FJ60 V8 Conversion A/C ?
- Thread starter Elbert
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It sounds like he's waiting on conversion lines before he really dives into it, but it looks like the plan is to keep the GM compressor, use the Toyota equipment, but bypass the a/c amplifier and just use a relay. Does the system need a pressure switch? And I have no idea how the idle up works on the TBI350's. But I'd like to get that working so it doesn't bog the idle way down.
Why not use the amplifier. its there the switch feeds through it and the thermister safety feeds through it too. It is all Toyota except for the compressor. And that gets triggered the same as the Toyota compressor.
See that makes sense to me. Not sure why he'd circumvent that system?
- Thread starter
- #45
I'm no expert but what I did was (1) used a NEW GM compressor that matches my engine (in my case 5.7 vortec) (2) use the OEM condensor and other misc hard parts (3) used a factory GM A/C hose that mates to the compressor, then had the toyota ends put on the other end of the hose where it mates to the toyota parts. Used relay to control a/c compressor (toyota OEM wire triggers relay which then turns the a/c on /off, based on the a/c amplifier. I recall there being some mod or something done to the negative side of the coil (I know I've explained that before , but was not my idea...it does work) I don't recall the details off hand of what I did...as I type this msg, but Ive posted up notes on this before. I have A/C functional on my truck, and run mechanical radiator cooling fan. GM radiator fan (vortec 5.7) and matching GM fan clutch, 4 core OEM type radiator, custom radiator fan shroud. Others helped me and I learned a little here and there so I did not figure all of that out on the first round, so far I've been able to run R12. I would want to use the amplifier. I think there are some notes on using a modified amplifer as well, out on mud also.
That makes sense to me! Thanks for sharing. And it works fine without an a/c idle up?
Shop has hit it's first biggest obstacle with the A/C conversion. They can't find compressor adapters for the TBI350 compressor. Mosley has them for the LS style compressor (Denso 10S17F), but no dice for the 88-95 tbi.
**UPDATE**
We were able to find the adapters, in case anyone else runs into this issue. Vintage Air Compressor Adapter Blocks 34108-VUG
**UPDATE**
We were able to find the adapters, in case anyone else runs into this issue. Vintage Air Compressor Adapter Blocks 34108-VUG
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- Thread starter
- #48
yes it works fine without a/c idle up. I've not gotten around to looking to address that function.
Of course it would work better at idle with the idle up function working.... I have an electric pusher fan on the front of the condenser that I can turn on if needed. I think with the R134 its probably better to have more air flow across the condenser.
When I had my ECM re-programmed I asked for the idle speed to be bumped up from stock to about 800 rpm as I recall, but I don't think that was ever done and I was too busy trying to get it running to screw around with another 2-3 weeks down time. ON truck with manual trans....non issue to increase idle speed RPM within reason...might be a simple option if available. With the 5.7 vortec as I understand the high idle function, the ECM has to get a trigger signal to know that the A/C is on, and therefore to increase the idle speed. One day I'll look into that as my other projects need to get wrapped up some time this decade.
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- Thread starter
- #49
Don't know if new GM A/C hoses are available for 5.7 TBI setup but a real good solution in my view is to modify a GM OEM A/C hose. Leave it stock where it connects to the GM compressor, modify the other ends (take the GM fittings off and add the toyota fittings to the GM hose) works great. I had a hydraulic hose shop do mine.
- Thread starter
- #50
I see a Delco hose like I'm talking about on the rock auto site. Is this pic not the stock hose that mates to your compressor on TBI 5.7 ?
Just an idea as I mentioned above to modify. the GM hoses are nearly indestructible, there is more than one way to do this. I did not have much luck with the adapters as I initially tried those on my engine with some custom
hoses....was not satisfied with sealing issues.
Just an idea as I mentioned above to modify. the GM hoses are nearly indestructible, there is more than one way to do this. I did not have much luck with the adapters as I initially tried those on my engine with some custom
Thanks for the feedback! I'm less concerned with the idle up, and I do have an H55 manual behind it, so I'll look into bumping the idle up a smidge. He already ordered the adapters, so we'll see how they do. But I do think you're spot on, and using the GM lines would ultimately work better.
Are those the charging ports built into the hoses?
Yes. The GM hose assembly for that era has the high side and low side as part of it.
