rockers for 406 sbc 1.5 1.6 or both - Chevy Nova Forum
Visit our sponsor, National Nostalgic Nova
 
Steve's Nova Site is an automotive enthusiast website dedicated to the 1962 - 1979 Chevrolet Nova, Chevy II and Acadian automobiles. We work together to preserve, restore, drive, show, race and provide fellowship for these classic cars. This is one of the best places to find information about parts, rebuilding, restoration and racing. This website is not affiliated with GM, General Motors or Chevrolet in any capacity.

Go Back   Chevy Nova Forum > Body, Chassis and Mechanical > Drivetrain & Performance


StevesNovaSite.com is the premier Chevrolet Nova Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools Display Modes
Old 21st-May-2007, 08:51 PM   #1
aero993

Title: Nova Newbie
iTrader: (0)
Status: Offline
Join Date: Apr 2007
Location: Clinton, Md.
Posts: 40
rockers for 406 sbc 1.5 1.6 or both

I was on the phone today with Crower. I asked what rockers they recommended? I was told to use 1.5 and 1.6 rockers. I'm just curious as to how many out there split the rockers on there sbc 400. Is there a preference or a least favorable brand of rocker?

TIA
  Reply With Quote
Sponsored Links
Advertisement
 
Old 21st-May-2007, 08:54 PM   #2
DriveWFO
 
DriveWFO's Avatar

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Feb 2004
Location: PA
Nova(s): 74 Nova...R.I.P
Posts: 13,190
Every engine combo is unique. You can experiment with 1.5 and 1.6 rockers on the intake & exhaust and see what your engine likes. You might only see a difference on the engine dyno though. Remember to check for adequate pushrod hole clearance in the heads before swapping on the 1.6 rockers.
__________________
Don't worship false idles
  Reply With Quote
Old 21st-May-2007, 09:43 PM   #3
Fast Eddie
 
Fast Eddie's Avatar

Title: Nova Guru
iTrader: (1)
Status: Offline
Join Date: Feb 2004
Location: Temecula, CA
Nova(s): 1966 Nova
Posts: 2,927
I use 1.6 on a Lunati roller with .550 lift, the final lift is .570.
__________________
Fast Eddie
1966 Nova
408 cu in SBC
Aqua
  Reply With Quote
Old 21st-May-2007, 10:00 PM   #4
novamike
 
novamike's Avatar

Title: Nova Guru
iTrader: (1)
Status: Offline
Join Date: Feb 2004
Location: marshall,tx.
Nova(s): 66 ht
Posts: 2,215
rockers

Make sure that you use a long enough rocker stud so that your rocker is located on the stud and not on the threads, and has enough length to get good thread engagement for your poly-locks.
Installing roller rockers can create there own problems if you don't check the details.
Mike
__________________
406.th400.9 inch,lots of Duct tape.
Superglue is my friend
Home of the famous "Bubba" burger

Last edited by novamike; 21st-May-2007 at 10:02 PM. Reason: sp
  Reply With Quote
Old 21st-May-2007, 11:22 PM   #5
agpd45

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Nov 2006
Location: StL/Rolla, MO
Posts: 610
Quote:
Originally Posted by Fast Eddie View Post
I use 1.6 on a Lunati roller with .550 lift, the final lift is .570.
I'm probably just doing the math wrong... but with a camshaft with .550 lift with a 1.5 rocker, I get 586 lift with a 1.6 rocker.

Math: .550 divided by 1.5 and then take the number and multiply it by the new 1.6 rocker???

I'm probably doing a newbie mistake.

Artie
  Reply With Quote
Old 22nd-May-2007, 12:00 AM   #6
Mike Goble
 
Mike Goble's Avatar

Title: Nova Guru
iTrader: (0)
Status: Online
Join Date: Feb 2004
Location: Fairfield, CA
Posts: 8,138
.550/1.5 = .3667
.3667 x 1.6 = .5867
__________________
Time flies like an arrow. Fruit flies like a banana.
  Reply With Quote
Old 22nd-May-2007, 08:10 AM   #7
rhorne12

