Hey, people. As of late, I have been dealing with engine performance issues in my 1983 Jamboree. Good old Mabel is running a California spec. Ford 460. I live in Ca. so I spoke with a local star certified SMOG shop about increasing power output and got some great news that I think is worth sharing.While California SMOG requirements really limit your ability to increase engine performance, my old girl does NOT have catalytic converters and the air injection is not in the manifolds. The air is injected through the head, directly into the exhaust port. That means two GREAT things!1.) I can add any kind of headers and be smog legal, so I ordered a set of Hedman headers and will be wrapping them with a blanket. That will reduce radiant heat.2.) If I really want to improve performance, I can remove the heads and have the exhausts ported. The stock heads gain something like a 20% increase in exhaust flow when you port them.I can do both of the above, pass smog with no problem and definitely will see gains in engine performance and reductions in heat transfer to the cabin.A well know upgrade for a 460 is installing a 0 degree cam gear setup. However, I need to find out if modern fuels would allow me to still pass the sniffer test with the 0 gears installed. If I could do all three things above, I might pick up more than 100 HP. It's too bad I can't change the carb. too.At any rate, I will update this thread as things move forward.Jose

I spent nearly $5000 in trying to upgrade my engine and succeeded in going up a 6% grade at 45MPH instead of 35MPH. I would have rather had the $5000.Now I just sit back and enjoy the scenery running by at 45MPH.And by the way the gas mileage went from 7MPG down to 6MPG after the upgrades.

Interesting real world experience, Bear. Less mileage would suck!The write ups you see in places like 460ford.com say the changes I mention above should result in increased efficiency of exhaust scavenging. That increased flow is supposed to result in leaner carburetor settings, more complete combustion and better fuel mileage.Exactly what upgrades and parts did the $5k include?Jose

Banks is the only setup I know of that is CARB compliant for the ford van chassis

Jose,FL no longer has an emissions test. When we had an '83 E350/460, I replaced the timing set at around 95,000-miles thinking I'd find it shot. It wasn't but I installed a new set with all-metal sprockets including 0* crank sprocket. At a later time, I installed a FlowMaster "cat-back" exhaust. The part number did not go as early as 1983, probably because 1983 did not have a catalytic converter. A little A-Dapting got it installed, and the extra piece of straight 3" pipe that FM provided for longer wheelbases was all I needed to make up for the length of the cat that wasn't there. It was a 3" mandrel-bent aluminized exhaust that exited behind the passenger rear dual tires. Came out the correct length for the widened body and had a 4" polished stainless tip. All I really needed to get was a 2-1/2"by3" adapter to go from stock crossover to FM's 3" pipe.I ran an air intake from the radiator support direct to the stock air filter with 4" flexible dryer hose. With those few changes it ran VERY well and power was never an issue. I had tried Headers on a Dodge van we had years before and didn't want to cope with the heat again.Speaking of Headers, you don't want "Shorty" headers for high HP at RPM. You want Long Tube for low-end torque. Doug Thorley Tri-Y was a popular header for Class C. I believe Thorley may have become part of Summit Racing.

Banks is great gear, but really expensive and they don't make a system for an 83.Maybe the system from an 87 would work? Although the ones I have seen are 8-2-1 and my RV has a dual 4-1 system with an H crossover pipe.I poked around j-d. I was able to find a set of Hedman long tubes for $215. I should have them by Tuesday. Now the big challenge will be removing the old manifolds with the rusted on bolts. I already replaced the passenger side bolts and ended up with one sheared flush to the block. I used a gasket and high temp. RTV to seal it, but I know it's just gonna blow out eventually.Since the shop would charge me $600+ (barring a sheared bolt) to pull the manifolds and since I can use headers, I am just going to grind off the remaining bolt heads from the driver's side (I already took out three)and cut up the manifold if need be. That will leave me with the bolt bodies sticking out of the block. Then I will be able to get some heat and PB blaster directly to the threads and (hopefully) get the remaining bolts removed cleanly.I will take another look at that bolt stuck in the passenger side. I might take it in and have the shop try to get it out. If they say the head has to come off, then I might just have them pull both heads and go for the exhaust side porting.Jose

Ford 460 power increase - california smog legal

DaHose
Explorer
Sep 22, 2014
Mileage didn't really change, it's still 6-7 (ouch). The way she ran and the power when climbing felt good. To be honest, she hasn't run great since purchased, so any improvement at all would really be noticeable. I really want to change the cam gear, but I need re-assurance it will pass the damned smog. If it does, then maybe next year I'll pull the heads and un-shroud the exhaust ports. That would finish opening up the exhaust and really make her breathe/run well.

Yes Tvov, we have to smog anything older than 1975. Back before 2000 (IIRC) it was a rolling 25 year window, but since then it became locked in to only 1975 or older. Way sucks.

