Hi, I am a professional certified mechanic, with an engineering background, and 35+ years experience. I will do my best to assist you. Also keep in mind I don't know if you are a pro or a novice, so feel free to add any additional info at any time.
That sound doesn't sound good, but it might be distortion from a particular style of microphone, wind, or even a frequency the mike picks up too good. But it could be what it sounds like. I like the exhaust tone, the mellow, slightly loud tone is great.
The engine..............well if you consider this truck was really designed to motor around with a torquey low power six, this engine is a beast. But as far as hot 350 engines go it is mild.
If you have any serious performance goals it will need a lot of structural work. A Mustang IFS front suspension is a step in the right direction as far as design, but remember a Mustang II is a Ford Pinto with different sheet metal. They are real popular with drag racers because they are light. And street rodders like them because they became madly popular, and inexpensive driven by the drag racer demand. It isn’t a heavy duty suspension, so use the tubular steel A frames for strength, and it will work great. The aftermarket Mustang II IFS setups are higher strength that the original parts, so that is a big plus. Just stay away from stock A frames, and components, if you do that it is a good upgrade for this truck. The cost is all over the place, speedway motors is a great source, a link for them HERE. You can pretty much count on spending 2 K (or more) on parts, then there is the install. You can tie up 4 to 6K in a hurry if you go with the best, XXXXX XXXXX it installed. If you have deep pockets, or if you can install it yourself it is particularly attractive option.
The high CG (center of gravity) is the tough one, if it is running hard with a hot motor and it gets out of shape around a corner, you want to keep it shiny side up. Lowering it helps with the high CG, you can get drop spindles on the Mustang IFS setups. Also front and rear sway bars, and a decent power steering setup help a lot. When you add a hot engine, you have to beef up the brakes, so don’t loose sight of that.
The steering can be tightened up if the steering box is a little loose, but if the looseness is from wear then it cant be adjusted out. I would ask him “With all the work done to this truck, why would a small adjustment be something that wasn’t done” I have heard it needs a little adjustment a lot when the adjustment wasn’t the problem, so be ready for that. That might not be the case, still it happens a lot.
As far as power in 79 there were two different 350 engines offered in the 49 state cars, no 2 barrel engines were made. The engines offered were the LM=1 with 170 HP, and the Z-28 with 175 HP. These engines had very small cams, and lean fuel mixtures. The heads were not to good for performance. The compression was very low too, about 8.2 to one. It is pretty easy to get 300 HP out of them, you need different heads, cam intake and carburetor to do this. All in all you can really make this truck great, it is a little pricy, it looks like a good foundation to start with, if you can get it for a good price. Go over all of this and if you have any more questions at all, I am here to help. Good luck with it, have a great day, and Thanks for using Just Answer.
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