The 408 in the Demon always wanted to creep up past the 200 degree mark, even on long drives down the highway, I have a mechanical fan, shroud, and a large BeeCool radiator. I tried everything, had dual electric fans, worse heating with those, then i swapped the lower march pulley to a larger diameter, and that helpped a little bit. Well i found this PRW water pump that guarenteed I would have no more issues. Well I am happy. Its has a 160 stat inn it, and with the air temp at 92-95 degrees, and HIGH humidity idleing around town the thing stays pretty darn rock steady at 150-165ish depending on my foot, and the speed. I let it heat soak, and drove it a bit harder, and idled around town some more, it got to 170 once, and came right down and that was when i idled it into the shop, and revved it up a bit just sitting there.

Very happy with the results. the pump has a design that pushes the pump housing back into the timming cover, and the pulley is platted off in design to keep any cavitation from starting.

Heres a linky.

http://www.prwonlinestore.com/1431800.aspx

Kasey

Proof in the pudding that you can't have too much flow through the rad. Nice lookin pump. Wish they had shown a back side view.

Im sorry, I really should have taken a picture of the back side. I may have it on my phone, but its been acting up. Ill look and see.

Kasey

Nope, I cant get the pictures off my card, Piece of crap anyways. Ill do a little mor reserch today and see if I can find some pictures.

Kasey

Kasey, I'm glad you got your overheating problem fixed. I went through the same thing a few years ago with my 340. I ended up with a Flow Kooler pump, pretty much the same as yours but has a steel impeller with a anti cavitation plate on it. I installed the pump on my 408 and even on the hottest days it seldom goes over 180*, most of the time 170-175*.