Technical Hemi crossover for blower application (From idea to production)

I have another thread that is for ideas for hot rod parts.
http://www.jalopyjournal.com/forum/threads/hot-rod-parts-you-would-like-to-see-produced.1041508/
Out of this thread has come many great ideas, one of them from 31Vicky with a hemi. The water crossover for blower applications on hemi engines. The previously available PAW unit is out of production and the set up with AN fittings is hideous and doesn't work with all applications. I have taken it on as a casting project and hope to have another hot rod product to sell through my business, Highway 101 Rod and Custom.

If anyone has contributions to add as to get this done or where the placement of things should be this is the place. If anyone is interested in getting one this is the place. I am going to weld together a prototype and test fit it. Would anyone be interested in a welded steel one? After the prototype is done I will take the dimensions from that and create a casting pattern and have them cast at a local foundry. I also have a local machine shop to do the machine work. I will take pictures along the way of the progress and process for every ones entertainment.

 

Anyone have an opinion on adding a bypass hose provision, for those of us running a BBC water pump conversion?

 

There is a port on the back side of the unit pictured as well as the visible one on the front. You can see it on rear to the to the left of the one on the front.



Monday I'll move my 671 over to my 392 for tall deck block field measurements.

Your 354 will be good for low deck block measurements.

 

That position always struck me as a bit off. Two 90° street elbows, and a very short length of straight hose.

 

For those running the Chevy water pump, is it feasible to have an outlet on the bottom to line up with the water pump outlet? As you are installing the water pump or crossover there would be a rubber hose in between similar to how some Fords do it. On the back side of the original crossover is a boss that is tapped for a small pipe fitting. Does anyone know what this was originally used for?

I stopped by the foundry today to ask how they wanted the gating and sprue to be done. They only want to do two per on the pattern so that makes it easier. I will use my last pattern for the board size and build it accordingly.

 

Here is a good picture of the back side where the boss is on the original one.

 

Typically temp. gauge sender, or alternative path for bypass/cabin heater.

 

Is this a Chevy water pump conversion that is pictured? And if so is that hole in the top where the bypass would come out of it?

 

Yes, and that appears to be a 392. It would be closer on a 354, as the deck is lower.

392:

Here's the ugly on on a 392, just to show how close it is:


Here's a PAW one. Hard to see 'cause it is black, but that's it:

No 354's here, they will be a little closer.

 

How was it dealt with on one with a stock water pump?

 

Like this:

 

That's what I figured. So where lies the problem?

 

Although, the more that I look at pictures, the more I see that people are not bothering with running a bypass hose.

 

Once two street elbows have been installed, it will be very hard to get a hose in there, on a 392, and might be impossible on a 354.

 

I had issues with a 289 Ford with a Snow White water pump kit on it. Without a bypass you can end up with steam pockets that will cause over heating. All I did on that one was to use a 3/8" bypass hose between the heater hoses.

 

Here you can see how mopar moved the water ports in the heads for the 392 down.
And where the water pump bolt holes are. The crank CL to water pump relation remains the same but the 392 is 1/2" taller. The water pump to crossover and BBC water pump relation will be pretty damn the same. You engineer types can stack that up in your sleep.



Here's a 392 with better contrast but it's a different crossover however it is complete engine and you can see why the stuff it where it is and why tatarsammic couldn't use what's currently available.



More of a side profile of the supercharged crossover. The manifold is different and a high rise unit.

 

Here's another shot of a stock unit.
The water pump is 3.5 miles further away from the block than a BBC would be.


If you wanted to incorporate a bypass hose, and it wouldn't hurt,,, you could set it up so the crossover needs to come off to change the hose. Basically a small straight section of hose between the water pump and crossover.

 

I might be on about nothing. I have yet to find a picture of someone actually using a PAW style crossover, BBC pump, and a bypass hose.

Carry on.

 

So the question still remains. Is there room to have a hose nipple on top of the water pump and the bottom of the crossover pointed directly at each other? As long as they don't hit each other a hose can be installed. Is the hole in the water pump pointed directly up? As long as there is about 2" of space and the water pump hole is vertical it could be done.

 

It is straight-up. A hose barb would add about 1-1/4" 'ish.

 

Thanks gimpyshotrods now I just need the total space from the top of the water pump to the bottom of the crossover.

 

Just to clear things up, will the water neck be coming straight up from the middle, or will it be somewhat to the right side, like in the original screenshot?


Sent from my iPhone using The H.A.M.B. mobile app

 

For a blower application, it will need to be out on the far-driver's-side.

 

Yes, it will be as close of a copy of the PAW blower application as I can make it. I might be able to incorporate a bypass into it that will work with the Chevy water pump. I just need someone to measure the distance between the top of the pump and the bottom of the crossover.

 

Maybe this is not exactly correct, but it works on my car 392 with stock crossover.
Top of water pump fitting to heater hose, lower fitting to crossover fitting.
Don't know if this is relevant to the bypass hose situation discussed, but it works for me.
Car runs 180* on a 180* thermostat, and the heater keeps me toasty on chilly nights!
KK

 

So far I've not been able to find one of the PAW units or an owner of one.
Therefore the measurement you seek to that crossover will not be available until the crossover materializes in your hands or on a CAD file. I can get you the distance from the head's water port bolt holes to the BBC water pump on Monday. From that you'll decide the relation of the bottom of the crossover to the water port bolt holes based off of the photos and relative positioning right?

 

Thanks, that works for me. If you can get the crossover bolt to the bypass hole in top of the pump that would be great. Also the distance out from the face of the block and at least one of the head's in relation to the centre of the bypass hole in the pump.

 

My iPad only does so much but kind like this with the grid lines
It won't account for perspective or give me the option to roll fore and aft into the image so some Kentucky windage is needed

 

A friend has a 354 and a 392 both with Chevy water pump conversion so I will measure that in the next couple days.

 

I used the PAW water crossover on my 354 Hemi with a Edelbrock BBC water pump and connected the bypass with a 90 degree brass elbow off the crossover to a 90 degree rubber hose to a straight nipple on the pump.
I run a 180 thermostat and most of the time the gauge reads 170.
You can see the mechanical sender exiting the rear of the crossover.