mixed rocker arms?
#2
Senior Member
RACING JUNKIE
Join Date: Jan 2006
Location: La.
Posts: 2,890
Some people run 1.5 on the exh. and 1.6 on the int. or visa/versa if they have a small lift cam. If that is /was what was happening you should have 8 1.5's and 8 1.6's with your set, if you dan't have an equal number then it's time to get another set of rockers.
JMO
Zip.
JMO
Zip.
#3
Senior Member
RACING JUNKIE
Join Date: May 2003
Location: Coldwater, MI
Posts: 2,998
Re: mixed rocker arms?
Originally Posted by craigs55
I have a newbie type question for you experts out there. I have noticed some mixed ratio rocker arm sets out there (1.5-1.6) and was wondering what the purpose for this is? :?:
#4
Senior Member
MASTER BUILDER
Join Date: Sep 2005
Posts: 134
Some single carb motors will pick up some HP with more lift on the corner cylinders because of being farther from the carb.I have 1.65 in&ex on 1 2 7&8 and 1.6 in&ex 3 4 5&6 single 4 sbc.Back to back test chaging from all 1.6 pick up just .02 Bill.
#5
Junior Member
SHOW GUEST
Join Date: Dec 2009
Posts: 4
valve lift
The whole idea is to get the valve open.
The higher ratio rocker accelerates the valve opening.
Unless you already have an excessive amount of cam event, you should gain power by increasing the intake rocker ratio.
In other words...If you do not gain power, you may already have more camshaft than you're using. Or the springs are insufficient.
The higher ratio rocker accelerates the valve opening.
Unless you already have an excessive amount of cam event, you should gain power by increasing the intake rocker ratio.
In other words...If you do not gain power, you may already have more camshaft than you're using. Or the springs are insufficient.
#6
Senior Member
RACING JUNKIE
Join Date: Jan 2012
Posts: 628
According to what I've been told by some of the engine guys at Childress, on the new Gen IV SBC (NASCAR), they use a very low profile cam, flat tappet lifters and 1.9 rockers, combined with about 185# of seat pressure . . They won't say what the actual seat pressure is, nor the cam they run (Manhattan Project) but they're getting 9200+ rpm out of them for 500+ miles, WFO . .
Something to experiment with, perhaps?
Something to experiment with, perhaps?