Just what it says.
Do not do any metal removal (grinding) to the floor of the port. Other than smoothing or blending the corners to new side wall locations, leave the port floor at it's as cast location.

Why ?
Because this mandates changing the "short turn radius" to blend in the new floor location. Any altering of the short turn radius from the as cast dimension, will affect how the air / fuel flows around the sharp corner as it heads toward the valve / seat opening.
Sharp turn, bad, large turn, good.
Take a look at modern day sport bike cylinder heads. The designers have made the intake ports almost "straight" from the valve seat to the manifold / throttle body. This design, with almost NO...short turn radius is a VERY good design for high flowing intake ports.

Hope this helps.

Mike

 

Asking if a porting is good based on pictures is like asking how hot the sun is in the shade..

A porting might look "good" but flow like crap. The only way to know if it has helped - is to measure the flow, both speed, absolute flow and swirl. Guessing by looking at pictures really does not help at all.

(Remember everyone can make ports flow more - but not all can make them flow better

 

Well if you don't think they're an improvement,why don't you come check out how my car's drive in the videos and you tell me how they pull is compared to minis with such few mods. just ask around I've sold at least a dozen full ported sets ,me and all my personal friends are running among their cars too as well as a bunch of customers that have them
And they absolutely do help performance especially now that I'm starting to sand blast the inside smooth them down even better .
So it's always easy to hate on someone else's work when you sit there and do nothing other than judge but personal opinions can be kept to themselves because unfortunately people like you tend to push around personal opinions as facts...

 

While what you say...on the surface is basically correct, after 45+ years of doing port work on many different brands and types of cylinder heads and intake manifolds, spending MANY dollars/time on flow bench time...yeah, I can do a decent job of "seeing" port work and having a good idea how well it will...or...won't work .
And yes, you are mostly correct about more and better. You MUST know what the heads will be used for before taking a grinder (or CNC machine) to a set of heads. But you must also understand, thay many times, all the measurements...GO TOGETHER !
Now, do you have any more "buzz words" to toss out ?

Yeah, these heads are for a supercharged alcohol burning 392 Chrysler Hemi.
And yes, they flow very well thank you.



Mike

 

Whoa! easy there fella.. I think you read my post like the devil reads the bible..

All i'm saying is that you will probably not get any constructive feedback based on pictures alone.

I do not in any way see that I "push personal opinions as facts" in any way.
And I do not "do nothing". I have been porting heads for maybe 15 years, I know that what looks good might not be the best. I also know that porting takes AGES. One thing is absolute flow - almost all can get more flow, but it will happen at a reduced velocity - or even poorer flow at low cam lift. If it works for you - good on you I do not doubt that.
I'm merely saying that it is impossible to judge if it is "good" from pictures alone. Show us some flow graphs @ different cam lifts, then it is easier to give you feedback. (And when you receive feedback, be prepared that there might be feedback that point in a direction you do not anticipate).

 

My friends , customers and i have no complaints and nothing but improvements from the porting jobs...i wish there was a dyno that didnt charge outrageous amount by me so i could do some better tests...
I get there's definitely room for my porting jobs to be better but they're forsure improving over the stock stuff.
do I think it would add power on a stock engine ? No, doubtful , maybe lower iats but when combined with a reduction pulley , cam , bvh and larger throttlebody and intake. It definitely compliments them very well..

 

i did the horns, sc inlet/outlet and intake pipe as well a few months ago. Much easier w/the sc apart (was replacing seals and grease repacking). Kind of wished I had maxed out the outlet on the SC but feared drivability impact. I think maybe a good 10-15% of area could be gained there.

 

That would be an interesting "experiment".

Years back, when the "first" superchargers were pulled off of diesel engines, a VERY large opening in the blower case was open to the manifold. As engines started making more power, and the lead mechanics were noticing larger and larger differences in cylinder temperature and the way that the spark plugs were burning.
Eventually, someone came up with a spacer plate that only allowed the case opening to about 1/4 the original square inches AND it was in the shape of a...triangle. Other openings were tried, even just smaller rectangular openings, but the triangle worked the best.
Eventually, as the original GM blower cases were used up, and the cases got longer in length, that "triangle" was cases into the new cases, from the original 6-71 all the way to the 10-71 cases, as the Nitro and Top Alcohol engines use today.

Now one note to all of this - ALL of the above work was done on cases that sit directly above the cylinder heads of the engine. NOT divorced, alongside of the engine block.

POSSIBLY...opening up the outlet, in this case...could possibly be very beneficial..!
All this is to say, don't go too large to start, and have an outlet for...more cases to experiment with !

A pretty modern day, Top Fuel, nitro engine (about 11,000 hp worth). Obviously cant see the bottom of the supercharger (under the blanket), but yeah, this blower case has a...triangular opening, about 1/4 to 1/3 the size of the bottom of the case.


Mike

 

from a small car fan, ^ that ^ is beautiful

I get what you are saying too. The standard port size can be close to accurate for flow rate. Only finishing required.

And true, the genuine way to know if work has improved the head is by testing at small & large valve openings.

Good on the OP for having a go. Like many of us, he would have learned - hopefully enjoyed, & probably do a better job of his next attempt because of it :-)

 

I don't remember if I removed the boss material shown here as it didn't align w/the lobes so I didn't see much value. The apex region is where I did consider opening up as the lobes do reach further into the casing (ported sc shown):

 

Hmm, IF WERE ME...
The area on the left side of this picture...I'd...figure out a way to FILL IN...this area. Make the "new" wall even with the rotor lobe ends.
Right now, the airflow is severely interrupted by the "open" area to the left of the ends of the lobes. This ISN'T...a very good design, airflow wise. Where is the air going, into a dead airspace that does nothing for getting that amount of air into...the airhorn. Useless dead airspace.

Unfortunately, what I mention above would be very expensive and or time consuming to any welding and subsequent remachining of the case to resquare everything..


Mike

 

Best in the bizz


https://jokerzperformance.com

 

I found another NEW sneedspeed intake Manifold and check out how much needed porting out to just gasket match the ports and open up the inlet.. I also used media blast to smoothen out the porting and any casting flaws and then I went over the inside with 1500grit sandpaper so it's atleast 2x as smooth as stock and has 0 casting flaws or any dead spots for airflow. This will absolutely stop the cyl1 lean issues ( though I'm sure my ported stocker is doing just fine but this will be better )..

 

I cant wait for TPE to release their manifold. Will make trying to enlarge the standard one redundant.

 

you and me both brother...
I HOPING they make it out a composite plastic material and not metal..on a NATURALLY aspirated v8 but on nitrous , the aluminum eldelbrock intake Manifold caused much higher iats and heat soak and the plastic options were always better..
and the plastic ones had no problem holding turbos and superchargers.
here's the most recent Manifold I did.