|01-30-2013 10:45 AM|
You can use a coarse aluminum bit on iron all that will happen is a rougher surface finish from some chatter the wider flutes create, but they'll cut just fine. Aluminum will gum up the smoother fine iron flute almost instantly. You can kind of get away with the fine flute on aluminum if you frequently run the bit into a piece of bar bath soap. This lubricates the flutes preventing the aluminum from sticking. Same thing if you're cutting aluminum with a rotary stone or drum sander, run the stone or drum sander into piece of bar soap every few cuts and it'll stay pretty clean of imbedded aluminum. This of course leaves your bits and stones smelling clean and refreshing.
|01-30-2013 09:06 AM|
Hey F-Bird check out these bits. will these work ok. They are similar to what you have below.
I guess these are made for cast iron??? I have no idea.
|01-29-2013 09:33 PM|
|vinniekq2||1gary,do you have any experience with super stock engines? How do you measure cfm flow on stock castings|
|01-29-2013 09:19 PM|
We all know as casted OEM heads are all the same.Right??. I'm call it BS. So to follow the same pattern reaps the same results without a flow bench to check if your just hacking away at a pc of metal or really doing better or worst. Taking tech back to what amounts to caveman times is illogical.
The first set of heads done right usually the response is OH!!!. That's what I have been missing..........
|01-29-2013 02:45 AM|
Now that just doesn't make any sense.
|01-28-2013 09:28 PM|
|ChevroletSS||Thanks for the info. Greatly appreciate it. Can you point me in the right direction on some bits to use for porting. All I have is the port and polish kit from jegs which is ok but not efficient. I need something about six inches long id say and one maybe three inches long. A good carbide bit I guess. What do you suggest|
|01-26-2013 12:15 PM|
14101083 Cylinder Head
|01-25-2013 10:37 PM|
|ChevroletSS||Thanks guys. What is the common wall side|
|01-23-2013 08:36 PM|
Best way is to shave a little off at a time so you can get them dead flat without cutting any metal around the area since you want it as flat as possible.
|01-23-2013 07:13 PM|
|ChevroletSS||Ok guys when porting these heads can I smooth these round humps down so its nice and smooth or do I need to keep these there???|
|01-07-2013 11:04 AM|
When you get away from the port pocket things are much more subtle, therefore, it is easy to degrade the overall flow. What seems logical to the eye is most likely not where the flow will or wants to go. Most people reporting here state that there is little to be gained by working the port between the manifold face and the turn into the pocket. This really isn't factual, but this is an area where it is easy to do more harm than good. To tease this out you really need a flow bench and a decent understanding of how gasses respond in a physics sense. There are plenty of web sites that lead you into building an inexpensive flow bench using little more than a decent shop vac as a power source.
As far as getting all ports to match the old fashion way was to arrive a good test port then make templates of the port at critical points. The uncut port is ground at the same points to fit the templates then the material between the template stations is ground to smooth connection between these points. There are people on the web that sell templates for known port shapes.
|01-06-2013 10:44 PM|
|1Gary||Yeah,that's the link I posted earlier in this thread.|
|01-06-2013 09:38 PM|
The 12 v heating element is not regulated so 11 volts and 13 volts will give different temps so the readings that are taken will be different as well. Fine for the car since it adjust every few seconds and the alt provides the voltage once the engine is running.
its really important that you get the same results every day. Regular flow bench corrects for altitude and pressure. Along with temp and maybe a few other factors.
You can build a pro style flow bench. Here is a link for the best home kit i have seen. But may need more options for larger ports. Most vacums wont pull more than 200 cfm. With this kit and a vacum even the powerful one they recommend is 145 cfm at 28" and 210 cfm at 10". So totally useles for car heads that flow well.
Flow Bench | Digital Flow Bench | Flow Bench Kit
|01-06-2013 06:44 PM|
with the maf style flow bench ur readings can very well channge from day to day so its important if u dont finish in one day to go back and re measure a port u have done so ur ports u still have to do come out to the same number.
the 12 volt supply isnt as importnant as the 5 volt , the 5 volt is what gives the readings , normally the cars ecm supplys the 5 volts to the maf this way if it reads a lil high or low on the 5 volt line the ecm can compensate
in the case of a flow bbench if u have 5,2 volts one day and then 5.4 volts the next day ur results will read artifically high . so each day of testing or when changing from port to port its just as important to stick the dvom on the 5 volt line to make sure voltage is the same from port to port.
if not u can just see what the difference is and add/sub it from the reading u get when taking the flow measurements.
u can always buy 2 cheap vlt metters as well and ties one into the 5 volt feed line permantly and then the second onto the 0-5v output of the maf so u have constant readinsg of both lines
the 12 volt feed is used for the heating of the maf, the 5volt side is were the actual readings take place
|01-06-2013 06:25 PM|
Using Some plex in a 4 or 5 inch circle. With the head on top and the shop vac under neath. Then you can use strings and smoke to tell how things are flowing. Strings are really important for flow bench testing. And you dont need an expensive meeter and test unit that will not be acurate from day to day.
If you use the maf be sure to use a regulated power supply that can produce the same 12 v everytime. If it delievers more volts when it gets more volts it will screw the readings. Everytime you wife turns on the dryer you port work will be better. One of the main reasons home made flow benchs dont really work cause ypu need lots of tech equipment to support the meeter and reading of the meeter.
String always works if a little low tech. Also works great with smoke.
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