Hello,, I have a question, I am to the point of building my coolant setup on my 331 Industrial engine with one of Matt at Geardrive 4x2 setups. I notice that some of the rear water intakes on hemis are just a crossover. I am going to build a setup like brian bass did with a pipe outlets to feed front with a remote thermostat. I could feed the back ports with the same remote feed. The intake is the same one here in Jason Graham built sedan notice the rear crossover. I am wanting to feed the rear crossover with coolant from the remote housing.. Hope you understand my question is the rear crossover needed to keep coolant at temp? Thanks for any input Brad
The rear cross over helps with circulation and even temps across the engine. With a heater core, the rear end of the heads feeds it and is circulated into the suction side of the water pump. So if you wanted , run the rear cross over into the suction side of the water pump and it should work nicely. What water pump are you running Chevy or Chrysler? How about more and better pic of your manifold?
yea thats what I was thinking. I am running the HHheads chevy setup on the front.. The heads that are on this engine dont have the front and rear water intake on them they are solid. Here is some pictures I have to figure this all out before I weld it all up and rebuild the engine.. also I can do two different sizes of water intakes one pipe is 7/8" and one matches the Walker radiator size at 1.5"
Looking at the pics of you engine, the water circulation would be from the lower radiator, through the water pump into the block, exiting the heads and back to the radiator..right? That being the case, and in the absence of a heater core, I fail to see how a crossover at the rear would be of any benefit to circulation. Each cylinder bank is fed by one side of the water pump and connecting both sides of the rear outlets seems to me it would present a 'stalemate' of circulation...roughly equal pressure from each head meeting in the crossover equals no movement in that chamber. Any water exiting the heads would be through the front outlet. Chryslers that I have seen, with manifold flange water circulation ports, often connect the rear outlets with the front outlets on the same side and the combined flow joins the flow from the other bank in a remote thermostat housing and on to the radiator. That would seem to me to best promote full circulation through the heads. The '51 thru '54 Chrysler 331s, like your Industrial model, had no ports on the extreme ends of the heads and used a 'wet' manifold with the thermostat housing built in and returned water to the radiator from that point. I do not recall that that manifold design had a crossover passage at the rear flange ports. The '55 up head design had the ports on the ends of the heads and water exited from the front ports into the water manifold, the intake itself was 'dry', and did not have water crossover connections. Only an outlet along the manifold flange on one of the heads for a heater hose as noted in a previous post. So, except for the limited heater feed, all the water from the heads exited the front port. I may be mistaken, and will consider reasoned opinions to the contrary, but that is how it looks to me. Ray
Is a rear crossover needed? Not really. But it isnt going to hurt either. If you decide on a rear crossover as in the first picture, keep it smaller in diameter than your front inlets. The same if you want to run separate l&r water from your thermostat housing to the back of the heads. In the past, I made these for the heads with no outlets in the ends.
As Ray stated. On most of the early hemi intakes, the only reason water was in the intake was to supply heat under carb. And some, like the Dodges, had no water in the intake at all.
awesome,,, thanks for the wealth of info guys! yea this was a grey area for me looking at all the different setups and years of hemis.. for what its worth I do plan to put some sorta heater in the cab so running those hoses off of the chevy pump like it normally would be my option right? TRWaters, yea I have seen those, I am thinkin the 7/8" crossover on back then matching the size of the radiator port on top of the radiator that is 1.5" is a good deal. I dont think I will weld the crossover solid but weld a 7/8" bung to hook a hose to would be better. Then I have options of crossover/heater etc.. I have seen several hemis on here with that particular setup and I****ume its workin for them. Nice to hear from some guys that have similar setups how cool they run in 100 degree heat at idle etc..
You COULD attach water tubes to the base of your center plenum tube and circulate water through them, supplied by the rear flange port, through the 'heat tube' and feeding into the front port outlet or thermostat housing for circulation. Actually, you might want to bypass the thermostat for quicker warm up of the manifold if you did use such a configuration. Ray
update,, here is what I ended up making.. built a thermostat housing and made some metal tubes to connect front coolant connections.. I still need to build the crossover for the back
With a heater core the coolant is losing some heat, so feeding it back into the suction side of the pump makes sense. Lacking a heater core, and running the rear crossover into the suction side of the pump is just circulating heated coolant through the engine. Probably wouldn't be an issue, but likely better to connect the rear crossover to the front, just below the thermostat.
Remote t-stats take a very long time to get to operating temperature since the only exposure to the heated water is a small 1½"ø surface, and in the case of this OP's configuration, it is in the air stream and the tubing will***** a lot of heat from the water. When mounted in/on a cast iron manifold the iron transfers the heat. In the OP's design a ¼"ø hole will be needed in the thermostat itself to allow for some water movement. .
the tubing for the thermostat housing is connected to the manifold with a mount that is hard to see in the picture. This will help transfer some heat.. With the 1/4" hole will the thermostat still function as needed? its all a shot in the dark for me untill I fire it up.. I was using what Brian Bass created above and the Jason Graham engine which are obviously proven systems already installed and I do remember Brian saying something that he ran his with no thermostat and it would heat up on 100 degree days then after he built the housing it runs 180 all day long no matter the temp.
The problem, in this conversation, is that the thin wall tubing radiates heat very well. Having a bracket mounted to the rest of the thin-wall-tubing manifold is not going to transfer much heat until everything is already up to operating temp. Having all of the tubing hanging out in the wind stream (from the fan) will keep heat from building up, which would actually be a good thing if we were discussing air charge density. The hole in the t-stat allows a little water to move past the spring and eventually some of the heated water will act on the t-stat spring. .
if it was me i would run lines from all 4 water ports to a thermostat housing (speedway and hot heads sells them)with a fifth house run to the water pump as a bypass just like the big blocks had
Good thread, i will be going thru this soon on my 53 311. I believe brain is running a Cragar aluminum 4x2 intake rather than and log if that makes any difference.
Yep Ive toyed with the idea.. That is why I did not build the crossover on the back. it would look cooler too with all the hoses and piping. I will run a heater too so I have to consider everything.. Trial and error I guess... alot of factors play into this. Im going to ask Jason Graham how his setups work with crossovers. He has built some with no thermostats too. Ill get back
The engine in my avatar has the front and rear ports tied together running to a remote thermostat. You can see it if you look hard at the picture. This is in a dirt track car with a built engine and a '65 valiant radiator and a 180 degree thermostat. The only problem is that I have to start the engine and let it warm up for 15 minutes before each heat to get it to the proper temperature. ( I don't have a heater.)
It only makes sense that venting hot coolant from the front and back of head would give a more even temp across the head. But now, maybe it makes about as much difference as******** in the ocean and saying that you've changed the amount of water. They cobbled this up 62 years ago at the chrysler engineering dept
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