Anybody running a COMP Magnum 270H cam? - 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 07-06-2005, 09:54 PM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Anybody running a COMP Magnum 270H cam?

Just wondering because I'm about to buy it for my sbc 350 (bored .030 over so it'll be a 355).

How does it sound? How's the RPM range? How's the power?

I know it'll be different because of people's different intakes etc...

But I'll be using an Edelbrock Performer intake.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 07-07-2005, 02:05 AM
bracketeer's Avatar
489 Lemans
 

Last journal entry: Street Legal
Last photo:
Join Date: Dec 2004
Location: Courtenay, BC, CehNehDeh
Age: 55
Posts: 2,139
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
comp cams

Most hotrodders I have seen here sway more to the Comp XE cams. I have used the XE268H and was happy with it. But I buy strickly Crane Cams these days.
__________________
[URL]http://members.shaw.ca/g.body.building[/URL]
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 07-07-2005, 02:12 AM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Yeah, I was looking at that one also, but was told the 270H was better for power steering and power brakes. This is in a street car by the way.

The diff. between the 268H and the 270H is like 6 in the lift. The 268H is 218 and the 270H is 224....
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 07-07-2005, 07:50 AM
killerformula's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Carburetor
Last journal entry: Clean up
Last photo:
Join Date: Oct 2003
Location: Northeast
Age: 34
Posts: 3,485
Wiki Edits: 3

Thanks: 13
Thanked 27 Times in 18 Posts
Quote:
Originally Posted by Malibu73
The diff. between the 268H and the 270H is like 6 in the lift. The 268H is 218 and the 270H is 224....

Those are duration numbers you're comparing.

K
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 07-07-2005, 08:31 AM
Derkyb's Avatar
Member
 
Last photo:
Join Date: Jan 2005
Location: okc, ok
Age: 39
Posts: 229
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Between myself, dad, brother, uncle, and cousin we have run the 256 -268's comp XE cams in 283-355ci engines and all have seen the same results. They have very crisp throttle response and excellent low end torque with respectable top end, however they dont have that snappity snap sound at idle but when you step down on it they sure do make some noise. I decided to try something different in my 496 and went with a 292 magnum and it sounds like a pro stocker at idle havent tried it on the street yet though. If you want more sound at idle id say go with the magnum if you want a good all around street cam go wit the 270 XE IMO.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 07-07-2005, 11:37 AM
New Member
 
Join Date: Dec 2004
Location: Austin, Tx
Age: 27
Posts: 22
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I have the 292, in my 327 O_O its pretty wicked.. need high comp and good heads, and a good stal for it tho. but i like its powerband
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 07-07-2005, 11:44 AM
strikingthematch's Avatar
Pure American Muscle
 

Last journal entry: Still Going
Last photo:
Join Date: Mar 2004
Location: VA
Posts: 688
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
I have the 270 mag. in my 355.
Engine runs great.
It really picks up power above 2500 rpms but the idle is good.
It is noticable but not even close to dieing.
I idle at 900 rpms and have no trouble dirivng the car. All power opt. (steering, brakes) work just fine.

I will say though I only have a 1200 stall and would suggest a higher one along the lines of 2000 depending on your gearing. (mine is stock 2.73) It really likes to sit above that 2000 rpms mark to make power now this is with heads made for 1800 and above flow so each set up will be diffrent. The 270 is suppose to be the biggest cam you can put in with a stock conv.

I have headers/intake so all that was taken care of. How this cam would be on a bone stock engine I can't really say. But it does work very well for me.

Chris
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 07-07-2005, 12:53 PM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by killerformula
Those are duration numbers you're comparing.

K
D'oh, that's what I meant


Thanks for the input you guys; a little info about what the engine will have:

Comp Cam 270H Magnum
Edelbrock Performer Intake
HEI Ignition
Quadrojet Carb
Roller Rockers
Comp Roller timing chain
Hydraulic Lifters
Short-tube headers custom fit for 73 Malibu Sedan
2-Bolt Mains
HV Oil Pump
Bored .030 over
Stock torque converter
Rebuilt Turbo350 tranny innit (700R4 going in later)
2.5" Dual Magnaflow exhaust system.
Balanced Crankshaft



I think the gears are still stock, and we'll be using the stock TQ converter. That's one reason this cam caught my eye, you can still use your stock
converter with it.


Edit - Specs on Cam:

Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.47 0.47
Duration At 0.006 Tappet Lift 270 270

Valve Timing At 0.006
Open Close
Intake 29 61
Exhaust 69 21

These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 224 224
Lobe Lift 0.313 0.313
Lobe Separation 110

Last edited by Malibu73; 07-07-2005 at 01:00 PM.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 07-07-2005, 02:01 PM
GoneNova/406's Avatar
Member
 
Join Date: Aug 2003
Location: columbus,ohio
Age: 58
Posts: 1,163
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
if you're looking for perf. and sound use 1.6 rockers with the 270 mag.i have the 280 in a 406 and the 1.6 and it sounds and runs good in a very heavy vehichle.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 07-07-2005, 02:02 PM
Member
 
Last photo:
Join Date: Jan 2005
Location:
Posts: 3,707
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
What heads are you running? What pistons? What is the static compression ratio? This cam will need 9.5 - 10.1 compression to have any decent off idle power IMO. If you're running dished pistons and large chamber heads it'll be overcammed by far. The cam must match the compression ratio for good overall power. If you get it right a good pump gas street engine will pump 150-180psi of cranking compression. If too much cam the cranking compression will be low and so will low rpm power. Consider using steel shim headgaskets on your rebuild- jegs and summit sell them for dirt cheap.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 07-07-2005, 10:21 PM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by GoneNova/406
if you're looking for perf. and sound use 1.6 rockers with the 270 mag.i have the 280 in a 406 and the 1.6 and it sounds and runs good in a very heavy vehichle.
I'm pretty sure they're 1.6 rockers, i'm not certain though.


baddbob

I will try to find out that information
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 07-08-2005, 01:24 PM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Hey all, just found out the size of the valves. Their 2.02/1.94. We think the rockers are 1.6 also, but I'll know the size of the heads/rockers for sure tomorrow.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 07-11-2005, 02:53 PM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Those are the valve sizes, our machinist just got done boring our block .030 over and just received the pistons he ordered.

He's going to measure the combustion chamber CC's and tell me in a few days when he's done grinding the valves so I can figure out the CR.

It's gettin' done
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 07-12-2005, 11:06 AM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Are those weird valve sizes for sbc? 2.02/1.94?
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 07-12-2005, 06:01 PM
Malibu73's Avatar
'68 Chevelle Malibu Sedan
 
Last photo:
Join Date: Aug 2004
Location: Oregon
Age: 27
Posts: 353
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Actually the valves are probably 2.02/1.60. The new pistons are dished from Sterling, and the heads are GM.
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
BBC Comp cam EX274H, Impala5967 Engine 2 10-01-2003 08:53 AM
IGNITION and CAM TIMING sum87mustang Engine 3 07-11-2003 07:52 PM
Cam Help black66 Engine 3 05-12-2003 06:15 PM
cam selection chevyelc81 Engine 9 09-17-2002 06:41 AM


All times are GMT -6. The time now is 06:28 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.