55-59 reverse cool meets 6x heads!
 

Thought I would share some info and pics how it was originally intended and how to make it work on something like 6x heads on a 59 block.

Pontiac originally used a reverse cool scheme in 55-59. They pumped water from the radiator outlet thru the pump and directly to the cylinder heads. The early heads had provision for "sprinkler" tubes that drizzled water over the exhaust side of the head(internally). The tubes also acted as flow directors to move water to the back of the heads. Some water flowed down into the block but majority flowed from rear of head at the end of and outside of sprinkler tube and entered the manifold crossover then on to the radiator.
The thermostat bypass was NOT at the crossover! The 55-59 timing cover is blocked at the large water holes of the block face. The 59 block and pump in these pics shows the 2 "extra" small holes below the large block face water holes. These holes served as the thermostat bypass AND provided some flow current so the water in the block wouldnt stagnate. A very effective cooling scheme but cost to manufacture plus extra service parts led Pontiac to the more conventional cooling scheme used from 1960 on. Not as effective but effective enough for production/warrantee purposes.

Now here comes the part about how to utilize the reverse cool scheme without heads that can accomodate sprinkler tubes.

Surprise my 6x heads have bolt holes near the front head freeze plugs. The original hoses and water necks bolt right up! Of course that was too easy! You will see in my pics the freeze plug hole is slightly offset to the water neck holes. 2 minor issues 1) slight restriction, 2) probably leak.
One of my pictures I drew a yellow line around the waterneck/freeze-plug to illustrate the issue.

I have space to move the waternecks forward of the heads thanks to the hoses so I will be making a spacer plate to seal from leakage and offset the bore so I wont restrict flow.

See "template" pic.

Next issue. Without a sprinkler(distribution) tube water would want to take a BIG shortcut at the manifold water crossover. Solution, block crossover holes in head with freeze plugs! At the rear of the head I will have to plumb lines and bring the water back to the crossover. I'm going to use the rear freeze-plug/heater nipple location on rear manifold face of heads probably a pair of #10 lines and fit them to the manifold crossover.

Water will flow across the heads front to rear then back to crossover(via return hoses) and some water will be flowing into the block from the heads just as the original 55-59 did. My modern intake will need the bypass hole plugged.

I've got plenty of pictures and the titles should help explain. Also markings on the pictures should help as well.

more pics
 

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More pics
 

I think this covers everything.

Nice work Bruce, this should inspire a lot of the Pontiac faithful.

Bart

a few more
 

Pictures

yellow shows problem area


Hose on crossover as shown is way too small just doin a visual aid here.
Because 6x heads have a place on the heads themselves, I dont have to have temp gauge mounted on crossover. Existing crossover holes will be enlarged to accomodate the size return lines I use.

I think this is going to work out just fine. I'm liking the look of the early pump system and it SHOULD cool well.

Cooling the heads first should be a plus for my planned use of turbos on this build. Planning ported heads 406 cube twin turbo. However, due to current forged crank availability(Ohio 3.75 forging out of stock everywhere I look) I may end up with a 433 4" stroke motor instead. This is a 59 block already at 4.12 bore with room to go to 4.25" safely. Plenty of foundation and reinforcement not found in newer production blocks. My current 4.12 bore may clean up at 4.125" . (4 yrs storage in a damp woodshed in upstate ny got thru my oil coating not to mention mice had moved in with pine needles and bits of rags the block looks worse than it likely is. You could have reassembled and ran the motor 4 years ago. It had been "built" in 62 and never run. Came as an extra motor I almost didnt take home with the car I bought)


I'm NOT going to use the early shorter snout armasteel factory crank, balancer or pulleys so I'll be customizing timing pointer, modern crank seal update to timing cover and address any issues there when I get to it.

Thanks! I've had this worked out in my head quite a few years. Probably 2002 when I bolted a 59 cover to a 400 with 4x heads when I saw the waternecks would bolt up. Didnt do anything with it though. I like that early look AND engineering.

