OU812...intake runner angle

OU812,
I have noticed in several of your post and one to me that the angle of the intake runner on the intake vs. the angle of the intake runner on the head is very critical as far as flow is concerned.

I have a set of ported A3 motorsport heads and a Edelbrock 351Y which is ported by the Nascar guys that I am going to try and mate together.

The Intake runner angle in relation to the flange or mounting surface where it makes contact with the head is as follows. The roof angle is 0 deg. on the inner 2 runners on each side of the intake and 3 deg. up angle on the outer 2 runners on each side of the intake. The floor of the intake is 7 deg. up angle on all ports.
The head roof angle is 7 deg. down and the floor is 4 deg. up angle.

Just to note the A331 intake that I have is unported and is supose to match the A3 head has a 4 deg. up angle and a 7 deg. floor angle.

I will be milling the flange of the Edelbrock 351Y about .250 on each side of the intake because when it is installed on a 9.2 block with the A3 heads there is about a .250 interference between the intake port and the head intake port, the intake being too high.

Can you give me your thoughts on these angles and if they will be OK> Seems that there is no match as far as angles are concerned, however it may be that I don't know what to look for or what the intake is trying to do in relation to the head port itself. Also, should I leave the intake a little high or set it lower based on the angles listed above to better the flow?

Then again, this may seperated the men from the boys!!

Thanks
[addsig]

The roof and floor angles should match, as much as possible.
You want at least 1/2" of the intake manifold runner and at least 1/2" of the head runner to be exactly the same angle. Sometimes you have to use epoxy to get this right. I would say no more than 1° between head and intake manifold roof and floor alignment. I have seen where correcting this alignment made very measurable HP.
Sometimes you even have to mill the flanges to get the intake to set down so you can raise the angle. Other times you need to add epoxy.
Just depends on the circumstances.
Hope this helps...

Brian
[addsig]

OU812
Do these angles mentioned above seem like normal intake and head angles?

Where can I purchase some good epoxy? Is is compatiable with methanol?

Thanks
[addsig]

I use the z-spar top coat epoxy. Can usually get it from a marine place or Mondellos.
I don't really pay attention to what the actual angles are of any given head/intake combo, but I make sure to make them match.
If you use methonal, you will want to coat the epoxy with a clear coat of enamel after it has cured.
You may have to do this every so often too. methonal is harsh and erosive!
Brian
[addsig]

OU812,
One more question.
If you had a intake where the height of the intake port is about .060 smaller than the head port, would you try and get your match at the roof or the floor of the head? I would guess roof.

At about .750 lift my heads pick up turbulance on the short side. Is there anything I can do to correct it with the intake port angle or mismatch?
Nothing's perfect here......

Thanks
[addsig]

Intake manifold FLOOR and intake port FLOOR is more critical than roof.
Because of the air speed on the floor.
Bolt the intake on the head and then flow it. See if the turbulence goes away. If it does, then your probably ok on live engine.

[addsig]