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R.P.M. 10-20-08 01:28 PM

Recent porting pictures 56k death
 
Hey guys, I haven't done too many performance engine build's for a while now. Just stock port motors, I guess some people want to try and conserve fuel mileage lol.

Anyways, I ported a few engines recently and figured I'd post some pics.

First is a Full Bridgeport 13B REW. Its going to be run N/A in an FC racecar.

http://i256.photobucket.com/albums/h...e/DSCF3527.jpg

http://i256.photobucket.com/albums/h...e/DSCF3528.jpg

http://i256.photobucket.com/albums/h...e/DSCF3529.jpg

http://i256.photobucket.com/albums/h...e/DSCF3531.jpg

http://i256.photobucket.com/albums/h...e/DSCF3532.jpg

Notched housings

http://i256.photobucket.com/albums/h...e/DSCF3536.jpg

I have yet to port the exhaust housings, need to get a pair of T2 sleeves first.

Next engine if for an FD with an HKS T04Z turbo kit. We bought two new irons from Mazda and a used front iron that was in excellent shape.
The new irons have terrible castings!

http://i256.photobucket.com/albums/h...D/DSCF3540.jpg

http://i256.photobucket.com/albums/h...D/DSCF3542.jpg

http://i256.photobucket.com/albums/h...D/DSCF3550.jpg

http://i256.photobucket.com/albums/h...D/DSCF3560.jpg

http://i256.photobucket.com/albums/h...D/DSCF3561.jpg

http://i256.photobucket.com/albums/h...D/DSCF3562.jpg

R.P.M. 10-20-08 01:29 PM

This engine is for a 10ae FC. The irons were already ported, but they needed some touch up work and the new rotor housings needed porting.

http://i256.photobucket.com/albums/h...E/DSCF3494.jpg

http://i256.photobucket.com/albums/h...E/DSCF3495.jpg

http://i256.photobucket.com/albums/h...E/DSCF3499.jpg

http://i256.photobucket.com/albums/h...E/DSCF3502.jpg

I cant take credit for this porting, a buddy of mine did this set of housings for my All Motor FB drag car. I just need to fill in my irons with Devcon and assemble it....hopefully soon.

http://i256.photobucket.com/albums/h...B/DSCF3397.jpg

http://i256.photobucket.com/albums/h...B/DSCF3398.jpg

andre sinclair 10-20-08 01:43 PM

Nice Port Work (Bridge Port)

Gorilla RE 10-20-08 06:28 PM

Looks nice man....Though I would suggest back/under cutting the eyebrow more than you have done. More efficiant power to be made here, manly due to the more direct air flow from the runner to port opening. I know you may want to keep it "meaty" for the bridges longevity factor but NOT as much as you have currently. :icon_tup:

-J

RacerXtreme7 10-20-08 10:17 PM

^^ What he said. The finish work looks good, but theres quit a bit of lack of back cutting and blending on the opening portions of the ports and the bridge cuts them selves. Ports shouldn't be perpendicular to air flow or intake runners. Make it as smoooth and gentle transition as possible.

~Mike.............

R.P.M. 10-20-08 11:05 PM

Right on, great advice. I will try that on some junk irons I have to see how far I can cut the port back just before the bridge port.

I know what you mean about air flow to the ports, I try to give the bridge ports a slight angle towards the inlet of the port, not perpendicular to the port.

Gorilla RE 10-21-08 12:09 AM

Also concentrate on the eyebrow--port closing corner. There is much porting and reshaping to be done there. Try and keep the eyebrow thickness consistent even as it gets closer to the edges. The corner where the eyebrow meets the closing edge of the port is very important, it helps keep velocity through the port so as to give you the venturi/sucking effect we're looking for when the rotor is closing the port.



-J

mono4lamar 10-21-08 01:13 PM

There should be a 1-2mm bevel... I literally use sandpaper wrapped around a pencil.

RacerXtreme7 10-21-08 01:56 PM

The rotor housing exhaust ports have a bit too big bevel on them as well. Testing by Paul Yaw on both flow benches and engine dynos show over beveling hurts flow and power. I think the new concensous is 2~4mm bevel on the closing edge and sides, smooth the open edge and blend. Again, good finish wokr on the ports, just some more grinding, back cutting and blending.

WOW, those P-Port intakes are huge, and I assume the face will be ported rather then left round?

~Mike.............

R.P.M. 10-21-08 03:50 PM

The housings I ported actually have stock bevel on them at the top, I just made the side bevel match the factory top and rounded it slightly toward the port.
I'm going to give the closing edge of the intake ports a more noticeable bevel.

RacerXtreme7, what do you mean ported rather than left round for the PP housings?

diabolical1 10-21-08 04:43 PM

regarding your question ^. hopefully, i'm not speaking out of turn, but most full peripheral ports actually have a rectangular face, rather than round. i've only seen round faces on semi-peripherals.

i agree with all the constructive criticisms you've received so far, but overall, it's nice work. make sure to follow up with how these labors of love perform when they get going. keep it up!

