Long Overdue Progress! Doors Finished 3/17/26

[BBShark]

When I was looking for it, Rustoleum sell s all kinds of specialty paints. They do make a rubberized undercoating.

When you painted over it, did it kind ok level off so that it looked like a dashboard texture? I saw a guy on YouTube do that with a cracked dash. filled the cracks, sprayed truck bed liner and then paint over the top. Looked pretty good on the video

 

[SuperBuickGuy]

When I was looking for it, Rustoleum sell s all kinds of specialty paints. They do make a rubberized undercoating.

When you painted over it, did it kind ok level off so that it looked like a dashboard texture? I saw a guy on YouTube do that with a cracked dash. filled the cracks, sprayed truck bed liner and then paint over the top. Looked pretty good on the video

look into flocking.... it gives an alcantara look to any solid surface (which is also amazing at hiding repairs)

 

[BBShark]

Got it wired up and shoehorned into place.

 

[BBShark]

Next Project: Door latching

I've converted my 1968 latches to 69-up. The difference is the top handles on a 69-up actually unlatch the door whereas a 68 does nothing and you have to push on the door lock cylinder to unlatch the door. Really weird setup, only lasted one year.

The complication is, you can't just swap out the door handles. Not even close.

So, I thought, why not convert it to electric and pop the door open with a switch? Setup a test with a 50lb spring scale using the existing door latching hardware (rods, levers, etc.). I couldn't get the door to unlatch with 50lbs of force!

Latch Pawl with push rod:



Modified Latch Lever Plate



I removed the handle from the plate and used the lever arms to transfer the pull from the spring scale to push the rod.

It does take a lot of force to unlatch the door (~20lbs) if you do it with your thumb. All the lever arms are 1:1 ratio. My assumption is the inefficiency in just about every part of this assembly is at fault. Primarily binding caused by offset loading. This is what causes Corvette latch handles to break. It's also what causes the push rod to bend on just about every C3 I've seen with the door panel off.

Bent Push Rod



My options:

My first instinct was to do this with a door popper solenoid. The problem with that is a solenoid doesn't have constant force through it's travel. That means you don't get full "pulling" force until the plunger is all the way into the solenoid. The latch force is actually highest when the plunger is out.

Then I started thinking I would use a linear actuator and transfer the force through a cable (like all modern cars) that is hooked directly to the latch. The only thing I am unsure of is this. I think I could do this in .25-.5 seconds. I think that is fast enough so that there doesn't appear to be any delay in opening but not really sure. Its probably something that will be pretty easy to mock up.

I think electric latching is done on lots of cars but I don't have a good feel for the timing.

 

[SuperBuickGuy]

if you use the tab the outside door lock is attached to, most solenoids will pull that.... worst part about that inside latch is there is so much play in it that even if you can pull hard enough, it may not be enough travel.

 

[bobs77vet]

When I was looking for it, Rustoleum sell s all kinds of specialty paints. They do make a rubberized undercoating.

When you painted over it, did it kind ok level off so that it looked like a dashboard texture? I saw a guy on YouTube do that with a cracked dash. filled the cracks, sprayed truck bed liner and then paint over the top. Looked pretty good on the video

it really had the same texture as before just a different color, i used the black and then top coated it with white.

it did make a nice texture finish but really its what you see now on your speaker box with a different color top coat. i could see it covering most defects underneath if they had at least a 400 level of smoothness to them. maybe even rougher if its not a straight panel in the sun and its a matte finish maybe even satin.

 

[vette427sbc]

......
Then I started thinking I would use a linear actuator and transfer the force through a cable (like all modern cars) that is hooked directly to the latch. The only thing I am unsure of is this. I think I could do this in .25-.5 seconds. I think that is fast enough so that there doesn't appear to be any delay in opening but not really sure. Its probably something that will be pretty easy to mock up.

I think electric latching is done on lots of cars but I don't have a good feel for the timing.

Keep in mind that if youre using the interior handle linkage to open the door, the actuator/ popper is going to have to move the interior handle as well, adding more force required to move the whole assembly. Also, without a spring to return a rack-style linear actuator, you will have to program them to return to the home position.

