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Maddening Motor MountsI have a '67 Mustang with no motor or trans that I purchased several years ago. The car originally had a 289 and a manual trans, but I'm attempting to install a 351W and a C6 automatic. My problem is that when I tried to install the 351, I found that it would not sit in the engine bay squarely. I'm using new stock replacement 289 engine mounts and setting the motor on the factory frame brackets, but something is obviously wrong. I've inspected the frame and done some measuring, and there is no evidence of a previous front-end collision-the car seems to be square. I've checked several parts books and they all list the engine mount for the small-block V-8 to be the same from '67 to '69. I can't check the original engine mounts because I didn't get them with the car. I realize that the 351W is a taller-deck engine than the 289, but my understanding is that the lower portion of the block has the same dimensions, and that the 289 mounts should work fine. I have another '67 that now has a 302, and I seem to recall having a similar problem some years ago when I installed a new engine and tried to use new mounts. I wound up using the old ones in that case, but what is the deal here?Steve GregoryGreenwich, CT
We've heard of this problem before, as it has confounded Mustang modifiers for years. You're right about the parts book listings, most claim that the engine mounts are the same for '67 through '69 or '70, but as we've found, this is incorrect. Apparently, the '67 Mustang uses a one-year-only engine mount/frame bracket design, and as far as we can tell, there is not currently a replacement engine mount manufactured for this application. The lack of a proper replacement is likely due to the fact that the aftermarket believes the '67 is covered with existing offerings. Fortunately, there is a relatively simple way around this: Find a set of '68 frame brackets and bolt them in place of your original '67 brackets. This will allow the use of currently available engine mounts. The '68 frame brackets are not offered new, but should not be difficult to locate-any vintage Mustang salvage supplier should be able to assist you. As for the 351W, you're right about the lower portion of the block sharing dimensions with the standard Ford small-block. The Windsor should bolt right in with the replacement 289/302-style engine mounts once you swap to the '68 frame brackets.
Valvespring VerificationI have a '78 Z28 with a 350 four-bolt main block, 0.020-over flattop TRW forged pistons, cast crank, and stock rods. It has a 750-cfm double-pumper Holley mounted to a Victor Jr. single-plane intake feeding rebuilt 491-casting fuelie heads with Manley 2.02/1.60-inch valves. The valves are 0.100-over stock stems with Z28 springs and Crane Cams 1.6:1 roller rockers. The cam is a Lunati solid-lifter, with 308 degrees duration and 0.500-inch lift. A reworked HEI sparks through a set of MSD wires. All of this runs through a Muncie M20 and an 8.5-inch rear with 3.73 gears.
The problem is that the engine won't rev over five grand. I've changed distributors, and the fuel pressure sits at 5 psi at 5,000 rpm, so the spark and the fuel are there. My question is, did my head man make a mistake by putting the stock-type Z28 springs on the valves that are 0.100 inch longer than stock, making the spring pressure too light, or is there another problem? Mick PaffordPortage, WI