OMC 3.0L Epoxy Near Rod Slots

[cody161]

I have been working on cleaning up the rod slots in a block I’m building. I can feel with my finger a slight dip/depression right before the entrance to the rod slot. I had the idea to fill this are with epoxy and blend it to make a smoother transition. I have talked with a friend that doesn’t recommend doing this. I was wondering if anyone on here has ever done this and if there are any rod clearance issues, or other odd issues this may cause. I’m attaching a picture with the area circled in red that I’m talking about.

[rude tim]

I believe that dimple is to clear the rod bolts.

[powerabout]

save the epoxy for your late style diamond intakes

[rude tim]

I have a V8 that I am building now I went out and turned the crank one recolution and watched the rod/bolt clearance in that spot. It is for rod bolt clearance clearance.

[FMP]

So enough clearance to fill and profile ?

[cody161]

Thanks for the help guys.

[MattGreen]

I have a V8 that I am building now I went out and turned the crank one recolution and watched the rod/bolt clearance in that spot. It is for rod bolt clearance clearance.

Tim, are you building another 4.4L ?
if so tell us more.....

Matt

[Instigator]

I don't think there is clearance there to do much if anything.

I didn't understand where you asking about in your message.

[rude tim]

Its a 4 liter this time. Went back to a more conventional porting. What I tried on the 4.4 did not work out like I wanted. This motor should be better throughout the power band.

[rude tim]

So enough clearance to fill and profile ?

You would not get enougn epoxy in there to make a difference.

[FMP]

Be surprised what a little dip or bump can do to create an eddy

[Chaz]

Be surprised what a little dip or bump can do to create an eddy

OK , I give up . Please tell me what a dip or bump does to the surface tension of the boundary layer in an open air crankcase where not only that region is swooped once every 360* by an odd shaped object . But the entire circumference is subject to it's forces .
So how were you able to separate and measure which were caused by the bump , and which was caused by the crank and rod flingin round ~n~ round ... ?

No rush ... take all the time you need .... :p

[FMP]

You're so right, it's there for a reason.

[Chaz]

Now I would agree , if it were a closed environment like a port . And there wasn't a big club swinging around then yes , humps , bumps , holes , divots and changes in cross sectional area will tend to stall or pick up air speed which is easily measured .
There are even some old country boy method's of seeing where it's doin what .. ;)


https://www.youtube.com/watch?v=JTwUZxofrKg

[rude tim]

I use the poor boy flow bench, water hose. You can see a lot by running water over a surface.

[Chaz]

Grasshopper : you lift the rock out of the stream turn it side ways , put it back down , look what you did to the flow of water around it .... :D
If it were all that simple ... :thumbsup:

[powerabout]

wet flow flow bench, yes!!
florescent die in the air and high speed xray or camera, yes!

[Chaz]

Well the old #110 I use doesn't like liquids , can not filter out dies from the vacuum or manometer components . Nor does it have x-ray or thermal density imaging displays .
However it will blow enough finitely measured wind to quantify any changes I can make in my humble little shop .... :thumbsup:

I won't ask you to post picture's of your elaborate set up .... :p

[powerabout]

Well the old #110 I use doesn't like liquids , can not filter out dies from the vacuum or manometer components . Nor does it have x-ray or thermal density imaging displays .
However it will blow enough finitely measured wind to quantify any changes I can make in my humble little shop .... :thumbsup:

I won't ask you to post picture's of your elaborate set up .... :p
I asked a guy I know that sells the tiny high speed camera's to engine manufacturers he said price starts at $50k as does the xray stuff.
( dont need wet flow stuff with an etec, lol)

[Chaz]

I asked a guy I know that sells the tiny high speed camera's to engine manufacturers he said price starts at $50k as does the xray stuff.
( dont need wet flow stuff with an etec, lol)

Power ol boy ... that was so clever .. :nonod:

Lets see what you came up with :

Hi speed camera $ 50,000.00
X- Ray.............. $ 50,000.00
E-Tec ................$ 15,000.00
Trying to see
clear dry air ____ PRICELESS

[powerabout]

Power ol boy ... that was so clever .. :nonod:

Lets see what you came up with :

Hi speed camera $ 50,000.00
X- Ray.............. $ 50,000.00
E-Tec ................$ 15,000.00
Trying to see
clear dry air ____ PRICELESS
its what the manufacturers are all doing, trying to find out what happens in the combustion chamber.
Imagine what the F1 ( car) guys are doing

[Chaz]

And here I thought it would be Royal FMMTPulseple who wouldn't be able to remember that we were talking about rod slots ... not combustion chambers ..:p

[powerabout]

And here I thought it would be Royal FMMTPulseple who wouldn't be able to remember that we were talking about rod slots ... not combustion chambers ..:p
this conversation is all up in the air ( with some fuel in it if your a non etec'r)
Actually the issue is nobody that I could find has a cfd program that deals with pulsed air hence we have plenty of theory but no facts other than resultant HP increases/decreases

[Chaz]

Well in reality , charts , maps , cfd programs , crayons , pocket protectors and coke bottle glasses will all produce a wide spectrum of theories .

The sad truth is , if you want facts . As my mom would say :

"If you want an omelet , you better start breakin eggs"