03-04 exhaust cams to replace intake cams?

[376shovel]

Hey dudes I'm grabbing an 05 motor to replace my ticking engine, and it will be on the stand for a few weeks before it goes in. Anybody out there use an exhaust camshaft on the intake side for more power? Looks like the 96-98 Cobra intake cams are hard to come by, but these cams are cheap and plentiful. I'm a GM guy so I don't know much about the 4.6 DOHC specifically, but as long as they're the same journal size and there are no issues with the sprocket, I dont see why you couldn't use an exhaust cam on the intake side. Thanks.

[RubberCtyRauder]

an 05 motor from what?

[376shovel]

an 05 motor from what?

Lincoln Aviator

[MOTOWN]

Hey dudes I'm grabbing an 05 motor to replace my ticking engine, and it will be on the stand for a few weeks before it goes in. Anybody out there use an exhaust camshaft on the intake side for more power? Looks like the 96-98 Cobra intake cams are hard to come by, but these cams are cheap and plentiful. I'm a GM guy so I don't know much about the 4.6 DOHC specifically, but as long as they're the same journal size and there are no issues with the sprocket, I dont see why you couldn't use an exhaust cam on the intake side. Thanks.

Exhaust cam used in place of intake cams please tell me your not serious

[376shovel]

You must be misinterpreting. I'm not saying switching them. I'm saying buying additional exhaust cams. So the motor would go from 184/196 duration (intake and exhaust respectively) as it comes from the factory, to 196/196 duration. I see people using Cobra intake cams from 96-98 or 99-01 cobras and they're not much more duration, but a whole lot harder to come by. This would be a cheap, almost as good option. I just don't know if there are any actual physical differences between the design of an intake/exhaust cam in these engines.

[Spectragod]

Hold my beer......watch this...

[Marauderjack]

Hold my beer......watch this...

Me too!!

[376shovel]

Do the lobes line up? I'm assuming it won't work physically by the reaction I'm getting. It'd be nice to know why, being as I have said I don't know much about this engine, but I guess I can take the hit and stop posting anything on this board and just use the search function. Matter of fact I don't know why the moderators don't just lock down the board entirely and use it as a library.

[FordNut]

Do the lobes line up? I'm assuming it won't work physically by the reaction I'm getting. It'd be nice to know why, being as I have said I don't know much about this engine, but I guess I can take the hit and stop posting anything on this board and just use the search function. Matter of fact I don't know why the moderators don't just lock down the board entirely and use it as a library.

I don't know any reason it wouldn't work, you would have to get ARP cam bolts and either completely eliminate the keys from the gears or use the early gears with removeable keys.

You would have to index them with tooling to hold the cams in place until the gear bolts are tightened. The positions of the key wouldn't be useful for indexing, you would just have to use the degree wheel and dial indicator to position them. It takes a long time to index the cams in these engines, but I figured it out ok.

[FordNut]

Passenger intake and passenger exhaust should have a specific offset between lobes on every cylinder. Passenger exhaust and passenger exhaust should have a different offset but every cylinder would be the same. Remove the key and rotate the cam for the correct lobe separation and it should work.

Keep in mind, the passenger and driver sides are different so you gotta have two passenger exhaust on the passenger side and likewise on the driver side.

[WPG_Merc]

[376shovel]

Passenger intake and passenger exhaust should have a specific offset between lobes on every cylinder. Passenger exhaust and passenger exhaust should have a different offset but every cylinder would be the same. Remove the key and rotate the cam for the correct lobe separation and it should work.

Keep in mind, the passenger and driver sides are different so you gotta have two passenger exhaust on the passenger side and likewise on the driver side.

Interesting. Thanks, FordNut. Sounds like it isn't done often, I'm just planning for when I have it on the stand and I have to check the engine out anyway. I was planning on degreeing the stock cams, never done it on one of these engines. Never even popped a cam cover on one so this is the kind of info that helps big time.

[martyo]

Being different can get expensive.

[FordNut]

Being different can get expensive.

^^^^^^^^
What he said

[FordNut]

Interesting. Thanks, FordNut. Sounds like it isn't done often, I'm just planning for when I have it on the stand and I have to check the engine out anyway. I was planning on degreeing the stock cams, never done it on one of these engines. Never even popped a cam cover on one so this is the kind of info that helps big time.

Degreeing is a slow process, for sure get the ARP bolts. The OEM bolts are TTY and they aren't rated for near the torque the ARP bolts are. When I was degreeing my cams I figured out the tightness of the bolts is what holds the gear in place, not the key. The keys were filed down enough that they weren't even touching the cam grooves when I got done. Adjustable aftermarket cam gears may be another option where by some chance a key could be installed.