RamRunner Refresh

[posford]

still need to determine your radiator inlet/outlet temps before pulling triggers on anything. Another thought I had was, with your high-flow pump and 165* stat it is possible you're flowing coolant through the rad too fast - not enough time in the rad to pull out the heat. Just a possibility, but gotta git those rad temps - that'll tell all.

I already suggested that in post 73

This is a myth.

Here we go

 

[Bebop]

Here we go

Exact same concept as saying that giving a radiator cold air too fast is a bad idea.

 

[posford]

Exact same concept as saying that giving a radiator cold air too fast is a bad idea.

Fuckin what?

The important bit is the delta between inlet and outlet temperature of the radiator and the relation between the engine and radiator. Coolant too slow and the engine cannot shed heat fast enough, coolant too fast and the radiator cannot shed heat fast enough. It's a balancing act.

Nobody cares about the possibility of excessive delta of the air passing though the radiator because that air isn't related to any other components.

 

[Bebop]

The important bit is the delta between inlet and outlet temperature of the radiator and the relation between the engine and radiator. Coolant too slow and the engine cannot shed heat fast enough, coolant too fast and the radiator cannot shed heat fast enough. It's a balancing act.

That's not how thermodynamics work.

https://www.pmengineer.com/ext/resources/PME/2017/September/008-012-pme0917_Siggy.pdf

 

[posford]

That's not how thermodynamics work.

https://www.pmengineer.com/ext/resources/PME/2017/September/008-012-pme0917_Siggy.pdf

You fuckin hammerhead, that article has a chart that literally shows that temperature drop across the baseboard heater was reduced with increased flow. That exactly what we're saying. As the rate of flow increased across the radiator the temperature drop is reduced.

Thanks for confirming my point.

 

[Bebop]

You fuckin hammerhead, that article has a chart that literally shows that temperature drop across the baseboard heater was reduced with increased flow. That exactly what we're saying. As the rate of flow increased across the radiator the temperature drop is reduced.

Thanks for confirming my point.

Thanks for confirming that you can't read.

 

[posford]

Thanks for confirming that you can't read.

If you think comparing heat output of a home heating system to a water cooled engine is an intelligent argument, then I don't know what to tell you. I don't have the crayons and construction paper to explain in a way you'd understand.

 

[arse_sidewards]

I hate to say it but the filthy frenchman is right. The lower the temp change across the core or the engine the larger the temperature differential between the coolant and the object it's cooling/heating and therefore the more cooling/heating that will happen. Not sure if I explained that well but I don't care.

 

[Mad Max]

...the bottom line is if the outlet temp of the radiator is really high (presumably above the thermostat's operating temp...which is asking a lot of a 165*), then the system will never be able to cool the engine like you want, whether that be because of not enough airflow (fans), size (capacity), the coolant itself. If the outlet temps are good tho, then the bigger question is why is the engine making so much heat. I know it's the captain obvious stuff, but this is what helps me keep things clear.

Don't know if you drive the truck on the street, but if so does the engine run cool? IOW, when there's lots of airflow and not much 'demand' are you having the same issues?

 

[Will Scarlet]

 

[75RamRunner]

Alrighty i have data.

First off

Existing fans were Spal 18s, confirmed a data tag on them, there "1000 cfm" fans for what its worth and draw 10.1 amps. so as previously mentioned. They suck

New fans draw 18.3 amps and are "3000 cfm fans"

All the below data is at 102 degree ambient temp. I got extra ball sweat just to get accurate date for you fucks during the times that I'm most concerned with

MSD temp sender is in the water pump housing front cover close to the pump
Autometer send is the the top of the water pump housing going into the block

Stat opened at 167ish so 165 stat does what it should
Coolant out temp hose was 170
Coolant in temp hose was 134

Let it idle for a bit and stabilized

MSD temp says 196
Autometer temp says 200

Took it for a street ride, 3500-4000 a couple times, 1-5th and back a few times, back into shop

Coolant out hose temp says 185
Coolant in temp hose says 151
MSD says 222
Autometer temp says 226

 

[Bebop]

Alrighty i have data.

