My 427 SOHC Build..... Finally the time has come!

[My427stang]

I like the fans to come on at 15-20 degrees higher than thermostat temp then off at 5-10 under.  The 180 stat actually starts to open at 180 but is likely not fully open until 190, if you have them come on at 195-200, it will allow the thermostat to do its job and when it can't solve the problem, the fans will kick in.  Otherwise they will be on all the time.

The FAST system has a turn on temp that is adjustable, and then shuts off 20 degrees below that.  So on at 195 will be off at 175, that should be good with your thermostat.  If they run all the time, you can adjust it to 200

[cobracammer]

Thanks Ross. Ill let you know once I have it all appropriately wired.

Few days off while waiting will do me good. Lol

[cobracammer]

Hey Guys,

Just because I was super perturbed when I was scalded with steaming coolant the other day..... and because I have gotten the "Coolant Fan" issue being taken care of, I wanted to make sure my thermostat "situation" is under control.....  since I am using a Saleen part in a custom way:

Just to bring back the OEM coolant flow diagram:



So obviously this is not exactly how it will work (Figure above), but I am still using the OEM thermostat housing, it still connects to the bottom of the radiator for coolant (IN), still pulls gas out of the top of the radiator (#1= degas tank and #2 is the hose that feeds additional coolant into the system (Its also how you will the coolant up in this car), and the thermostat (hopefully) opens to allow coolant into the Cammer engine water pump.  So this is what the thermostat housing looks like.....  Its actually not even a stock Mustang part, but seems like an aftermarket part that Saleen installs while building the car:



ok so I have this installed so the thermostat bottom (with the spring) is sitting down in this part of the housing: (See below)



The top of the thermostat is sitting up in this portion of the housing: (See below)



The degas tank supplied Coolant into the system down a hose and into this port on the housing (in the same area where hot coolant is sitting awaiting the thermostat to open): (See below)



There was an extra port on this housing that will not be used in my application, so I plugged it with a rubber expansion plug (sold at Autozone for just this reason): (See below)



And finally, this port below is connected to the bottom of the radiator.  It lets hot coolant (cooled by the fans/radiator already) into the housing in which the thermostat (bottom- with the spring) is housed.  Once it gets to 180 degrees, it opens letting coolant from the radiator (and some coolant from the degas tank to flow up into the Cammer engine water pump.  I removed the thermostat I had originally in the Cammer engine water neck so the water then flows freely around the engine, out the waterneck..... through the radiator, and assuming the thermostat in the Saleen housing, back through the water pump: (See below)




Sorry if this is overkill, but I want to make sure I am not boiled like a lobster ever again  LOL  Does this seem correct?

[Heo]

Im no expert on that but i dont see how it works beacuse the cold water
from the radiator is what hits the termostat i want the thermostat
on the outlet of the engine before  the rad. It obviously works on the Saleen
but i should use the SOHC thermostat housing remove the Saleen termostat
but leave the thermostat housing

I would understad it if it was reverseflow....are you sure the arrows is drawn
pointing the right directions. Beacuse i cant see how it works to have the thermostat
downstreem from radiator and feeding it with cooled water

[cobracammer]

Yea .  Not sure how the Saleen made it work at all???  I was just watching videos on cooling systems and what gets me is that you need to fill the cooling system through the degas tank.  Since the degas tank filters down into the closed portion of the thermostat housing (until the thermostat opens) I am basically just filling the radiator up with coolant and none is getting into the engine block.

I think I will take (Like you said) the Saleen thermostat out of the housing (I will leave its Flange as well as the O-ring on so it will still seal water tight)....  I will then replace the 190 degree thermostat in the Water neck of the Cammer engine (This thermostat I drilled 2 bypass holes in).  This should allow me to then pour coolant into the degas tank and it will fill up the engine block as well as the radiator.

I guess what I don't get (cant wrap my head around it) is.... When I fill the system with coolant (after I do the thermostat swap), the radiator , and block will be almost full of coolant.  When I run the engine, the water pump is going to start pumping the water from the radiator (now because the closed thermostat is not down there restricting it) and pumping it around the block....  But it can not escape until the thermostat in the water neck opens and lets it run down the radiator.  Can the Ford FE water pump ever pump enough coolant into the block and before the thermostat opens to release pressure.... cause a blow out?  Or does the engine coolant heat up so fast when you start the car that the thermostat will open fairly quickly?

