[Old Goat Racer]

Originally Posted by njsteve

Yup. Thats the correct one but depending upon the year of manufacture it could be the later "one sender fits all" model.

I've had a few of these for 20+ years. How can one tell when they were made?

[njsteve]

Originally Posted by old goat racer

I've had a few of these for 20+ years. How can one tell when they were made?

I think the good early ones have the part number stamped above the threads versus the newer GM ones that don't have anything there.

[317th FMS]

If you google "1513321 GM" and click on that first PDF file there is alot of good info on this. I tried to add to the thread but it was too big a file.

[njsteve]

Yes. that one is:

http://www.lbfun.com/warehouse/tech_...eCF-Thread.pdf

It has some ohm spec charts for a variety of senders. It's a Corvette forum and they also talk about the problem with the newer GM senders. They also have some good photos of the senders as well.

By the way I just took the T/A out for a test drive with the mechanical gauge installed in the temp sender location. It's around 97 degrees outside at the moment and the car ran 190 most of the way with the A/C on full blast. It did heat up a bit (the car that is) once I stopped to assist the well-dressed, damsel in distress on the side of the road who was looking for a graduation party somewhere in the area and had no clue about what road it was on.

And of course on the return trip it seemed that everyone in the area who had a lawnmower, was out trimming their gravel as I tried to drive by.

[CaptCrunch]

Originally Posted by njsteve

Yes. that one is:

http://www.lbfun.com/warehouse/tech_...eCF-Thread.pdf

It has some ohm spec charts for a variety of senders. It's a Corvette forum and they also talk about the problem with the newer GM senders. They also have some good photos of the senders as well.

By the way I just took the T/A out for a test drive with the mechanical gauge installed in the temp sender location. It's around 97 degrees outside at the moment and the car ran 190 most of the way with the A/C on full blast. It did heat up a bit (the car that is) once I stopped to assist the well-dressed, damsel in distress on the side of the road who was looking for a graduation party somewhere in the area and had no clue about what road it was on.

And of course on the return trip it seemed that everyone in the area who had a lawnmower, was out trimming their gravel as I tried to drive by.

Are you running an original 4 row radiator?

[njsteve]

Originally Posted by CaptCrunch

Are you running an original 4 row radiator?

The 72's used a three-core. I'd love to put a four-core in it like I did with my Grandmother's 75 Firebird (original owner car). That car now won't break 165 degrees on a 100 degree day with the a/c going. But since the T/A has its original four-speed radiator (the one with no auto trans cooler fittings), I kept that one in the car after having it recored. The local radiator guy said due to the width limitations of the original tanks, there was no way to convert it to a four-core unit. Maybe after I get the car judged I may buy a four core and save the original but for now, I'll stick with what I got.

[CaptCrunch]

Originally Posted by njsteve

The 72's used a three-core. I'd love to put a four-core in it like I did with my Grandmother's 75 Firebird (original owner car). That car now won't break 165 degrees on a 100 degree day with the a/c going. But since the T/A has its original four-speed radiator (the one with no auto trans cooler fittings), I kept that one in the car after having it recored. The local radiator guy said due to the width limitations of the original tanks, there was no way to convert it to a four-core unit. Maybe after I get the car judged I may buy a four core and save the original but for now, I'll stick with what I got.

In my younger years I managed a large radiator shop. You could have a custom core made to fit your original tanks that would help some.........I copped out and put an Alumitech radiator in my formula......wouldn't look right for a car as original looking as yours but not bad for an after market aluminum radiator.....a three row is going to be marginal at best.......I didn't know they used 3 rows on 455's.........

[unruhjonny]

Originally Posted by njsteve

...
And of course on the return trip it seemed that everyone in the area who had a lawnmower, was out trimming their gravel as I tried to drive by.

ha-ha-ha!!

unfortunately I know exctly what you mean..

Originally Posted by njsteve

OK, just got the original, vintage 1513321 temp sender from 70RAIII, here is the updated chart:
...
Looks like the Wells sender is pretty darn close to the original GM sender's specs. I'd say it's a dead-on match given my pot of hot water on the stove, scientific method.

BAH-HA-HA!!

Originally Posted by njsteve

The 72 intake only has the one hole for the thermostatic vacuum valve drilled out and tapped. The other boss is not tapped. ....

crap!!

Here I was going to actually try to help & contribute to the thread, and you seemed to have stopped joking (or doing kitchen experiments) long enough to have beaten me to it!!