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Mar 2007
Location: Charlotte, nc
Nova(s): 1962 Nova
Posts: 587
I like the 1.5 exhaust and the 1.6 intake. There is more to it than just the difference in lift. The entire lift curve is changed by the rocker ratio. Most intakes need the quick lift to get the valve open and the flow started, most exhaust (except turbo) do not need that.
If the cam is not already too big, the intake 1.6 usually helps. One the exhaust, esp. automatic, the 1.6 doesn't seem to help or may even hurt performance a little.
  Reply With Quote
Old 22nd-May-2007, 09:37 AM   #8
Paul Wright
 
Paul Wright's Avatar

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Oct 1999
Location: Psychic Hotline
Posts: 8,407
Quote:
Originally Posted by Mike Goble View Post
.550/1.5 = .3667
.3667 x 1.6 = .5867
Ah,yah got me. That's what I get for using the adding machine (accidentally set to "cut") by my desk instead of the calculator
__________________
Quote:
Originally Posted by Paul Wright
Building a small, high rpm engine
with the perfect bore, stroke and rod ratio is very impressive...
like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.

Cubic inches is like Indiana Jones with a cheap pistol.
.

Last edited by Paul Wright; 23rd-May-2007 at 10:50 AM.
  Reply With Quote
Old 22nd-May-2007, 10:01 AM   #9
SeventyNova

Title: Nova Senior Member
iTrader: (0)
Status: Offline
Join Date: Jan 2005
Location: Airdrie, AB
Posts: 267
You were probably thinking that it was a solid cam with lash of 0.016", this would make the lift at the valve (0.586 - 0.016 = 0.570") Right??
  Reply With Quote
Old 23rd-May-2007, 10:23 AM   #10
Pwrtrip75
 
Pwrtrip75's Avatar

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Nov 2006
Location: Janesville, WI
Posts: 2,126
get the right cam you want and dont screw the geometry of the valvetrain up trying to get more lift. I had nothing but problems with 1.6s.
Bent pushrods, broken studs....
__________________
72 Nova- LS 370 88mm turbo 4 link
99 Transam-LS 370 76mm turbo
71 Chevelle slow 350 building a LS 5.3
  Reply With Quote
Old 23rd-May-2007, 10:53 AM   #11
aero993

Title: Nova Newbie
iTrader: (0)
Status: Offline
Join Date: Apr 2007
Location: Clinton, Md.
Posts: 40
The cam is made by Crower, the tech guy at Crower recommended splitting the rockers.
  Reply With Quote
Old 23rd-May-2007, 05:16 PM   #12
DriveWFO
 
DriveWFO's Avatar

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Feb 2004
Location: PA
Nova(s): 74 Nova...R.I.P
Posts: 13,190
Quote:
Originally Posted by Pwrtrip75 View Post
get the right cam you want and dont screw the geometry of the valvetrain up trying to get more lift. I had nothing but problems with 1.6s.
Bent pushrods, broken studs....
If the geometry is correct, it won't "screw" anything up. A lot of guys try different rocker combos out. Changing the rocker ratio effects more than lift.
__________________
Don't worship false idles
  Reply With Quote
Old 23rd-May-2007, 05:21 PM   #13
69NovaSS

Title: Nova Guru
iTrader: (0)
Status: Offline
Join Date: Dec 2004
Location: Funkytown
Posts: 10,142
Quote:
Originally Posted by DriveWFO View Post
If the geometry is correct, it won't "screw" anything up. A lot of guys try different rocker combos out. Changing the rocker ratio effects more than lift.
Yes it effects duration slightly too....and I think it opens and closes the valves faster if you increase rocker arm ratio..
__________________
NPHNP
Do you recognize this vin:114279W458662

Last edited by 69NovaSS; 23rd-May-2007 at 05:33 PM.
  Reply With Quote
Sponsored Links
Advertisement
 
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Roller Rockers/1.6 Rockers/Roller tip rockers Repointer Best of Drivetrain & Performance 101 26th-February-2007 10:36 AM
350-400 SBC Flywheel ? novaracer1 Drivetrain & Performance 2 12th-June-2006 04:08 PM
dual quad sbc build up sYc_12B Drivetrain & Performance 9 16th-May-2006 10:19 AM
sbc cyl-heads? Nova Bob Drag Racing Forum 18 2nd-April-2006 01:52 AM
longshot...Id rockers? Gates72ss Drivetrain & Performance 3 27th-March-2006 12:53 PM


Site best viewed set to 1024 x 768.

All times are GMT -4. The time now is 04:29 PM.

Custom Designed for Steve's Nova Site by: vBSkinworks

 
Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Lt

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.