Thoughts Guys

[Scufty]

I have a 427 S/O
I took at look at my heads today ..on the outside the casting numbers are C5AE-F and right beside that is another number 5L15
curious as to what the other numbers are for...I have No numbers on the inside of the heads when I took the valve cover off.
From what I understand these are Med Riser heads from a 65?
I also understand that High riser heads are the best ..where do low riser heads come in? ALso I have a performer 390 intake which I think isnt the best? Whats do you guys think? Holley 750 DP
Solid Cam (mild) Solid lifters, Roller rockers.
There has been a little port work done to the heads.
I also have a Holley STreet Dominator intake sitting here on the bench. Is it any good?
Wondering mostly about the heads and the intake combo as well what I have to be concerned about when purchasing a intake? I was told that you need a high riser intake with high riser heads. Do I need a med riser intake? any input would be great thanks guys

[Scufty]

Come on guys I know you have more info than that

[FFR428]

The 5L15 is just the date code of 65/Nov/15th. Nothing wrong with medium riser heads that's for sure!!! High risers were 63-64. Low risers were the first early head port design. Many different castings also. Can't comment on the Holley intake but I'd stick with the MR heads if they are in nice shape.

[Excaliber]

The intake has to match the heads, low, medium, high, tunnel port or whatever. Matching intake required, you might get some mis-matched intakes that fit, but they won't be 'right'.

[FFR428]

Originally Posted by Excaliber

The intake has to match the heads, low, medium, high, tunnel port or whatever. Matching intake required, you might get some mis-matched intakes that fit, but they won't be 'right'.

Hmmm.. what about the 428 CJ? LR head port size used with a MR intake port size. Seemed to work ok for TASCA and later Ford when they copied the TASCA design as the 428CJ we know today.

But I get your point E... just ribbin ya a bit. LOL


G.

[Excaliber]

Hmmm... what were they thinking, those TASCA guys? Why would you want to run low rise intake on medium rise heads, certainly not for 'performance'. Perhaps it was a hood clearance issue?

[flwolfman]

Low, medium, and high rise has to do with how tall the intake manifold is and the intake should be matched to the heads. (low to low, med to med, and high to high). This will give you the best performance. Hood clearance can be a problem with medium and high rise heads/intake. Lower usually more torque, higher usually more hp at rpm. The medium rise heads you have are great for the street. Other options you are asking about largely depend on what you plan on doing with the car. What type of driving and so on. Hope this helps some, Jim

[FFR428]

Originally Posted by Excaliber

Hmmm... what were they thinking, those TASCA guys? Why would you want to run low rise intake on medium rise heads, certainly not for 'performance'. Perhaps it was a hood clearance issue?

Other way around.

[Excaliber]

OH!!

Well that DOES make some sense. It's pretty easy swapping out the intake and cheap compared to the heads. Medium riser on a low riser heads, sure why not! Do the best you can with what you have to work with.