Long Overdue Progress! Doors Finished 3/17/26

[BBShark]

Still chasing gremlins before closing up the dash. Lots of little stuff, today was a defective door switch and cutting a hole for the door contacts.

Where a lot's of stuff has to be worked out before dash install





Lot's of people are not fans of these connectors. But, properly installed and maintained, I think they are OK.

 

[BBShark]

Installed gauges, not good

Oil gauge reads 85 psi at idle.

Fuel gauge reads Full (there is 1 or 2 gallons in the tank)

Tach reads 1100RPM at idle, Holley software says 900

Temp reads 205 and Holly software says 180

Some of the numbers on the tach and speedo flicker.

 

[SuperBuickGuy]

you have a Dakota Digital dash? those numbers sound like a common problem with it. I will solve this in my round of updates (and I've talked to DD about this). But it's pretty annoying when your dash gauge says 240 and the Holley gauge says 198... and the senders are right next to each other....

 

[BBShark]

I have New Vintage gauges. I think they are similar to DD, a supposed plug and play system. Everything is wired through the Speedo and Tach. Fuel, temp, pressure and battery plug into the speedo & tach.

https://newvintageusallc.mybigcommerce.com/20659-05/
Fuel Gauge reading full at almost empty tank: I checked the DC resistance (car off) of the fuel @ 1.2 ohm which doesn't surprise me because there is minimal gas in the car. However it should be reading empty at 0 ohms and full at 90 ohms (not full at 1.2 ohms). Stock GM sender.

Temperature gauge reading 205 but Holley software says 180. With the cat at room temperature, the temperature sender is 1.3k ohms at 60 degrees F. Not sure but I think it is supposed to be 500-600ohms at room temperature.

Pressure sensor reads 85psi at idle: Pressure sensor reads 0 ohms (car off). Supposed to be 240-33ohms (range 0-100psi)

 

[BBShark]

Not much help from New Vintage so far except for a YT video selling their products. Impossible to actually talk to someone.

So, today I fixed the fuel gauge. I suspect the Temp sender is DOA. I tested it with resistors and the gauge seems to be working correctly. The Pressure reading at 85psi is starting to look legit. I'm going to get a test gauge for that.

85psi at idle? That's concerning.

 

[rtj]

85psi at idle? That's concerning.

Make sure the units are psig. psia or kpa would be confusing. A side by side with an analog gage might be helpful.

 

[BBShark]

I just picked up a test gauge. Probably get that done tomorrow.

Also try a new temp sender.

 

[SuperBuickGuy]

I just picked up a test gauge. Probably get that done tomorrow.

Also try a new temp sender.

A couple things. Fuel senders, I've gone through hell trying to find a sender that works with Dakota Digital (and it seems both of your problems are things that DD have trouble with). I'll dig up the instructions - IIRC the Ford senders work opposite the GM sender (don't quote me, let me find that paperwork).

Temp sensors. DD knows of the problem and depending on the day you would get this advice: 1) check your grounds/run a ground from the battery to the block. 2) the sender is bad, and they sent me several, and finally, 3) figure out the difference in a percentage and put a resistor in line.

it is very frustrating to have the Holley telling me that the temp is 200 and Dakota Digital tells me 240.... especially since the senders are adjacent to each other and exactly the same. It does help, though because I can simply swap which sender is informing which to verify the senders are fine.

 

[BBShark]

I put a mechanical gauge on the oil pressure and it was 68psi from a cold start @ idle (Holley SW says 900rpm). When the engine was warm that was reduced to 60psi. I took the oil fill cap off the cover with the engine running and it looks pretty dry in there. It's been a while since I put the top end of the engine together, maybe 4 years ago. I used some red lube (Comp Cams?) that was really sticky and thick. I sort of remember thinking how was oil going to wash it out.

Also, I primed the engine about a year ago and I saw very little oil coming out of the pushrods. I damn near burned up a 1/2 HP drill as I recall. I used Rottella 15w-40w in the engine. I suppose it's possible that the cam lube is dried to a point where the oil won't wash out the cam lube?

I am probably going to put a resistor in the Temp gauge line. Holley SW says 175* and NVU gauge says 190* (resistance is 105ohms at 190*). I'm thinking 10-15ohms

 

[BBShark]

BTW, this is a Lunati roller in a 502BBC.

Started it up with the cover off and took some movies. This is oil being pumped out of the pushrod. So, I don't know if it's enough but it is getting oil. I have a movie but not really sure how to post it here. This is a frame from the movie that shows it.

 

[BBShark]

Changed the oil and filter. New oil is 5w-30, 10w-40 before. Slight reduction in startup pressure (65 vs. 68psi) with a mechanical gauge. So, it's not a restriction in the filter.

The long block has about 5000 miles on it and the top end is new. The pump is Melling. The cam is a Lunati retro-roller and I followed those instructions on start-up.

 

[SuperBuickGuy]

the ones to be concerned about on a BBC is the rearmost rockers.
I don't know about the red lube - and I mean, I've seen bad things with a motor assembled but not run - but that was decades (like 30 years). I'd be careful about thinner oil - with solid roller cams, they recommend 30w or 40w straight oil. Honestly, I think you're okay - the one I know of could barely be turned with a wrench, he thought the rings had stuck so he pulled it back apart to a mess....
Yes, it takes forever and a coon's age to get oil up and through all the various passages. If you're getting oil from the end rockers, you should be fine.

