Camshaft/Spring problem
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Senior User
Joined: Jun 2008
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From: Bozeman, MT
Camshaft/Spring problem
I have a 79 ford f-150 with a 400 that my uncle and i recently did some work to. we installed the edelbrock performer package which comes with a camshaft, lifters, manifold, and carb. This kit however did not seem to give me any more power or gas mileage. recently my engine starting making a ticking noise that speeds up with the rpm's. I was also recently told that if I didn't change the factory valve springs, they would not work with the new camshaft. I have not changed the springs and am wondering if this is the cause of the noise and if it could be robbing me of power as everyone on here says a cam carb and manifold are the best and easiest ways to up your power. thanks in advance
Posting Guru
Joined: Oct 2005
Posts: 1,017
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From: Longwood, Fl
Look at your instruction sheet closely. If your aftermarket cam has a lift that is too much, the stock valve springs will coil bind, which can cause big problems. Bent pushrods, broken pushrods etc.
The 400's uses exaust valve rotators, which are extra thick retainers that allow the exaust valve to rotate slightly at each lift. Those thick retainers take away from the maximum lift that can be used. You can probably replace the rotators with regular retainers and be O.K. You can use one of those compressor adapters for the spark plug hole and not have to pull a head.
We had that problem with a 79 bronco, bent pushrods and even caused some valve float, which bent a valve head.
Do a search, there was a thread on that subject recently and someone gave the figures that are the max lifts the stock setup will take. If not that, you may not have set the lifter pre-load correctly. Several things to consider there (pushrod length for one, depending on what all you did to the heads) LOL
The 400's uses exaust valve rotators, which are extra thick retainers that allow the exaust valve to rotate slightly at each lift. Those thick retainers take away from the maximum lift that can be used. You can probably replace the rotators with regular retainers and be O.K. You can use one of those compressor adapters for the spark plug hole and not have to pull a head.
We had that problem with a 79 bronco, bent pushrods and even caused some valve float, which bent a valve head.
Do a search, there was a thread on that subject recently and someone gave the figures that are the max lifts the stock setup will take. If not that, you may not have set the lifter pre-load correctly. Several things to consider there (pushrod length for one, depending on what all you did to the heads) LOL
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Senior User
Joined: Jun 2008
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From: Bozeman, MT
the camshaft is an edelbrock P/N 350-2172 with the following specs:
<table border="1"><tbody><tr><td>Valve Lift:</td><td>.484'' Intake / .510'' Exhaust</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Lobe Separation Angle:</td><td>112°</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Open/Close @.050'' Cam Lift:</td><td>Intake - 5° ATDC (opens) / 29° ABDC (closes)
Exhaust - 44° BBDC (opens) / 10° BTDC (closes)</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Duration Advertised:</td><td>282° Intake / 292° Exhaust</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Duration @ .050'' Lift:</td><td>204° Intake / 214° Exhaust</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Valve Lift:</td><td>.484'' Intake / .510'' Exhaust</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Lobe Separation Angle:</td><td>112°</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Open/Close @.050'' Cam Lift:</td><td>Intake - 5° ATDC (opens) / 29° ABDC (closes)
Exhaust - 44° BBDC (opens) / 10° BTDC (closes)</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Duration Advertised:</td><td>282° Intake / 292° Exhaust</td></tr></tbody></table>
<table border="1"><tbody><tr><td>Duration @ .050'' Lift:</td><td>204° Intake / 214° Exhaust</td></tr></tbody></table>
Senior User
Joined: Apr 2004
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From: Eastern Ohio
CAUTION!
Stock intake valve springs go solid (coil bind) at 0.490" valve lift. The stock springs on early non-rotating exhaust valves allow the same lift as the stock intake valve springs, but the springs on the later rotating exhaust valves go solid at just 0.480" valve lift. That is less lift than many popular performance cams provide, even the milder ones like the Edelbrock #2172 (0.484/0.510 gross lift) and the Comp Cams 255DEH (0.469/0.505 gross lift). Using the stock rotating exhaust valve springs and retainers with either of those cams will cause bent push rods.
This a quote from "Bubba's M Block Workshop"
Your springs are going solid.
Stock intake valve springs go solid (coil bind) at 0.490" valve lift. The stock springs on early non-rotating exhaust valves allow the same lift as the stock intake valve springs, but the springs on the later rotating exhaust valves go solid at just 0.480" valve lift. That is less lift than many popular performance cams provide, even the milder ones like the Edelbrock #2172 (0.484/0.510 gross lift) and the Comp Cams 255DEH (0.469/0.505 gross lift). Using the stock rotating exhaust valve springs and retainers with either of those cams will cause bent push rods.
This a quote from "Bubba's M Block Workshop"
Your springs are going solid.
Lead Driver
Joined: Nov 2000
Posts: 6,640
Likes: 349
From: Albuquerque
You might also have pushrod length problems and even hold the valves open which would also burn valves.
Your valve train geometry and measurement become extremely important with a performance cam on this series engine.
Your valve train geometry and measurement become extremely important with a performance cam on this series engine.
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