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-   Rotary Engine Building, Porting & Swaps (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/)
-   -   P-port runner angle (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/p-port-runner-angle-62676/)

Stanello 11-11-2006 09:00 PM

What are the benefits/drawbacks for different angles of the runner? MFR ones are parallel to the ground (if I remember correctly), while RBs come in at an angle:



https://i89.photobucket.com/albums/k205/stanello/rb.jpg



I would imagine that parallel to the ground would be optimal, but I don't think RB would do their housings that way without a good reason or two.

RotaryVillain 11-12-2006 09:19 AM

well MFR housings are like 1500/each RB made those just cuz they were cheaper i think the angle is just because they take a stock housing and just drill out the hole where theres already a small circle cast into the housing. i'm pretty sure the true MFR housings do make more power but they cost big $$$ like i said

just call Racing Beat and ask them about these housings they will gladly give you all the info you desire and more https://www.nopistons.com/forums/pub...IR#>/bigok.gif and they can give you info on the MFR housings which they also sell.

i've bought parts and had quite a few engine services done their and have had the pleasure to talk with Jim Tanner one of the coowners. Very knowledgable and personable guy. If you're REALLY lucky you may get Jim Mederer on the phone but i dont think he likes to talk to people he's too busy building crazy engines and cars from what i heard https://www.nopistons.com/forums/pub...IR#>/boink.gif

C. Ludwig 11-12-2006 01:18 PM


Originally Posted by RotaryVillain' post='844951' date='Nov 12 2006, 10:19 AM

well MFR housings are like 1500/each RB made those just cuz they were cheaper i think the angle is just because they take a stock housing and just drill out the hole where theres already a small circle cast into the housing. i'm pretty sure the true MFR housings do make more power but they cost big $$$ like i said

just call Racing Beat and ask them about these housings they will gladly give you all the info you desire and more https://www.nopistons.com/forums/pub...IR#>/bigok.gif and they can give you info on the MFR housings which they also sell.

i've bought parts and had quite a few engine services done their and have had the pleasure to talk with Jim Tanner one of the coowners. Very knowledgable and personable guy. If you're REALLY lucky you may get Jim Mederer on the phone but i dont think he likes to talk to people he's too busy building crazy engines and cars from what i heard https://www.nopistons.com/forums/pub...IR#>/boink.gif





I got Jim on the phone one day. He was very helpful and seemed to not mind spending the time talking. https://www.nopistons.com/forums/pub...IR#>/smile.gif

Tom93R1 11-13-2006 09:18 AM

The Speedsource guys at sevenstock were talking about that. They said Racing Beat goes in at an angle because its easier to make that way. They thought you could get a couple HP more out of the horizontal inlets but it wasnt enough to warrant the cost.

j9fd3s 11-14-2006 01:08 PM


Originally Posted by C. Ludwig' post='844968' date='Nov 12 2006, 11:18 AM

I got Jim on the phone one day. He was very helpful and seemed to not mind spending the time talking. https://www.nopistons.com/forums/pub...IR#>/smile.gif



yeah, we cornered jim too, he's really nice, sounds just like the catalog too https://www.nopistons.com/forums/pub...IR#>/smile.gif

C. Ludwig 11-14-2006 02:18 PM

On the housings I made, which were intended for a turbo app, I angled the entry to provide more clearance for the turbo assembly. I really don't think it would of been any harder to bore the hole straight. Wondering, since RB offers these is turbo and NA types, if they thought along the same lines as I did (clearance) and for simplicity sake (jigs, sleeves, process, etc.) build both types of housings the same way.

Stanello 11-14-2006 06:58 PM

Thanks for the input guys. I still need to figure out what I will be running as an intake mani before I decide on any certain angle.



I will more than likely have a machine shop do the housings. I thought about rigging something up like Scalliwag did on the other forum... but I dont have a lathe, and thats the end of that idea. Although a very crude method involving a vice and a drill came to mind...



Would I have any heat/warping issues if I welded a flange onto the sleeve after it was pressed into the housing?

maz_side 11-16-2006 03:38 PM

why weld a flange onto the sleeve if you dont have access to a lathe get a machine shop to turn up a sleeve out of solid aluminum bar and turn the flange on at the same time alot easier and more tidy have them bore the hole in the housing at the same time using a boreing head in a milling machine i would bore the hole in the housing first then measure the hole using a internal micrometer that way u can make the sleeve about 1 thou bigger and have a interference fit put the sleeve in the frezzer and warm the housing slightly not to hot and the sleeve will drop straight in and when it all comes back to normal temperature the sleeve will be in there solid.

crispeed 11-17-2006 02:38 AM


Originally Posted by Tom93R1' post='845063' date='Nov 13 2006, 07:18 AM

They thought you could get a couple HP more out of the horizontal inlets but it wasnt enough to warrant the cost.



That's funny especially comming from where cost vs horsepower gain has no limits! https://www.nopistons.com/forums/pub...IR#>/smile.gif

Since when in racing is power not worth the gain. Read between the lines. https://www.nopistons.com/forums/pub...IR#>/smile.gif

Personaly I've never seen the angled PP housing make more power than a straight one of the same ID and port timing in a NA application.


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