Number47

doesnt matter what hp you have, the water pump only creates flow, no pressure. pressure comes in when the coolant heats up on a closed system. the rad. cap controls this pressure to about 14-16 psi and opens and dumps pressure/coolant to the puke bottle. so even if the pipe is straight and not rolled it only has to hold 18 psi at the very most

dieselman2300

Sorry, but you are completly wrong on that answer.
This is why on higher HP engines turning 4000 rpms+, we either install electric water pumps, clip the stock water pumps fins and install coolant bypass systems.
Do a search before posting.

Number47

Never heard of such thing till i searched but how many people have engine that produce over 700hp, or turn over 4000rpm??? people with these types of engines are few and very far between

dieselman2300

You better search again 600-700hp is getting to be the norm. Especially the new Common Rails. They can go from stock to 700+ at the flip of a switch.

Personally I am running 568hp to the rear wheels in my 97 12 valve.

I got my twins coming next week hoping to get close to 700 rwhp.

If you are running a 4k GSK, you could pop a freeze plug. It doesnt take much.

johnh

an automotive water pump is not a positive pressure pump, it's a circulation pump with very little pressure, the pressure in a cooling system is caused by heat and expansion

GasganoFJ60

How much did that new heater core cost? I was at a big surplus barn and they had heater cores that looked to be about that size that were $10.

VADSLRAM

It shouldn't be a problem, The hose rubber will absorb to movement. You should easily get 5 to 10 years from somthing like that. I haven't done that particulat mod but whenever I do hose to tube joins I flair the tube end slightly and use double clamps with the screw portion at least 45 degrees seperation. I've never had a leak like that, including redoing several different A/T to radiator cooling lines and on a jeep they flex like crazy.

VADSLRAM

any time you move any fluid you will create both high and low pressure areas. More flow in a given system will create more pressures both positive and negative. I worked on this old Maverick back in the 80s. The girl couldn't figure out why the car would overheat on the highway but cool just fine in NYC traffic. I found by accident that she had a slightly clogged radiator and at higher rpms the water pump was collapsing the lower hose (the light I had clipped to the hose fell off when I revved the engine once).
That said unless you have a highly modified or badly clogged engine you shouldn't ever get more then a couple of psi over your cap rating anywhere in the system, there are too many ways for the water to go after it leaves the pump.

Busboy

This is a great mod, in fact the heater core manufacturers should be building the heater cores with short stubby pipes and we just run the heater hose through the firewall whereby only having one connection.

Lil Dog

Removing the glove box to snug up the clamps (if ever) would be a small price to pay IMHO. I had to tighten my ESPAR clamps once at the heater as its a metric spigot and standard size hose. After that it hasn't been a problem.

And having high pressure on the high HP engines is not the main reason for trimming the blades etc. Its parasitic HP you want to reduce because as said before the pump is not positive displacement and at high rpm the pump will start to cavitate with high wheel speed and drain HP that can be better used at the wheels.

Most frost plug problems are caused by block flex and heat cycling. Having 500 hp is not the reason to have high water pressure. I don't know of too many guys out there driving down the street at 3800 Rpm anyway.

Good write-up!

Number47

but pumps only create flow. a restriction will create the pressure

Mrlou

Nice job, great pictures. Thanks for the info. Made day got done before lunch. Thanks again

dieselman2300

Heres a good read on what happens.
Check out post #43

http://www.competitiondiesel.com/for...t=33430&page=3

rebal

why did your heater core go out so fast?? My 1990 still has its original core. are the second gen cores junk?

cLAYH

Mine had 330,000kms on it but the one in my sister's '01 1500 went at about 120,000kms. So yeah I guess they are junk.