Jose
Tvov
Explorer II
Sep 22, 2014
So California requires vehicles that old to go through emissions testing? In Connecticut (unless they changed it again, which wouldn't surprise me...) vehicles 25 years or older are exempt from emissions testing.
j-d
Explorer II
Sep 22, 2014
Jose, Glad to hear good results! Do you feel you actually gained something on the Power or Fuel fronts?
I had learned about Zero Degree as an aside in an exchange with an OP on another forum years ago. Our 460 had nearly 100,000 miles when we got it and I thought the OEM timing set (especially if it had nylon sprocket teeth!) could be worn out. Somehow, if I remember right, I'd found a water pump bolt stuck in the timing cover. Something like that, anyhow. I decided to replace Water Pump and Timing Set on a pre-emptive basis. The work was a lot like what you said about camber plates... Lots of labor but not all that tricky.
We ended up with Rebuilt Molly Carb (that Ford/Holley), Steel Timing Set with Zero Crank Sprocket, OEM Exhaust Manifolds and Crossover, No Cat (not OEM on a 49-state E350 in 1983), and Flowmaster 3-inch single exhaust with "Big Block" muffler. It started well, ran strong, got about 8-mpg best. You've solved the piston-driven A/C compressor issue ours had.

EDIT - I should add that FL had emissions testing which has since been completely discontinued. But when they did, anything built on or after emissions systems came into effect had to test and pass. Year model was around 1973 if I recall. VERY difficult to get older vehicles to pass, even if the system hadn't been "tampered."

And Jose, the Timing Set was actually in good condition. Nylon cam sprocket looked good, chain not stretched, retarded sprocket just broken in.
DaHose
Explorer
Sep 22, 2014
Back from the weekend trip. Old Mabel ran great and was reliable. The doghouse temps. were way down, although there is still a lot of heat making its way up to the floor just behind the doghouse. I think I might want to use the remaining wrap and completely cover the headers all the way back to the collector end flange. Power was good and noise was not any louder than with the stock manifolds.

In all, I recommend the Heddman headers and I highly recommend the header armor product. I found a pair of pliers crimping closed my charcoal canister. When I return that, I will ask again about the 0 degree cam gear set.

Jose
DaHose
Explorer
Sep 19, 2014
I have an update.

First off, my smog guy told me that because all the smog ports and fittings are in the block/heads, that I can use any headers I want. WOOHOO!! I went online and bought a set of Hedman headers off of Amazon for $275.

Next, I had to remove the old manifolds. I managed to grind off all the old bolt heads with a long neck, electric die grinder. I cut off pieces of the manifold as I went using my angle grinder with cutoff wheels. That was fine as I am switching to headers and scrapping the old manifolds was acceptable to me.

The headers fit great, but the passenger side won't fit the factory metal heat shields that protect the spark plug boots. When I took it in for smog, the shop really recommended doing something about heat management as the new headers get glowing hot from the rich exhaust. To fix the head issue I bought some Heatshield Products Header Armor. It works GREAT! I can hold my bare hand an inch or so away from the header pipes. I couldn't do that with the old manifolds, so I expect the temps. under the doghouse to be much lower.

Now that the carb. was redone and the headers are on, old Mabel is running smooth and strong. We go on a trip this weekend and I will update with post voyage feedback.

Jose
Hank85713
Explorer
Jul 22, 2014
JosA look here and then at the redline link they are calif based:

http://www.search.com/search?q=ford+460+throttle+body+fuel+injection
DaHose
Explorer
Jul 22, 2014
I love the idea of changing to a maintenance free setup like a TBI and I already run an electric fuel pump.

I have looked before, but I can't find anything that is Ca. smog legal for my '83 engine. Do you have links to any that are CARB certified, Hank?

Jose
Hank85713
Explorer
Jul 22, 2014
jos a, most of the kits sold are carb approved and some of the companies are in kalif! They are expensive but the results would be better than a new carb setup IMO. I went with a edelbrock manifold and holly 650 dual pumper on my old ford 400 and got nothing better than I had with the 2 barrel carb. I also converted to electronic ignition and that helped more than anything.

I just did a search for 'ford 460 throttle body conversions' and had a bunch of links. If nothing else take a look at them. One sid it had the throttle cable designed to fit in the valley to simplify install. Anyhow was just a thought.
DaHose
Explorer
Jul 22, 2014
I'll see about a re-curved dizzy next, Fred. If I could still pass smog, that would be a super simple install.

I'm carbureted Hank, but in Ca. you CANNOT alter your carb. Although what I have read so far says that IF I could really do what I want, I would do the following.

Change the carb. to an Edelbrock 750, port the exhaust of the stock heads, install a 0 degree cam gear kit and fit headers. I understand that could give upwards of 300 HP and as much or more torque.

Change pistons to increase compression and you could be looking at close to 500 HP.

Jose
4K-Ranch
Explorer
Jul 22, 2014
DANG, got my eye on this topic, just got an '85 E350 with 460. Did a fresh rebuild on the carb and got more power, hehe, but never enough.

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Ford 460 power increase - california smog legal

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