R.P.M. 10-21-08 07:24 PM

Ahhh I see what you mean about the Peripheral Port, I'm going to leave them just the way they are. This same port is used in some very fast All Motor drag cars in PR.

Shainiac 10-21-08 08:14 PM

Aren't the MFR PP housings round? And the RBs?

RacerXtreme7 10-21-08 09:27 PM

diabolical got exactly what I was reffering to. And no, the RB and MFR don't have round port profiles, they are semi squared off.

~Mike..............

R.P.M. 10-21-08 09:45 PM

Stock ports have a sharp closing edge, not beveled or rounded. On the REW engine I ported, I hardly moved the closing edge, only slightly to match it up with the runner of the port. In the one picture above you can see what I ported on the primary port, I moved the opening edge closer to the water jacket. So I dont see the reason to bevel the closing edge.
On the bridge port and the "already ported" T2 engine the closing edge has been moved later compared to stock, so beveling the edge has been done, it just doesn't show up very well in the pics....must be my camera.

Gorilla RE 10-21-08 11:21 PM


Originally Posted by R.P.M. (Post 8657807)
Stock ports have a sharp closing edge, not beveled or rounded. On the REW engine I ported, I hardly moved the closing edge, only slightly to match it up with the runner of the port. In the one picture above you can see what I ported on the primary port, I moved the opening edge closer to the water jacket. So I dont see the reason to bevel the closing edge.
On the bridge port and the "already ported" T2 engine the closing edge has been moved later compared to stock, so beveling the edge has been done, it just doesn't show up very well in the pics....must be my camera.

IT IS SUPER IMPORTANT TO BEVEL THE CLOSING EDGE NO MATTER WHAT. The side seal has to pass over that at 8K rpm and if it's left "sharp" you will over wear the seal. The stock REW closing doesn't have a bevel because the port profile is made with a CNC machine for speed of production and never touched by a human hand (as it needs to be). It NEEDs to have a bevel on it.....Lynn Hanover used to say "if you can't pass your toung over it at 100mph than its to sharp". Funny yes, but the point is that when the side seal is closing the port like a pair of scissors at 8k rpm you DON't want it to sharp....for more than one reason.

-J

R.P.M. 10-21-08 11:35 PM

Ok so your saying that when its cut with a CNC mill and it leaves a sharp edge its fine....but when someone ports it by hand and moves the closing edge up 1mm it is totally different then the CNC port and will chew up side seals?

I suppose I should point out that I didn't leave a razor sharp edge on the closing edge...after smoothing the ports out with 120 grit sanding wheels, there is a slight rounded edge to the closing of the port.
I have used this style of port on a few Turbo'ed engines, leaving the closing edge stock, and they have been working great.

Gorilla RE 10-22-08 12:07 AM


Originally Posted by R.P.M. (Post 8658187)
Ok so your saying that when its cut with a CNC mill and it leaves a sharp edge its fine....but when someone ports it by hand and moves the closing edge up 1mm it is totally different then the CNC port and will chew up side seals?

I suppose I should point out that I didn't leave a razor sharp edge on the closing edge...after smoothing the ports out with 120 grit sanding wheels, there is a slight rounded edge to the closing of the port.
I have used this style of port on a few Turbo'ed engines, leaving the closing edge stock, and they have been working great.

NO...I'm saying the CNC edge SUCKS. I don't care who or what did the port, it needs to have a bevel on it.

Again, this is a forum so you can take what I say with a grain of sand if you want.....if leaving it stock has worked for you fine, do what you think to be best. But what I have said is as true and as good advise as any I can promise you that. Good luck with your porting.

-J

datsun1200 01-03-10 09:01 PM

http://i256.photobucket.com/albums/h...B/DSCF3398.jpg[/QUOTE]

Dam those port's on those 13bre iron's are big or are those stock????

Chuck Norris FB 01-03-10 10:40 PM


Originally Posted by datsun1200 (Post 9714486)

Dam those port's on those 13bre iron's are big or are those stock????[/QUOTE]


20b's and 13b-re port's on the Irons are that big in stock form, FD port's are a tad smaller and Fc are pretty dam small.

mike0615 04-07-10 04:41 AM

Does anyone in the west coast tune ported 13B REW engines yet?

diabolical1 04-08-10 12:43 PM


Originally Posted by mike0615 (Post 9919156)
Does anyone in the west coast tune ported 13B REW engines yet?

perhaps i'm missing something, but i'm not sure why you chose to ask that question at all, much less why you chose to ask it here, but ....

anyway, there are several tuners on the west coast. you're better off looking in your regional forum for specific tuners in your area, and you should provide information to include: what kinds of ports are you running and what engine management?


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