400 SBC, do i need bigger camshaft ? - 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 05-26-2013, 08:26 PM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
400 SBC, do i need bigger camshaft ?

Engine is 1975 model, the block # is 817 and it's 2 bolt block with main studs Heads are # 882 that have been pocket ported and do have 1.94"/1.5" valves. It's been bored 0.030" over and has piston's that gives 8.75:1 compression Crankshaft and rods are stock.
This engine is going into a 1971 Vega # 2700 lbs curb weight, Th-350 trans, 3000 stall TCI streetfighter converter. 12 bolt with 4.10 gears and posi. and the tires are 275/60x15. Current cam is Crane 260 - H-260-2 Hydraulic Flat Tappet Camshaft for Chevrolet 1957-1987 V-8, 262-400 intake is 2101 Edelbrock Performer, 750 cfm Holley 4150 sitting on top of a 1" spacer. headers are 1.3/4" long tube's with dual 3" exhaust.
This is mostly a street car, but i would like to race some 1/4 mile drag racing once in a while. 75% street / 25% strip

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-26-2013, 09:25 PM
vinniekq2's Avatar
Registered User
 
Join Date: Jun 2012
Location: BC,Canada
Age: 56
Posts: 8,654
Wiki Edits: 0

Thanks: 365
Thanked 858 Times in 820 Posts
not a great cam but I guess ok
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-26-2013, 09:45 PM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 13,313
Wiki Edits: 326

Thanks: 838
Thanked 1,152 Times in 951 Posts
Quote:
Originally Posted by GTVega View Post
Engine is 1975 model, the block # is 817 and it's 2 bolt block with main studs Heads are # 882 that have been pocket ported and do have 1.94"/1.5" valves. It's been bored 0.030" over and has piston's that gives 8.75:1 compression Crankshaft and rods are stock.
This engine is going into a 1971 Vega # 2700 lbs curb weight, Th-350 trans, 3000 stall TCI streetfighter converter. 12 bolt with 4.10 gears and posi. and the tires are 275/60x15. Current cam is Crane 260 - H-260-2 Hydraulic Flat Tappet Camshaft for Chevrolet 1957-1987 V-8, 262-400 intake is 2101 Edelbrock Performer, 750 cfm Holley 4150 sitting on top of a 1" spacer. headers are 1.3/4" long tube's with dual 3" exhaust.
This is mostly a street car, but i would like to race some 1/4 mile drag racing once in a while. 75% street / 25% strip
That cam is perfect for the static compression ratio of the motor. If you want to run more cam, raise the static compression ratio. Be aware though, there is only so much to be had with those heads. More cam would need more heads also. The camshaft is not a single item that stands alone in the motor, it has to be custom tailored with the other characteristics of the motor. Although not all members of this board like this chart, it will give you some idea of the static compression ratio that you will need with what cam timing.
http://www.crankshaftcoalition.com/w..._compatibility

Also, be aware that present day drag racing is actually bracket racing, so that anyone can run alongside anyone else. Theortically, a VW Beetle could race a Fuel Funny side by side, if the Funny didn't do a meltdown waiting for the light. Both cars will have a dial-in on the window and cannot go quicker than their dial or they lose. It's not like it used to be, where the fastest car went home with all the winnings. Now, you have to dial in respectably and cut a good light on the tree.

Last edited by techinspector1; 05-26-2013 at 09:53 PM.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 05-27-2013, 02:25 AM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Those cams are bigger than i had in mind. How high is a safe redline on a 400 SBC ?
I was thinking about a camshaft that has redline of about 5500-5800. But i guess you guys are more experienced than me when it comes to hot rodding.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-27-2013, 07:02 AM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Yes they are dished pistons, but smaller than stock.
Is it ok to rev a short rod 400 sbc to 6000-6500 rpm without a catastropic failiure ?
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 05-27-2013, 07:32 AM
vinniekq2's Avatar
Registered User
 
Join Date: Jun 2012
Location: BC,Canada
Age: 56
Posts: 8,654
Wiki Edits: 0

Thanks: 365
Thanked 858 Times in 820 Posts
Is your engine balanced and well put together?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 05-27-2013, 01:25 PM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The engine has not been balanced, Stock crank and rods and 0.030" over pistons. All clearance is good and the mains do have studs.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 05-27-2013, 01:30 PM
How fast is fast enough?
 
Last photo:
Join Date: Jun 2005
Location: St. Louis, MO
Age: 29
Posts: 9,477
Wiki Edits: 0

Thanks: 20
Thanked 386 Times in 362 Posts
With that light car and gears and stall it'll be quick without much power. If I was to put a cam in that engine I'd like the 274h06 with 1.6 rockers. It's very easy on valve train and works great in low compression engines. It's cheap too. You won't see huge gains over what you have though, maybe 20hp as those heads are really choking it down.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 05-28-2013, 01:48 PM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
How much power should the engine be in the form it's now ? Hp and torque ?
Should peak torque be over 3000 rpm ?
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 05-29-2013, 09:00 PM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
300 hp +/- ?
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 05-29-2013, 11:24 PM
Registered User
 
Join Date: Aug 2012
Posts: 50
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by GTVega View Post
Engine is 1975 model, the block # is 817 and it's 2 bolt block with main studs Heads are # 882 that have been pocket ported and do have 1.94"/1.5" valves. It's been bored 0.030" over and has piston's that gives 8.75:1 compression Crankshaft and rods are stock.
This engine is going into a 1971 Vega # 2700 lbs curb weight, Th-350 trans, 3000 stall TCI streetfighter converter. 12 bolt with 4.10 gears and posi. and the tires are 275/60x15. Current cam is Crane 260 - H-260-2 Hydraulic Flat Tappet Camshaft for Chevrolet 1957-1987 V-8, 262-400 intake is 2101 Edelbrock Performer, 750 cfm Holley 4150 sitting on top of a 1" spacer. headers are 1.3/4" long tube's with dual 3" exhaust.
This is mostly a street car, but i would like to race some 1/4 mile drag racing once in a while. 75% street / 25% strip

You have a PM
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 06-02-2013, 08:32 PM
Registered User
 
Join Date: May 2013
Posts: 17
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
no one ?....
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:
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
Camshaft moves too much - SBC 400 Dino308gt4 Engine 13 03-12-2008 02:41 PM
Timing woes on SBC 350 with bigger cam. Brawler Engine 5 09-07-2007 05:33 PM
Help me design a 400 SBC around this camshaft shockers69 Engine 9 02-12-2005 09:27 AM
Bigger exh manifolds for SBC? FASTCHEVY Engine 18 05-08-2004 11:34 PM
bigger cam for sbc 66truck4spd Engine 11 04-28-2004 02:10 PM


All times are GMT -6. The time now is 09:20 PM.


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.