i checked the new million pump in the mopar perforce housing. I used a clay like substance on the bevel where the impeller sits closely 2. it is about 1/8th" thick. the blades made no indentation at all so i doubled it up and tried again. they barely touched the clay at almost .25" !!!! that seems like a seriously huge gap between the impeller and housing, this was also without a gasket!

I checked it on the 440 source housing, and you can see it kisses the clay at 1/8" and smashed into it at 1/4".

I ran the 440 source housing, (smaller ports) the new milodon pump and a new highflown 160* T stat.

At idle in my carport it comes to 170* the t stat opens and it drops to 150*ish. when it warms that water up the stat opens again and hot water from the rad coms in and a few seconds later at about 210* the fan comes on and brings everything back down to 170-180* idling fan goes off and then on and so on. it works in the carport.

I took it for a test drive, it hung out around 200*-210* driving. seemed fine there, when i came to a stop it would slowly come down to 190-180* start driving again and it would go back to 200-210*. Maybe it isn't the best radiator? maybe the small ports on the housing don't flow enough water? maybe its a combination of it all.


Now why does it backfire through the carb? from just off idle if i stab it at all it back fires through the carb, i can ease into it no problem.

timing it at 15* at idle. im more of computer tuning guy, never been any good with these carbs. Any advise or insight on this one>???

Sounds like it's going lean if backfiring through the carb. Maybe need more accelerator pump shot...

Is there a way to diagnose this? Or just swap and try again?

Basically thats a trial and error thing.. your timing is locked still right.. advance the timing up to 20*
and try that first

Test, test and test some more until you get it perfect

Timing is no longer locked. Just a billet style distributor

What temp trigger do you have it set at to switch the fan on? Where is the probe located? In the coolant flow or in the air flow?

I run mine in the coolant where the probe sees good flow I think I have temp set at 160*-170*

my fan trigger is in the coolant, it says 185* but its a bit off....
who sells a nice adjustable unit?

Is the bypass plugged in the housing or really small?
Did you accidentally put stat in upside down?

I agree the pop thru carb sounds lean.

It sounds as though the new pump and T-stat are doing their job. The rad is doing it's job of exchanging heat as the temps do drop. Double check the sending unit for its on/off temp. Once that side of the equation is dialed in, you can work on the timing and AFR to finish the problem. An adjustable fan controller may be the ticket here as well??

Also, the last pic you have of your rad shows a shroud. Is it sealed up tight to the rad, or does it have some way for air to move through and then out at speed??

t stat went in correctly, it was labeled

ill check the pump arm tomorrow and see if i have any cams for it.



You guys are awesome, I do not know what I would have done without all of your help!!!

I bought mine at the local auto parts store... its a reputable part supplier.. I can get the
part number in the morning

i did a quick search on the temp fan controller. it says it turns the fan on at 185*-215*. quite the range.

but yes, id like to be able to kick that on, maybe a manual toggle switch too? how do I do an ignition switched ground manual switch? LOL.

Thats pretty easy.. you run a wire from a positive source to the hot on the controller and ground the negative...
I have one on my hot rod for when I run at the track.. if you wanted to you can have it on a timer so it shuts
off on its own

The shroud is riveted tight to the radiator. I don't think much if any air can escape it.

this is the "restricted" 440 source housing

this is the MP version, the one i did not use, due to the impeller sitting further away from the housing.

What is initial timing and what is advance all in?
What rpm does the advance come in at?
What rpm are you cruising at?
Maybe a plug pic? after a steady cruise pull over and pull plug

Have you adjusted the idle mixture screws to make it run little rich see if that helps?

I haven't checked all in timing... I know I know.
cruising it at 2000ish. low speed, no issues there, its just off idle pop.
ill post a plug pic later today

I tried to find a PN on the temp controller but I would have to pull it off to see it.. not gonna do that.. the
parts store should have the numbers.. try a couple parts stores to see if they have a few different ones