Rebuilding engine

[Brian Kulis]

Have a 72 Convertible, 302. It is all stock, original carb and everything. Engine runs great, does not seem to be any major issues, but freeze plugs are rusted and leaking. I am going to pull engine and replace all gaskets and seals. I want to "hop" up the engine a little bit. I don't want a quarter mile car, just a Classic with some pep!

My old 1960's "motorhead" Father In Law suggests a hotter cam, new carb and intake, headers and new duals to replace my rusted ones. He also suggest a heavier duty oil pump. I already have replaced coil and points with The Petronix system. Replaced all belts and hoses and rewired. Want to rebuild the engine and repaint it and engine area. Any Suggestions on the above, what size cam and carb or brands that you like and what you would do to add some horsepower, would be appreciated.

 

[johnwanzel]

From my experience, shop around for a reputable machine shop to handle rebuilding your bottom end. New pistons, rings, bearings, timing chain, and oil pump along with all the appropriate gaskets and seals. I personally like the edelbrock power packages. It's dyno proven performance and it takes the guess work out of what works with what. They even tell you how much horsepower to expect. I don't think you could go wrong with that. It all depends on your budget.

 

[cazsper]

What would you like from your car when you're done? If just a cruiser, something like 218/226 @ .050" should be nice. It would have a little rumble but nothing you wouldn't like driving every day. If you're going for a new rotating assembly, consider a 331 stroker. Inexpensive and it will give you a little more torque for a heavy car. As for a carb, a 600cfm with vac 2ndaries is plenty. For an intake, I like the Edelbrock Air Gap.

 

[Tubo]

If you doing a rebuild.

It is time to either, use a roller lifter block, or at least do a roller conversion. A hop up by using newer technology.

Modern oil formulations do not contain the levels of zinc a flat tappet cam needs for lubrication. Roller lifters allow cam profiles with agressive valve opening rates and yet a more gradual valve closing. Comparitively boosting performance of even moderate duration and lift roller cam profiles. In effect you have a cam with the performance of 8-15 degres greater duration of a flat tappet. The broader surface of a flat tappet prohibits any of these modern cam profiles from being utilized. So if your doing a rebuild any way, why give away efficency & performance. Alternately using a lower mileage roller block can allow you to just replace the "short block" and not have to do a full rebuild. I feel this is a concept a lot of the folks, who reccommend rebuilding a flat tappet block, have yet to grasp.

 

[mdan575]

If you doing a rebuild.

It is time to either, use a roller lifter block, or at least do a roller conversion. A hop up by using newer technology.

Modern oil formulations do not contain the levels of zinc a flat tappet cam needs for lubrication. Roller lifters allow cam profiles with agressive valve opening rates and yet a more gradual valve closing. Comparitively boosting performance of even moderate duration and lift roller cam profiles. In effect you have a cam with the performance of 8-15 degres greater duration of a flat tappet. The broader surface of a flat tappet prohibits any of these modern cam profiles from being utilized. So if your doing a rebuild any way, why give away efficency & performance. Alternately using a lower mileage roller block can allow you to just replace the "short block" and not have to do a full rebuild. I feel this is a concept a lot of the folks, who reccommend rebuilding a flat tappet block, have yet to grasp.

What he said. If you go out and look for a 1996 Explorer 5.0 you will get a nice roller motor with the GT40 heads(if you want to stay with iron heads). They are all over scrap yards here in my area with various mileage. 1997 and after had GT40P heads which are good heads but require special headers due to spark plug angle. I am also a big fan of the Edelbrock Power Packages(Top End Kit). You can get a nice performing motor at a reasonable price from a power package with a reasonable amount of weight loss in the aluminum heads and intake. IMO reasonable power for a DD/Cruiser with modern improvements. Something our big body cars can really use. They simplify what can be a complicated process for the average guy.

 

[woodsnake]

Don't forget, that if you go with a cam that is too big of a change, you will also have to change the rear gears and torque converter, as well as plan a brake upgrade.

I think you will be OK if you stay under .500 lift, just for a quick reference number....But talk to your father in law about the whole package, as it all needs to work together. Heads, cam, intake, transmission and rear gears.