I checked and the stock Saleen radiator is 3 core and the fans each move 1250 CFM (So 2500 CFM together)....  hopefully that's enough to keep it cool

Thanks Heo

[Heo]

No the wp dont build enough pressure to blow out something
the water will just cirkulate in the block untill the thermostat
open to to let hotwater out to the rad.And suck in cooled water
from bottom of the rad. Its important to dont have a airpocket
behind the thermostat beacuse it wont open and the heat build
pressure and then you have a nice geyser from the filler cap
When i fill an cooling system thats complete empty  i remove the
thermostat housing an fill to i have water up to the thermostat
or remove hose to the heater what ever thats easier

[cobracammer]

Thanks Heo.  I actually disconnected the heater, so I don't have to worry about air trapped in the heater core.  If I ever want to add it back later, I can, but for now, I will only have to worry about filling the block/radiator.  I will do like I did before and fill the car with coolant while the front is up on jack stands.  I will full as much that will go in the degas bottle, and then it stops filtering down into the engine, I will pour down into where the thermostat sits, before I put it back in and replace the water neck flange.

Also, drilling bypass holes in the thermostat that goes in the water neck (which I did already)...  doesn't seem like much coolant would get through those 2 small holes.  Does it really make that much difference in cooling?

[machoneman]

Also, drilling bypass holes in the thermostat that goes in the water neck (which I did already)...  doesn't seem like much coolant would get through those 2 small holes.  Does it really make that much difference in cooling?

The holes have nothing to do with cooling. Might drop a few degrees when hot compared to no holes. The idea is to allow water to flow before start up and eliminate an air pocket behind the thermostat. Drill the same size holes in a water bucket......the water will flow! 

[Heo]

Yes the holes is to eleminate an airpocket behind the thermostat

[cobracammer]

AHHHH  ok.  I always read that its to prevent overheating and My first thought was, "wow, I couldn't imagine that small amount of water getting a head start through the radiator would make a difference.... "  I got it now, that makes total sense thanks!

[blykins]

I would look really hard at your headers. 

I had sent a 347 SBF to a customer.  I dyno'd it with a carb setup, but put a FAST/Inglese 8-stack on it before I delivered it.  They just got it running, it ran for 20-30 minutes, then went REALLY rich and shut itself down. 

My customer's installer has been on the phone with FAST the past few days and one of the questions that they asked was what the O2 sensor data was showing.  Turns out that he had a bad header/exhaust leak and it was showing really lean....so the computer was trying to compensate. 

[cobracammer]

I just contacted the shop owner. He said those headers will not be air tight. He said he can move the o2 bung up one of the primary tubes closer to the engine???  Will that work?  Paid over 2200.00 for these headers. They are a thing of beauty, but are not apparently air tight at the collector.

He texted me just a second ago and said that he runs ton of EFI's on the slip style headers and never has an issue. He is actually going to come over Sunday morning and take a look

[My427stang]

Yes you can move it to a primary tube, but remember, you cannot use any of your prior results for data

1 - You had the TPS adjusted wrong
2 - You fired it a bunch of times and it got hot enough to enter learning with the TPS wrong and changes in fuel pressure
3 - You overheated it giving it bad data
4 - You ran it with low voltage a bunch of times

Again, ignore your old data and just get it running first and staying cool, trust me.  This O2 sensor discussion is like chasing windmills until you can get it running and staying at normal temps, please please please....try to avoid helping or being helped until you have that squared away.  Trust me

I also think the headers are no issue whatsoever, or better said, not a significant issue. 

For the thermostat, why can't you just use a stock style for the cammer and add an inline radiator cap to the upper hose and use a solid lower hose?  Seems like an easier fix, then use the degas bottle as an overflow if you want to keep it

ON EDIT, I think I figured it out..... I think your Saleen part is for reverse flow, there is no way it would get hot water to open the thermostat and the picture you have above seems to show the lower degas manifold without a thermostat. I think that maybe the diagram is for a standard flow, but your car was reverse flow.

You may be able to use the Saleen manifold without a thermostat (leave it wide open)  and add a thermostat to the SOHC water neck up top.  Then it would match the diagram above

Note that I am not talking about fuel mixture just cooling....  and yes I am using my Colonel's voice with with all my bold LOL.  I am the EFI lover in the room, but you HAVE to take one bite of that elephant. 

Matter of fact, I think your visit from the header guy has the potential to cause more trouble if you havent got the cooling worked out.  I'd wave him off if it was mine, at least until the cooling is fixed

[blykins]

Follow Ross' advice, Jason....

I haven't been in on the thread for the entirety, so I'm hit and miss at best with the data.  I was driving in the truck today and called a customer to see how things were going and we had this discussion.  It rang a bell with your initial startup issues, so I thought I would post. 

[WConley]

+1 on following Ross' advice!

Too many balls in the air now, and there are some bigger ones to catch first.  Get that cooling deal under control.  Then you will have a better shot at getting the engine to a stable running situation.

The idea of putting the thermostat in the cammer water neck sounds intriguing...

- Bill