Wanted: Templates for Half Bridge Port

[antnicuk]

I\'m gonna build myself a spare engine for the TII, i\'m gonna stick with the TII engine cos i\'d like to keep the car true to its roots.........  oh yea, and i\'m tight! (read Poor)

My current set up is \'big\' enough to take more power (fuel,exhaust,fmic, WI etc) so i thought while building it i will have a go at a half bridge.  I need some templates to do it though.  

If i dont like it i will be quite happy to put my current set up (streetported)back as its great and 460 bhp with very little lag is still good power :Thumbs-up

I know i could get more power with a newer RE or REW engine and a T51 but i fancy having a play with some porting

[kazisdaman]

You may try contacing Pineapple Racing, I believe they are selling porting templates now. http://www.pineappleracing.com, you can easily just email them.

[Iwan]

You can make one by hand.

get your Rotor in to Position of where the secondary will open, mark the place where the Rotorface will starts open the port up to the rotorhousing. This is the Point to stop but you can go + 5mm more to the exhaust-port side. Mark about 7mm from the secondary port into the direction of water grouve. Mark about 2mm from the water grouve. Drill a hole and port the remaining space (between 7mm from the secondary port and 2mm from the water grouve) in abou 45° into direction of intake but keep the Bridge straight with the side to the port.

I would recommend you to take your housings to any of the workshops and pay for the job (it takes hours to make it!)

Hope this hels.

[kazisdaman]

If your engine is already dissassembled, then it should be fairly cheap to have a shop do it also. because they would not have to tear apart the engine.

[interloper393]

giv grizzly a pm, he has templates plus he`s done a few cn give you some how to`s and advice.. lol he`s a very nice man

[Grizzly]

Done a few? I\'m not an expert on Bridges but they are easy to cut.

I did have a RE Half bridge for a Big and they do like to spool Big Turbos But i\'m sure you know all about how Bridges run.

Easyest way to do it is to Mat black the Port area then fit the E-shaft,Rotor etc and fit a Corner seal. Then run the Rotor round the Port Area which will scratch off the Matt black. Now the Trick is just to clean up the Corner seal edge of the Stock port leaving as much meat on as poss, Now you will have a good idea how wide the Corner seal Track can be, Mine was supported 70% so if you now mark out 2-3mm away from the Water seal groove then your half way there. Now come the risky bit, You have to determine how big the Aux Port can be before you hit the Water ways, i personally stuck my fingure into the Runner and marked roughly where the port wall was, then you have to cut any more than that at an Angle mine was about 30deg if memory serves (just don\'t go mad because you will hit water).

This is the reason you will only get Templates that are Runner size if you bought a Big Bridge Template you\'d get Noobs going into the water ways all the time.

O yeh, i would suggest only trying to cut a Bridge if you have a Miller, I\'m fairly handy with a Die grinder and it is just not Practical (Takes a LONG!! time to do neatly) Its just easier to cut with a Miller then smooth in with a Grinder.

Just make sure you leave as much suporting the Corner seal as you can, Don\'t get to close to the Water ways, Don\'t take too much out of the Stock port (corner seal edge) and you should be ok without a Template.

[Grizzly]

BTW i\'ve got a Big extended port Template i can Photo copy or something?? if you wish? its got a Good size Primary but it was Done for an FD so i\'m not sure if it would be the same??

[interloper393]

got my eye on a to4e turbo, so guna do ma ports, whats the best one for power but less laggy griz?  was aiming for 400bhp.. entended or street?

[Grizzly]

entended or street?

LOL one and the same...

[Grizzly]

got my eye on a to4e turbo, so guna do ma ports, whats the best one for power but less laggy griz?  was aiming for 400bhp.. entended or street?

As i was once told, Its more about the Flow of the runners than the port, If you look at it in Boinger Terms, If you flow the Runners well its like fitting a Gass flowed head, if you Change the port shape its like fitting a Bigger cam (the More radical the Shape the bigger the cam)

If you want Good street, Small Ports with Good runners.

If you want Power, Good runners with Big Ports (But if you have Big Ports you have to spend more time on the Runners becouse Big ports/Runners cause Low Air speed off Boost and Low Vac, on a Bridge you will notice the Brake servo will play up and need an assist Tank) And all thats before you get into the Effects of Overlap.

[Carl]

You have to be very careful in making a reliable bridge port,as there is more to consider than just the corner seals,the leading edge of the side seals is critical too.The amount of bridge both rubbing surface and depth are also important.
Regards
Carl

[Grizzly]

Is\'nt the side seal more to do with the Origanal Port? If you go larger you have to take into account the Side seal flex etc (basicly the corner catching the Closing edge of the Port) Don\'t you just finish the closing edge with a Chamfer? (Aux port too oviously)

The same sort of rules aply where its a Bridge or Big Extended port.

[TwistedHumour]

I know what porting is/does.  But still a bit confused on the whole concept.

Is there any recommended reading on the subject that I can get from amazon or the like?

Cheers

[Prof]

The book by Mike Ancas isn\'t bad if your after a book to read
 
http://www.amazon.ca/Mazda-Performance-Handbook-Mike-Ancas/dp/0760308020
 
There is also a good bit of info here :
 
http://www.mazdatrix.com/faq/porting.htm

[Carl]

Is\'nt the side seal more to do with the Origanal Port? If you go larger you have to take into account the Side seal flex etc (basicly the corner catching the Closing edge of the Port) Don\'t you just finish the closing edge with a Chamfer? (Aux port too oviously)

The same sort of rules aply where its a Bridge or Big Extended port.

The leading edge of the side seal must not have any area of port to catch on,it can and is very easy to do the port wrong and remove material that can wear it even if chamfered.whereas it is most important to make sure that the LEADING edge is supported through it\'s movement over the inlet port\'s bridge.
Regards
Carl