LD4B Intake question

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SMCARNUT

SMCARNUT

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Just finished installing a complete 340 in my Demon took a 318 out of the car.
I have an LD4B intake on the 340. There is not a port for a mechanical water temperature sending unit.
My question what is everyone doing to run a mechanical water temperature gauge on this intake? I cannot be the first one with this problem.
Let me know.

20240408_190037.jpg
 
I think that you should sell that intake to someone building a 318 and put the money towards a better intake for your 340.

They sell adapters for the sending units at the auto parts store or online.
 
youre leaving a lot on the table using that intake on a 340,as stated above.you could go to a machine shop and get a hole drilled and tapped right behind the bypass hose, or get an adapter of some type
 
Did you enlarge the ports on the LD4B?

Or if ported intake and heads isn’t a concern, no big deal.

LD4B’s sell for decent coin these days. Not as much as LD340’s though which would be a match for your 340.
 
Since I’ve been down this road…. Pictured below from Summit racing is “Joe’s Racing Products” that will fix the problem.

Get a new gasket. It does come with an O ring on the bottom side. I don’t know what the hole sizes are off hand. There are two different sizes. Perhaps a Summit tech guy will know. Probably even check for you since your purchasing one. He’s be more apt to check for sure that way. He can gather everything up to check and then drop in a box.


IMG_2290.jpeg
 
The 340 is basic X heads mildy ported, Ld4b has been port matched, Mopar 484 cam, Doug's headers, and 2.5" Pypes exhaust system. I bought a thermostat spacer from Summit Racing, but the mechanical sending unit hits the thermostat. Figured somebody has run into this before and came up with a fix. I forgot about this issue when the motor was out, or I would have addressed it then.
 
Why not change to electrical? Easier(imo) to run/hide elec wire then damned capillary tube. TS17 is elec sender and threads right in.
 
Dear rumblefish360
I looked on Summit site and did not see the one from your picture, did the one from Joes fit over the original thermostat or did the thermostat go on top of the spacer?
Here are pictures of the one I did purchase from Summit today.
rumblefish360 said:
Since I’ve been down this road…. Pictured below from Summit racing is “Joe’s Racing Products” that will fix the problem.

Get a new gasket. It does come with an O ring on the bottom side. I don’t know what the hole sizes are off hand. There are two different sizes. Perhaps a Summit tech guy will know. Probably even check for you since your purchasing one. He’s be more apt to check for sure that way. He can gather everything up to check and then drop in a box.
Click to expand...

20240412_184255.jpg


20240412_184437.jpg
 
4spdragtop said:
Why not change to electrical? Easier(imo) to run/hide elec wire then damned capillary tube. TS17 is elec sender and threads right in.
Click to expand...
I may just hook up the temperature electrical gauge on my cluster. My cluster does not have an oil pressure gauge it has a light only so I installed mechanical oil and water temp gauges when the car had a 318 engine in it.
 
CFD244 said:
Thermostat above the water neck spacer. They work great. :thumbsup:
Click to expand...
My mechanical sending unit hits the thermostat if I put the thermostat on top. I even tried the smaller stat on bottom falls through hole. Large thermostat on bottom the housing leaks (I used a gasket top and bottom). May try to trim large thermostat to fit inside Oring thermostat on bottom (use Oring this time) that may solve the problem?
 
Back in the seventies, I ran a Torker 340 intake. It had no provision for a mechanical temperature gauge. I just drilled and tapped a hole in the intake's water jacket, between the thermostat and the driver's side head - basically where the factory location was, and where Edelbrock puts the boss for a temp gauge on their present intakes (see below). Without the cast-in boss of the later intakes, the casting wasn't real thick there, but I put several washers under the adapter, JB welded the washers and the adapter into place, then ran a mechanical temp sender. I ran this setup for over 15 years without any problem or any leaks. I don't have a picture of the old setup; the pic below is my present setup, but it shows where I put the temp sender on that old Torker. Cost: near zero. Sometimes I think ya'll overthink this stuff.

