open up into the interior. Much poor machining.

You could keep the primary ports totally stock but increase the secondary ports closing edge. That is what Racing Beat 2nd ports do.
PineApple also increases the opening edge which increases overlap which is not good for street use.

Examine the TB, it can be improved!