One more note as a car audio guy... assuming the bigger 10" speakers you installed are setup to play ~100hz and below, they will blow out/distort your smaller speakers being installed in the same airspace. If you have them all playing the same frequencies then this is less of a concern. Subs rely on a specific volume of air/pressure to control the cone. When the sub moves its going to move the cone of the smaller speaker with it.

 

[BBShark]

If you push the latch pawl (circled), aligned with the pivot, the force to unlatch is reduced to pretty manageable levels because you aren't twisting the latch pawl (which makes it bind). The other problem is the stock setup uses a push rod that transmits force to the latch pawl about an inch off center.

So I am going to make a lever that pushes the latch pawl that will not bind (force is not off center) and that lever will be pulled, not pushed. For the interior handle I want to operate that with a cable (pulling) and that cable would attach to the lever. The attachment would be slotted so that the actuator will not operate the handle. Also the handle will probably be switched to trigger the actuator so that the interior handle is an "emergency" method of opening the door if there is an electrical failure.

I am using a latching relay to extend/retract the actuator with a momentary switch input.



What might be a little weird about this setup is that there will be some delay between push the button on the door and unlatching. Right now I think I can do this in 1/4 second depending on relay latching speed etc. 1/4 second is pretty fast and I will mock it up first.

The speakers are chambered so that the subwoofers are isolated from the 6 1/2" speakers and only the subwoofers are powered by the amp. The 6 1/2 are powered by the stereo rear speakers. The volume needed was .2 cu.ft. (6 1/2") and .7 cu ft (10") for each (unported). It was a tight fit to get that much space and still fit the stowed convertible top in.

 

[BBShark]

Layed out a simple pull lever that corrects the binding issue. Should be pretty easy to test before making real parts:

 

[SuperBuickGuy]

you're building new door panels?

 

[BBShark]

Yes, I'm not sure if they will be modified stock door panels or custom. Maybe a little of both. First order of business will be to get the doors working. I can put the door panels off until after the car is drivable.

 

[phantomjock]

Does your latching mechanism allow for a manual back-up? Looks pretty cool.

Cheers - Jim

 

[SuperBuickGuy]

Yes, I'm not sure if they will be modified stock door panels or custom. Maybe a little of both. First order of business will be to get the doors working. I can put the door panels off until after the car is drivable.

cool. the reason I asked was there are channels the stock version uses to allow the door panel to be 'flat' but you've got this.....

 

[BBShark]

Does your latching mechanism allow for a manual back-up? Looks pretty cool.

Cheers - Jim

I will have a conventional "handle" on the inside of the car (that operates the latch mechanically). This would be a safety if I lost power.

However, the lost power issue is something I don't have a good solution for. Somewhere on the outside of the car I need access to power (in case I have to jump the battery). Which is inside the interior of the car to make things more complicated.

 

[vette427sbc]

Layed out a simple pull lever that corrects the binding issue. Should be pretty easy to test before making real parts:

That looks really cool! Keep us posted on the cable operation design. I have some cable operated door handles I was planning to use as well.
And good to hear about the individually sealed speaker enclosures... should sound really nice. The pics made it look like they shared airspace hence my concern :drink:
A battery tender type plug under the car could be a quick and easy solution for a total power loss situation.

 

[BBShark]

I'm hoping to get this tested in the next week. I'll post the results.

Thinking more about power loss. That is another advantage of using linear actuators. If the battery is discharged to 6-8 volts which seems unlikely, the linear actuator would still work, just slower. A solenoid probably wouldn't work in a low voltage situation.

A total loss of power (to both doors) seems really unlikely. However, I would like to rig up a way to get the hood open if I was "locked" out.

 

[bobs77vet]

Does your latching mechanism allow for a manual back-up? Looks pretty cool.

Cheers - Jim

I will have a conventional "handle" on the inside of the car (that operates the latch mechanically). This would be a safety if I lost power.

However, the lost power issue is something I don't have a good solution for. Somewhere on the outside of the car I need access to power (in case I have to jump the battery). Which is inside the interior of the car to make things more complicated.

