strange cooling

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grumpy old man
Posts: 31
Joined: Fri Jun 22, 2018 4:08 pm

Re: strange cooling

Postby grumpy old man » Sun Aug 26, 2018 2:39 pm

About the forum, there was an e mail that I glanced at that seemed to be alluding to the fact that this is an a/c forum and not a power train forum. I will have to dig through the e mails and look at it more carefully to see if I misread it. Not a major issue I just don't want to ruffle someones feathers.

The DELCO 1530851 manifold that points the discharge line forward, what about the suction line. The crimp sleeve on the suction line out of the accumulator is right at the rear of the compressor which makes it necessary for the hose to go forward, loop and return. The current hose arrangement has both hoses discharging forward with the suction line making a loop about a foot forward of the compressor and then returning back to the accumulator. There is no other way to run it which is why I am asking about a manifold that will point both lines forward.

With regards to the engine/trans. if this were an occasional driver it would not be an issue but as my daily driver I do not want something that causes me irritation. It is worth the time and money to me to make the LS swap and have something that I know will be what I am after. As for time, I can go through the engine and trans at my leisure get everything ready to drop in and in 3-4 days max have the old engine out and the new one in and running. I will just need to make sure that everyone understands that I will not be available during those days. (mostly my wife)

The way I look at it is by the time I buy a set of heads and have them made unleaded compatible, a cam and lifters, manifold and carb and a trans which will need to be overhauled and then install all of it on an unknown possibility that it will give me a package that I can live with, I might as well just go the LS route with known results. Down time where the vehicle will be unuseable will probably be a wash, money wise the LS swap will probably cost me about double.

I have been meaning to ask what is the popper in your picture? What is it for? I am guessing that it is what you are grinding camshafts for.
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bohica2xo
Posts: 561
Joined: Wed May 11, 2016 4:12 pm
Location: Las Vegas, NV

Re: strange cooling

Postby bohica2xo » Sun Aug 26, 2018 4:31 pm

I do understand the daily driver issue - I was looking at a vintage ragtop as more of a weekend toy.

There are a lot of different GM manifold sets out there, and a lot of them interchange. A couple of them that come to mind are
GM 14081324 , 10135634, 14046042

You can do an image search for GM compressor hose sets or manifolds & go from there. Lots of choices.

The little side valve single in that pic is the baby of the line with a 2.75 bore 8 a 4.625 stroke. The ohv version goes all the way to 3.50 bore & 5.0 stroke. Yes I make the cams - and much of the rest of it too. Cranks are Truett & Osborn, Rods are Carrillo. Enough bottom end to run boost & nitromethane.
grumpy old man
Posts: 31
Joined: Fri Jun 22, 2018 4:08 pm

Re: strange cooling

Postby grumpy old man » Sun Aug 26, 2018 5:57 pm

But what are they for?

Back in the quarter midget days we used to do everything possible to squeeze a little more power out of a, I think it was a continental single cylinder. One of the questionable tricks was to support the camshaft lobe in a polished cradle and smack the top of the lobe with a big hammer to broaden out the lobe. then by using springs that had lost tension, a trial and error thing, you could use valve float to increase lift and duration.

Any part that could not be identified as authentic was not use able in the beginner class.
grumpy old man
Posts: 31
Joined: Fri Jun 22, 2018 4:08 pm

Re: strange cooling

Postby grumpy old man » Tue Aug 28, 2018 4:14 pm

I have a v7 compressor for a c5 corvette coming with a v belt clutch. Now I just have to build all new bracketts. I used to have a small structural steel shop so manipulating steel I understand.
grumpy old man
Posts: 31
Joined: Fri Jun 22, 2018 4:08 pm

