Best water pump and housing combo?

[85daytona]

I am finally get around to putting my car back together. It's got a CB motor and I want to have the best stock water pumper combination I can find. I hear the CB pump cavitates but is this the housing or the reverse rotation? If I use a non CB pump housing then what pump do I use? Can I use the newer rubber 1 piece gasket?

Thanks, Chris

[glhs727]

Chris,
glad to see you back on the forum... about time you got back to working on your car! did you graduate?

[85daytona]

Hey Cindy! Yes! I did graduate and it felt so awesome :) but now I'm in grad school haha so still no $$$ yet for that 2.4 conversion :eyebrows:. I'm trying to get the car together before this next semester starts though; gotta look fly for grad school ya know :p. I need to buy some stuff from you when you're available.

Do you know if there is a non common block water pump that has the extra outlet on the bottom for the heater core stuff? I found a post saying the best combo is a non common block housing with a non common block pump with the non common block pulley so it spins the right direction. I think I have a non common block housing but it doesn't have that extra outlet for the heater core stuff. I need to go check out my 85's setup; just not near it at the moment.

Thanks, Chris

[thedon809]

My 86 Daytona had the outlet on the housing and that is what I run on my omni.

[cordes]

you could pretty easily drill and tap the housing to accept an NPT fitting which you could have a hose barb on.

[zin]

This is the first I've heard of this "problem", can someone point me towards some background info?

Mike

[cordes]

I've read this mentioned many times, but I've never had a problem with it personally. I do believe there is much to be gained by porting out the pump housing. I could see where the structure of the housing could induce some cavitation.

[85daytona]

Ok so heres all the info I have dug up on the issue. For pretty much everyone it probably hasn't been an issue but I just don't want to take any chances if it's a fairly simple fix.

http://www.turbo-mopar.com/forums/showthread.php?50323-waterpump-housing-questions.&highlight=rubber+water+pump
http://www.turbo-mopar.com/forums/showthread.php?67236-Which-Water-Pump-should-I-use&highlight=rubber+water+pump
http://www.turbo-mopar.com/forums/showthread.php?31918-Need-info-on-water-pump-housings&highlight=water+pump+housing
http://www.turbo-mopar.com/forums/showthread.php?29795-Water-pump-motor-question&highlight=water+pump+housing
http://www.turbo-mopar.com/forums/showthread.php?28198-88-water-pump-to-89&highlight=water+pump+housing

Verdict so far is: Use old style housing, port it, old pump, old pulley. Or use the new pulley with a longer belt to make it spin the right directions. I've got to go take a look at the belt setup on my 85 Daytona and see how it all will actually go together for the CB motor

Thanks, Chris

[tryingbe]

Here's what cavitation is, http://en.wikipedia.org/wiki/Cavitation


Personally, I haven't seen any cavitation damage on the waterpump or housing on a TD. I'v seen plenty of damage from people not changing their coolant though.

[johnl]

Yep, coolant is sacrificial, it is designed to be so. I try to change it annually.

[thedon809]

I run the hoat Mopar coolant in all my cars.

[Reaper1]

The whole cavitation thing was started by Ed Peters. Has anyone ever PROVEN this? The direction the pump spins will have NO effect on cavitation. It's the impeller and housing design themselves. Another thing to consider is that the coolant system is under pressure.

Cavitation is where the boiling point of the liquid is reduced and the liquid spontaneously boils causing air voids. (Most of the time this is due to either very high velocity, or a sudden decrease in pressure caused by a disruption in flow) Most of our systems are pressurized to 16psi and on top of that have modifiers in them to increase the boiling point even more.

I can very easily understand where the internal shape of the housing WILL cause some cavitation. What I'm not buying is that the direction the pump spins is the cause. The impeller blade angle and how the overall impeller interacts with the flow will determine if that part is causing cavitation, but the direction it spins will really have nothing to do with it.

So, the argument could be made that the impeller design for one pump is better than the other, but I don't think simply the rotational direction is the key.

[cordes]

I thought some folks say there's a difference in how the impellers are shaped or the number of fins or some such? I'm with Tryingbe in that I've never seen any damage from cavitation.

[86Shelby]

I've had no ill effects from porting the housings. Generally having someone build up the area with a tig welder at the sharp turn right before it mounts to the block helps out a bunch when porting the commonblock housings to get a smooth turn with plenty of area right there. The non-cb housings generally have more material around there to port without any welding.

[cordes]

Oh yeah, if you built it up at that point it would flow incredibly well compared to stock I would think.

[4 l-bodies]

IIRC, Peters point was the CB pump was a HP loss. Flowed too much. In the Phoenix tapes he talked about even removing half the blades in the early pump to reduce HP losses as RPM's rose.
To answer your question about early housings, some early non l-body non AC cars (turbo 84-85) used a tee in the lower hose, but I think about everything was changed over by 86 or so. L-bodies use the coolant return nipple in the radiator, so they used a different housing that omitted this fitting. So any 86-88 non l-body should do the trick. To use early pump on CB, you need to either notch the oil pan slightly, or do like Chrysler did and just ball-peen hammer that area so it fits (lol). The CB waterpump uses the 1 piece rubber gasket, not the early pump. Not interchangeable.
BTW- The 16V TC common blocks used the early housing and waterpump. I use the early housing and pumps primarily in my CB L-bodies because the waterpump inlet lines up properly with the lower radiator hose. The CB inlet is clocked quite a few degees forward towards radiator core support. The l-bodies are pretty tight in this area.
Todd

[85daytona]

Ok guys thanks for all the replies. I decided to forget using the old pump housing for now since I don't want to deal with notching and getting the right belt. Instead I just ported the original CB housing a little and cleaned it up. I didn't realize how much smaller the non CB housing was until I set it next to my CB one, it does look kinda wimpy lol. I'm not sure I realy knew what the cavitation problem was. I definitely have not seen any real cavitation damage. I just thought it was more a cooling efficiency deal. Anywho sticking with the ported CB housing for now.

Thanks, Chris