First off

Existing fans were Spal 18s, confirmed a data tag on them, there "1000 cfm" fans for what its worth and draw 10.1 amps. so as previously mentioned. They suck

New fans draw 18.3 amps and are "3000 cfm fans"

All the below data is at 102 degree ambient temp. I got extra ball sweat just to get accurate date for you fucks during the times that I'm most concerned with

MSD temp sender is in the water pump housing front cover close to the pump
Autometer send is the the top of the water pump housing going into the block

Stat opened at 167ish so 165 stat does what it should
Coolant out temp hose was 170
Coolant in temp hose was 134

Let it idle for a bit and stabilized

MSD temp says 196
Autometer temp says 200

Took it for a street ride, 3500-4000 a couple times, 1-5th and back a few times, back into shop

Coolant out hose temp says 185
Coolant in temp hose says 151
MSD says 222
Autometer temp says 226

IAT 149?
Any way you could fix that ?

I'd still put some real fans on it.

And finally, for arse_sidewards to admit I'm right, I have to be doing something half-decent cause I know it cost him. Tip of the hat, gentleman

...the bottom line is if the outlet temp of the radiator is really high (presumably above the thermostat's operating temp...which is asking a lot of a 165*), then the system will never be able to cool the engine like you want, whether that be because of not enough airflow (fans), size (capacity), the coolant itself.

Nope. Try again.

 

[75RamRunner]

IAT 149?
Any way you could fix that ?

I'd still put some real fans on it.

And finally, for arse_sidewards to admit I'm right, I have to be doing something half-decent cause I know it cost him. Tip of the hat, gentleman


Nope. Try again.

Yeah intake air is ugly. Just have a standard 14" air cleaner on top of the TBI. Been thinking about routing some ducting into the cowl as a CAI of sorts.

Could just roadkill it and take the hood off

Headed to the Rubicon Friday these fans are the highest amperage i can get that fit in the space. Mo better?

SPAL Automotive USA IX-30102120 Spal Electric Fans | Summit Racing

Free Shipping - Spal Electric Fans with qualifying orders of $109. Shop Fans, Electric at Summit Racing.

www.summitracing.com

 

[Bebop]

Yeah intake air is ugly. Just have a standard 14" air cleaner on top of the TBI. Been thinking about routing some ducting into the cowl as a CAI of sorts.

Could just roadkill it and take the hood off

Headed to the Rubicon Friday these fans are the highest amperage i can get that fit in the space. Mo better?

SPAL Automotive USA IX-30102120 Spal Electric Fans | Summit Racing

Free Shipping - Spal Electric Fans with qualifying orders of $109. Shop Fans, Electric at Summit Racing.

www.summitracing.com

This is what you're asking about :

I would look at this guy instead, if you can fit it:

SPAL Automotive USA IX-30102082 Spal Electric Fans | Summit Racing

Free Shipping - Spal Electric Fans with qualifying orders of $109. Shop Fans, Electric at Summit Racing.

www.summitracing.com

Same electric motor, but the blades are a lot better and the tradeoff in thickness is minimal (about 0.3").

 

[75RamRunner]

EDIT: I'm a tard and the model number is one different than the one i looked at. That does look like it'll fit fine

 

[Bebop]

EDIT: I'm a tard and the model number is one different than the one i looked at. That does look like it'll fit fine

Cool. That's the one under the big fan I'd have liked you to run.

Edit : I still think this is better, but if it doesn't fit...

SPAL Automotive USA IX-30102803 Spal Electric Fans | Summit Racing

Free Shipping - Spal Electric Fans with qualifying orders of $109. Shop Fans, Electric at Summit Racing.

www.summitracing.com

 

[75RamRunner]

Cool. That's the one under the big fan I'd have liked you to run.

Is the 30 degree differential in the inlet/outlet temps from the radiator low?

I also think the fans are playing a huge role in the IAT as they're shoving hot air right into the engine bay and with no fenders and fenderwell headers the heat seems to be getting trapped up by the intake. I'm going to pull the hood off today and run it around and see what it does while i wait for the fans

 

[slow600]

this ride cold pull off hood louvers, just saying

 

[Bebop]

Is the 30 degree differential in the inlet/outlet temps from the radiator low?

Again, doesn't matter.

The only thing that matters is to compare the outlet temps in identical conditions with different fans on.

I am all for a hoodless run. Will probably fix any airflow issue.

