327 camshaft question? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 09-19-2009, 02:15 AM
Registered User
 
Last photo:
Join Date: Sep 2009
Location: new zealand
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
327 camshaft question?

Hi,am new here and wanted some help with my cam choice,have a 65 ss impala with 327,350 trans and 3-36 gears,has been running with wrong heads and today i finally scored a set of 186 camel humps with 2-02-1-60 valves,not easy to find here in new zealand,now i want to freshen the heads and change the cam as wanting more power up top,is running stock cam and 520 small valve heads,what camshaft should i run for good power and performance without going to high stall converter, was thinking comp 262 or 268, or summit 1103,any suggestions, have posted intro, cheers

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 09-19-2009, 06:40 AM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,654
Wiki Edits: 0

Thanks: 15
Thanked 58 Times in 55 Posts
The comp 268 magnum will give you a lopey idle without sacraficing low end torque which is ideal for a street machine. I would recommend a 2200 stall to help eliminate idle creep.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-19-2009, 01:57 PM
Registered User
 
Last photo:
Join Date: Sep 2009
Location: new zealand
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
would the comp 268 magnum give me better top end than the other comp 265 DEH cam, what do you think about the summit cams,better on price,are they good.thanks
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 09-19-2009, 02:32 PM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,552
Wiki Edits: 326

Thanks: 691
Thanked 877 Times in 745 Posts
"more top end" and "stock converter" are diametrically opposed. You can't have your cake and eat it too.

Any cam you bolt into the motor has an operating range of around 3500 rpm's. You can put that 3500 anywhere you want to....idle to 4200 or....1000 to 4500 or....1500 to 5000 or....2000 to 5500 or....2500 to 6000 or....3000 to 6500 or....3500 to 7000 or....4000 to 7500 or....well, you get the idea I'm sure.

As you move up in the operating range, the intake closing point on the cam moves further away from BDC and you make less and less cylinder pressure because as the piston comes up in the bore on the compression stroke, compression does not begin until the intake valve is closed. So, if you close the intake later, you have to raise static compression ratio to make up for the loss of some of the intake mixture being blown back up the intake tract by the ascending piston. Also, as you move up in the operating range, it takes more and more valve spring and associated parts to allow the tappets to follow the cam profile and close the valves properly without float.

On a more or less stock 327 with a stock converter, I would bolt in a CompCams XE262H and be done with it.

If you want more top end, you're going to have to start spending more money to change other components in the motor and also shell out for a looser converter and shorter (numerically higher) rear gear.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 09-19-2009, 03:05 PM
JeffB's Avatar
Registered User
 
Last photo:
Join Date: Jul 2006
Location: Phoenix,AZ
Age: 68
Posts: 1,644
Wiki Edits: 0

Thanks: 2
Thanked 77 Times in 70 Posts
Now the facts

The specs on the Comp Cams 265 DEH and the Summit 1103 are the same as are some other companies,there are generic grinds that several companies use it's all a matter of profit for them( you can always buy a Comp Decal) if you read the fine print on Comps website a lot of the cams recommended here so far do require you change springs and retainers also once you exceed .450" lift you should change rockers also.So,best bang for the buck: Summit K1103.Summit 141506,Summit 174000 for a good match for an intake the Weiand 8120.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 09-19-2009, 05:18 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,524
Wiki Edits: 0

Thanks: 2
Thanked 330 Times in 327 Posts
Quote:
Originally Posted by JeffB
The specs on the Comp Cams 265 DEH and the Summit 1103 are the same as are some other companies,there are generic grinds that several companies use it's all a matter of profit for them( you can always buy a Comp Decal) if you read the fine print on Comps website a lot of the cams recommended here so far do require you change springs and retainers also once you exceed .450" lift you should change rockers also.So,best bang for the buck: Summit K1103.Summit 141506,Summit 174000 for a good match for an intake the Weiand 8120.
Just so you know the Comp 265DEH and summit 1103 cam are not exactly the same. but they are similar. They do have the same peak valve lift but the duration @.050" seat duration and LSA are a bit different.
Similar purpose and basic rpm range. Slightly different lobe shape and valve timing.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 09-19-2009, 07:41 PM
Registered User
 
