1966 C1434 SWB Custom Cab

[CustomCab66]

So I'm trying to sort out a fuel gauge issue. The gauge reads a half tank when it's full. So I removed the sender and checked it with my meter. With the float down it measures .05 ohms and when it is up it measures 31.8 ohms (call it 32) . With the key on if you remove the brown wire from the sender the gauge shows over full but when you touch the brown wire to ground it goes to empty. Sounds like everything is up to par. I am leaning towards a bad gauge so now I'm waiting on the NOS gauge that I bought. I will compare the two once the NOS one shows up and post the readings I get off of both gauges.

I heard that GM changed the sender from 30 ohms to 90 ohms around 1965 or 1966. There is a chance that the sender is hooked to a gauge that requires a 90 ohm sender which is most likely unavailable now. Time will tell

[bj383ss]

Look forward to hearing how your gauge works out.

[CustomCab66]

My new fuel gauge came in so here's the comparison:

On the old gauge:
Post to post it measured 41.8 ohms, and the current limiting resistor measured 24.8 ohms respectfully.

On the new gauge:
Post to post it measured 38.5 ohms, and the current limiting resistor measured 21.0 ohms respectfully.

Before removing the old gauge from the truck it displayed a fuel level just below 1/2 a tank (1/16-1/8" to the left of the 1/2 mark) are u tracking.

After I installed the new gauge it was right on 1/2 a tank. The problem i was having before changing the gauge was the always reading too low. Only time will tell once I run to town and top it off. For now it appears as if the new gauge just might be more accurate (I hope its right on).

[CustomCab66]

Gas gauge works perfect. I also replaced the antenna with one I found on eBay. The antenna looks just like factory. I replaced the heater duct hose under the dash so the defrost blows out of both holes now.

[northern 85]

Any updates?

[CustomCab66]

No changes recently how ever I'm considering on installing a big block to replace the 400sbc. The 400 is starting to smoke on startup for a second or two. The 400 is already bored .040 over and another rebuild might cause extensive overheating issues during heavy traffic. My only concern is there a long tube header made for a big block in this era of truck?

[CustomCab66]

I would go with a 283 or a 327 but I do not have one available. On the other hand this 454 that I picked up for 400.00 is nearly a complete long block and it is stock bore. The cylinders still have the cross hatches from the original hone job. It probably only has 30-40k miles on it. It is a CWB engine code which is either a 73 Chevelle SS or Monte Carlo SS. I know it's only a two bolt main but 400! I've seen the short blocks go for between 500-700.

[Captainfab]

The '73-'87 headers is what I used in my '66 Suburban. Regardless of which header you use, the top flange of the frame will need trimmed slightly for clearance. If you need more ground clearance, Chevelle headers will work, but not with the bellhousing crossmember in place.