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In the Dec. '04 issue we answered a question regarding some disappointing power figures for an upgraded 390 Ford FE engine. We offered advice on checking the ignition advance curve, because the '63 engine had been fitted with a mid-'70s truck distributor, and then talked about verifying the compression ratio, as Edelbrock aluminum heads had been installed. One aspect of this combination we completely overlooked was the intake manifold. In describing the engine combination, the writer mentioned that it was running an old Edelbrock Street Master manifold, and since some of us were too young to recall these '70s smog-era pieces (which are no longer produced), the assumption was made that it was a garden-variety dual-plane design. In fact, some Edelbrock personnel informed us that it was a single-plane with exceedingly small runner cross-sections intended to boost torque for RV-type applications. We're told this intake is all done by 4,500 rpm, so it's entirely possible that the 390 is being choked now that it has significantly increased airflow capacity thanks to the new Edelbrock aluminum heads. Edelbrock goes on to recommend that an upgrade to even the base Performer dual-plane would probably have a significant effect on the 390's output. Edelbrock also offers a Performer RPM for the FE Ford, but the tech staff felt the regular Performer would suit this particular engine well.
Tuning by Rebuilding
My brother-in-law has a '68Camaro that he purchased a couple months ago. He called me this morning to tell me he had taken the car to Union Grove, the local quarter-mile, for open race day. Last fall he bought his wife an '04 Cobra convertible, which she dearly loves and drives in nice weather. They, along with their son, ran the two cars with some embarrassment for dad. It seems sonny drove the Cobra to a 14.2 his first time with severe axle hop. Dad took a shot and eased off the line to a 13.6 at 104 mph. Well the Camaro ran a big 15.8, smokin' out the tailpipes, much to his wife and son's embarrassment. My brother-in-law was devastated and now wants to rebuild the engine. I asked how bad it smoked and all his wife would say was that it was the only car doing that all day and it looked awful. Shouldn't a car like that run low 13s all day long? He's determined to do a major rebuild, which I believe he should but with care.Tom KinneyLake Villa, IL
Before your man rips into that engine, he should take steps to determine its actual condition. It's a good bet that the smoke coming from the Camaro wasn't necessarily an indication that it's time for a rebuild, but rather an indication of a bad tune-up or some other less serious problem. These days, 35-plus years after they were built, first-gen Camaros that are in nice shape (as your brother-in-law's appears to be from your photo) are that way because they've either been meticulously cared for or restored; the days of good-looking but worn-out original '67-'69 Camaros has pretty much passed. For that reason, it seems unlikely that an example as clean as your brother-in-law's would have an engine that was so wiped out that the ring seal would be wasted, unless the problem is that the engine was poorly built during its last rebuild. Of course, there is the chance that a rebuild is in order, but the point here is that you should determine to some degree of certainty whether or not a rebuild is required before tearing it down.