Just a few things to ponder on your rebuild. On the crank/bearing
issue, check your journals. If they are minimally worn, but still
unscored, etc. You may find that bearings .001 undersized will work. I
just did this to a 68 289 I freshened with rings and bearings.
Clearances came back to .002 for both mains and rods. For engines
that are at the wear limit and suffer low oil pressure, I have also
installed a high volume (not high pressure) oil pump to increase the
flow, and hence the pressure as a stop gap measure.
For a cam where you want a 'little more' with good street manners, I
basically look for a cam with a power band from 1500 to 5000 rpm. Used
to call them RV cams. They enhance low end torque. I am trying a Summit
brand cam in the above 289 (Edelbrock dual plane high rise manifold,
Holley 01850, all else stock). $90 with lifters and lube. I am not
advocating that particular cam, as it is cheap and I have not tried it
yet, but I had an Edelbrock Performer (mine was an RPM version) in a
Dodge 360 years ago. Got better intown mileage than the original
highway mileage, and I noticed the increase in power. Most of the
name brand cam manufacturers have software and/or tech lines. Call them
all and pick their brains. With respect to lift, duration, lobe centers
and split pattern or not, when they all say the same things, take heed.
Where they say different things, you will have to use your best
judgment. Generally with the overall poor exhaust port/runner shape of
SBF heads (they were designed that way to fit the engine bay, so I have
read), a split pattern cam is helpful. Biplane rather than a single
plane manifold enhances low end performance as well. Depending on how
you drive on the street, or if you track the car or not, will determine
how much power you need over 5,000prm. The higher the power band, the
poorer the low end performance, and subsequently the idle.
That's my opinion and observations. If some one who knows says
different, believe them, and tell me so I can learn too.... :^)
Pete in Maine, who never seems to get a chance to post much....
Anyone else here from Maine??
-----Original Message-----
From: classicmustang@yahoogroups.com
[mailto:classicmustang@yahoogroups.com] On Behalf Of Dan O'Reilly
Sent: Tuesday, June 02, 2009 8:51 AM
To: classicmustang@yahoogroups.com
Subject: [Classic Mustang] ...and speaking of camshafts...
Another decision to make in my engine rebuild: how to cam it. I'm not
looking to build a racer, but I am looking for more performance. I want
a reasonably good idle, as I'm not interested in shaking my wife's teeth
out while sitting at a light. I'm not really too up on camshaft
technology or what's really desireable, so this will be a learning
experience for me.
All input welcome...
---
Dan O'Reilly
1971 Bright Red Mach 1
2002 Black Deluxe Convertible
Colorado Springs, CO
------------------------------------
Yahoo! Groups Links
------------------------------------
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/classicmustang/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/classicmustang/join
(Yahoo! ID required)
<*> To change settings via email:
mailto:classicmustang-digest@yahoogroups.com
mailto:classicmustang-fullfeatured@yahoogroups.com
<*> To unsubscribe from this group, send an email to:
classicmustang-unsubscribe@yahoogroups.com
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
No comments:
Post a Comment