 

[75RamRunner]

this ride cold pull off hood louvers, just saying

Well i might as well go with the bird catcher/tunnel ram combo at that point

Louvers in the bird bath portion of the hood may not look so bad...

There really isn't much OG sheet metal left so I've been trying to not completely remove the truck looks to it but defintley not opposed to getting some air relief

 

[Mad Max]

Coolant out hose temp says 185
Coolant in temp hose says 151
MSD says 222
Autometer temp says 226

so the 'hottest' coolant out of the block/into the radiator is 185* (on the hose), and coolant out of the rad/into the block is 151*, but the temp senders in the pump housing are reading ~40* hotter..? That seems pretty strange, especially on the inlet side. I'd think the water pump temp sender on the inlet side should ready pretty close to radiator outlet temp, and the pump outlet port should read on the outlet temps...but if your rad outlet hose is only reading 185*...that's just really strange. I don't remember which of the pump housing ports...

...wait wait wait - lemme ask this - do you by chance have an RV pump housing? Look at the info below from a 440 build I did a while ago - bottom line is if you have an RV housing you MUST use the matching RV 'stat. I had an RV pump housing and unknowingly ran a non-RV thermostat...and it always ran 'warm'; I put the proper RV thermostat in it and it cooled solidly at thermostat temp ever since. check this out -

My particular 440 was date coded 1978 and was originally in a 79 Winnebago Motorcoach, and because it was intended for an RV is actually has a few minor but important differences between it and a standard car or truck 440. First, the RV 440s were designated at a 440-3, whereas the car/truck 440s were 440-1. The major differences were mostly related to cooling, meaning two additional cooling ports at the outer edges of the cylinder walls, with (or in my case without) respective matching heads with the additional cooling ports, and, the big distinctive difference, the RV heads had 5/8 spark plugs with a non-crush-washer seal (my heads are the typical 440-1 452s with the normal 13/16 plugs and crush washers, so either my 440 just didn't get 'em...or more likely the owner of the RV had the heads swapped out for non-RV heads - my engine did have Fel-Pro head gaskets on it, which was not original, so a head swap was most likely). Also, the RV 440s also received a specific water pump housing, pn# 3751216, easily distinguished by either the CB on the front inlet or the additional bypass port under the thermostat, which I discovered is kinda important.

RV water pump housing (note the two cast recesses for the thermostat and bypass port) -

A "skirted" thermostat must be used in conjunction with the RV water pump housing - at least it does if you want it to be cooled properly. The RV pump housing has a 'bypass' feature, which with the RV thermostat...when the engine is below op temp...is intended to prevent coolant from circulating into the radiator and only let coolant simmer in the block until the stat opens (the intent being to warm up the block rapidly for cabin heat, etc.), but when the stat opens then blocks the bypass port, sending all of the coolant to the radiator. The RV 440-3 thermostat (I opted for the Milodon 180* unit, #16406) has a lower 'skirt' which when opened blocks off the bypass port in the water pump housing, but without which (with a typical 'B-body' etc. thermostat from the parts stores) will not block the bypass port, which will not send the majority of the coolant to the radiator - it will just continually 'churn' within the block/heads...and some will go through the radiator, but not all, which is why my 440 wasn't cooling well (it was cooling so-so, but not great) - and yep I had a standard 440-1 thermostat in there.

It is also possible you have the RV stat in a standard non-RV housing...which I can only presume will work equally as bad, the presumption being the non-RV housing requires a non-RV stat, like every big block Mopar would have had.

Pics of the skirted thermostat are below -

To recap, here is my RV water pump housing -

But wait - there's more. All of the upper thermostat housings I've found have a recess in them too, which according to the books is to center the thermostat in the 440-1 non-RV applications. The strange part is my 440-3 water pump housing also has a recess for...I think...the thermostat. Now, because the thermostat lower skirt is supposed to extend down into the lower recess and block the bypass coolant flow I chose to presume the thermostat is supposed to be placed in the pump housing itself, and not in the upper thermostat housing. Should the thermostat go in the upper housing? - don't know, but if it did then there would be the chance of it not aligning with the lower recess, so I went with the lower/below-the-gasket placement. Then, UltraGrey RTV, gasket, more RTV, and upper "thermostat" housing went on, bolted to 18 lb/ft. I'm pretty sure my thermostat housing is not for an RV application and is simply for all the 440-1 applications. I have not yet found a genuine 440-3 thermostat housing, but if I did I'd wager there is no recess in it for the thermostat.