I have seen jumping connectors on drag cars that are in the back valance and not very obtrusive, or even perhaps a battery tender quick disconnect somewhere hidden, just enough to power up the locks or slowly charge the battery

 

[BBShark]

Revised the layout to allow the cable pull handle to operate manually. The actuator (when switched) pushes the lever without being attached to the lever. So when you operate the handle from the inside of the car, the bracket pivots away from the actuator. This simplifies a couple of things and makes the system more adjustable (travel/force).

 

[mfain]

^^^^^^^^^

Well thought out!

 

[BBShark]

Progress Setback!

This is posted in the EFI section but thought I would post it here too. Looks like I'm making a major step back wards in this build.

So, here I am (more than) a year later. I didn't work on getting this tuned over the winter of 2020 because I didn't want to fill the garage with fumes. I did fire it back up in the summer of 2020 and the spark plug wire clips on the back cylinder melted (it was 3 inches above the header tube). Then the melted material dripped onto the header tube and resulted in a small (but persistent) FIRE. That fire was hot enough that it burned the insulation off the silicone wires. I was lucky, other than the wires there mas not any damage.

Next step was to replace the burned plug wires and separators. This took a while because I was so pissed that the clips caught of fire (I think they were MSD or Accell) and I had to remake the wires because they were custom length. I fired it back up later that summer and really made absolutely no progress on getting this tuned so I basically just gave up.

Until now. My current problem is that I was using an relatively antique EFI system (Holley Commander 950 purchased ~13 years ago) . It took me months to accept the conclusion that I would never get this to work after spending LOTS of time reading stuff on the internet and months of wiring this into my car. I suppose I'm now in the final stage of grief; denial, anger, bargaining, depression, acceptance.

Been shopping for a replacement and it looks like the best (easiest) replacement is a Holley HP EFI. I am dreading replacing this because I had integrated the wiring and ECU for the C950 into the car and disassembling the plenum to remove the wiring is a major pain. And, the HP EFI with all the stuff needed (dual synch dist., CD ignition) is pushing $3000.

This will definitely push everything back that is not related to getting the car running. But, if I can get it running, perhaps I will be motivated to finish the rest this coming winter.

Will I ever get this car on the road?

 

[rtj]

Ouch! Good luck!

Impressive work, just those gremlins.

“ an imaginary mischievous sprite regarded as responsible for an unexplained problem or fault, especially a mechanical or electronic one.”

 

[bobs77vet]

that sucks, but keep pushing through it and the pain will go away..... on my 37 ford I got so tired of doing body work I walked away for almost 2 yrs on the project. then i got intertested in it again. good luck

 

[SuperBuickGuy]

If it makes you feel better, I have a Holley Commander that's been sitting on my shelf for nearly that amount time as well.

I'll say this from the get go, I think Holley makes a great system, but I also think they have the worst tech/customer service of EFI company.

I was just talking to some people at Optima, FiTech is sponsoring them controlling a LS3 (I call it this for convenience). I'm using FiTech on my C3, and I plan on pulling the injectors from the housing along with the computer and wiring to run a port injection system... since they sponsor, maybe you can try them for free... you certainly bring an amazing build to them and have the racing chops that fit well within their marketing strategy....

I also like DIY tune and Megasquirt for much the same reason except I don't know of anyone they sponsor.

 

[BBShark]

If it makes you feel better, I have a Holley Commander that's been sitting on my shelf for nearly that amount time as well.

I'll say this from the get go, I think Holley makes a great system, but I also think they have the worst tech/customer service of EFI company.

I was just talking to some people at Optima, FiTech is sponsoring them controlling a LS3 (I call it this for convenience). I'm using FiTech on my C3, and I plan on pulling the injectors from the housing along with the computer and wiring to run a port injection system... since they sponsor, maybe you can try them for free... you certainly bring an amazing build to them and have the racing chops that fit well within their marketing strategy....

I also like DIY tune and Megasquirt for much the same reason except I don't know of anyone they sponsor.

