5.7/6.1 hemi temp

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5.7 hemi

5.7 hemi

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Some of you may have seen my thread on FBBO, late model hemi into early b bodies, and now that I've been driving it for a few weeks I have this nagging question/problem/maybe nothing to lose sleep over it.

My temp is running at 210 give or take a few degrees. I first started off with the factory 203 thermostat and a 195 on 180 off fan temp sender. The fans would not shut off going down the freeway, so I bout another oe thermostat this time rated at 195 and switched to a 210 on 195 off fan temp switch. Now the fans cycle like they should and the temp is running 210, and it will go 215 or so and the fans will kick on, temp comes down to 210ish and then they shut off. They wont come on going down the freeway, but will cycle in town as they should.

I have a Northern radiator, dual 10 inch Spal fans, have flushed the block 4 times, and always used new coolant 50/50 mix. Should I be concerned or just drive it and enjoy eating unsuspecting ferds/chebbys? Any comments or thoughts would be appreciated.
 
203 is the stock temp. They don't come close to overheating untill close to 275. The Hemi has a fairly efficient coolant flow through the block, I would not worry about it at all. If your in the low 200's your good. You could always swap in a 185 t-stat though. Alot of guys do that on the rams. It's supposed to add a little power. (1-2hp would be my guess) that is assuming your running a stock PCM.
 
Its funny, both the t-stats are 203 and the part number says 195, go figure. Yeah I have a stock computer(s), its an 03. I did put a tune on it with Hyperpac, but the 03's dont do as much as 04 on. So I guess I'll just drive it, enjoy it, and see what happens when summer hits. The minimal hp gain isnt what I'm after, just a nice well rounded combo...car and modern drive train. Buy the way, for you guys doing this type of swap, once you hit the gas for the first time and your eyes suck back into your head, you get pinned to the seat and the front rises some, you'll think every busted knuckle,cut scrape, metal in your eye(s), (it happended to me) it will all be worth it.
 
I use the 185 T too and have nö Problems on the Autobahn with highspeed. Never above 210 F. Speed average 110 Mph. Stock abody sb radiator
 
5.7 hemi said:
Its funny, both the t-stats are 203 and the part number says 195, go figure. Yeah I have a stock computer(s), its an 03. I did put a tune on it with Hyperpac, but the 03's dont do as much as 04 on. So I guess I'll just drive it, enjoy it, and see what happens when summer hits. The minimal hp gain isnt what I'm after, just a nice well rounded combo...car and modern drive train. Buy the way, for you guys doing this type of swap, once you hit the gas for the first time and your eyes suck back into your head, you get pinned to the seat and the front rises some, you'll think every busted knuckle,cut scrape, metal in your eye(s), (it happended to me) it will all be worth it.
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Well if yours sucked your eyeballsback in your head mine should spit them out your toes. Mine will be stroked with twin turbos. (although considering a single now do to space)
 
Some exaggeration, but you get the point.
 
It's all good just messing with ya. There is nothing like Hemi power. That is for sure.
 
Temps are perfect. Since the fan is able to bring the temp back down, it tells me the cooling system is working as it should. The factory has the temp that high for a couple of reasons. First, higher temps greatly reduce engine wear. Second, higher temps, and the right tune help with emissions.

Regards,

Joe Dokes
 
5.7 hemi said:
Its funny, both the t-stats are 203 and the part number says 195, go figure. Yeah I have a stock computer(s), its an 03. I did put a tune on it with Hyperpac, but the 03's dont do as much as 04 on. So I guess I'll just drive it, enjoy it, and see what happens when summer hits. The minimal hp gain isnt what I'm after, just a nice well rounded combo...car and modern drive train. Buy the way, for you guys doing this type of swap, once you hit the gas for the first time and your eyes suck back into your head, you get pinned to the seat and the front rises some, you'll think every busted knuckle,cut scrape, metal in your eye(s), (it happended to me) it will all be worth it.
Click to expand...

Boy, can't wait to see what happens in a car that is 500# lighter than yours...:cheers:
 
Just read an article about cooling. This guy writes in and asks if the 1-1.5 inch space between his lower core support and radiator will upset the airflow, and the answer he got was YES!! So I look at mine and wouldn't you know, I have the same problem as the writer. So I fab up a few brackets, get some 1/2 inch thick pliable high temp rubber and seal that space off. Test drive confirms that now all the air is going thru the radiator cause the fans never came on going down the road. Also my trinity shows the temp to be 204 and my fans are set to go on at 210. Glad I found that article!!
 
So out of curiosity, how low is too low for temps? Right now mine runs stone cold humming down the road, something like 170 most of the time. Not sure if my thermostat is a 160 or 180 though, would have to pull it and double check. It seems like I might have a little more crankcase blowby than I'd like looking at my air filter and PCV connection, wondering if this might have something to do with it.

For those that don't know, the thermostat is the same physical size as a plain small block one. That's how I have such a low temp one in there. Had the 318 out and didn't really want a 203 stat in the car so I figured I could check the sizes for fun. Sure enough, the stats are the same size, so I went ahead and swapped them. Better than paying the $40 or whatever for the "performance" low temp Hemi one in the parts book.
 
Well my point I was trying to make was that the air going thru the radiator was being deflected down instead of going thru as it should, and now I'm a happy camper!
 
Just remember guy's,When I did my change out in my duster,The Hemi t-stat is a dual acting thermostat if I remember right,it not only opens on temp rise but also pressure within the cooling system can open it hence the Dual acting thermostat,SO I don't believe they are the same as a standard small block stat,The factory stat is a 210 degree stat If I remember right,I switched mine to the 180 degree and have a afco alum radiator and a black magic fan pulling in thru the radiator and have absolutely no issues at all--just putting it out there---Steve
 
Huh, didn't know about the dual acting thing. Not sure how much it matters in the long run, but interesting to know either way. Mine seems to run fine with the small block stat, but I may change it out one of these days to something more appropriate.
 
Mt radiator is sitting on the support.. but I have a custom fan shroud that VRC made me that covers the entire back side. Not to mention I a heat exchanger and transmission cooler in front if it too... but I have yet to see over 170's
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