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-   -   Stock CAM advance anyone? (http://www.jeepgarage.org/f183/stock-cam-advance-anyone-67365.html)

Kevman 10-31-2013 11:40 AM

Stock CAM advance anyone?
 
hi guys,

just wanted to findout if anybody has advanced a stock cam on a 4.7, & if so by how much & whats your opinion on the results.

cheers all!

Strongjeff 10-31-2013 06:03 PM

Re: Stock CAM advance anyone?
 
Quote:

Originally Posted by Kevman (Post 921406)
hi guys,

just wanted to findout if anybody has advanced a stock cam on a 4.7, & if so by how much & whats your opinion on the results.

cheers all!

hey bro, I have been wanting to do this on my 3.7 as well, im just worried if theres a woodruff key in the cam which would make this impossible. I thing its on the right head, the cam tone ring, you will need to rotate the cam without rotating the tone ring. remember, the crank and cam sensor must be in sync or the engine will not fire. I just haven't had the time to check it out myself. the army, and other projects and doing work on ppls cars on the weekends prevent me from doing this.

if you can get it sorted out, a great writeup would be great, I want to shift my powerband down some

thanks again

jeepgcoman 10-31-2013 08:42 PM

Re: Stock CAM advance anyone?
 
Come on guys, just do it....after doing a little research. I've done this to 3 vehicles now, all with positive results.

74 Chevy Nova, 250 cu. in. 6, advanced cam one tooth on cam gear, headers, Holley 500 CFM 4 barrel carburetor, close ratio 4 speed. It would routinely beat relatively stock small block V-8 Chevys and many other V-8's. I can't tell you how many times I had to pop the hood to prove to guys that it was a six. A fun ride.

06 Hemi WK, see mods. in signature. I advanced the aftermarket cam, which was already advance 4* by another 2* for a total of 6*. Take a look at some of the threads I've done on my mods., the cam advance and the results.

05 Hemi LX, modded almost exactly the same as the WK except I advanced the same aftermarket cam by 6* (total of 10*) after I saw how good it worked on the WK.

Here's a little chart that shows what happens when you change the cam timing:
Technical Specs & Information Pretty interesting stuff. Like I said, do a little research and then go for it. IMO, I wouldn't go less than ~6*. One tooth on the Hemi timing set is just under 7*, if that helps. There was a pretty big difference between the LX and WK, as far as low end performance goes. Also, be aware that you'll lose a little top end, but then again, how often do you drive around at 5000-6000 RPM.

Go for it!!

Edit: Kevman, yours is going to be a little different because of the two cams. I don't know how that is set up, but you'd for sure have to do both cams. Make sure you research it thoroughly before tackling it.

Kevman 10-31-2013 09:24 PM

Re: Stock CAM advance anyone?
 
Quote:

Originally Posted by jeepgcoman (Post 921721)
Come on guys, just do it....after doing a little research. I've done this to 3 vehicles now, all with positive results.

74 Chevy Nova, 250 cu. in. 6, advanced cam one tooth on cam gear, headers, Holley 500 CFM 4 barrel carburetor, close ratio 4 speed. It would routinely beat relatively stock small block V-8 Chevys and many other V-8's. I can't tell you how many times I had to pop the hood to prove to guys that it was a six. A fun ride.

06 Hemi WK, see mods. in signature. I advanced the aftermarket cam, which was already advance 4* by another 2* for a total of 6*. Take a look at some of the threads I've done on my mods., the cam advance and the results.

05 Hemi LX, modded almost exactly the same as the WK except I advanced the same aftermarket cam by 6* (total of 10*) after I saw how good it worked on the WK.

Here's a little chart that shows what happens when you change the cam timing:
Technical Specs & Information Pretty interesting stuff. Like I said, do a little research and then go for it. IMO, I wouldn't go less than ~6*. One tooth on the Hemi timing set is just under 7*, if that helps. There was a pretty big difference between the LX and WK, as far as low end performance goes. Also, be aware that you'll lose a little top end, but then again, how often do you drive around at 5000-6000 RPM.

Go for it!!

Edit: Kevman, yours is going to be a little different because of the two cams. I don't know how that is set up, but you'd for sure have to do both cams. Make sure you research it thoroughly before tackling it.

Jeepgcoman,

Thanks for the info, i have read your thread on the cam advance & its the inspiration to try it on mine. Like you said, i fully intend to go for it, but as its technically my moms daily driver, i literally got no room for error. hence the many annoying Q's :worried:

i have a fairly Noob Question: how do i determine which rotational direction will give a CAM advance vs CAM Retard?

jeepgcoman 10-31-2013 09:55 PM

Re: Stock CAM advance anyone?
 
Move the cam(s) forward in the direction of rotation. This will allow the intake and exhaust events to occur earlier (advanced) by the number of degrees you move it/them. Before doing it, count the number of teeth on the cam gear(s) and divide by 360. This will give you the number of degrees for each tooth of the gear. If the 4.7 has one cam (both intake and exhaust) for each bank, you'll have to advance both by the same amount. If it were a true dual overhead cam (one for intake, one for exhaust), like my old Mercedes, you could change them independently a number of different ways.

