Factory Five Racing Forum banner

1 - 20 of 43 Posts

·
Registered
Joined
·
1,379 Posts
Discussion Starter #1 (Edited)
I've been reading the post on the both the expansion tank and 4-port heater control valve (HCV) cooling system modification. There are two primary threads that are extremely long reads and, at least for me, gave great information but also made it hard to draw a clear picture of what is specifically connected, disconnected, removed and/or added. http://www.ffcars.com/forums/showthread.php?t=242898 and http://www.ffcars.com/forums/showthread.php?t=235842 are the two threads I am referring to.

Crash and Richard did the R&D for this system so the credit goes to them. I just wanted anyone looking for the mod to be able to find, understand and then know exactly what parts are needed and how to add it to their GTM.

Attached is a quick diagram I created using MS Art. Crash / Richard and anyone else how has the knowledge on this mod, please take a look at the diagram for corrections. I know there will be more ways to complete this mod and the diagram is based on the two threads and some detailed info from Crash that I was gathering iot complete the mod on my build. So please try to keep the corrections on track.

If you have questions on alternatives, deviations to this mod or just want to know why, the two referenced threads have the answers. This will keep us from just repeating the info from the other two threads. Thanks.

Quick HCV and Expantion Tank Diagram
 

·
Registered
Joined
·
1,221 Posts
The NAPA #CRB 219226 valve needs a pigtail. There is a NAPA number for this, but it is also available from Summit Racing as pico 5605pt. I believe that it is also the same as the connector for the evap controls from the Corvette, so you might have an extra one from that.

Vidal, thanks for condensing those long threads into something easier to access. Years ago there was a very long thread on how to hookup the Vintage air to the Corvette A/C. When it was all said and done, it turned out that it was as easy as hooking up 2 wires.

Mike
 

·
Registered
Joined
·
16,313 Posts
Yep, you pretty much got it there.

This is what you will end up with when you order my complete cooling system kit.

Canton Tank
Radiator Cap
Tank TEE fitting
Tank Head Fitting

Bypass Valve
Vacuum Valve
Hose Adapters
Vacuum Line
Vacuum Valve Specific Electrical Plug

All the parts will be included, along with instructions and pics of how to install. The costs should be around $80 for the Heater Bypass Valve uprade kit, and around $160 for the Header Tank Kit.

They will be available here:

http://www.myraceshop.com/GTM-R_Pieces.html

once all kits are thouroughly tested and clear instructions are available.

I am not trying to make a ton of money here, just trying to make it easier for builders like yourself who may not be exactly clear what they need or for those that may not want to spend the time tracking down all the neccessary parts.

Thanks for the interest, and, as always, I am happy to try and answer any questions.
 

·
Registered
Joined
·
425 Posts
VD2021:
Thanks a million for consolidating all the typing into a picture I understand.
Crash:
If this is how your system works and it eliminates the front tank, then sign us up for the full system with tank.
 

·
Registered
Joined
·
420 Posts
Keep in mind that you can run without any HCV valve as long as you keep continuous flow through the heater "circuit". Now that crash has made it simple to source and implement the correct valve, its no big deal, but it is an option.
 

·
Registered
Joined
·
1,379 Posts
Discussion Starter #6
VD2021:
Thanks a million for consolidating all the typing into a picture I understand.
Crash:
If this is how your system works and it eliminates the front tank, then sign us up for the full system with tank.
Steve,
I started plumping my cooling and AC systems right after I installed the transaxle and have been searching, reading and asking question (thanks Crash) since then. It was frustrating and confusing. Just when I thought I had figured it out, I would read something that set me back into cconfusion and more frustration. This forum is giving to me constantly and I just want to do my part. I guess you can thank Crash in two ways; one for R&D and two for having sold out of his beta kits.....:001_smile:. Because, had he had one for me, It would already be part of my build...
 

·
Registered
Joined
·
18 Posts
Keep in mind that you can run without any HCV valve as long as you keep continuous flow through the heater "circuit".
What would be the issues of doing so? Radiant heat from that part of the climate system? Just asking from a simplicity standpoint, here.

Also, can the expansion tank be put into the main coolant loop? Would that necessitate a different (larger) tank?
 

·
Registered
Joined
·
420 Posts
What would be the issues of doing so? Radiant heat from that part of the climate system?
This is all from memory having spent A LOT of time trying to understand it when it first came up. Others will correct me if I'm wrong. Let me add that the solution crash is offering is a great idea that has been proven to work.

