Dragon

anyone got any there willing to share?

HWO

you can mark bridge ports out yourself

simply follow this pic

the inner red line is the oil seal tracing line
the outer red line is where the rotor housing sits
the top blue lines is 10mm above the top of the factory secondary port
the outter purple is equal with where the housing sits
the inner of the purple is 5mm beyond the outter edge of the factory port

the green strip should be 5mm wide all the way

simply mark out and do one of your secondary ports then make a template of it and replicate it onto the other plates

David Hu$tlerhoff

thx for this useful hints HWO

Node

iTrader: (1)

thanks HWO

Grizzly

HWO i have a questions for you.

Basicly do you make the big port first only taking the wide bit back 10mm not doing anything else then make the second slot parallel leaving a 5mm gap between (is that minimum?) and do i leave it set back abit from the thinist end of the orignal port? then take it level to the wide end

Also will i need to take some out of the Rotor housing for it all to work? and do i need to do all my inlets or can i leave my primarys (o and which are primarys and secondrys?)

Thanks.....Chris

Grizzly

Just making sure before i mess up my engine. lol

HWO

the primary ports the the two in the centre plate, the secondaries are the ports in either end plate.

it sounds like you just want to run Secondary bridge ports and you dont want to go down too low, if you car was just a race car i'd say go down to be level with the bottom aswell, this means the ports are opening earlier. if you just take the bottom of the bridged part of the port down to around 15-20mm above the bottom of the normal port, it should be enough to give you significant gains.

if you wanna learn more talk to either Crispeed or RICE RACING as they are the ones who i learned most of what i know from.

Grizzly

Yeh i have decided to build a Partial Bridge Engine. I will Street port the Primerys and Bridge the Seconderys.

Am i correct in saying on tickover the secondrys are shut so there is no flow through the Bridge?

Thanks for all the help u realy know your stuff

HWO

there is a trace of flow thru the bridged ports cause the TB doesn't seal vacuum proof.

I know some of my stuff, i am doing my best to learn the rest

Grizzly

Does this picture look a good Bridge.

The main port looks wider than my std port, It looks like the main port has been opened up (towards the water seal) then the Bridge has been done. But will that cause Corner tip problems?

Thanks

Grizzly

That is'nt my engine, i would love to see it looking like that.

I have just started porting my plates, i am doing my Primarys first (center plates) they are going to be Street ported or as close as i can, basicly all i have done is cut the large end back 10mm and ported the inlet. Is this right?

Then i am going to make my Seconderys look like that picture. Take the big end back 10mm and cut a slot parralel that finishes 15mm from the small end. No probs

What would you say is a good size for the atual inlet on the plate? or is it a case of matching the manifold to the inlet and then keep it all the same size to the Port or is there a maximum and minimum size.

I see why its easyer to get someone else to do it but when the car is pulling 11sec 1/4 i can say i built that. LOL

Chris

WackyRotary

That bridge looks pretty normal in width compared to mine.... You want like 5mm thickness there. Going below that makes the likely hood of engine failure more possible...

HWO

You have to taper it up to the top lines, you cant just 'cut' straight in if that makes any sense

yes that bridge looks ok, they have gone beyond the edge of the rotor housing, if you go that far you need to grind a bit off the edge of the housing to make it flow to its true potential

Grizzly

Sorry to keep going on about thes Bridges but when you are doing it your self and its your first Bridge i just want it clear in my mind exactly what i am doing.

Right so the atual position of the Bridge, can i open up the main port (towards the water seal) any, or is the 10mm cut from the wide end as much as u can do to the main port?. Then there is the Bridge its self, is 5mm the minimum width of the Bridge so i can make it slightly wider and cut the new port so it is under the Housing (with a cut out in the housing) just for safety and how thick can i take the Bridge down to?. Is there a limit to how close to the water seal i get with my new port or is it a case of leaving enough so the seal does'nt fall out?

Back to the Street port, can i make the port wider (ie closer to the water seal)? or can i only work on the wide end?

Thanks for all your help i realy could not have done this with out you.

And i bet you are geting tyred of Bridge questions.

Grizzly

When you say "i have to taper it" do you mean the big end of the port?

Thanks.......Chris

peejay

I think he means like this:

http://personal.riverusers.com/~yawpower/pic5.html

Note that the top (closing) edge of the port is much higher up than the roof of the port runner... also note that this is a pretty huge port!

HWO

On the street port (god i hate that term, its a GAY) ie: An EXTENDED PORT you can go outwards with the stock port a bit. basically you can take the egde of the secondaries out 1.2mm (playing it safe. then you make a template and port the primaries to have the same back edge.

I cant really be bothered sitting here and typing out a great long essay about how to port where rady rady rady, if you understand the basic physics of a rotary engine, the cam durations etc and the effect they have on a piston engine then you should be able to combine the two and figure it all out, keeping in mind you have to keep bits there for the side seals to run on.

On a bridge port there is no point in taking the outter edge of the main port outwards towards the water jacket, all you would achieve is a thinner eye brow part of the port which would flow less.

Grizzly

Thanks for your time, I'll have a go and see how much damage i can cause.LOL

Chris

87GTR

iTrader: (61)

Grizzly: how did your bport turn out you have any pics of your ports?

im going to enteded porting my primarys and bporting the secondards in a few weeks.

RETed

You might want to include a disclaimer that that housing is a pre-FC3S side housing, and with that "large" of a BP, you need to cut the water jacket o-ring and seal up some coolant passages since the BP actually sits in the water jacket o-ring grooves (which is in the rotor housings for these erly engines)...


-Ted