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If you listen to some of these people on this blog I will show you where they are incorrect with their logic.
Will remark my comments in red as to the errors in their belief issues.

First, ... you have a "street use" vehicle, … not a race truck or a vehicle that will rarely see over 80 mph nor an engine that will ever be over 5 grand operation. Great ideas if this is a "race truck", but a waste of money time and drivability for an everyday cruiser.

Now to point out the "perceptual errors" for a street operated vehicles.

In post #34 it was stated:

"on the throttle body spacers the let each cylinder take roughly 2 to 10 or more cubic inches of extra air in at the intakee of each piston stroke... just like a wiend tunnel ram intake does on a drag car so to enlarges the overall space theCFM. i would geuss it increases as the flap or buttlerfly rises or moves away from the upper intake plemium".

Well this person has no concept of physics as how gaseous materials act against solid materials, nor did he post air flow data from an independent test lab to support this claimed statement. Every motor is a "glorified air pump". Installing any object in a air flow route will not improve any air flow increase to the most restrictive engine operation component. Any improvements will occur when the most restrictive air flow route is improved.

In post #36 it was stated:
No. Throttle body spacers increase the volume of the plenum (the space between the throttle blade and the intake valves). What this does is allow a greater volume of air to be stored behind the blade, which can slightly improve throttle response. ( Great if the motor is operated at a much consistent higher rpm's, not viable at street use level rpm's. Would love him to explain intake to cylinder head air velocity requirements at lower rpm operation??? Even cylinder head flow to intake runner length ratio's to maintain air velocity requirement for throttle response lag??? Or why some engine induction systems use IMrocs for performance gains like in the Z series motors??? ) It does not result in more air going into the cylinder, nor does it result in an increase of flow CFM through the intake.
A tunnel ram intake on a drag car serves a completely different purpose. Tunnel ram intakes are to have a tall intake runner which is essentially a straight shot from the throttle plate to the cylinder. This improves flow in the higher RPM range that drag cars are built to run in, and reduces potential low-end output of the engine.

Now my favorite post!!!
In post #39 the following items were stated:

Twin 11" Fan's on the 02 (If he's smart, they should be the 2750 cfm SPAL fan module???). 180* thermostat.
(That is his first mistake!!! ALL computer controlled motors need 195 degree thermostats to raise the cylinder heat temp up so the fuel entering the combustion chamber is much closer to fuel vaporization rates when ignition occurs. This 180 degree stat use is a pre computer, race configuration mindset from the 1960's and not conducive to modern computer controlled cylinder head designs).

GET RID OF THE DEXCOOL . This is the worst stuff that GM ever put in the 4.3L. Put FLUSH the DEXCOOL OUT, and put in 2 cans of prestone Cooling system cleaner. Run it for a week this way (preferably in the spring or Fall before 1st freeze). Doing that procedure greatly raises the risk of heater core, cylinder head / and or intake manifold gasket failures. Sometimes it eats away the water pump shaft seal. Having this much cleaner in for so long will eat away the protective elements that have been built up on older high mileage vehicles. Since he claims he is an expert on Dexcool being the "Worst stuff" and "Green stuff" anti freeze and which is better, I will leave some "PROFESSIONAL OPINIONS" reference cites so we can clear the crap on this issue!!!

Flush out the crap using a Prestone Flush and fill kit. Fill with 50/50 Green stuff and add a can of Water Wetter for stock 4.3L systems. Change the Thermostat to a 180* unit (see above statement in red!!! ).

I'm not totally sure now (That should tell you he does know about chemistry, physics or electrical theory at any level. What he is describing is "GALVANIC COROSION and does not have the slightest clue as to "WHY" or understand the "Root Cause" for why this is happening. His use of cleaning detergents and type of parts used is highly questionable to the problems he is describing) but the radiator I got for a Gen 4 Vette (87 or thereabouts). Then add ground straps to the Radiator and the core support to ground the radiator. Because the Radiator is not grounded electrolysis occurs with the Dexcool and literally eats your radiator from the inside out. Funny thing is I have the same orange Dexcool anti freeze mixture in my 2001 Sonoma for the last 18 years (my 1996 Grand AM had it for 20 years, no issues there either), along with the same anti freeze mixture (9 years) in my 2010 HHR with zero seepage or cooling system problems (don't have water pump ' thermostat failures either).

Secret is "how" proper flushing should be done (no mention of flushing the engine block where the corrosive chemicals settle after a systems flush) and using the right anti freeze chemistry along with the proper parts should be used to avoid zero cooling system problems.
Electrolysis (acidic / high iron coolant is present) on the nature of 2 to 4 volts DC. Get your Volt meter out and stick the + probe in the antifreeze and the - probe on a good ground. Flush, fill with 50/50 and check again without ground straps and with ground strap. The readings will be in mv range with ground straps. Glad he mentioned that fact that 99.999% of mechanics and techs don't know the physics of this issue.

He is using "high carbon" rubber radiator hoses that transmit voltage along with "high iron and or high acidic water content" which he should not be use at all. Loose particles of iron in the coolant from motor wear generates the negative side of battery electron flow. The worn motor coolant aids as a internal ground strap of the electron flow in the vehicle. Having poor external grounds could eat up a radiator core if proper conditions exist.

Notice where there is no mention the use of "Distilled Water" as part of the anti freeze mixture??? If chemistry was understood, then the voltage reading in the coolant would be understood and near non existent.

The throttle plate will get rid of the turbulence at the front of the throttle body and attendant throttle lag. Leave the IAT PLUGGED IN, but move it to the front of the filter box. Gee, for better accuracy, performance, wouldn't it be logical to move the ACT sensor closer to the throttle blade to give actual temperature entering the motor not 2 1/2 feet away??? I'd recommend leaving the Honeycomb in the MAF, and just clean it once a year. If any debris hits those two resistive elements, you'll get a Check engine light and the engine will go into limp home mode or die completely.

I get consistently 18-19 on short trip driving with the 02, and a high of 24 running empty. Towing I leave it in 4th and get 10-11mpg towing the trailer. I'll down shift on my own when I come to a hill and run up the hill in 3rd or 2nd gear. The trans also has the larger 1-2 and 2-3 servo's. Shifts like a THM400 not a C-6 ford slushbox. CHIRP's the tires on 1-2 upshift if I hit it hard.

I left the Jimmy stock except for the distributor and the 180 thermostat, as the wife drove it. She couldn't see out of the ZR-5 (funny as the ZR5 has 4 square windows and a "C" pillar that is smaller than the "C" pillar on the Jimmy. Go Figure.

The biggest thing with the 4.3L and fuel economy is keeping an eye on the engine vacuum. Run it between 14" and 16", and you'll maximize Fuel Economy. Use cruise control for this exercise Both run very nicely @ 70mph and 15". With a good tune, and with it cooled right, it'll do at least 20 on the highway all the time as long as your right foot isn't made of lead.
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