The way the system on the vette was designed to work means that flow past the heater is "shut off" if the a/c is set to max cool. This is to ensure maximum cooling by avoiding radiant heat. As eeny discovered (I think) reimplementing this setup like this in the GTM leads to the water pump thermostat not opening as needed. For some reason, in the GTM it needs constant flow through the heating circuit to open. The valve that crash is offering manages this in an intelligent way, ensuring flow by switching to a bypass mode when max cooling is designated for the A/C. As opposed to the flow being "shut off", it is "redirected", so the thermostat stays happy. The thermostat will also work properly if you run without ANY valve (stock corvette or myraceshop aftermarket). Theoretically, you will get more radiant heat than with the valve solution, but I have no idea if it is noticeably more.

When I was planning a project, I was going to keep it as simple as possible and run without any valve as it doesn't get hot enough where I live to worry about it. Now that the solution has been so clearly defined, proven, and is readily available, I'd probably go with what crash is selling.
 

·
Registered
Joined
·
16,313 Posts
VD2021,

Don't you stiil need the rad steam port?

Mostafa
No steam is generated in the radiator, and a small pocket of air in there is not really an issue as far as damaging anything. It can be bled out at install when initially filled by un capping the radiator steam port until fluid comes out. Then all should be good unless you open the system up again. We open the system frequently on the PDG GTM so we have put in a petcock for ease of bleeding, but this isn't really required. Once the radiator is bled, then a cap will work just fine.

The tank in the rear allows the engine to become "self venting" and thereby eliminates the air pockets getting stuck in the heads of the engine and causing a very serious "spiral of death" scenario whereby the air pocket does not allow the head to be cooled properly, then the engine heats up even more in that area, more air is "created" by boiling fluid, the air pocket gets bigger, the head heat gets greater...I think you get the idea? If this continues then either the car overheats and spews fluid out the cooling system, or you end up losing a head gasket. This is precisely what the Header Tank Kit addresses, and why I think it is an absolute must have, but also why I want to be absolutely, 100% sure that my solution is THE solution and that everything is setup in the kit for a "bullet proof" install by the GTM builder.

These kits ARE coming. I just ordered 5 tanks yesterday. :)
 

·
Premium Member
Joined
·
507 Posts
This looks like the solution AllanFFR has been using on his GTM and the other GTMs he's built from years back. I think he posted about it a long time ago as well. He's built them both with the Corvette tank, and the Canton with the proper fittings.

It works very well. No air/overheating issues with over 7000 street miles.
 

·
Registered
Joined
·
16,313 Posts
This looks like the solution AllanFFR has been using on his GTM and the other GTMs he's built from years back. I think he posted about it a long time ago as well. He's built them both with the Corvette tank, and the Canton with the proper fittings.

It works very well. No air/overheating issues with over 7000 street miles.
Yep, and I have used it for over 20 years in various race cars, so the theory is proven quite well. It's the specific parts, and getting it into a "bullet proof" type of kit that will be easy for the average GTM builder that I am worried about and why I am taking some time in putting this together.

Granted we aren't dealing with housewives that have never opened the hood of a car here, but in seeing how many people have commented on wanting to put the head vent line onto the radiator cap vent out port, it is very clear that a CLEAR set of instructions, including pictures, is what's needed. I am working on these now. ;)
 

·
Registered
Joined
·
139 Posts
OK - there's always one fish that wants to swim in the opposite direction from the school - so here are my questions: I plan to supply the heater core by tapping off the tunnel coolant piping, instead of taking the lines from the water pump. Simpler piping; less "radiators" in the tunnel. Known downside - longer for the heater to warm up - not a biggie in Houston. So, 1)should I STILL use the 4-port? and 2)are there any other downsides I'm missing? THANKS!! Best regards, Ted Wright #261
 

·
Premium Member
Joined
·
507 Posts
Yep, and I have used it for over 20 years in various race cars, so the theory is proven quite well. It's the specific parts, and getting it into a "bullet proof" type of kit that will be easy for the average GTM builder that I am worried about and why I am taking some time in putting this together.

Granted we aren't dealing with housewives that have never opened the hood of a car here, but in seeing how many people have commented on wanting to put the head vent line onto the radiator cap vent out port, it is very clear that a CLEAR set of instructions, including pictures, is what's needed. I am working on these now. ;)
This kit/solution should work for the SLC and most other low/mid engine kit cars too. I'm all for having a no brainer pre-packaged setup. It's saves a lot of time. Good luck with the kit.
 

