66 327 2bbl to 4bbl cam change needed??? - Chevelle Tech
Chevelle Tech join team chevelle as a supporting member  
Chevelle Parts at SS396.com      
GROUND UP & SS396.com         
Official Sponsor of Team Chevelle
     

Auto Insurance

Chevelles.com is the premier Chevrolet Chevelle Forum on the internet. Registered Users do not see the above ads.
Engine AdvertisementGeneral Engine Discussion.

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old Nov 5th, 11, 11:53 AM
magna19 magna19 is offline
Tech Team
Jerry
 
Join Date: Jul 2006
Location: Guthrie,Ok
Posts: 104
Default 66 327 2bbl to 4bbl cam change needed???

i have a 66 327 2bbl (pwr-pak heads no acc holes) motor was in the car when i got it. Has a serpentine (one) belt system and I am in need of acc holes to mount alternator better. I have a deal on a set new in the box 12558060 vortec heads with rocker arms for 500.00 If put a set of 12558060 vortec heads and aluminum dual plane intake with edelbrock 600 cfm , will I need to do a cam change to match the new stuff, What will performance be if I dont change cams. The deck numbers are gone and I am 99% sure by casting numbers/date codes the motor is 185 base hp truck version.
__________________
1966 Chevelle 2Dr Coupe 327 Auto
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old Nov 5th, 11, 12:37 PM
Mike Mike is offline
Lifetime Premium Member
& Moderator
 
Join Date: Apr 2005
Location: North America
Posts: 14,630
Default Re: 66 327 2bbl to 4bbl cam change needed???

Assuming your correct on your 185hp ,you do have a mild cam but it's the same cam as the 66 4bbl cam and actually the same as the 350/300hp -GM p/n 3896929
Yeah ,there are better cams out there but it's likely the 8.75:1 c/r that'll hold you back.
__________________

Reply With Quote Quick reply to this message
  #3  
Old Nov 20th, 11, 7:03 PM
BigEd36 BigEd36 is offline
Tech Team
Ed
 
Join Date: Mar 2010
Location: Auburn, IN
Posts: 33
Default Re: 66 327 2bbl to 4bbl cam change needed???

Quote:
Originally Posted by magna19 View Post
i have a 66 327 2bbl (pwr-pak heads no acc holes) motor was in the car when i got it. Has a serpentine (one) belt system and I am in need of acc holes to mount alternator better. I have a deal on a set new in the box 12558060 vortec heads with rocker arms for 500.00 If put a set of 12558060 vortec heads and aluminum dual plane intake with edelbrock 600 cfm , will I need to do a cam change to match the new stuff, What will performance be if I dont change cams. The deck numbers are gone and I am 99% sure by casting numbers/date codes the motor is 185 base hp truck version.
By looking at the '66 327 specs on the GM Heritage Center archives, the cam is a single pattern grind and has .3987 lift on both intake and exhaust, and it's definitely a very mild cam (the 350 300HP cam didn't come out til '67, when the 350 became available). It would not have to be changed to work with the Vortec heads, but I believe a cam change to a more modern grind would be beneficial.

According to the specs I've found for the '66 truck 327 the CR (compression ratio) is only 8 or 8.5:1 with flat top pistons, purposely kept low to deter detonation in a truck engine pulling hard. With flat top pistons Vortec heads will usually give a CR about 9:1 or a little more, so I believe you'll pick up a little compression. The Vortec heads have much better flow than your present heads, but they do seem to like cams with a little more exhaust duration (like the 350 300HP cam) because the intakes flow comparatively better than the exhausts. Stock Vortec heads are limited to .475" lift without modifications to allow higher lift. Many recommend a .450" lift limit. With the increase in compression and better breathing, combined with the upgrade to an aluminum dual plane manifold and 600 cfm carb, I believe you'll pick up 40-50 plus HP over what you have now, it will make a big difference. But I believe you would maximize your HP gain by going to a "split pattern" cam with a little more exhaust duration (even tho I love single pattern cams). Something like the Summit K1102 would work well. It's Summit's version of cam that many consider an "RV" cam, with a mild increase in lift and duration over the "stock" cams for an increase in HP and torque with strong lowend and will tow well. Specs are .420/.442 lift (intake/exhaust), 262*/272* advertised duration, 204*/214* at .050" duration, 112 LSA. Cam/lifter kit is $99.95 at www.summitracing.com. This cam will idle as smooth as stock and keep you under .450" lift on both intake/exhaust.