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65 Cuda 340 said:
Back in the seventies, I ran a Torker 340 intake. It had no provision for a mechanical temperature gauge. I just drilled and tapped a hole in the intake's water jacket, between the thermostat and the driver's side head - basically where the factory location was, and where Edelbrock puts the boss for a temp gauge on their present intakes (see below). The casting isn't real thick there, but I put several washers under the adapter, JB welded the washers and the adapter into place, then ran a mechanical temp sender. I ran this setup for over 15 years without any problem or any leaks. I don't have a picture of the old setup; the pic below is my present setup, but it shows where I put the temp sender on that old Torker. Cost: near zero. Sometimes I think ya'll overthink this stuff.

View attachment 1716235828
Click to expand...

On SMCARNUT’s intake, that particular boss isn’t there. It’s s a good idea though. The sensor just has to go into the cylinder head to clear.
 
I added triple gauges between console and ac diffuser. Mech oil psi(poly tube), elec.coolant and voltmeter). I left oem gauges in dash, just unhooked.
SMCARNUT said:
I may just hook up the temperature electrical gauge on my cluster. My cluster does not have an oil pressure gauge it has a light only so I installed mechanical oil and water temp gauges when the car had a 318 engine in it.
Click to expand...
 
rumblefish360 said:
On SMCARNUT’s intake, that particular boss isn’t there. It’s s a good idea though. The sensor just has to go into the cylinder head to clear.
Click to expand...
Right, that's why I had to add several washers, to get the sender up high enough to clear the floor of the water passage.

I edited my post to clarify that my old intake did not have the boss.
 
65 Cuda 340 said:
Right, that's why I had to add several washers, to get the sender up high enough to clear the floor of the water passage.

I edited my post to clarify that my old intake did not have the boss.
Click to expand...

As seen…. I took a lazy way out… IF it was just for the temp sender. But I’ll be running water to it. The unit I have has 4 ports.

I got a check that thermostat question out in a second. I should know the answer since I played around with it some. But I can’t remember at the moment.
 
To answer the question….

First! Price the use of dual fittings on the side of the ext need housing. This is a must with this unit. IDK about others.

The below is a standard thermostat.
This is a Go!

IMG_2292.jpeg


IMG_2293.jpeg


IMG_2294.jpeg


The below is a “NO GO!” The high flow thermostat. The top doesn’t allow the temp gauges sensor end in. It will not fit.

IMG_2296.jpeg


image.jpg
 
SMCARNUT said:
My mechanical sending unit hits the thermostat if I put the thermostat on top. I even tried the smaller stat on bottom falls through hole. Large thermostat on bottom the housing leaks (I used a gasket top and bottom). May try to trim large thermostat to fit inside Oring thermostat on bottom (use Oring this time) that may solve the problem?
Click to expand...
Geez, not sure what to say. Mine worked perfect......I do use a Robert Shaw high Flow, but I'm not sure if that would matter. Can you use a Male/Female pipe fitting to get your sending unit "out" a little for clearance?

If the stat gets mounted below the sending unit, in the event of a stat failure, you'd never know the engine temp before it was too late.
 
Just incase…. The thermostat will not go into the top.

image.jpg
 
CFD244 said:
Geez, not sure what to say. Mine worked perfect......I do use a Robert Shaw high Flow, but I'm not sure if that would matter. Can you use a Male/Female pipe fitting to get your sending unit "out" a little for clearance?
Click to expand...

Perhaps I have the wrong stuff.
The fittings pictured above do what you suggest.

Can you get a picture of yours?
 
Now, I did find something interesting. On the older water pumps sold now, new/rebuilt (?) today. They come with an adapter. The gauge sensor will screw into the one adapter which screws into the second adapter and will screw into the by pass house outlet on the intake.

As pictured below, the trick is to get the black pipe threaded adapter with the inside of it ready to accept the adapter that the gauge sensor screws into. I don’t know if this is an easy to get item. Threads on the outside and inside.

You can see below on the older style water pump the black adapter in the water pump and then the hose end screwed into it.

Same deal on the intake plus on adapter fitting.

image.jpg
 
You could drill the hole in the back on the right side intake flange between the back 2 bolts going into the water port on the head.
 
I just drilled and tapped the intake manifold. This is a bad picture of it, but you can see it under the top radiator hose, dark blue fitting. LD340 intake

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I am curious, how did you get the intake ports on the LD4B to seal on the taller 340 ports? I have a couple LD4Bs and it seems there really isn't enough meat above the runner port to effect a good seal on a 340 Port. Have you run this engine yet???
 
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