After you've done it, be sure to turn the engine over by hand to make sure there are no piston to valve clearance issues. On stock cams it should not be an issue unless you go maybe 2-3 teeth in either direction.

Strongjeff 10-31-2013 10:06 PM

Re: Stock CAM advance anyone?
 
the 3.7/4.7 are SOCH setups

jeepgcoman 11-01-2013 10:53 AM

Re: Stock CAM advance anyone?
 
That may be better for the advance job then. Is everything easy to get to, or do you have to take half the front of the vehicle apart to get to it.....like the Hemi? I would have pulled the WK apart again and advanced it to 6* like my LX, if it wasn't such a PITA to get the radiator/trans. cooler assy. out.

Strongjeff 11-01-2013 12:52 PM

Re: Stock CAM advance anyone?
 
Quote:

Originally Posted by jeepgcoman (Post 922003)
That may be better for the advance job then. Is everything easy to get to, or do you have to take half the front of the vehicle apart to get to it.....like the Hemi? I would have pulled the WK apart again and advanced it to 6* like my LX, if it wasn't such a PITA to get the radiator/trans. cooler assy. out.

should only need to pull the valve covers off, ive had them off before when I painted them, cam/chain/and gear are exposed. I just never got around to seeing if theres a woodruff key in the cam that lines everything up (cam/gear/and tone ring).

jeepgcoman 11-01-2013 01:53 PM

Re: Stock CAM advance anyone?
 
I can't comment on the 3.7/4.7's, as I am clueless on them, but it certainly can't be rocket science, and I would think that moving the timing gear forward one tooth wouldn't have anything to do with woodruff keys or timing marks. One mine, since I was installing new cams, I had to line all the marks up and go from there, but if yours has chain/belt tensioners (I am sure it does), you may be able to loosen them and move the cams. Just be careful not to lose track of where you are. I would mark everything (cam gears/chain) in their stock positions and then go from there. Also, be careful that the chain/belt doesn't move a tooth in either direction on the crank pulley. Again, not knowing the setup, you may be able to keep a little tension on the chain/belt coming off the crank (both sides) by wiring it in place or sticking something through a link that will keep it where you want it. I think, for me, movement on the crank gear would be the biggest concern, as everything else, from your description, appears to be easy to see and get to. How much does the timing cover(s) hide? Is it one big one, or are there more cover pieces like some ricers? Do these engines use belt(s) or a chain(s)?

Strongjeff 12-07-2013 01:47 AM

Quote:

Originally Posted by jeepgcoman (Post 922124)
I can't comment on the 3.7/4.7's, as I am clueless on them, but it certainly can't be rocket science, and I would think that moving the timing gear forward one tooth wouldn't have anything to do with woodruff keys or timing marks. One mine, since I was installing new cams, I had to line all the marks up and go from there, but if yours has chain/belt tensioners (I am sure it does), you may be able to loosen them and move the cams. Just be careful not to lose track of where you are. I would mark everything (cam gears/chain) in their stock positions and then go from there. Also, be careful that the chain/belt doesn't move a tooth in either direction on the crank pulley. Again, not knowing the setup, you may be able to keep a little tension on the chain/belt coming off the crank (both sides) by wiring it in place or sticking something through a link that will keep it where you want it. I think, for me, movement on the crank gear would be the biggest concern, as everything else, from your description, appears to be easy to see and get to. How much does the timing cover(s) hide? Is it one big one, or are there more cover pieces like some ricers? Do these engines use belt(s) or a chain(s)?

They use chains. But the system has a seperate tone ring from the gear. I fear there is a woodruff key keeping the two aligned. As far as how much is covered goes, 98% of the cam gear is exposed when the valve cover is off. Problem is getting to the tensioner down below it, so i could turn em one tooth. But its like im saying. If there is a key keeping the tone ring and gear aligned it would be pointless to try. Them cam and crank sensors on this engine have to be in sync or it wont start let alone run. When i get the chance ill get some pictures for you. Almost forgot. The 3.7 engines have 3 chains in them. One from the crank to the balance shaft. Then one from each head to the balance shaft. Its a some what complex setup with each chain having a tensioner

Strongjeff 12-14-2013 12:21 PM

its as i feared. I was up at the skills shop on post and there was a 3,7 grand up there getting new heads cuz of dropped valve seats. Anyway i got a look at them and there is a pin in the end of the cam that sticks out just over a quarter of an inch. So it looks like no cam advance for us soch V6/V8 guys

Galaxie500 12-20-2013 12:26 AM

Re: Stock CAM advance anyone?
 
Quote:

Originally Posted by Kevman (Post 921748)
Jeepgcoman,

Thanks for the info, i have read your thread on the cam advance & its the inspiration to try it on mine. Like you said, i fully intend to go for it, but as its technically my moms daily driver, i literally got no room for error. hence the many annoying Q's :worried:

i have a fairly Noob Question: how do i determine which rotational direction will give a CAM advance vs CAM Retard?

Makes no sense to advance our stock 4.7 cams, after market maybe, check out other 4.7 builds on this forum, your in for alot of work and $$$ with little gain, that's what and SRT8 is for:thumbsup:


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