Not only can it ruin engine performance, it can ruin your engine. The
concept of timing is to try and get combustion to occur at the best moment
to allow your engine to create maximum power. As your RPMs increase your
timing needs to be advanced so that combustion can occur at precisely the
moment your piston gets up to the top. As RPM's increase it takes less time
for that to occur. We're only talking milliseconds here but a millisecond
is a long time. If you advance too much you will ignite your mixture before
your engine is ready to use it, consequently pinging or detonation occurs.
Higher octane fuel may alleviate that at part throttle but when you get to
WOT the premature ignition and combustion chamber temperatures can start
burning valves, making holes in pistons, etc.
Ron
00 SLT QC 4X2 5.9 46RE 3.92 LSD
For modifications see my DML Profile
-----Original Message-----
From: owner-dakota-truck@buffnet.net
[mailto:owner-dakota-truck@buffnet.net]On Behalf Of Stlaurent Mr Steven
Sent: Monday, October 16, 2000 7:38 AM
To: 'dakota-truck@buffnet.net'
Subject: RE: DML: RE: FW: New dyno results, 4.7L Leach custom PCM
Could to much advance ruin the engine performance??
-------------------------------------------
Steven St.Laurent
Test Engineer
Test Branch, GSD, MCTSSA
MARCORSYSCOM, USMC
760-725-2506 (DSN 365-2506)
Work:mailto:stlaurents@mctssa.usmc.mil
Home:mailto:saint1958@home.com
-----Original Message-----
From: WMBARRET@aol.com [mailto:WMBARRET@aol.com]
Sent: Saturday, October 14, 2000 5:54 PM
To: dakota-truck@buffnet.net
Subject: Re: DML: RE: FW: New dyno results, 4.7L Leach custom PCM
I agree Steve, I wish you could advance the timing at will!! would be nice!
Yea, Mike Leach will give you whatever advance you want, maybe I'll send
mine
back and ask for 5 more degrees???? (10 Total degrees) hmmm??? got me
considering it now...
Matt Y2K-HEMI
In a message dated 10/14/00 8:46:16 PM Eastern Daylight Time,
cyberlaw@earthlink.net writes:
<< Subj: Re: DML: RE: FW: New dyno results, 4.7L Leach custom PCM
Date: 10/14/00 8:46:16 PM Eastern Daylight Time
From: cyberlaw@earthlink.net (Steven T. Ekstrand)
Sender: owner-dakota-truck@BUFFNET.NET
Reply-to: dakota-truck@buffnet.net
To: dakota-truck@buffnet.net
I'm sure they are talking about Mike Leach Co.
Milling the heads is an inexpensive hop up. Only problem I see is the
availability of Head gaskets and head bolts. Are the 4.7's torque to yield
style bolts???
I wonder if you can tell by a cranking compression test whether your
particular 4.7 was low or high spectrum on static compression. I can run
the test, but I wouldn't know what the numbers meant.
I wonder if Leach would put a little more advance in his custom flash for a
customer. I also wonder what would happen if you had an MP PCM and then
added a Jet stage 2 to advance it even more! It's ridiculous how far you
have to go and how much you have to spend just to bump up the timing!!!
-STE
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