Last photo:
Join Date: Sep 2009
Location: new zealand
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ok,thanks for the info guys,am already running edelbrock performer intake ,eddy 600 carb and headers,with stock cam and 4520 small valve heads ,shift kitted turbo 350 trans i was running 15.5 at 89mph,the impala pulls from low and runs out at about 4500,was wanting to improve without too many changes,with getting the 186 heads with bigger vaves and better flow should improve,in two minds now about cam choice,my 186 heads have 7/16 studs and double springs ,i may consider a set of 1.6 ratio roller rockers and stick with the cam in it to improve lift and retain lower power,with the better heads do you think this will help my performance? cheers
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 09-19-2009, 07:49 PM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,654
Wiki Edits: 0

Thanks: 15
Thanked 58 Times in 55 Posts
I wouldn`t keep the stock cam, especially with upgraded springs on the heads. The 268 as I mentioned would work fine. If you already have headers and I sure hope you do then a single pattern cam like the 268 is all you need. Chevy heads have almost always had a very efficient exhaust port, the intake isn`t as great so there is no need for more lift and duration on the exhaust side. With the better heads you`ll see some gains with a stock cam but nothing like what you`ll see with a better cam. If the heads breathe better as the 186`s will then the cam will also. If you go with a new cam you`ll need to use valvoline racing oil for the break in and there after. If you use regular oil without Zinc and other anti wear ingrediants the cam will go flat. Since you`ve mentioned the heads have 2.02 valves I hope the chambers were unshrouded.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 09-19-2009, 08:10 PM
Registered User
 
Last photo:
Join Date: Sep 2009
Location: new zealand
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks,heads were off a dz302 engine z28,owner had decided to put alluminm heads on,use to run these with roler rockers hence the 7/16 studs,will take your advice and go with 268, cheers
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 09-20-2009, 08:32 AM
Member
 

Last journal entry: JB's 37 Pickup
Last photo:
Join Date: Oct 2002
Location: Smoky Mountains
Age: 76
Posts: 2,358
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Techinspector has thrown out some good stuff as well as others. I have done similiar to what you are attempting and there are a few things I will throw out for thought, even though you may have all ready made up your mind. You have an E-brock Performer intake which matches well with the smaller valve heads you have. Going with the bigger valve heads precipitates more changes to help your motor increase it's potential. Yes, a more aggressive cam is in the equation, but as TI said, you need to up your operating range to realize the benefits so you need to also go up with intake as well, say to the E-brock Performer RPM. You could go on E-Brock's web site and look at their packages that include "Preformance packages of Heads, Cams, Intakes, and Carbs". Look at the specs of each of these and go from there. You don't have to buy their products because you can get the same specs from other manufactuers. Balance out your components is the name of the game!!!

My 327 has a Comp Cams improved, dual pattern, regrind of the 300 horse Vette 327. I had a dual plane Bow Tie high rise intake and the same heads as you have with a worked Q-Jet. It worked great. I have since replaced the Q-Jet and Bow Tie with the E-Brock Pro Flow with the two barrel air valve and it is a little screamer (worth about 45 HP more over the carb) even though some of that comes from the intake which is virtually an E-Brock Air Gap modified for the fuel rails and injectors.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 09-22-2009, 04:26 AM
Registered User
 
Last photo:
Join Date: Sep 2009
Location: new zealand
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks Trees for your advice and comparison to your setup,will consider carefully my entire setup and what i want to get too,good advice from all.cheers
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last 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 for yourself.
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.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
327 350 horse camshaft chevyonly1221 Engine 2 07-23-2009 11:15 PM
327 small block price question ortamenxs Engine 9 03-15-2008 02:54 PM
Camshaft question. bodydroppedsquare Engine 20 02-06-2008 10:10 PM
amc 327 intake question stl3496 Engine 2 12-21-2007 05:58 PM
1965 Impala 327 Timing Question EazyDuzIt102 Engine 2 06-25-2004 03:07 AM


All times are GMT -6. The time now is 08:18 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.