Summit's K1103 is a step up, it's Summit's version of the cam GM Performance Parts uses in the 350HO 330 HP crate engine and the "602" 350 350HP sealed circle track engines that come with Vortec heads. Specs are .442"/.465" lift, 272*/282* advertised duration, 214*/224* duration at .050", 112* LSA. It's also $99.95 at Summit Racing. This cam will give a mild, but noticeable idle, and still have great street manners (good idle, good vacuum for power brakes, and will work with a stock torque converter).

If you would want to upgrade to a little more "modern" grind but stay with "stock" specs, the Summit K1101 is Summit's version of the 350 300HP cam (again $99.95 for cam/lifter kit), with a few thousandths more lift, and (I believe) a couple degrees smaller LSA, so it might be a little "torque-ier" than the stock 350 300HP cam, but little difference.

Something to think about: Even if you didn't plan on a cam upgrade, with the engine far enough apart to change to the Vortec heads and intake, it will be little more $$$ and work to change the cam/lifters.

Ed
__________________
When the greenflag drops the BS stops!

Check out my website at: Ed Eldridge's Race Page
Reply With Quote Quick reply to this message
  #4  
Old Nov 20th, 11, 9:16 PM
grovey grovey is offline
Senior Tech Team
Tim
 
Join Date: Jul 2005
Location: pa
Posts: 1,363
Default Re: 66 327 2bbl to 4bbl cam change needed???

sounds like a good swap to me. i'd use a thin head gasket, and low lift rule cam on a 108 in there. should really wake it up.
Reply With Quote Quick reply to this message
  #5  
Old Nov 21st, 11, 1:07 AM
BigEd36 BigEd36 is offline
Tech Team
Ed
 
Join Date: Mar 2010
Location: Auburn, IN
Posts: 33
Default Re: 66 327 2bbl to 4bbl cam change needed???

Grovey, I thought about suggesting a lift rule cam, but most lift rule cams will have enough duration to really start giving up streetability, and I didn't know if magna19 would want to go that route. Figuring 7cc for flat top valve reliefs, "stock" .025" deck height, .015" thick 4.1" bore head gasket (FelPro #1094) and 64cc Vortec heads yields about 9.4:1, so long duration cams will be counterproductive. One cam I like that would work well with Vortecs is the Crane Energizer 274HO6, or the versions from Summit (supplied by Crane) and the Elgin E1785P, all the same specs. .450" lift, 274* advertised, 218* @ .050", 106* LSA (it's basically a comp 268H with a 106* LSA). Works well with today's compression ratios and gives a nice "rump rump" at idle but very streetable. Shaun's Nova in this clip is a stock Goodwrench 350 with Performer intake and 600 cfm Holley.
__________________
When the greenflag drops the BS stops!

Check out my website at: Ed Eldridge's Race Page
Reply With Quote Quick reply to this message
  #6  
Old Nov 21st, 11, 1:50 AM
novaderrik novaderrik is offline
Senior Tech Team
Derrick
 
Join Date: Feb 2002
Location: Howard Lake, MN, USA
Posts: 17,028
Default Re: 66 327 2bbl to 4bbl cam change needed???

while you've got the top end of the engine off, look at the cam lobes.. if they are shiny and flat, you might as well swap a mild cam in it..
__________________
"Detroit hasn't felt any real pride since George Bush went to Japan and vomited on their auto executives, I tell you whut"

-Hank Hill
Reply With Quote Quick reply to this message
  #7  
Old Nov 29th, 11, 6:58 PM
magna19 magna19 is offline
Tech Team
Jerry
 
Join Date: Jul 2006
Location: Guthrie,Ok
Posts: 104
Default Re: 66 327 2bbl to 4bbl cam change needed???

Thanks for all the info on cam choices. I have decided to do a cam change also. Havent got the top off yet but that is coming soon. Also has a 2400 stall, MSD dist. and 6al box, manual brakes, pwr steering. What HP will these vortec heads at 9 to 9.5 compression and an L79 spec cam with 650-750 edelbrock carb do. The 185 hp 2bbl setup it has now was figured on a 16.10 @ 80something mph the previous owner did at the track. I would like to end up with a 350hp L79 type motor.
__________________
1966 Chevelle 2Dr Coupe 327 Auto
Reply With Quote Quick reply to this message
  #8  
Old Nov 29th, 11, 8:32 PM
MrBill66Malibu MrBill66Malibu is offline
Senior Tech Team
Bill
 
Join Date: Aug 2005
Location: King NC via Long Island NY
Posts: 3,783
Send a message via AIM to MrBill66Malibu
Default Re: 66 327 2bbl to 4bbl cam change needed???