But still, my thermostat housing had that recess in it...or at least it used to. To try to get maximum clamping and sealing potential from it I went ahead and had a local welding shop fill in the recess (cast iron), and I machined it flat - actually I machined it to perfectly match the pump housing with just the slightest detectable amount of center 'rise' to get that much more clamping on the gasket. So, just posting my process and pics for it all...

Upper thermostat housing 'filled in' -

...machined flat -

I got the Milodon thermostat, skirted/RV design (silver), compared to the less reputable Mr. Gasket version -

and Permatex 27036 ultragrey to seal it all up -

 

[Levigarrett76]

Holy shit^^^




Anyone have an idea what is considered a normal/acceptable temp drop across a radiator?

 

[rattle_snake]

Depends on ambient temp and airflow.

As for IAT, it's not a big deal to have high IAT at idle/stopped. What does it read when you are moving, engine under load?

I was going to build a fancy cold air system (not quite to 'blue jeep' level) but first I measured temps. Once rolling the IAT was only 12 above ambient. So a lot of work for minimal gain.

 

[75RamRunner]

Mad Max and I thought I was a Mopar nut

This engine is running an aluminum passenger outlet water pump from 440 source

Water pump housing Aluminum - Passenger Side Lower Hose

Finally, a part that customers have been begging us to make for years! An aluminum water pump housing that exits on the passenger side instead of the drivers side. Now you can have your choice of which side you want your lower hose to exit. In the past, the only housings available with a...

store.440source.com

And one of their recessed upper necks, very informative wall of text i didn't know about though!

Also running 906 heads on this block and its a true tnt bottom end so im hoping to not totally grenade it and put it in a 68-70 B body one day.

 

[Mad Max]

Mad Max and I thought I was a Mopar nut

This engine is running an aluminum passenger outlet water pump from 440 source

awww biscuits - man I was so hoping you had the same cooling paradox I had, with it's super easy fix. I guess the 440 Source housing could be an RV style but I doubt it - haveta look down its throat to know for sure...but yah unfortunately it sounds like yer still at square one

 

[75RamRunner]

Got those Spal's on last night, thats about the max room i have, its hard to tell but one of the shock tower braces is rubbing on the fan housing pretty bad. I don't see it being an issue for performance but any deeper is going to require rework of the radiator mounts and recessing into the core support

Idle after start-up and stat stabilzed

Inlet temps

Outlet temps

After the exact same road loop as sunday

Outlet Temps

Inlet Temps

I noticed the other day that two of the spark plug wires had burned through on the headers

Ran these bad boys on the last setup and figured i had clearance on the new headers, so i made two of them up real quick, ill end up switching them all over eventually

So i did notice that the cooling works way better just above idle, which makes sense the water pump is spinning faster and moving more water. These fans seem to be able to hold temp good and actually bring it down under light load. At idle the temps creep when I'm in gear and on the brake. They'll immediately drop 3-5 degrees if i bring it up to 1300-1500rpms.

These fans also pull every bit of 40 amps, popped one of the fan fuses when it tried to spin over.

I do feel that the jump from the stock ones to the flex-a-lite fans (18ampers) was a bigger notice in performance than the jump to these 40ampers but if they work they work, that's all I'm after.

 

[Bebop]

Try to get a higher flowing pump

 

[75RamRunner]

Try to get a higher flowing pump

Has the only high-flow pump i know of that fits in a BBM water pump housing. was going to look into a smaller pulley for the water pump to overdrive it a bit, i dont spin this thing past 5800rpms so something like a 20% smaller one shouldnt overdrive the water pump to orbit.

 

[Bebop]

Has the only high-flow pump i know of that fits in a BBM water pump housing. was going to look into a smaller pulley for the water pump to overdrive it a bit, i dont spin this thing past 5800rpms so something like a 20% smaller one shouldnt overdrive the water pump to orbit.

yes that's a great idea.

 

[Mad Max]

...personally I would actually recommend going with the RV housing and thermostat - IMPO it's the very best big block Mopar water pump setup available - the housing and the bypass port design is the real magic, and I also think the RV thermostat is capable of flowing a lot more coolant than the car version.