Will Stock Valve Springs handle a cam?

Posted By: EV2RUNNER

Will Stock Valve Springs handle a cam? - 04/26/10 02:53 PM

Im thinking of putting a cam in the 360 in my truck, it has 308 heads with stock springs and retainers. I dont have much cash so was thinking on cam and lifters as opposed to springs and retainers too. The cam is a Comp 268 Grind heres the specs

Basic Operating RPM Range 1,600-5,800
Intake Duration at 050 inch Lift 224
Exhaust Duration at 050 inch Lift 230
Duration at 050 inch Lift 224 int./230 exh.
Advertised Intake Duration 268
Advertised Exhaust Duration 280
Advertised Duration 268 int./280 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.477 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.480 in.
Valve Lift with Factory Rocker Arm Ratio 0.477 int./0.480 exh. lift
Lobe Separation (degrees) 110
Intake Valve Lash 0.000 in.
Exhaust Valve Lash 0.000 in.
Grind Number CRS XE268H-10

Thanks

Posted By: 4BBodies

Re: Will Stock Valve Springs handle a cam? - 04/26/10 03:14 PM

I always replace the springs, with a new cam it is cheap insurance. But if you want to use your old ones, the biggest thing to check for is coil bind. If you were using a cam with .5 inch lift I'd say no, but you might get away with it with the cam you picked. I think I paid around $50 for a set of Engle springs for my 340, and so far so good. It runs excellent, and revs just fine.

Posted By: Mopar_Country

Re: Will Stock Valve Springs handle a cam? - 04/26/10 03:15 PM

That camshaft will require some head work, as well as different springs and adjustable valve train. I just put this cam in my 318
http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=619&sb=2
it works very well and I think it will work for you as well. You can buy the kit for just over 300.00 which will include the cam, lifters, springs and retainers, and locks. The kit also has a new timing chain and gears. I would recommend that kit instead of just replacing the cam. Your stock valvetrain will work. Be sure of which way you take the rockers and bar off as they are specific, for oiling purposes.

Posted By: MoparforLife

Re: Will Stock Valve Springs handle a cam? - 04/26/10 03:28 PM

Use the springs that are rated for the cam. Also a lot of 360's have rotators on the exhaust valves further limiting the amount of cam that can be safely used because they shorten the installed height and travel of the valve. Get rid of the rotators and use a regular retainer just like the ones on the intake valves.

Attached picture 5947838-Rotator.jpg

Posted By: patrick

Re: Will Stock Valve Springs handle a cam? - 04/26/10 03:40 PM

use comp #901 springs and stock non-rotator retainers...should add another $60 to the price....

while it's apart, it's smart insurance to replace the t-chain, too...

Posted By: patrick

Re: Will Stock Valve Springs handle a cam? - 04/26/10 03:45 PM

Quote:

That camshaft will require some head work, as well as different springs and adjustable valve train. I just put this cam in my 318
http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=619&sb=2
it works very well and I think it will work for you as well. You can buy the kit for just over 300.00 which will include the cam, lifters, springs and retainers, and locks. The kit also has a new timing chain and gears. I would recommend that kit instead of just replacing the cam. Your stock valvetrain will work. Be sure of which way you take the rockers and bar off as they are specific, for oiling purposes.

no it doesn't...all it needs are stock rockers, locks, retainers and comp #901 springs.

if it's a stock long block 360 with low comp, and in a heavy vehicle, like a truck typically is, I wouldn't go bigger than an XE262. if it has a low stall converter, don't go bigger than an XE256.

