Shopteacher

Hi there! I teach a small vocational and business education class at an alternative high school. We do a lot of field trips and service projects, so a while back, I requested that the school provide my class with a van. Since part of our program includes small engine repair, they decided that we could use the old spare van that was sitting behind the maintenance shop. I don't know how they figured that a 460 was a small engine!
Anyway, to make a long story short, we took it from a gassy, smoky, barely running beast that got 3 mpg to a decently running beast that gets 7.5 mpg on a good day. We did a full tune up with spark plugs that are one range hotter than stock. We also replaced the stock 4bbl carb with an Edelbrock unit and made the adjustments using a vacuum gauge. We checked through the vacuum lines and replaced a few of them. It runs much better now but still idles rough and just doesn't seem to have the power that I would expect from a big-block. There certainly isn't any budget to replace the van, so are there any ideas for better performance?

atec77

Run it on Lpg

KILLERME

check leads,, and mechanical Advance not siezed, ignition timing etc,, should have 34deg at 3000rpm . spray carb clean around carb base and intake mating surfaces to see if have vac leaks, it will idle up if it has. high octane fuel.

390wagon

remember a 460 built in 82 is no fire breather to begin with, probably wheezes out 200hp or less brand new.

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68 Ford Country Sedan Wagon-390 FE, C6, 9 Inch
87 Chevy Caprice Classic Wagon-307, 2004R, 10 Bolt, what can i say, i grew up with that car

Paul Kane

By 1982, the 460 was smothered in emmissions control features and this dramatically affected performance.

I imagine that pulling the engine or swapping the heads is not an option. Assuming this is the case, then you need to recurve the factory distributor for a more agressive advance curve. The oem 1980's 460 dizzy has virtually no advance to speak of (for emissions reasons) and so the engine has downright lazy performance.

Also, the 1972-up carburetted 460's have a timing chain and gears that effectively retard the cam timing by 4 degrees. An aftermarket timing chain for the pre-1972 engines will correct this.

If pulling the heads is an option, then porting the exhaust side will help immensely. The D3VE casting heads have terrible exhaust flow characteristics and choke down the big 460. The freer flowing ported exhaust will help measurably. By the way, that engine has only about 7.8:1 compression ratio, which doesn't help either.

You may also switch to a 1968-1970 head which will increase your compression ratio to about 9:1. 1968-1970 valve train is also required with these heads. Porting the exhaust is still a necessity on these heads.

Start with the dizzy & timing chain. If you want to go further, then we can supply you with the ported heads if that's not a particular area you wish to venture.

Paul

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Shopteacher

Thanks for the input! Budget is very limited so heads are not an option for the time being. The school will not allow me to purchase higher octane fuel although I did try a little out of my own pocket and it did make a noticeable difference. We have considered replacing the timing chain- that is really good to know about the pre-'72 chain. I take it this can be installed with no changes to the crank and cam?

If it were up to me, I'd push the 460 over the hill. I once had a '79 Ford F-150 with a 351 modified and a really lousy 2bbl carb that would outperform this van on all fronts.

Paul Kane

The pre-1972 camshaft timing chain and gears will bolt on without any issues. Be sure that you buy the straight up timing set and not the retarded timing set. Some aftermarket double roller chains are available either way (such as the Cloyes, which offers a double-roller in Pre-72 & post-72 versions).

If you cannot recurve the distributor, then twist it over a bit (advance the ignition timing). Note that this approach will affect your idle speed and may make the starter motor have to work harder to turn the engine over.

In regards to the ported heads, the point I am making is that, yes, while porting helps any set of factory heads and offers some improvement, the case for the 429/460 engine family is so godawfully bad that the engine can barely breathe at all with the as-cast heads. In other words, I am not suggesting that you hot rod this engine and "port the heads, man!", I am specifically stating that these particular iron heads have horrible flowing exhaust ports as-cast and that this is a big part of the Van's problem....and why the 351 F150 walks away from the 460 van. Grind the exhaust and the 460 will be transformed a la Jekyl & Hyde. But the other bolt on replacements (noted above) will help notably.

Paul

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