.

Jump to content


Hello, Allpar Forums member or visitor! If you were an active member (more than two posts) or subscriber, you would not see this ad!

Register for a free account or Sign in (see top right of page for Facebook/Open ID login icons).


Photo
- - - - -

Replacing 318 Cam


This topic has been archived. This means that you cannot reply to this topic.
11 replies to this topic

#1 GoldDuster74

GoldDuster74
  • Inactive
  • 49 posts

Posted December 24, 2004 at 05:00 am

Hello again all,

Im planning on replacing the cam in my 74 Duster with a 318 in it, and I have a few questions on the whole subject. First off are the lifters mechalical or hydrallic, second will a used cam off of a 340 or 360 with a 4bbl carb work in my block and give me more of a advantage with my edelbrock intake and 4bbl carb or should I just go with a new edelbrock performer cam, third is there anything else I would/should replace (i.e. timing water pump in that area) when replacing the cam? Thanks for looking any advice will be greatly appreciated.

#2 KOG

KOG

    KOG

  • Active Member
  • 5,895 posts

Posted December 24, 2004 at 07:32 am

Cam is hydraulic lifter type. Do NOT use a 340 cam and you'd be much better using a new cam than a used 360 one as well. A Comp 252 H Extreme energy cam would work well. Too much cam will absolutely kill torque on the 318. A new double roller timing chain and new lifters are a must. You will need to degree the new cam when you install it. If any of this sounds like too much trouble or cost, then leave it alone. The stock cam will run better than a botched installation of a "better" one.

#3 Cudapete

Cudapete
  • Active Member
  • 3,965 posts

Posted December 24, 2004 at 09:31 am

The Edelbrock Perfromer cam is a mild street cam that is designed with the 318 in mind. Using a used cam can be risky. Since it is such a big job I would go with new. If you do go used you still need to use new lifters. Replace timing chain with a dual roller design and water pump while your in there.

Edited by Cudapete, December 24, 2004 at 09:32 am.


#4 USA-aok

USA-aok
  • Inactive
  • 483 posts

Posted December 24, 2004 at 10:38 am

I agree with both previous posts to a 'point'. That point is make only necessary improvements; don't 'cheap-out' but don't spend serious $ on a well-used engine.
If your 318 checks out okay after compression, oil pressure and vacuum tests, then go ahead and do the cam swap. In my opinion, there's nothing wrong with installing a (used) 340/360 cam IF there's nothing wrong with the cam itself. ALL the lobes and journals must be 'miked' to ensure that the lobe tips especially are not worn to any extent. This would be rare but not improbable.
Since installing new lifters is advised, again unless the used cam/lifters are near perfect and not mixed-up. Check the best price you can get on a (factory) 340/360 replacement kit from MP. It hs valve lifts of .429" and .444" and should be less than $200. This cam will still give you over 15 inches of vacuum at idle and there's no need to put on anything larger than the stock 2Bbl. unless you choose to do that later. The T-gears is a logical replacement since the old ones must be removed before the cam. Good luck and happy holidays.

#5 usdart

usdart
  • Active Member
  • 104 posts

Posted December 24, 2004 at 10:58 am

Hello again all,

              Im planning on replacing the cam in my 74 Duster with a 318 in it, and I have a few questions on the whole subject.  First off are the lifters mechalical or hydrallic, second will a used cam off of a 340 or 360 with a 4bbl carb work in my block and give me more of a advantage with my edelbrock intake and 4bbl carb or should I just go with a new edelbrock performer cam, third is there anything else I would/should replace (i.e. timing water pump in that area) when replacing the cam?  Thanks for looking any advice will be greatly appreciated.

<{POST_SNAPBACK}>


I bought a new cam and lifter set for under $100.00. from Summit, PN 6901.
It is in my 360 and I highly recommend it ! Smooth idle and loads of power and torque. My only problem is traction now.

#6 GoldDuster74

GoldDuster74
  • Inactive
  • 49 posts

Posted December 24, 2004 at 06:58 pm

Well the reason I want to replace it is because ive heard that it would be a great benefit for my 2bbl to 4bbl conversion on my 318. : /

#7 frankwest (converted)

frankwest (converted)
  • Guests

Posted December 24, 2004 at 07:38 pm

Just so you know, if you replace the cam with a larger grind you will need stronger valve springs.
Try a summit K6901 like USdart said and get some Comp Cams valve springs @ http://store.yahoo.c...mcamenhigp.html . You might as well replace the stock timing chain with a double roller while it's apart. http://store.yahoo.c...n273318340.html .

