Gurney head 302 on ebay
- Thread starter RD40866
- Start date
A Bit of history on Gurney Weslake Heads
The Ford V-8 Engine Workshop
Gurney-Weslake Small Block
1967 Gurney-Weslake 305 "Actually, we began our inquest with extensive rework of the existing 271 hp heads.", said Dan Gurney holding back a smile.
"At the peak of our testing with the 271 hp cast iron heads on a 325-inch block, we were pulling as much as 448 hp on gasoline. It was about this time we figured a few improvements along the lines of a new head design might give us even more power, so we got after it."
The new heads, cast of aluminum alloy by Alcoa, did evolve. The intake ports were a short shot, leading directly from the carburetors and aimed straight at the combustion chamber. No intake manifold is used. The Webers bolt directly to the cylinder heads. Steel valve seats were used on the 2-1/32" intakes, and bronze on the 1-5/8" exhaust. Normal 45 degree seat angles were used. Rockers are shaft mounted with removable stands. Three different heads designs were developed, including one to fit under the stock hood of a Mustang.
Not much remains of the stock 289 HP bottom end. The crankshafts were custom made by Dearborn Crankshaft Company. Bearing inserts were taken from the Ford DOHC Indy engine. Carrillo rods, super finished and shot peened were fitted. Stock 289 oil pans were chopped up and baffled for each particular type of track. Probably the most interesting modification was the addition of a main cap girdle. Even so, main bearing saddle cracks were common. Stock 289 head gaskets were found to work reliably.
Camshaft development was handed off to Jack Engle, ultimately settling on a relatively short-lift long-duration camshaft. Rev kit springs were placed between the lifter valley and the underside of the cylinder heads to extend the RPM range of the valve train.
Both 289 and 305 CID versions were dyno tested. On gasoline, the 289s developed as much as 506 hp @ 7800 rpm. The 305s pushed 520 hp.
ENGINES FLATHEAD FE SMALL BLOCK BIG BLOCK CLEVELAND
The Ford V-8 Engine Workshop
Gurney-Weslake Small Block
1967 Gurney-Weslake 305 "Actually, we began our inquest with extensive rework of the existing 271 hp heads.", said Dan Gurney holding back a smile.
"At the peak of our testing with the 271 hp cast iron heads on a 325-inch block, we were pulling as much as 448 hp on gasoline. It was about this time we figured a few improvements along the lines of a new head design might give us even more power, so we got after it."
The new heads, cast of aluminum alloy by Alcoa, did evolve. The intake ports were a short shot, leading directly from the carburetors and aimed straight at the combustion chamber. No intake manifold is used. The Webers bolt directly to the cylinder heads. Steel valve seats were used on the 2-1/32" intakes, and bronze on the 1-5/8" exhaust. Normal 45 degree seat angles were used. Rockers are shaft mounted with removable stands. Three different heads designs were developed, including one to fit under the stock hood of a Mustang.
Not much remains of the stock 289 HP bottom end. The crankshafts were custom made by Dearborn Crankshaft Company. Bearing inserts were taken from the Ford DOHC Indy engine. Carrillo rods, super finished and shot peened were fitted. Stock 289 oil pans were chopped up and baffled for each particular type of track. Probably the most interesting modification was the addition of a main cap girdle. Even so, main bearing saddle cracks were common. Stock 289 head gaskets were found to work reliably.
Camshaft development was handed off to Jack Engle, ultimately settling on a relatively short-lift long-duration camshaft. Rev kit springs were placed between the lifter valley and the underside of the cylinder heads to extend the RPM range of the valve train.
Both 289 and 305 CID versions were dyno tested. On gasoline, the 289s developed as much as 506 hp @ 7800 rpm. The 305s pushed 520 hp.
ENGINES FLATHEAD FE SMALL BLOCK BIG BLOCK CLEVELAND
Marco, I was on the telephone with my engine guy today, still waiting for him to send me some pictures. I have not forgotten. BTW, he is now saying that he would rather build a shorter stroke, smaller displacement engine than the 427 cid we had anticipated. He wants it to spin spin it to 8000, as he feels it will be a better balanced engine. Displacement will be somewhere between 385 and 405 cid. He says the GW valvetrain is good to 8500 with no problems.
Jim Rosenthal
Supporter
Here's an interesting and I think funny story I heard yesterday about GW heads:
Friend of mine has a GT40 (1136) which has a Mathwall engine, probably puts out about 420 hp and because of the long final drive ratio in the ZF this car has a top speed around 200. The engine has Dart heads, which were prepared with the engine. Friend also has a set of GW heads, new never run, and asks a buddy who is a Ford hi-perf engine builder about using the GW heads, very authentic for a GT40, what kind of performance change could he expect, etc etc. Buddy gets all the info, says to my friend,
"the GW heads probably won't cost you more than 15-20 hp...".
Heads are still on the shelf, car runs great with Dart heads, my how technology has moved on since the sixties...
A set of GW heads if you can find them are 5K-8K. A set of AFR heads is 1.5K. Not a difficult choice if you're like most of us and on a budget...the ride in the car was GREAT and the noise is indescribable...
Friend of mine has a GT40 (1136) which has a Mathwall engine, probably puts out about 420 hp and because of the long final drive ratio in the ZF this car has a top speed around 200. The engine has Dart heads, which were prepared with the engine. Friend also has a set of GW heads, new never run, and asks a buddy who is a Ford hi-perf engine builder about using the GW heads, very authentic for a GT40, what kind of performance change could he expect, etc etc. Buddy gets all the info, says to my friend,
"the GW heads probably won't cost you more than 15-20 hp...".
Heads are still on the shelf, car runs great with Dart heads, my how technology has moved on since the sixties...
A set of GW heads if you can find them are 5K-8K. A set of AFR heads is 1.5K. Not a difficult choice if you're like most of us and on a budget...the ride in the car was GREAT and the noise is indescribable...
G
Guest
Guest
In 1989 a friend of mine, who has since passed away, built a 302 with G/W heads. The engine went into #1076. With a flat tappet cam, and webbers, it pulled 540 hp @7000 RPM. Admittedly it was a racing engine, and it had about 12.5 to 1 C.R., but that was still very good for that time. The point is that if you are lucky enough to have a set of these heads, you should be able to produce more than enough power. Besides, they make a very pretty package.
If the heads pose any problems, it is that the intake ports are quite large. I would like to see how they would do with EFI. If anyone has done it, I would like to hear about it.
If the heads pose any problems, it is that the intake ports are quite large. I would like to see how they would do with EFI. If anyone has done it, I would like to hear about it.
Similar threads
