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Super_Dave · 02-13-2017, 05:43 PM

Well... I was able to solve part of the Voltage gauge fluttering between 15.5 and 18 and the Stereo and Climate Control working intermittently.

The new Alternator from SUMMIT was bad. That's the third new part from SUMMIT that was a piece of crap. $141 later, a new NAPA alternator is in and I am pulling 14.5 steadily.

The intermittent stereo and cc was traced to a bad (new SUMMIT part) ignition switch module on the column... which was replaced in the wiring harness install a few weeks ago. We adjusted the ignition switch enough for the stereo and cc to work but starting the engine became nearly impossible. Backing off the adjustment made starting easier, but we lose the stereo and cc fan... so, a new NAPA ignition switch is on order.

Lastly, after installing the new, warmed over 700r4 OD transmission, and hoping to go from 12 mpg to the mid-high teens, has proved disastrous. I was getting 12 mpg with the TH350... and my last tank with the 700r4 netted me a whopping 7.91 mpg! Well worth the $2,500 investment, right ?!

We have checked everything fuel related... no leaks anywhere, timing is 12°, idle 750rpm, 3:73 rear gears should be optimal with the .67 OD final ratio... should have me in about 2.50 at cruising speed...

So, I am at a complete loss as to where the mileage is going. Speedometer and tach are spot on, so I know my numbers are accurate. At this rate, it would take me about 5 tanks of gas, or $200+ to go from Portland to the California border. Hardly worth the effort to take it out to even go to the post office.

02-13-2017, 05:43 PM	#161
Super_Dave Registered User Join Date: Jul 2014 Location: Sherwood, Oregon Posts: 974	Re: 1974 C20 Soon to become a project... Well... I was able to solve part of the Voltage gauge fluttering between 15.5 and 18 and the Stereo and Climate Control working intermittently. The new Alternator from SUMMIT was bad. That's the third new part from SUMMIT that was a piece of crap. $141 later, a new NAPA alternator is in and I am pulling 14.5 steadily. The intermittent stereo and cc was traced to a bad (new SUMMIT part) ignition switch module on the column... which was replaced in the wiring harness install a few weeks ago. We adjusted the ignition switch enough for the stereo and cc to work but starting the engine became nearly impossible. Backing off the adjustment made starting easier, but we lose the stereo and cc fan... so, a new NAPA ignition switch is on order. Lastly, after installing the new, warmed over 700r4 OD transmission, and hoping to go from 12 mpg to the mid-high teens, has proved disastrous. I was getting 12 mpg with the TH350... and my last tank with the 700r4 netted me a whopping 7.91 mpg! Well worth the $2,500 investment, right ?! We have checked everything fuel related... no leaks anywhere, timing is 12°, idle 750rpm, 3:73 rear gears should be optimal with the .67 OD final ratio... should have me in about 2.50 at cruising speed... So, I am at a complete loss as to where the mileage is going. Speedometer and tach are spot on, so I know my numbers are accurate. At this rate, it would take me about 5 tanks of gas, or $200+ to go from Portland to the California border. Hardly worth the effort to take it out to even go to the post office. __________________ --Project BABA YAGA!... http://67-72chevytrucks.com/vboard/s...d.php?t=655783 --Project BABA YAGA!... http://67-72chevytrucks.com/vboard/s...ghlight=Belair "Life is tough - wear a cup!" "Old Enough to Know Better - Too Young to Resist" "Junk is something you will need three weeks after you throw it away."