advancing a camshaft
the 477 and 475 superduty ford engine is the same engine. in 1970 the 477 specs were 253 hp @ 3400, and 415 fp @ 2000. in 1975 the 475 specs were 203 hp @ 3400 and 341 fp @ 2600. I assume the cam is retarded. my question is, how much? the cam is gear driven,110 teeth on the cam, and 55 teeth on the crank.
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Re: advancing a camshaft
well, I advanced the cam 1 tooth, and advanced ignition timing a few degrees. seems to run better. I think it is running a little lean, but will wait til I get electronic ignition before I play with jets. might even consider hho instead of jets.
Re: advancing a camshaft
A whole tooth is quite alot of advance, but if it cost you nothing but gaskets and your time, and works better, you are doing good, sir.
Re: advancing a camshaft
actually, 1 tooth equals 6.5 degrees. one nice thing about gear driven cam instead of chain. I bought an electronic ignition conversion kit on ebay, and am waiting for it to get here. pulling the backhoe, I am doing good to get 3 mpg with this beast. anything I can do to get more power without losing mpg will help. some of the hills I have to climb can take 30 minutes or more. less time spent pulling a grade means less fuel burnt. the compression on this engine is around 7.5, so a turbo or blower would be nice, but too expensive.
Re: advancing a camshaft
Well, at least you've done your homework. 6.5 degrees is really not that much... Not as much as a chain tooth would be. IIRC, I read somewhere that the emissions era timing sets are 10 degrees retarded on a Chrysler V8 (Hot Rod, or Car Craft, I think).
Does anyone make a cam for that series of motor? 204/214 (at .050") cams are great for any stock application. I picked up power and mileage with a simple summit 204/214 cam in a 350, as well as a 305.... And your motor was designed to run at 500-2000 RPM (designed for torque). What a wakeup a cam would be for your engine.
If you can't find an aftermarket cam, CamKing from SpeedTalk will hook you up (regrind yours)... Heck, he could recommend a grind for you better than me...... [url]http://www.jonescams.com[/url] IIRC, his name is Bill.. (I am crazyman at SpeedTalk)
Just remember, every engine is "JUST AN AIR PUMP" and that the cam determines it's personality, as do many factors.... The cam is the most important, though... Everything else can be worked around, yet the cam controls the airflow, when to flow it, and the optimum driveability RPM.............
I'd be willing to bet that there are Chevy equipped 502 crate motor's running around that are getting at least 6 MPG fully floored, just because it's a toy.........................................
Re: advancing a camshaft
the limiting factor for this engine is it's 3400 rpm redline. this engine throws rods at high rpm. I don't take it over 3000 rpm. it seems to run best around 2500 rpm. you mentioned earlier about it only costing me a set of gaskets. A gasket set costs 200.00, so I reused the crank seal, and siliconed the cover :D
Re: advancing a camshaft
[quote="mikehallbackhoe"]the 477 and 475 superduty ford engine is the same engine. in 1970 the 477 specs were 253 hp @ 3400, and 415 fp @ 2000. in 1975 the 475 specs were 203 hp @ 3400 and 341 fp @ 2600. I assume the cam is retarded. my question is, how much? the cam is gear driven,110 teeth on the cam, and 55 teeth on the crank.[/quote]
Hi,
My first post here... IIRC, horsepower measurement methods changed in 1972 from gross bhp (SAE) to net power. This could be the reason behind the big discrepancy between the specs. At that same time, emission regulations were beefed up, and drops in CR were how the manufacturers responded in efforts to comply, along with the attendant retarded timing. regards, nick
Re: advancing a camshaft
[quote="OlNick"][quote="mikehallbackhoe"]the 477 and 475 superduty ford engine is the same engine. in 1970 the 477 specs were 253 hp @ 3400, and 415 fp @ 2000. in 1975 the 475 specs were 203 hp @ 3400 and 341 fp @ 2600. I assume the cam is retarded. my question is, how much? the cam is gear driven,110 teeth on the cam, and 55 teeth on the crank.[/quote]
Hi,
My first post here... IIRC, horsepower measurement methods changed in 1972 from gross bhp (SAE) to net power. This could be the reason behind the big discrepancy between the specs. At that same time, emission regulations were beefed up, and drops in CR were how the manufacturers responded in efforts to comply, along with the attendant retarded timing. regards, nick[/quote]
In my opinion, the CR is probably the biggest difference.
My dad's '71 Ford 400 had 400 ft-lbs at 2500 rpm but the '72 only had 250 ft-lbs. CR went from 10:1 in '71 down to 8.5:1 in '72. I know of many 460s from '73 on that were 8:1 or lower that would get out-pulled by an earlier inline 300-6.
Re: advancing a camshaft
I agree compression plays the biggest part, but in my case ,the compression was always low, 7.5 to 1. even if my cam wasn't retarded, advancing it was a good move, since I don't use the top rpm anyway. the truck seems to run better with the cam advanced, but part of that is me getting used to driving the truck, figuring shift points, and so on. one nice thing about it is the lowend torque. you can bring it to a stop on a hill, and get back up to speed. Bad part is that speed is not very fast. I have added electronic ignition, advanced the cam, and still get 3 mpg. I am hoping hydrogen will help.