Posted By: MoparforLife

Re: Will Stock Valve Springs handle a cam? - 04/26/10 03:58 PM

Quote:

Quote:

That camshaft will require some head work, as well as different springs and adjustable valve train. I just put this cam in my 318
http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=619&sb=2
it works very well and I think it will work for you as well. You can buy the kit for just over 300.00 which will include the cam, lifters, springs and retainers, and locks. The kit also has a new timing chain and gears. I would recommend that kit instead of just replacing the cam. Your stock valvetrain will work. Be sure of which way you take the rockers and bar off as they are specific, for oiling purposes.

no it doesn't...all it needs are stock rockers, locks, retainers and comp #901 springs.

if it's a stock long block 360 with low comp, and in a heavy vehicle, like a truck typically is, I wouldn't go bigger than an XE262. if it has a low stall converter, don't go bigger than an XE256.

I agree with you Patrick. Have seen a lot bigger more aggressive cams with out any additional head work other than some decent springs.If much over 500 lift a trim on the guides but that is nothing scientific and cam be done at home as long as you use regular umbrella valve seals

Posted By: Dodgem

Re: Will Stock Valve Springs handle a cam? - 04/26/10 04:21 PM

Why not go this route
http://www.summitracing.com/parts/CCA-K20-223-3/

Posted By: MoparforLife

Re: Will Stock Valve Springs handle a cam? - 04/26/10 06:21 PM

BTW pictured is the partial results of using a .474 lift cam with stock springs and rotators. also took blew out a head, cam, hole in block, and couple bent rods.

Posted By: 69L78Nova

Re: Will Stock Valve Springs handle a cam? - 04/27/10 02:26 AM

I ran a MP509 with stock 587s for a LONG time with no problems whatsoever

Posted By: MoparforLife

Re: Will Stock Valve Springs handle a cam? - 04/27/10 02:49 AM

Quote:

I ran a MP509 with stock 587s for a LONG time with no problems whatsoever

Some people get lucky. You also must have found one without rotators. No way that it would have gone with rotator retainers.

Posted By: 69L78Nova

Re: Will Stock Valve Springs handle a cam? - 04/27/10 03:15 AM

No, it did not have rotators

Posted By: moper

Re: Will Stock Valve Springs handle a cam? - 04/27/10 11:04 AM

No, you need springs to match the cam as mentionned...

Posted By: dustergirl340

Re: Will Stock Valve Springs handle a cam? - 04/27/10 11:37 AM

Get the springs. Do it right or don't do it at all. You know this hobby ain't cheap.

Posted By: Mopar_Country

Re: Will Stock Valve Springs handle a cam? - 04/27/10 03:13 PM

I misspoke when I said it required head work. What I meant to say, to clarify, that some work will need to be done to the heads as in springs, locks etc. Comp cams DOES recommend running an adjustable valve train with the XE268H

[7] Stock springs cannot be used.

[23] Includes special shafts & spacers.

[37] Adjustable valve train required.

I would suggest calling comp cams tech line for your peace of mind. You certainly don't want what you see in the pic's posted here in your day.

Posted By: Scojodak

Re: Will Stock Valve Springs handle a cam? - 04/27/10 03:25 PM

As mentioned several times, get the rated springs for the cam. Even if you dont bind the springs, you'll be asking why there's no performance gain because the valves are bouncing off the seats at 5000 rpm. Just my $.02

Posted By: HotRodDave

Re: Will Stock Valve Springs handle a cam? - 04/27/10 05:29 PM

Funny you mention 5000 rpm because I put an XE268 in a 360 with stock springs when I was younger and 5000 was like a rev limiter kicked in, I even tried shimming the springs to virtual coil bind and it would not do noticably better, when I put in good springs it was fine to 6000, and just smoothly lost power instead of all the popping and crap with the stock springs. It had ported 302 heads on it and made great TQ.

Posted By: EV2RUNNER

Re: Will Stock Valve Springs handle a cam? - 04/28/10 02:48 PM

Quote:

BTW pictured is the partial results of using a .474 lift cam with stock springs and rotators. also took blew out a head, cam, hole in block, and couple bent rods.

Valve Springs suddenly look very CHEAP After viewing this pic...My Mind's made up Thanks all!