 

[BBShark]

An unexpected thing happened today. I had a mechanical pressure gauge and the New Vintage sender in the same oil port. I was trying to measure the resistance value of the NV sender at different pressures and compare to the mechanical gauge pressure reading. On cold startup the NV gauge read 85psi and the mechanical gauge read 65psi. So, as the car warmed up the pressure dropped on both gauges but the NV gauge dropped to 70psi and the mechanical gauge dropped to 42psi. I'm thinking it flushed out the old oil? Not sure, but I can live with 42psi.

I also bought a Holley pressure sender same as I have for fuel pressure. It is super accurate so I'm investigating ways to use it to drive the gauge.

 

[BBShark]

The Holley sender confirmed the mechanical gauge (although I don't have cold start psi). When warmed up, the Holley software says 42psi (same as mechanical gauge. So, I'm thinking my cold start pressure is actually ~ 65psi and settles to 42psi. That seems like the upper end of "normal" but it's acceptable. Better too high than low. Now I need to figure out how to fool the gauge into showing it's 42psi when it's reading 70psi.

 

[rtj]

Maybe they expect the user to adjust the calibration. Is there a way to enter new coefficients or gain and offset screws (digital or analog updates).

if they were 14.7 psi apart I’d say one is absolute pressure and the other is gage pressure.

 

[BBShark]

if you look at the NV pressure gauge when it warmed up it settles at 70psi. At the same time the mechanical gauge and the Holley sensor are both reading 42psi. The resistance value of the sender is 240-33ohms (0psi-100psi). The good news is that it is linear. I have a 500ohm rheostat that I used to find the sender resistance at 70 and 42psi. It is 50ohms difference. Put a 50ohm resistor in the line so I hope that is the fix. I did the same thing with the temperature gauge.

Not sure why they can't get this right. These types of senders have been used for a century.

 

[BBShark]

I finally got the fuel and oil pressure gauges calibrated with inline resistors. 85psi at startup had me concerned to say the least. So now back to putting the dash back together before I bury the gauges behind it. Been trying to do this for months now! Now it's too cold in the garage to work. Maybe more in a couple of weeks.

Here is my oil pressure setup with Holley pressure sensor and old time mechanical sensor.

 

[rtj]

Mr. Heater 30,000 BTU Vent-Free Natural Gas Radiant Heater

I get by with one of these. Under $200 when on sale. No odor, way better than the propane torpedo heater I used in the past.

Great that you got those gages working.

 

[BBShark]

I do have a HF propane radiant heater and It will pretty quickly raise the temp 10 degrees. I'm a regular at the local propane refill store. they know what I need when I walk in the door. I hate cold and I have lived in Ohio most of my life.

 

[SuperBuickGuy]

I do have a HF propane radiant heater and It will pretty quickly raise the temp 10 degrees. I'm a regular at the local propane refill store. they know what I need when I walk in the door. I hate cold and I have lived in Ohio most of my life.

View attachment 56448

my shop came with a stove made out of a steel pile. with proper banking I can get 700* out of it. take a wheelbarrow of wood per day but it heats 2/3rds of my shop (so 40x60 with 20 foot ceilings) to 63 when it's 15 outdoors.... the guy I bought it from knew what he was doing.

 

[BBShark]

Now that it's running I'm thinking I should get a filter. Here is a mockup for an elbow.

 

[BBShark]

I was able to install both dash panels today. It took me so long because I had to finish wiring before covering it up.

Projects coming up:

• I'm going to cast a replacement for the airbag, 1990 was the early days of airbags an it looks like a pillow. Going to try something that looks more retro.
• Start working on the gauge/console
• Electrical connection for the doors with contacts instead of wired. Door latches and electric windows.
• 3D print a duct for the air filter
• Probably a ton of other stuff

 

[phantomjock]

Ohhh - Dash and wiring.
I can hardly wait to be there.
SBG - Hates Wiring!

Cheers - Jim

 

[SuperBuickGuy]

SBG - Hates Wiring!

Cheers - Jim

Full Truth there.

 

[bobs77vet]

I was able to install both dash panels today. It took me so long because I had to finish wiring before covering it up.

Projects coming up:

• I'm going to cast a replacement for the airbag, 1990 was the early days of airbags an it looks like a pillow. Going to try something that looks more retro.
• Start working on the gauge/console
• Electrical connection for the doors with contacts instead of wired. Door latches and electric windows.
• 3D print a duct for the air filter
• Probably a ton of other stuff

View attachment 56573

looks good, puts my C5 seats to shame

 

[BBShark]

One project done. Filter duct!

 

[SuperBuickGuy]

nice

 

[BBShark]

I'm thinking of doing something similar to what you did but the lower half of duct will seal against the hood (when closed).

 

[bobs77vet]

that looks great

 

[BBShark]

Thanks.

So one thing off my list:

Projects coming up:

• I'm going to cast a replacement for the airbag, 1990 was the early days of airbags an it looks like a pillow. Going to try something that looks more retro.
• Start working on the gauge/console
• Electrical connection for the doors with contacts instead of wired. Door latches and electric windows.
• 3D print a duct for the air filter
• Probably a ton of other stuff

I'm working on the airbag casting. Might get it cast this weekend