I think there are a lot of people with C950 systems sitting somewhere. I should have given up on it 10 years ago when I:

• Found lots of mistakes in the installation manual (installation and wiring).
  
• Holley quit supporting it (2007) and told people to upgrade (buy) a replacement.
  
• Holley continued to sell these after 2007. No mention that you were on your own and it was a POS.

So it's going to be difficult to fork out $3000 for a "new" version knowing they could do the same thing again.

I'll take a look at the other offerings. One of my problems is that I built this motor with basically Ramjet 502 specs. That was basically all early 90's TPI sensors, ignition and throttlebody. Holley seems to be the only support for this because it is the same setup as their Stealth Ram.

 

[rtj]

I bought a 7531 msd programable ignition probably in the same time frame, 12 yrs ago. A year later the release a newer system and I was a bit po’d. But, it turns out they still sell 7531’s and a lot still use them, so I guess I lucked out.

Could you just pick up ramjet 502 components and save some $$? Either way, hope you get a good solution.

 

[BBShark]

I bought a 7531 msd programable ignition probably in the same time frame, 12 yrs ago. A year later the release a newer system and I was a bit po’d. But, it turns out they still sell 7531’s and a lot still use them, so I guess I lucked out.

Could you just pick up ramjet 502 components and save some $$? Either way, hope you get a good solution.

I hadn't thought of that. It looks like the newest version of the RJ502 uses a GM ECU made for marine use. I will have to check that out.

 

[rtj]

I bought a 7531 msd programable ignition probably in the same time frame, 12 yrs ago. A year later the release a newer system and I was a bit po’d. But, it turns out they still sell 7531’s and a lot still use them, so I guess I lucked out.

Could you just pick up ramjet 502 components and save some $$? Either way, hope you get a good solution.

I hadn't thought of that. It looks like the newest version of the RJ502 uses a GM ECU made for marine use. I will have to check that out.

Some one might have a hack/programmer for those old Chevy units.

 

[SuperBuickGuy]

If it makes you feel better, I have a Holley Commander that's been sitting on my shelf for nearly that amount time as well.

I'll say this from the get go, I think Holley makes a great system, but I also think they have the worst tech/customer service of EFI company.

I was just talking to some people at Optima, FiTech is sponsoring them controlling a LS3 (I call it this for convenience). I'm using FiTech on my C3, and I plan on pulling the injectors from the housing along with the computer and wiring to run a port injection system... since they sponsor, maybe you can try them for free... you certainly bring an amazing build to them and have the racing chops that fit well within their marketing strategy....

I also like DIY tune and Megasquirt for much the same reason except I don't know of anyone they sponsor.

I think there are a lot of people with C950 systems sitting somewhere. I should have given up on it 10 years ago when I:

• Found lots of mistakes in the installation manual (installation and wiring).
  
• Holley quit supporting it (2007) and told people to upgrade (buy) a replacement.
  
• Holley continued to sell these after 2007. No mention that you were on your own and it was a POS.

So it's going to be difficult to fork out $3000 for a "new" version knowing they could do the same thing again.

I'll take a look at the other offerings. One of my problems is that I built this motor with basically Ramjet 502 specs. That was basically all early 90's TPI sensors, ignition and throttlebody. Holley seems to be the only support for this because it is the same setup as their Stealth Ram.

Not being coy, but how much do you think it cost to drive from Seattle to California, register for Optima, and get hotels and food? I'm 100% behind what you're saying - because it does, at first blush, seem silly to spend the money twice. However, I could drive 6 hours and get parts when it failed (or have next-day-aired them). - but having the parts easily available is a thing because it will break, usually at the most inconvenient time.


*I'm still not throwing FiTech under the bus because I can't tell you what went wrong.

 

[BBShark]

Christmas in July

I finally pulled the trigger on all the stuff I need to replace the old C950 EFI "system". Holley HP EFI, Holley Dual Sync Dist., BBK Dual 58mm Throttle Body and Summit CD ignition.

I have been super busy with just about everything else but I would like to get this installed and running in the next month.

Wish me luck!

 

[rtj]

Christmas in July.