- Thread starter
- #54
as noted above, yes. I would have to say that unless you are doing some nice custom setup with the right hoses.....modifing a GM hose is my preferred choice. I did something similar on my 5.7 vortec, I'm using the stock GM OEM a/c compressor hose where it mates to the GM A/c compressor, then I modified the ends to use the toyta relevant fitting on the end to connect to the evap core and the condenser (best choice on a/c hose setup for engine swaps) in my view.
look around on rock auto, if its an AC delco A/C hose its nearly bullet-proof, in comparison to running an adapter at the A/C compressor, as I noted in my case, I was never satsified with the adapter at the compressor side (use what you have to use) but if there are choices consider whats out there to the extent you can. I never felt that in my case the adapter sealed well at the compressor side. setup is different on 5.7 vortec vs other models of 5.7 pending year model..etc.
Hey All, I have to jump in on this thread because I just returned from the AC shop and he said the PO (or his builder) wired the GM Compressor directly to the AC on/off button on the climate control. I have a 2004 L59 5.7 LS. The system is charged and operating, so not needing advice on hoses, etc. No electric fan needed. My issue is that the AC safety system and controls are bypassed- it's not routed through the AC Amplifier, pressure switch, etc. I'd like too get it back to working order but need some help with what i am looking for. The plug is still on the AC amplifier. Not sure what else I am looking for. Any advice, especially pictures would be appreciated! Meanwhile, I'll be googling
tmxmotorsports
SILVER Star
Take the resistor out of the ac amplifier as mentioned in ac amp thread hook factory wire from ac amplifier ro the gm ac compressor and bam that easy dont worry about ac idle up the gm ecm will see a load and idle up some right when the ac is turned on. It will cycle on and off can also adjust the temp cycle on the ac amplifier careful not to adjust it to low or the coil evaporator coil will freeze up.
I’m tackling this over the weekend. I have electric fans with a Dakota digital fan controller. The fan controller has an AC idle up slot. I’ve never worked on a AC system but this seems doable.
Tell me how my plan sounds. Get a drier with trinary switch, remove RPM resistor from stock AC amp, hook up both AC amp and Dakota digital fan control to trinary and run trinary to compressor and a ground? Forgive my layman terms I hope that sounds correct.
Also looking into making custom hoses what are Toyota parts #s that connect hoses to the evap?
Thanks you guys have lots of great info on here
I have a 2uz conversion and used a trinary to control the electric fan. The trinary threaded into my existing drier which I think was stock style.
The medium pressure switch is used to trigger the fan controller (which in mine is 12v+, yours might be a ground) the hi/low contacts safety are wired in to the relay control side. I don’t think most trinarys are rated for the full clutch current and might break if wired directly to the compressor.
The hi/low side of the trinary essentially replaces the stock pressure switch so you can wire it that way.
I have a 62 style amp and left the ignition cut off disconnected with no problems. I suppose cutting the resistor does the same thing in the 60 amp according to the amp thread.
Vintage air has good wiring diagrams that helped me sort this out.
The amp cycles the compressor to prevent coil icing so I agree it’s important to keep it in the loop.
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I just put a small block GM 350 engine on mine and my mechanic indicates that the OEM compressor runs in the opposite direction than the GM motor.
From the posts I see here it appears that it is possible to use the DESO compressor. Please advice.
From the posts I see here it appears that it is possible to use the DESO compressor. Please advice.
- Thread starter
- #60
post #59, probably best you post up a good picture of what your setup is. Why would you not use the GM compressor that fits your engine.. and have some custom A/C hoses made?
my view on GM engine swaps is that you use all the GM accessories that match the engine....don't try and run the items that came off the I6.
I have a 99 GM 5.7 Vortec configured setup and I run all the GM accessories and the Denso A/C compressor that matches my engine (which in my case is something like 96 or 97 through 1999 model year GM pickup and SUV's with 5.7 engine (5.7 vortec)
Recall the OEM I6 ran a v-belt setup.
There are a number of 5.7 or 350 engine configurations over time.... carb,tune-port, tbi, vortec.....
my view on GM engine swaps is that you use all the GM accessories that match the engine....don't try and run the items that came off the I6.
I have a 99 GM 5.7 Vortec configured setup and I run all the GM accessories and the Denso A/C compressor that matches my engine (which in my case is something like 96 or 97 through 1999 model year GM pickup and SUV's with 5.7 engine (5.7 vortec)
Recall the OEM I6 ran a v-belt setup.
There are a number of 5.7 or 350 engine configurations over time.... carb,tune-port, tbi, vortec.....
