Water pump rebuilds

[dirttrackrocker]

I have a stage 3 Stewart WP. It's starting to leak out the vent hole. Does anyone know who might rebuild them? I e-mailed Stewart and got no response..

[dynoman14]

I have been fixing them for about 20 years. I carry the bearings one seals but do not guarantee the housing against cracks when pressing the pump bearing in and out. That pump has been made for more than 20 years and has a wide range of casting quality some real good some not so good. I did 3 for $500 last month and all 3 were fine. Customer had a lot of special work on the pumps so he wanted them fixed.

Bearing is unique and pretty expensive.

Might be cheaper to find some rebuilt or good used.

I can sell you an Adams and trade in your Stewart just pm me.

[cvra]

Ok maybe I'm misunderstanding, but, they're couple hundred bucks new on sw website
http://www.stewartcomponents.net/Mer...y_Code=ChevyS3
sooo why would you want to rebuild, and "dynoman" hey why would anyone want you or anyone for that matter to do them at $167 a pop with no gaurantee when you could get new for $23 more...guaranteed???

[dynoman14]

99% of the pumps I rebuild have the original cost @ $500+ and come from folks that don't want to give up the 10-20hp difference they contribute to the engine program.

If you ever get a chance to look at a bearing set or billet impeller you will know why there is such a big difference between a new $167 pump and a real racing water pump.

Kinda like an MSD distributor, you can buy one from Jegs for $179 but a proper build race MSD costs 2-3 times that amount. Take a stock one to a distributor machine and check it out for yourself. If you can't do that just look at the timing light flutter you get at 6000rpms. That is the timing jumping around from cylinder to cylinder.

[dynoman14]

As far as my hundreds of 4m customers, I dyno'd 11 carburetors for FREE since the first of the year. Nine of them, customers did not want touched and all nine of them were below the 403hp that a stock Holley 650HP makes on my Superflow ChasssDYno. All nine of them were aftermarket built race carbs. The other 2 were sent out at 417 and 421, both picking up 15+RWHP over the initial runs.

Water Pumps,
Howard is a close friend of mine and I have been using his stuff for 25+ years, and used to pick up my pumps at his house in High Point so I am pretty familiar with his products.

Like I said, the pumps I work on are ( $500+ ) mostly from vintage road race cars where customers want to keep the parts as they were when the engines were originally built. The twin bearing set I use and the double pitch billet impellers I use are not common to the stock pump. They are similar to the bearings and vane pitches used in the newer style turbos so the flow rates and drag changes as pump speed increases.

SCD,
I am happy that your Adams pumps are as good as your Stewarts all that means is you don't know how to make the ADAMS better than a Stewart or your measurement system is not accurate enough for A-B-A testing to do so.

As you already seem to know everything there is to know about racing this will be for the folks that might want to learn something...

To accurately measure the HP losses of a water pump I re-designed and adapted a 50hp Kart engine dyno to properly evaluate what a water pump actually does and how much water it moves. It is very important to know how much water is moving and the drop in water volume as the head pressure at the water pump increases. As the system pressure increases, so does the boiling point of the water so 35# systems are almost twice as efficient at heat removal as 18# systems. I guess you already know how much HP this can save / make and why some follks can run an electric fan on a dirt car and some can't.

Anyway, low impeller drag on crate or super engine at 6500rpms can account for up to 25+RWHP. Once you get to the 8500 range it can be as much as +50HP and if you add in the drag of the fan it can be even more.

SCD,
Since you are so smart, how much rear wheel HP can you pick up running a 35psi water system -vs- a 18# system ???


BTW, I like my "little hole"...

[ford396]

Dynoman,

Would this impeller be similar to the ones that Stewart is using on their Pro series pump. I know they are cnc milled and replaceable. I had talked with Stewart rep about it and he said it was an extremely low drag pump and took little power to run at 4000rpm pump speed.