by Steve Holmes » Mon Aug 19, 2013 3:48 am
STG69 wrote:Steve,
When u say the fords kept blowing engines. Do u know specifically what was letting go? I know the rocker gear was a weak point even in 69/70.
It seems to depend on who is telling the story. Vintage Motorsport magazine ran a brilliant multi-part series on the Trans-A series, and said this of the tunnel-port motors in 1968:
".....The general layout of these new heads was derived from the heads Ford supplied for the 427ci big blocks raced in Nascar.
"Instead of curving around the pushrod holes, the intake ports went straight from the manifold to the cylinders. The pushrods were housed in tubes that literally went through the intake ports, ie, a tunnel through the port. This tunnel-port design created less restriction, plus allowed larger intake valves. Topped with a new dual-quad intake manifold, the tunnel-port produced a useful 440hp on the dynamometer.
"Unfortunately, when you raced the tunnel-port V8 on a curvey track and subjected it to high lateral loads, the new heads trapped oil and the engines seized".
However, Lew Spencer, Shelby team manager, when interviewed in the same article, tended to lay blame at the feet of Ford, rather than the design. Thats not to say he liked the design, or thought it could work in a road-racing environment, but he appears to lay blame for the poor reliability on the set-up that Ford and Shelby had going. He said:
"1968 was a bad year. We didn't have any engines. Well, we had the tunnel-port engine, which was a disaster. The tunnel-port engines were built by Ford in Dearborn and shipped to us in a crate. We were not allowed to open the crate without a Ford engineer present. If an engine blew - and the engines blew every time we ran them - it went back in the crate and back to Ford. In 1967, we built our own engines and had not one failure. In 1968, we used Ford's engines and had failures at every race. It was very frustrating".
He later went on to say:
".....even though our paychecks came from Shelby, we felt we were Ford employees. We had Ford engineers working right with us in the Shelby shop. Whenever there was a failure, the Ford guys would run to the phone and call their boss. If the engine failed, the engine engineer would call the engine vice-president and say, "The engine failed, but it was the transmission's fault".
"If the transmission failed, the transmission engineer would call the transmission vice-president and say, "The transmission failed, but it was the engines fault!" We all thought it was pretty funny. But of course, since nobody from Ford ever admitted there was a problem, no problem ever got fixed. So that was kind of sad".
So, reading what Spencer said, it sounds like Shelby were caught in typical large corporation politics, where the right hand doesn't know what the left is doing, and everyone is guarding their own back. Whether Shelby's own guys could have got the tunnel-port motors to run reliably will never be known.
[quote="STG69"]Steve,
When u say the fords kept blowing engines. Do u know specifically what was letting go? I know the rocker gear was a weak point even in 69/70.[/quote]
It seems to depend on who is telling the story. Vintage Motorsport magazine ran a brilliant multi-part series on the Trans-A series, and said this of the tunnel-port motors in 1968:
".....The general layout of these new heads was derived from the heads Ford supplied for the 427ci big blocks raced in Nascar.
"Instead of curving around the pushrod holes, the intake ports went straight from the manifold to the cylinders. The pushrods were housed in tubes that literally went through the intake ports, ie, a tunnel through the port. This tunnel-port design created less restriction, plus allowed larger intake valves. Topped with a new dual-quad intake manifold, the tunnel-port produced a useful 440hp on the dynamometer.
"Unfortunately, when you raced the tunnel-port V8 on a curvey track and subjected it to high lateral loads, the new heads trapped oil and the engines seized".
However, Lew Spencer, Shelby team manager, when interviewed in the same article, tended to lay blame at the feet of Ford, rather than the design. Thats not to say he liked the design, or thought it could work in a road-racing environment, but he appears to lay blame for the poor reliability on the set-up that Ford and Shelby had going. He said:
"1968 was a bad year. We didn't have any engines. Well, we had the tunnel-port engine, which was a disaster. The tunnel-port engines were built by Ford in Dearborn and shipped to us in a crate. We were not allowed to open the crate without a Ford engineer present. If an engine blew - and the engines blew every time we ran them - it went back in the crate and back to Ford. In 1967, we built our own engines and had not one failure. In 1968, we used Ford's engines and had failures at every race. It was very frustrating".
He later went on to say:
".....even though our paychecks came from Shelby, we felt we were Ford employees. We had Ford engineers working right with us in the Shelby shop. Whenever there was a failure, the Ford guys would run to the phone and call their boss. If the engine failed, the engine engineer would call the engine vice-president and say, "The engine failed, but it was the transmission's fault".
"If the transmission failed, the transmission engineer would call the transmission vice-president and say, "The transmission failed, but it was the engines fault!" We all thought it was pretty funny. But of course, since nobody from Ford ever admitted there was a problem, no problem ever got fixed. So that was kind of sad".
So, reading what Spencer said, it sounds like Shelby were caught in typical large corporation politics, where the right hand doesn't know what the left is doing, and everyone is guarding their own back. Whether Shelby's own guys could have got the tunnel-port motors to run reliably will never be known.