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Thinking about porting my heads

Leadhead

Leadhead

Well-Known Member
Anyone who's done it before have any advice? They're 1969 048 (not 049) heads off a 396. They have the 2.06/1.72 valves. I've been watching some videos from Mark Jones and David Vizard, and it looks like something I could tackle. Any tips from any of you DIYers? Is it worth the effort?
 
I ported a set of Edelbrock Performer Rpm small black heads. Used sand paper rolls and cones using a pneumatic die grinder. Mainly port matching. I’m sure aluminum is way easier than iron and I’m sure you’d need a carbide bit for that. I actually had them checked on a flow bench and they moved more cfm than the advertised numbers.
That’s probably of no use to you but it seems like it’d be a fun project.
 
Leadhead said:
Anyone who's done it before have any advice? They're 1969 048 (not 049) heads off a 396. They have the 2.06/1.72 valves. I've been watching some videos from Mark Jones and David Vizard, and it looks like something I could tackle. Any tips from any of you DIYers? Is it worth the effort?
Click to expand...
Biggest gains are bowl blending under the valve seat and smoothing the guides. Mark's videos talks about what to do on each side of the guide.
I wouldn't bother with port matching.
There is a sharp ridge under the valve seat; just smooth that a give a gradual radius into the port.
I've done two whole sets of heads so I'm an expert ! (when I'm 50 miles from home and carrying a briefcase)
68Chevelle probably has some pointers
 
One place to get carbide burrs is mcmaster.com
I use the "double-cut egg shape" extended length
This is what I would order
Extra-Long Bur with 1/4" Shank Diameter, 1/4" Diameter x 3/8" Long Oval/Egg Head, Number SE-1L6, Double Cut #4324A32 $19.62

www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com
 
I will tell you this, if these are closed chambered or semi-closed chambered heads sell them and put some 781's on the engine. Put a stock set on my old 396 back in the day and the car ran better, was quicker and faster and I could run pump gas over any of the old BBC closed heads, there was a reason GM went to open chambers, better emissions and the open stuff makes more power. Open chamber heads just make more power even without and porting over CC heads. I will see if I can find some pics of my CC 215's I ported a few years back and even with a ton of work my 360 PP heads made more power on the very same engine.
 
Leadhead said:
Yes they are closed chamber. So don't waste time?
Click to expand...
You can port them but without chamber mods they will not make as much power as a set of stock open chamber heads with just a valve job. If you do port them I would for sure use the stock valve sizes as putting in 2.19 and 1.88 valves have way too much shrouding hurting power IMO. Here is the times I ran with a set of peanut ports the 1st. time I used those 236 heads with had 2.06 and 1.72 valve sizes and mild port work. The car ran ran the best of 11.72@112mph close to 113. I took the engine apart and put the 215's on which had the bigger valves, oval ports and the same amount of porting. The car ran the best of 11.66@113mph so all the work of putting the bigger valves in and having a bigger intake port did not seem at least on this BBC make that much difference all else was pretty much the same. I had run closed chamber heads for year thinking that the boost in compression was the hot ticket until the test I ran in 2019 with both set back to back and the funny thing is last year I ran the 360's that are peanut port heads and put the car in the 11 teens with 8:1 compression open chambered heads.
 
The 1969 396/427 "063" ( I think 215 and another head are same) heads are 100.9 cc Semi open/closed chambers that IIRC Edelbrock copied their 100 cc BBC head to help raise comp. on low comp. 454's, I had a set I used sanding cones to smooth everything but I left chambers alone as PO done something but I did have 1.88/2.19 SS valves & new guides and a good VJ done and the engine really was fun after that, I did buy an Isky piston notch tool to cut the radius on the dish piston valve relief wider for the 2.19 int valve & deeper for the .533 lift cam but ended up $1,100 in iron heads :( Not including the Isky tool
 
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