I've had these pics around for a couple of years now since I ported these heads (sorry...I didn't take a pic of the intake ports). Maybe this will help anyone considering a port job on '69 or '70 351w heads.
The intakes were scribed to match Felpro 1262 gaskets ( 2.10 x 1.28 ). The exhausts were scribed to match Mr Gasket Copperseal gaskets ( 1.48 x 1.25 ). It's important to note that the gaskets were moved up as high as they would go ( with a couple of bolts at each end screwed into the head for alignment ) to put more emphasis on the port roof without lowering the floor. IOW, the port roofs are being raised while the floor is being left essentially intact as is. This tends to straighten the ports increasing flow. Once they were scribed, they were opened up to match the scribe marks and smoothed into the port. The roof was raised by something like 1/8" and the sides were widened significantly. The thermactor hump is history. The valve guide area was reduced significantly and smoothed. The throat was opened up somewhat to accomodate the larger 1.94/1.60 valves. The short side radius was smoothed to remove casting flaws, but not much more was done to the short side radius except to widen it. The hump due to the pushrod hole in the intake was reduced by about 1/16" to 3/32" to smooth this transition. Lowering it much more than that would have resulted in the area being thinner than I was comfortable with.
Final intake port volume is 160cc. Exhaust port volume is unknown, but the ports are at least 40% larger than stock...you can drop a pencil right thru the ports easily. I would not recommend going any larger than 1.48 x 1.25 on the exhaust ports...this is on the large end of the spectrum and it becomes a bit more difficult to find headers that have inlet ports as large as the head port opening. I am using Dougs tri-y headers.
The heads were given to the machine shop to add screw in studs, guide plates, SS valves, bronze guides, hardened exhaust seats, re-surfacing, and a valve job. $550 later they were ready for installation. Final chamber volume is 61cc.
The heads are on my 331 which has chassis dyno'd at 335 RWHP @ 6300. Rear wheel torque is 337 @ 3800. Flywheel HP and Torque are probably in the 395 to 400 area. All in all, my goal was a streetable yet good performing small block and i'm very pleased with the performance of the engine.
11/02/06 Update:
I didn't take enough pics of my heads when I built my engine over 3 years ago, but since it be apart I shot some pics that I have wanted to share for a while for anyone consdering DOOEs in their engine buildup.
I chose DOOEs for my 331 because I get more satisfaction from making HP and I enjoy experimenting. This is my second or third set of heads that I have ported. I can remember porting a set of '66 390 GT heads back in the 70s with a dremel tool and my motorcycle helmet for protection...geez that took a while to do, but the engine ran very well.
The engine specs are in my sigpic and the HP and TQ were both in the 400/400 area with peak HP and TQ at 6400 and 4100, respectively. With the few mods i'm planning this time around, i'm anticipating 420-425 HP and 405 TQ.
The intake volume is 160cc and the exhaust volume is 60cc. Felpro 1262 gaskets (2.10 x 1.25) and a Copperseal gasket (1.48 x 1.25) were used to provide the outline for the ports.
The gaskets were placed on the heads with the existing port toward the bottom of the gasket opening and then the heads were scribed. I did this to put most of the emphasis on raising the ports. The intake roof was raised about 1/16 to 1/8 and the exhausts were raised about 1/8. I did very little to the short side radius except to smooth it. Both intake and exhaust runners were widened significantly. The throats were opened up too to accomodate the 1.94 and 1.60 valves
The intake hump for the pushrod hole was taken down to within 1/16 to 1/32 of the hole. The thermactor humps are totally gone in the exhaust ports and the raised valve guide area is also completely gone. The intake manifold was port matched to the heads.
I slightly reshaped the chambers on each end to reduce valve shrouding. Final chamber volume is 61cc. Finally, I used sandpaper rolls to give the ports a semi smooth surface. Polishing intake ports can be detrimental and in general polishing only has a small contribution to flow so I didn't bother.
I found some irregularities in the intake runners around the pushrod hole hump last weekend that I didn't catch 3 years ago so maybe they will flow better now.
The scratches in the exhaust ports are from a sandpaper roll when I was trying to remove some of the carbon.
intake inlet
intake bowl
exhaust outlet
exhaust bowl
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Tracy Blackford: Corona, Ca
'65 FB Mustang 331 with H-beam 289 rods, KB 322's, 282S cam, fully preped 351W heads. T5z and 9" 3.50 trac loc. 335 RWHP @ 6300 RPM
<font size=-1>[ This Message was edited by: blkfrd on 11/3/06 1:22am ]</font>
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