pvz018

Belive It Or Not I Have Seen A Lot Worse And Plenty Of Times . You Wouled Not Belive Some Of The **** I Have Seen.

ronbros3

Which is more important, the surface of the runner to the actual port,, or the port timing in relation to the rotor,, anybody??

__dave__

i built a fixture and flow testing will commence on monday

i'll try the stock port, 60 grit, 100 grit, 220 grit, and the golf ball divet finishes and see what there is to see as far as actual flow is concerned.

__dave__

while i'm thinking of these things, does anyone have any questions that might be able to be answered on the bench?

for starters, i'll be doing radiused vs. angled, and straight port closing edges.

closing edge angles (parallel and non-parallel to the rotor)

squarish top and bottom of the runners vs. round

also, i'll be cutting individual runners off a LIM and i'm going to attempt to balance them out. (fd)

if you have things you want answered, now is the time. the bench is really expensive to rent, so i'm going to have to have my gameplan together before i show up.

TonyD89

iTrader: (10)

Don't get the closing to parallel to the rotor edge. You need a scissor angle to help the trailing edge of the side seal back on the iron.

__dave__

not needed when the port closing edge is radiused. air flows better across a radius, compared to a dead 90* anyway.

rotarygod

iTrader: (1)

dave a radius in general does flow better but that doesn't always mean a bigger radius flows better still. On an exhaust port you'll find that a 1/8" radius flows better than a 1/4" radius. It's strange but the bench doesn't lie. Have fun with the flow bench. I've enjoyed mine.

__dave__

do you still have the plans for building one? the cheapest thing i've found so far is like $900ish.

rotarygod

iTrader: (1)

I looked up different homebuilt flowbench sites for mine. It's pretty easy to build. I don't think I spent more than $100 or so on it. There are different types of flowbenches. Mine is a pitot tube based system. Based on how much my manomoters (u-shaped vinyl tubing with water and red food coloring) move in inches, it is a set amount of pressure. There are 2 of these. The first one is to calibrate to the set pressure in the system. Typically I shoot for about 25" water but any level will work. The next manometer measures the force the air in the pipes is moving. Based on the amount it tells me I can figure that the air is moving at X mph through the system. Then from there it is just simple math to figure out how much air in cfm is moving through a pipe at X mph. Mine isn't complicated or terribly state of the art but it works. I have a little conversion wheel that tells how many mph air is moving at any level on the second manometer. The second conversion is done with a calculator. It's pretty easy and definitely not expensive. It works just fine.

Go searching on eBay or vacuum cleaner repair shops for vacuum motors. Get about a half a dozen of these so you can wire them up. I have a switch for each one so I can get close to the pressure I want by just turning them on or off. I also have a bleed off valve in the system that lets me dial it in perfect.

I don't remember where I found the plans but if I find the site again I'll link it for you.

__dave__

groovy.

i signed up here: http://www.tractorsport.com/cgi-bin/...gi?;act=SF;f=1

i should be able to get some decent homework done.

IGY

I don't see a problem with making the power on that octane. I ran 850/1680's to 90% with a static fuel pressure of 43.5psi and 11.0-11.2 AFR's running 20psi of boost on my secondary bridge motor using 88 octane(can you say run on). That was before I put in the water injection also. I can't give you any dyno #'s as it never saw one, but you can do the math from the specs I gave and figure out that it was well over 400whp.

diabolical1

iTrader: (3)

not trying to imply that i don't believe it because there's sure no reason to lie, but don't you guys have a different octane rating system over there?

KeloidJonesJr.

iTrader: (8)

tee hee porting with a chisel, makes me want to go buy a porto potty.

__dave__

the only debate i'm having with the power/octane/fuel economy is whether or not to use the 8.5 rotors, or the 9's.

with the 8.5's, no problem getting 400+ on 87 octane reliably, but i don't know how much fuel economy would suffer, compared to the 9's. if i do go for the 9's, i'll just work it up slowly and see where it stops. if i don't hit exactly 400, whoopity-******' doo! high 300's is just fine for that octane.

on a side note, the shop kinda pissed me off. they made me wait 'till monday, then i came over with 6 irons and they said to leave one and they'd call me in a few days to let me know when they were set up. blah!!!! so this is gonna take a shitload of time waiting for them.

nukeall

man i thought it was R&R Rotary ... are they good with what they do im taking my motor to them for porting now im paranoid :/

__dave__

na, that wasn't r&r.

Siraniko

iTrader: (13)

Paypal me some $$$ (not the forumdollars) and I wil tell ya.

__dave__

bleh.... the shop still hasn't got back to me yet. i dropped off the apparatus on monday. **** it, imma just build my own.

GUITARJUNKIE28

alright...another motor i just took apart.

anyone in socal wanna take responsibility for this one?

KeloidJonesJr.

iTrader: (8)

Port it for meeee!!!!