Wich templates for porting 452 heads>

[squeakfinder]

I just got the templates to port big block heads from Summit. They are Mopar performance. Well, I don't quit understand what I'm looking at.

It tells me it is for 2.08 intake and 1.74 exhaust valves. That would be correct for 452 casting heads. But, the instructions say it is for 3614476 casting, which are stage IV heads. 

This seems kind of vague, Summit only list them for big block heads. Do these templates work with 452 head casting?

[firefighter3931]

Yep, those are fine for the 452's. Originally, the porting templates were designed for the stage 4 iron heads which are basicly open chamber 906/346/452 castings with a little more meat for porting. The templates work very well if you're keeping the stock 2.08/1.74 valves. Take your time and enjoy the grinding....it will make a noticable difference. 



Ron

[Purple440]

Hey Ron,

First off, I've enjoyed your posts as I searched the archives...same with Neil.

Do templates prevent a newb like me from ruining a set of heads?  I also have 452's and am interested in porting.

Thanks,

- Doug

[squeakfinder]

Thanks Ron.

Purple440-

The instructions say to do a valve job AFTER the port work. I'm assuming if there are any mistakes made, for instance if the valve seats get hit they can be cleaned up afterward.

But if bronze  guide bushing's are used, fit them BEFORE porting.

[firefighter3931]

Thanks Ron.

Purple440-

The instructions say to do a valve job AFTER the port work. I'm assuming if there are any mistakes made, for instance if the valve seats get hit they can be cleaned up afterward.

But if bronze  guide bushing's are used, fit them BEFORE porting.

>That is correct....portwork first, VJ last. 

Doug, to answer your question on newbie portwork ; the templates are indeed made to prevent a boo boo.....you don't want to hit water by going overzealous with the carbide. For the majority of street cars running .500 lift cams, the templates are all you need. The bigger flow numbers result from profiling the guidebosses and reworking the roof and short turn....but those numbers are mainly improved in the high lift areas....not below .500 valve lift. The 452's are the most responsive to the bowl work in terms of increase with the templates.


Ron

[Chryco Psycho]

the templates work  great for shaping the port behind the seat , I only went 95% with the templates as it seem to want to remove the seat entirely , it doesn`t show you have to shape around the valve guides thoiugh which is where a LOT of power hides , the attached pix will give you an idea how to port that area 

[Challenger340]

Just some suggestions for anybody who's gonna port their own heads.
It's "usually" a good idea to get the guides done first, and a "roughed" Valve seat done.

This is because all porting is usually done to the "seat", or rather, to compliment THAT valve seat, and "where" it is.

Nothing worse than going ahead and porting first, then getting the Valve Guides and seats done, only then to find out the seat is moved over slightly from where you ported.
I'm just saying "best" results occur this way.

Not alweays practical for alot of guys I know, but if you're gonna port your own, ask your shop if something can be arranged.
I do this alot for my guys.

I don't like porting anymore, so I usually will put the guides in for guys, rough out a seat, I even do 1 Intake & exhaust port for them as a guide, then send them home to continue.
When they're finished, they come back, and we correct any "dings", & finish the head rebuild.

just some thoughts.

[Rayzor]

I brought my heads home just after the hard seats and guides were put in. the seats had not been cut yet so I had a no major problem with bumping the seat and having to recut it. If you do go to larger vales its worth it to have them run a bowl hog threw them as it will save you major grinding.

[is_it_EVER_done?]

If you have a three angle valve job done with the "bowl" angle at 70 to 75 degrees (standard and typical angles), you will save a couple hours of grinding as the bowl cut will remove the vast majority of the material that you would otherwise be removing first.