Re: strange cooling

Postby grumpy old man » Mon Sep 17, 2018 3:46 pm

OK, I have been since last Wednesday afternoon installing the V7 compressor, had to fabricate all new brackets. As has been the norm for this A/C install everything was a problem but it is in nonetheless. Wonder if there is anyone out there that could use a compressor/alternator bracket and a Sanden compressor for a 389 Pontiac? Ah but I digress, it is on and running 41 degrees at the nozzle in the recirculating position with an ambient temperature of 80 degrees in the garage at idle (750rpm), bringing the engine rpm up only brings it down about a degree or two. Pressures at idle 275/20. I put the stock 98 ford orifice in, what are the chances that the white .072 orifice would bring the high side pressures down, or as it seems to be working just drive it and see how it does.
grumpy old man
Posts: 31
Joined: Fri Jun 22, 2018 4:08 pm

Re: strange cooling

Postby grumpy old man » Fri Oct 26, 2018 2:50 pm

Driving it the nozzle temp was still climbing appreciably as soon as you would slow down so I tried the .072 orifice and it seemed to work the same as the .057. I figured that as soon as I can find a wrecked Chev or GMC van I will be doing the LS engine and trans change and the weather is cooling off so I figured i would live with it for now. Had to break down the system for another reason so I contacted Air Parts and had them supply an expansion valve and a transition fitting to plug it into the Ford spring lock.

Got it all together and charged it, 73 degrees ambient in the garage, 24 ounces of refrigerant and the pressures were 200 +- high and 32-33 low with a 60 degree nozzle. adding more refrigerant ran the high side up into the 250 psi range, did not change the low side appreciably and the nozzle held steady at 60 degrees. Running the engine up drops the high side pressure with the increase in air flow but does not change the low side or the nozzle temp.

Ideas? or should I scrap the expansion valve and go back to the .057 orifice.
grumpy old man
Posts: 31
Joined: Fri Jun 22, 2018 4:08 pm

Re: strange cooling

Postby grumpy old man » Sat Oct 27, 2018 3:10 pm

OK guys, If you are old enough you will understand what I am about to say, if not keep breathing and you will make it. GETTING OLD SUCKS. I have been racking my brain since I charged it wondering what the he... is going on. finally dawned on me. The car has been down about a month while I was doing what I was doing along with some body work. Finally got everything done had the stack of AC stuff in a box on the shelf and decided that it was time to get the Indian on the road again. I love my Quadrasteer GMC but the top does not go down, and while the rear steer is novel it is not nearly as cool as the Pontiac. So I am bolting on the compressor and stringing the hoses got it all together evacuated and charged it and no cooling. Seems I forgot to take out the orifice!!! Of all the things I have lost I miss my mind the most.

Once I realized what I had done I pumped the system down, The California ARB approved refrigerant cans with the built in valve and a bucket of ice water works for capturing and reusing refrigerant. CALARB actually did something that works without realizing it. I removed the orifice reconnected the hose and recharged the system. Approximately 24 oz of refrigerant 80 degree ambient. The system is operating at 225 psi high 28 psi low and the nozzle is between 42 and 44 degrees. Idling not on recirculating which means it was sucking in engine heat through the cowl vent I could watch the temp go up and down a couple of degrees. Don't know if it was the compressor or the expansion valve working or a combination but it doesn't change a degree with engine rpm. I am very much looking forward to a hot day to see what happens. Maybe I finally managed to get what I was looking for all along.

Just an FYI for anyone that may wonder in the future. The particulars of the system are: the firewall unit interior and exterior are out of a 98 Crown Victoria. No particular reason other than it worked out as far as the placement of the firewall hole and the defroster duct and it fit under the dash without modifying anything other than the glove box liner. I did have to manufacture a custom fan duct to fit in the original location which took about a day with the front end sheet metal off for total access. The compressor is a V7 off of a C5 Corvette, the only reason for the compressor choice was the mounting which I felt would be the easiest to build brackets for. It does have a v belt clutch off of a C5 compressor which gives it about a 30% overdrive. The condenser is a 27" wide 16" high parallel tube off of the internet which is the biggest that I could find as far a surface area to work with the original size vertical flow radiator. Hoses were just measure and have made locally.

As soon as we have a hot day here I will make one last entry with a report on how it works in triple digit weather. hopefully that will be the final entry closing the thread.

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