·
Registered
Joined
·
16,313 Posts
The four port valve upgrade from the HCV is not a "requirement". As Artgirl said, you can run fluid through the heater core at all times and all will work fine, and this will solve the thermostat issue. However, the downside is that the Vintage air system was designed to use the HCV(supplied Heater Control Valve) to shut off the flow of coolant when the heater portion of the HVAC unit was not being used. What will happen to temps and efficiencies of the Vintage Air unit when in "max AC" mode without any valve being used? I really don't know. Maybe Vintage Air can answer that?

The solution offered just keeps the Vintage Air system operating as designed by it's manufacturer, and also changes things a little so that the GM thermostat is operated as GM designed it as well. So the 4 port valve essentially just makes everything work as intended by the combination of manufacturers of both the AC unit and the engine. ;)

Use it, don't use it, plumb it differently, whatever. As the saying goes, "there is more than one way to skin a cat". If you absolutely know what you are doing and have considered all the potential consequences of changing things, then no problem. Build what you will. I offer this kit simply so that builders can make this stuff work as a "no brainer". :)

And not trying to bash or demean anyone in any way. I am one of those guys that can't seem to leave well enough alone whenever I get something. I take it apart, I look at it for long periods of time, and I try and see if I can come up with a simplier, easier, cheaper, or better way, so I fully understand what you are saying and where you are coming from.

If you do go your route of hooking into the lines that run through the tunnel instead of running lines to the thermostat housing area of the water pump, you will need to make sure that there is continuous flow to both sides of the thermostat. If all else fails, then just run a U tube connecting the inlet and outlet at the thermostat where the Vette heater hoses originally attached. ;)

However, if you want to also address the head steam vent issue, then putting a Header Tank kit on will address this AND allow water to flow to both sides of the thermostat. You can then put the 4 port valve anywhere you like before the heater core, or just use the HCV and just stop flow entirely in the hook up lines for the heater circuit. :)
 

·
Senior Charter Member
Joined
·
675 Posts
OK - there's always one fish that wants to swim in the opposite direction from the school - so here are my questions: I plan to supply the heater core by tapping off the tunnel coolant piping, instead of taking the lines from the water pump. Simpler piping; less "radiators" in the tunnel. Known downside - longer for the heater to warm up - not a biggie in Houston. So, 1)should I STILL use the 4-port? and 2)are there any other downsides I'm missing? THANKS!! Best regards, Ted Wright #261
Ted,,,
I'd like to do mine the same way,,, I'm in Ft. Lauderdale so not too much need for heat here either. That said.... how are you planning to tap into the existing pipes? I'm thinking to tap the pipe that feeds the radiator and tap at an angle so it would want to flow to the heater core,,, but I'm not 100% sure that is necessary. It'd be easier to tap into it at 90 degrees but I don't know if there is enough preasure to force the water to flow to the heater core. AS for the return,,, I figure a 90 degree tap into the return pipe. I'm also planning to use the two port valve that came with my AC kit (non-FFR).

As for the motor side,,, I'm just planning to put two lines to the expansion tank.
 

·
Senior Charter Member
Joined
·
675 Posts
Ted,,
A couple of photos from the GT40 guys as to how they did it.



 

·
Registered
Joined
·
18 Posts
Thanks for the explanation ArtGirl, and I'm pretty sold on the HBV kit now (added to my build budget thread as well). I still didn't get an answer as to whether or not I could locate the tank in the main coolant loop or whether it had to be specifically on the heater circuit.

I'm wanting to do a double radiator setup, and am trying to find out if it is feasible or not. I've attached a rough diagram of what I was thinking of doing (feel free to ridicule the n00b) and it seems sound, but I am not the subject matter expert.
 

Attachments

·
Registered
Joined
·
139 Posts
Fred - I'm afraid I'm not that far along yet - Still wrasslin' with your basic engine to radiator piping. I REFUSE to use those corrugated abortions, so I'm fittin' and fussin' with rubber bends and extra aluminum tubing I bought from FFR. I envision ending up with coolant piping similar to the 90's ZR1 - mostly straight piping with rubber bends. I expect that the pressure drop from the hot side to the cold side will provide enough oomph to drive flow (enough for heat in Houston) through the heater core. I think the final configuration of the heater taps will be driven by the geometry of the layout - I don't expect angle or 90 taps to affect the flow enough to worry about (I DO like the looks of the GT40 plumbing though!!) I'm planning on using an expansion tank in the engine compartment and the supplied heater valve. But, haven't figured out flow pattern to the tank with this config. yet. Any suggestions will be GREATLY appreciated!! Best regards, Ted Wright #261
 
1 - 20 of 43 Posts
Top