Hi,

yesterday I started porting my housings and i jumped with the grinder out of the port
Look at the picture:

(inside the red marking you can see my work)
You can feel the marks a little bit with the fingernail.

Is that housing now very good for looking at it on rainy days? Or can i use it if i (maybe) polish the spots?


Another question:
Here is the primary port - i started with the porting:


I'm using the pineapple "large street port" templates. Maybe you can see the marking on the picture at the top left of the port. I should go further, but i am unsure how far and "deep" i can go (i don't want a hole to the coolant).

Thanks for advice,
Daniel

 

is that porous spots around the port?
if so they are worse than what you did,
I would say make sure you smooth down what you did and you should be fine.
my 2 cents
matt

 

Hi matt,

the black spots around the port is paint for the porting template markings.

Thanks for advice!

Daniel

 

yeah, intake stroke outside of the oil seal

 

I just did the same thing porting out one of the end plates. Probly a little worse than yours. I sent it to be lapped so I'll see what the lapping did for my screw up.I'll let you know.

 

I think most of us that rebuild motors port the housings first before we take housing in to get lapped. That helps with that problem. Remember it is not the low spot that the grinder dug out. You won't even lose 1 hp. It is the high spot that will catch a seal and nick it up. For a friend who nicked his housing, that did not need lapping, I cleaned it up with a palm sander and progressively finer grit. Just don't scratch it all up. It takes some time. If you have an old junk housing or piece of metal practice on that first.

Regarding the closing edge I don't own one of pineapples templates so I don't know how far they took it. But personally I like to make it a very gradual taper. That way the incoming air doesn't have to make that sharp bend. Plus it you are just adding a radius to that closing lip you don't have to worry to much about the water jacket.

On some of my housing, can't remember if they were the 12A or 13B, I can stick my little finger in the water jacket and reach the backside of the intake port. Then I know how much material is left and how close that template maker makes it. I think on the S4 I could stick a wire down the EGR passage and get a little idea how thick the casting was in that one spot. Again that is only from memory.

FYI I now run some pretty long grinding bits that I never walk all the way out. I also hold the grinder with two hands and rest them on my work. Even so I often tape off the unported area or lay a piece of scrap sheet metal over it so I can't knick one (any more).

My two cents.

 

i used to do that all the time when i first started. none of my ported engines have shown bad compression or smoking. i think you'be fine. i've learned to use duct tape for surface protection, so for future reference, try that. good luck with your build.

 

The front housing on my current engine had a bunch of dents/dimples in it, near the top about an inch below the coolant seal area. Smack dab in the middle of the side seal track, in other words. (It looked like it was transported with something else next to it and dinged it several times) Every ding had a raised area around it.

I first gently used a *swank* miniature, curved file to clean off most of the high spots, then the leading edge of a small regular file to shave off most of the rest. Then I kept running my finger over it and used a sharp gasket scraper to shave them down to the level around the housings.

About 9k on the engine, so far still has great compression.

 

The dents are tiny and the seals move past quickly.

 

Hi,

that is nice to know, thank you guys! :-)

Daniel