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Old 07-02-2020, 06:33 PM   #1
jcwren
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Water connections for Offy manifold heat plate?

I'm installing an Offy 5416 intake on my 250 this weekend, and have the hot water plate for it. Where should I plumb to for the source and return?

I have the temperature sender for the gauge in the 1/2" NPT port in the thermostat housing, and the sensor for the Sniper EFI 2300 in the 1/2" NPT port that's about 8" back from the front of the head.

Thanks!
--jc
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Old 07-03-2020, 08:19 AM   #2
old51sedan
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Re: Water connections for Offy manifold heat plate?

I have these on a 51chevy with a 235. Hard to see them, but I did mine with heat from the exhaust headers. You can see the copper tubing in the picture. I have a set for my 292 in my truck, but they are not drilled for the tubing. Thinking of drilling so that I can install them the same way. Gives instant heat this way with shorter pipes to install. I believe it looks better also.
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Old 07-07-2020, 01:10 AM   #3
vetnat
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Re: Water connections for Offy manifold heat plate?

So, forgive my ignorance, but instead of hot water running through the carb plate, its just hot air? I like this idea, especially the fast heating up part (I'm in Canada). If possible, could you post some pics when you get a chance? Thanks.
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Old 07-07-2020, 08:23 AM   #4
old51sedan
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Re: Water connections for Offy manifold heat plate?

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Originally Posted by vetnat View Post
So, forgive my ignorance, but instead of hot water running through the carb plate, its just hot air? I like this idea, especially the fast heating up part (I'm in Canada). If possible, could you post some pics when you get a chance? Thanks.
I have a feeling you were asking me about this setup. Not much to take a picture of, Theses are Fenton headers on my 51. They came with a threaded hole in each one of them just for this setup. You can see the rear one in the picture. I simply separated the intake from the exhaust manifold. Where they bolted together on the intake is a small 3-4" area that is indented which was where the original exhaust heated the carb to start with. I simply cut a square thin plate about 1/4" the same size. It seems like (this was 10 years ago) I drilled two holes in it, welded a nut on and screwed a brass fitting into them and each of the headers. Then just simply bend a short piece of tubing from each header to one of the fittings in the plate, it doesn't even matter which one as it just goes in one side and out the other, but keeps the carb warm enough so that it won't freeze up. To me it looks better than tubing running around the motor and you can polish the Cooper if you want to. It helps if you go from the front of the plate to the rear header as it's a short span and easier to bend the Cooper. Also you may want to put the fittings in the plate offset to avoid being in each others way. It's a tight space, but it works well.
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Old 07-07-2020, 08:27 PM   #5
vetnat
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Re: Water connections for Offy manifold heat plate?

Thanks old51, yes my question was directed at you, forgot to use the quote function. The headers I have for my 235 do have threaded bungs in them, have not installed yet. A 292 is in the future. I assume for the plate you made, the holes are drilled into an edge? How deep? Thanks again!
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Old 07-08-2020, 08:20 AM   #6
old51sedan
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Re: Water connections for Offy manifold heat plate?

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Originally Posted by vetnat View Post
Thanks old51, yes my question was directed at you, forgot to use the quote function. The headers I have for my 235 do have threaded bungs in them, have not installed yet. A 292 is in the future. I assume for the plate you made, the holes are drilled into an edge? How deep? Thanks again!
The plate will not be very big, I drilled the holes close to the edge as possible, then welded a bolt over the hole so it would be on the outside of plate.Not much area under the plate, but all is needed is enough for the hot air to circulate. It might take you a few tries to bend the tubing and get it from headers to the plate, it's a pretty tight space, but should work fine for you.
I done this car about 10-12 years ago, so hard to remember all those little things.
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Old 07-08-2020, 02:49 PM   #7
vetnat
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Re: Water connections for Offy manifold heat plate?

I think I'm getting the idea now. Thanks!
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