Anyone know the difference (besides stage 2 are made of aluminum) between Stewart Stage 1 and Stage 2 pumps.

The Stewart website just says about stage 2 pumps: "These pumps include several significant performance modifications, compared to Stage 1 pumps, for maximum performance"

But it does not get into detail about what the significant performance modication are.

My 71SS has a freshly rebuilt stock motor and all I want it improved flow for better cooling than the stock water pump. I also plan to go with one of their t-stats. Since, like all of us, I'm on a budget, I would like to go with the stage 1 if for me since it's about 1/2 the price of the stage 2. Thanks!

I believe the only difference is Stage 1 = cast iron & Stage 2 = aluminum.
I've read somewhere that they both contain the same internal parts...but I can't find where I read that at.

Here's the stats from the site. Doesn't look like much of a difference other than cast or aluminum.

Chevrolet Small Block
Long Stage 2 - 23113

* Chevrolet Small Block - Long
* 1969-86 Passenger Cars
* 1973-86 Light Trucks
* 6.932" Length
* 3/4" Bearing
* 5/8" Shaft
* High Flow Pump
* Cast Aluminum Finish
* Clockwise Rotation

The Stage 2 Pumps are the least expensive aluminum pumps and have the following features:

* High flow impeller
* Equal flow to left and right cylinder heads
* High flow and pressure
* 356-T6 heat treated aluminum specially ribbed casting
* Precision ground fan hub with dual bolt pattern
* Zinc-plated rear cover and bolts

Chevrolet Small Block
Long Stage 1 - 13113

* Chevrolet Small Block - Long
* 1969-86 Passenger Cars
* 1973-86 Light Trucks
* 1984-92 Corvette
* 6.932" Length
* 3/4" Bearing
* 5/8" Shaft
* CW Rotation for V-belts
* High Flow Pump

The Stage 1 (Cast Iron) Water Pumps use new original equipment castings, but are machined and assembled by Stewart Components to exacting standards.

* Models with 3/4" ball/roller bearings offer five times the strength of standard bearings
* Precision ground fan hub for perfect pulley alignment High flow impeller
* High flow impeller

Thanks! I did not find that info on the site. Good stuff.

I placed an order with JEGS for the stage 1 w/p and 180 degree t-stat. Unfortunately, the pump is on 2 week backorder. :(

I've always ordered mine straight from Stewart for a few bucks less. Do they not sell direct any more? Also, you might try giving them a call to determine if there are more differences than the ones listed on their site.

^ Ditto - ordered straight from Stewart and it came pretty fast.

Stewart pumps all the way they are the best.
I think the stage one will work for you. I run the stage two the aluminum housing is just higher quality more balanced flow and lighter than the stock housing. If you drill the optional bypass holes in the high flow t-stat you can plug the bypass in the block and do away with that cold spot in the #2 cylinder wall.