You should see around 300-350hp and 350 torque according to CamQuest6
__________________
Bill
385
4 speed M20
3:42 posi
1/8 mile 8.6 @ 84mph not too impressive LOL
http://s71.photobucket.com/albums/i1...libu/Chevelle/
Reply With Quote Quick reply to this message
  #9  
Old Nov 29th, 11, 10:09 PM
novaderrik novaderrik is offline
Senior Tech Team
Derrick
 
Join Date: Feb 2002
Location: Howard Lake, MN, USA
Posts: 17,028
Default Re: 66 327 2bbl to 4bbl cam change needed???

Quote:
Originally Posted by magna19 View Post
Thanks for all the info on cam choices. I have decided to do a cam change also. Havent got the top off yet but that is coming soon. Also has a 2400 stall, MSD dist. and 6al box, manual brakes, pwr steering. What HP will these vortec heads at 9 to 9.5 compression and an L79 spec cam with 650-750 edelbrock carb do. The 185 hp 2bbl setup it has now was figured on a 16.10 @ 80something mph the previous owner did at the track. I would like to end up with a 350hp L79 type motor.
why stick with the L79 cam- that's 45 year old cam technology.. you can get a more modern cam that will put those vortec heads to better use at the upper end of the rpm band with better driveability and efficiency down low..
__________________
"Detroit hasn't felt any real pride since George Bush went to Japan and vomited on their auto executives, I tell you whut"

-Hank Hill
Reply With Quote Quick reply to this message
  #10  
Old Nov 30th, 11, 7:30 AM
magna19 magna19 is offline
Tech Team
Jerry
 
Join Date: Jul 2006
Location: Guthrie,Ok
Posts: 104
Default Re: 66 327 2bbl to 4bbl cam change needed???

Novaderrik Im not stuck on the L79 cam, just want an aggressive sound without spinning to 6000 rpm, the motor is of somewhat unknown condition, other than calling Comp Cam and asking I dont know alot about cams. What was you reccomending.
__________________
1966 Chevelle 2Dr Coupe 327 Auto
Reply With Quote Quick reply to this message
  #11  
Old Nov 30th, 11, 1:47 PM
novaderrik novaderrik is offline
Senior Tech Team
Derrick
 
Join Date: Feb 2002
Location: Howard Lake, MN, USA
Posts: 17,028
Default Re: 66 327 2bbl to 4bbl cam change needed???

if you just want that lumpy idle and want it to still be easy to drive, then get one of the "Thumpr" cams.
just call a few cam companies and see what they say.. call each one a few times- call, get a recommendation, hang up.. call again and hopefully talk to someone else at the company and see how closely their recommendations line up.
then come back here and listen to the real experts..
__________________
"Detroit hasn't felt any real pride since George Bush went to Japan and vomited on their auto executives, I tell you whut"

-Hank Hill
Reply With Quote Quick reply to this message
  #12  
Old Nov 30th, 11, 3:40 PM
magna19 magna19 is offline
Tech Team
Jerry
 
Join Date: Jul 2006
Location: Guthrie,Ok
Posts: 104
Default Re: 66 327 2bbl to 4bbl cam change needed???

Thats how i did my big block motors. I was happy but wish i would have went with a bigger cam after the fact. Always ends up that way, start out lumpy sound then wanting 800hp on the street. LoL
__________________
1966 Chevelle 2Dr Coupe 327 Auto
Reply With Quote Quick reply to this message
  #13  
Old Nov 30th, 11, 8:16 PM
grovey grovey is offline
Senior Tech Team
Tim
 
Join Date: Jul 2005
Location: pa
Posts: 1,363
Default Re: 66 327 2bbl to 4bbl cam change needed???

why not upgrade the springs for 100 bucks ? put a 60103 voodoo in it. this is a 327 after all. that short stroke 327 will like rpms. your gonna give up some lowend grunt compared to a 3.48 or 3.75 stroke based sbc. gotta spin it a lil man...
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply
Chevelle Tech > Mechanical > Engine      Current Topic: 66 327 2bbl to 4bbl cam change needed???
Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 8:57 AM.


Is there a site like this for?    El Caminos Camaros Novas Impalas GTO Chevy Punch All Chevys

2009 Team Chevelle - AutoForums