One thing leads to another so do it right the first time and you will save money in the end.
Have fun and don't forget to use decent gaskets and break in the cam before driving.

#8 GoldDuster74

GoldDuster74
  • Inactive
  • 49 posts

Posted December 24, 2004 at 09:08 pm

So the PN 6901 comes with the lifters? And if it does if I got that the springs duel timing chain and water pump i'd be all set for the replacemet correct?

#9 frankwest (converted)

frankwest (converted)
  • Guests

Posted December 25, 2004 at 10:56 am

So the PN 6901 comes with the lifters?  And if it does if I got that the springs duel timing chain and water pump i'd be all set for the replacemet correct?

<{POST_SNAPBACK}>



The cam kit comes with lifters. The water pump is up to you , but if it's the original I would change it . Summit sells a cam change gasket kit-PT# FEL-CK4015 .

Merry Christmas and Happy New Year !

#10 usdart

usdart
  • Active Member
  • 104 posts

Posted December 25, 2004 at 12:45 pm

Just so you know, if you replace the cam with a larger grind you will need stronger valve springs.
Try a summit K6901 like USdart said and get some Comp Cams valve springs @ http://store.yahoo.c...mcamenhigp.html . You might as well replace the stock timing chain with a double roller while it's apart. http://store.yahoo.c...n273318340.html .

One thing leads to another so do it right the first time and you will save money in the end.
Have fun and don't forget to use decent gaskets and break in the cam before driving.

<{POST_SNAPBACK}>

Yes, lifters are included...I would swap to a new oil pump too, just for insurance.

By the way, I really like that cam for a daily driver.

#11 GoldDuster74

GoldDuster74
  • Inactive
  • 49 posts

Posted December 25, 2004 at 03:36 pm

Alright everyone thanks for all your input it really has helped me a lot and Merry Christmas to all!!!! :D

#12 Webslinger60

Webslinger60
  • Inactive
  • 990 posts

Posted December 26, 2004 at 02:35 am

The new 4bbl manifold & carb will work with the original cam, but will definatley utilize more of their potential with a little more lift & duration.

The stock cam for an original '74 318-2bbl was 240/248-383/400. This is a really mild grind. (BTW, the 360-2bbl was 252/256-400/410 and would've run much better). The 340/360-4bbl (and some 318-4bbl's) was 268/276-429/444. This will work, but is a bit hot for a 318 with just a 4bbl upgrade. It would work better for with a manual trans, since the rpms, would rev higher when shifting. And definaltey headers.

For a former 318-2bbl with auto and iron manifolds, Id go milder. MP makes two nice cams for 2-to-4bbl swaps. The #759 is 260/268-430/450 and the #761 is 268/272-455/455. The #759 is a bit less duration than the 340 grind, but has more lift for lower rpm power. The #761 is a bit warmer.

The Compcams HE260 is 260/260-440/440 and the HE268 is 268/268-454/454.
Those are single pattern cams. Some say they're better, but the factory always used split pattern cams. The Comp XE256 is a nice in-between it's 255/268-447/455. But keep in mind it has a fast/steep ramp design. This means it opens the intake valve faster, holds it open longer, then slams it shut. An interesting design, but it absolutley requires good valvetrain parts. Decent lifters, Stiffer springs and HD rockers & rods, so they dont bend or poke through the rockers.
The XE might be too much for hi-mile, OEM valvetrain parts.

And also keep in mind, anytime you increase cylinder presuure (ie: more air/fuel)
you put more stress on the rings. I've seen older engines begin to burn oil & smoke after a cam change. Do a wet & dry compression check. If the compression rises much more than 10psi wet, then the rings are getting old, and a hotter cam could cause them to allow oil to pass-by.


.
Allpar

Home · Cars · Engines · Repairs · Tool and Car Reviews · News

Please read the terms of use and privacy policy. We are not affiliated with Chrysler Group, makers of cars, minivans, trucks, and Mopar (TM) parts. We make no guarantees regarding validity or applicability of information, opinions, or advice. Posts may be edited and used in other parts of allpar.com and affiliated car-related sites. We have the right to remove or modify any message, and to ban or suspend any user without notice. Logos and site-specific information copyright © 2001-2014 Allpar LLC; Chrysler PR materials remain property of Chrysler Group.