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454 Camshaft Choice? Decisions Decisions!
I think my 1973 Chevy C20 454 needs a new camshaft and I can't decide which one to buy. I drive my truck maybe twice a week with an occasional trip to the dump. The 454 is stock and I'd like a little bit more power but I don't want to make the mistake of buying a "thumper cam" when I just need one a little above stock specs! Can someone explain "lift & duration" to me in laymen's terms?
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Re: 454 Camshaft Choice? Decisions Decisions!
There's not really any simple way to explain camshaft dynamics or any real way to compare
I'm not sure if you got rid of that cast iron intake yet but that right thee is killing as much power as a cam swap would facilitate For cams there are two different durations that you typically see, adv duration and adv duration at .050 lift. The later is used industry wide (almost) to compare camshafts. Lift is simply that lobe lift and lift at the valve. There are extensive online articles that go into detail and explain everything much better and since I don't feel up to the task of typing two pages (yes two pages) I will leave it up to you and google. That said what your looking for is an RV style cam. Like a comp 260. You can also call individual cam company's and they will spec a camshaft for you based off what you want and what your setup is. This is the more recommended route since you will always be sure you got the best matched cam for your needs. My recommendations bullitt cams, isky cams, crane cams, lunati cams, Howard's cams and last but least comp cams. In that order. You will also likely need matching valve springs and new pushrods and long slot rockers depending on the lift. A lot of people run stock valve springs and do just fine but I don't like 30+ year old worn valve springs on any engine. |
Re: 454 Camshaft Choice? Decisions Decisions!
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Re: 454 Camshaft Choice? Decisions Decisions!
Call any cam manufacture.
Give them what you're doing they can spec a nice cam |
Re: 454 Camshaft Choice? Decisions Decisions!
If the engine is totally stock, there are several things you can do to increase power and mileage, whereas all a bigger cam will do in a stock engine is suck more gas and reduce vacuum. That said, some of the newer cams, like a mild Lunati Voodoo, can increase torque and horsepower with no ill side effects. But you will need to start with the items below.
2.5" low restriction dual exhaust properly operating heat riser valve, if equipped optimum ignition timing curve ensure any emission control systems are operating correctly Maybe a 570-670 CFM Holley or 600-650 Edelbrock carb on a modern Weiand or Edelbrock dual plane intake manifold. (Unless your carb is a Q-jet in good shape.) And this isn't 100% necessary, but you might want to do a little cylinder head work -- 3-angle valve job, heads surfaced to bump compression a little, and new stock replacement valve springs, or perhaps one step up from stock. Have fun. |
Re: 454 Camshaft Choice? Decisions Decisions!
I won't chime in on selection, you can read for a month and still not know much. Like already mentioned, you can call the manufacturers and get recommendations straight from them. (you can get an idea just browsing catalogs and checking rpm range recommended...)
MikeB also brings up a good point in making sure your other systems are up to the task and functioning properly. Your 40 yr old valvesprings should be changed out also, again the cam manufacturer can make a recommendation based on the cam. Educate yourself on break-in procedure! Unless you want to pony up the $$ for a retrofit roller... |
Re: 454 Camshaft Choice? Decisions Decisions!
Just a bit more than stock? Try the Lunati 60200 cam. I'm quite pleased with mine.
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Re: 454 Camshaft Choice? Decisions Decisions!
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Re: 454 Camshaft Choice? Decisions Decisions!
Most sites give you an RPM range and intended usage guideline. If that doesn't make you feel at ease, the larger parts warehouses have technical staff that can help you make your selection based on other vehicle specs that effect cam choice (gears, stall speed, vehicle weight, etc). Summit, Jegs, PAW all have these people on staff. Personally I really have had good luck making the most HP per $$$ with the Summit Racing brand of camshafts. For your basically stock truck, I'd stick with the 1300 or 1301 kit with lifters for $109.97.
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Re: 454 Camshaft Choice? Decisions Decisions!
BBC Camshaft Part Numbers
Part # Year Type Lift Dur @ .050 lift Comments/Specs/RPO's/Apps 340282 Solid .560I/.560E Lift .262I/.262E 121 deg overlap, competition-short track apps 353040 1973-74 Hyd .440I/.440E Lift .210I/.210E production Corvette 3863143 1965-71 Solid .520I/.520E Lift .242I/.242E See Note 1 3883986 1965-72 Hyd .460I/.488E Lift .213I/.217E See Note 2 3904362 1965-71 Solid .520I/.520E Lift .242I/.242E See Note 3 3925533 1965-69 Solid .540I/.560E lift .262I/.269E 133 deg overlap, 427 L-88, Reverse rotation 3925535 1965-69 Solid .540I/.560E Lift .262I/.269E 133 deg overlap, 427 L-88, standard rotation 3959180 1969-70 Solid .560I/.600E lift .262I/.273E 135 deg overLap, 427 ZL-1, 454 LS-7 3994094 Solid .600I/.600E Lift .286I/.286E See Note 4 6272989 Hyd .500I/.500E Lift .222I/.221E 121 deg overlap, marine grind or HP street 14096209 Hyd .500I/.500E Lift .222I/.221E 121 deg overlap, marine grind or HP street (6272989) Note 1: 80 deg overlap, 396 375hp L-78/L-89, 427 425/435hp L-71/L-72, 454 450hp LS-6, HP street Note 2: 396 325/350hp L-34/L-35, 427 385/390/400hp L-36/L-68, 454 345/360/390hp LS-4/LS-5, good torque/HP Note 3: 80 deg overlap, 396 375hp L-78/ L-89, 427 425/435hp L-71/L-72, 454 450hp LS-6, HP street Note 4: 148 deg overlap, maximum power with F.I. or tunnel ram, Can Am I like 353040 1973-74 Hyd .440I/.440E Lift .210I/.210E production Corvette -- or 3883986 1965-72 Hyd .460I/.488E Lift .213I/.217E See Note 2 |
Re: 454 Camshaft Choice? Decisions Decisions!
I had a 73 454 C20 with a bad cam - lobes wore out and crushed the pushrods, etc. So, I just had a stock cam installed. As I recall, early 454s had "soft" cams from the factory and many needed replacing. I have an 83 C20 454 (with a granny 4 spd, not a turbo 400 like the 73.)
That 73 454 with a turbo 400 was the fastest vehicle I have ever owned, including my 63 SWC corvette. So, I don't know why you would need a fancy cam, unless you plan to race that beast. My 83 would be fast but the granny keeps the acceleration down. I am not interested in speed - just reliability. If you use your VIN to search for a stock cam from GM you may find that your stock engine had an "RV" cam, especially if you have a camper special like my 83, so that is the way I would go. |
Re: 454 Camshaft Choice? Decisions Decisions!
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Lunati... or give Bullet Racing cams a call (no they are not just for racing)... they have all the Ultradyne grinds, tell them what you are looking for and they'll steer you right |
Re: 454 Camshaft Choice? Decisions Decisions!
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Re: 454 Camshaft Choice? Decisions Decisions!
Here is an example of a camshaft that will work well in a stock engine and meet your goals:
http://www.summitracing.com/parts/hr...make/chevrolet |
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