Had plenty of time to think this through though! Movin to Tn in 2006, then the cancer battle (I won) I was starting to wonder if my 59 block would disappear before I finally got a chance to retrieve it. The week before I had planned originally in 2006 to get the last load to complete our move, was when my back fractured and bone cancer was found to be the cause! (I'm mostly better now btw cancer gone 3 yrs now)

I'll wander a bit further off topic here. Still have to drag a trailer up to NY and retrieve all kinds of extra sheetmetal for Debs 69 bird plus a 69 400 and a 73 455, a turbo 400, some 4x heads, and boxes of misc engine stash, another engine stand or two, and another engine hoist and a 8 ton chainfall.

Back in April we went for a family visit to NY and stuffed what we could in our Escalade. Pontiacs are one of Debs high priorities too! We have a collapsed shed(ice build up did it in) sitting on top of some of our stuff. There was still deep snow in the yard up there to easy to get stuck with a trailer down the hill by the sheds. (so we didnt drag a trailer up this trip)

The original ported 1960 "109"(iirc) heads and 59 timing cover that were on that 59 block are in Georgia and may end up on a turbo 301 block if a certain tech contributor for HPP would take time away from his 4 cylinder turbo stuff. (Jeff! call me !)

And finally these Pontiac boards kept me goin thru some rough times and I appreciate them and all who have contributed to my knowledge, kept me sane, encouraged me thru my battle, and gave me lots of reason to move on with my Pontiac addiction. I'm glad you all put up with me!

I'm hanging out in a fab shop building Rat rods/Hotrods and a few "other brand" motors lately! Life is going on and its mostly good!

Bringing this back up again...Bruce, did you assemble this motor? Did the cooling system work out alright? I'm doing the same build using a 57 block [out to 370 cu in] with a pair of late #46 heads. I'd be very interested in knowing the results.
Rocky

I'll be watching this for sure. Was thinking of doing something similar on mine (#48 heads)

Previous health issues had put this on the back burner. Now slow cash flow is slowing me. I should have the car/engine project complete by spring.

During my "health crisis" I did have plenty of time to think this thru. The biggest thing is preventing a water shortcut between the inlet at the face of the head and the water crossover. Simple freeze plugs there resolve that issue. Water has to flow across the head to the rear "exit", which wiil be hoses located where the heater nipple and rear freeze plug usually go. The hoses will get plumbed forward to the crossover so water can get to the upper radiator inlet. I will tap the existing holes for a pipe fitting (likely either 3/4" or 1" pipe id, I dont want restriction there). I may not tap into the actual crossover because there is an aftermarket part for SBC's (that fits under thermostat housing) available already made with provisions for water lines.(Moroso I think)

Water in block will still behave as it did in 55-59. (see timing cover pics) I see no reason it shouldnt work better than the 1960-up cooling scheme.

Where did you get that water pump...with both ends having big end radiator hose connections. Never seen one like that. How dose it work with the after market pumps that bolt to the timing cover.

Thats not the water pump your looking at, it a 55-59 style timing cover. It uses the 4 bolt water pump.

Thanks...wasn't sure.

As Bill said 55-59. Mine had Chrome water necks. That one came off a well built 59 389(+.060) that was built in 1962 and never run! Car it came with(59 Cat coupe) had a numbers matching AN block and tripower in it. The "built" motor was sitting next to it in the dirt! (I almost didnt take it but seller insisted, it sat in a corner of my barn a few months before I got curious why the ports were so well taped. What a surprise,early SD rods JE pistons E-2 cam long branch ex manifolds, Harvey aluminum flywheel. Had a set of ported 1960 heads on it, 109's iirc, a friend in Georgia has them and a spare 58 timing cover/pump assy.) No power option car but did have AM radio and factory rear speaker, Old SW SD tach(it still worked when I tested it). Had a Hurst 3 spd shifter laying on the floor(stub on column) a 55 3 speed gear box in trunk . A scatter sheild made from plate was welded to the frame over the bell area. Car had sat in a field from 1964-2000. 31k miles showing. Original owner/builder had died in an accident sometime in 62. Sadly the floor was rotted away and whoever did the custom tuck and roll interior had cut the piping off the original (nice condition) upholstery! The stainless was still near perfect and chrome was decent. I sold the car in 2004 when I moved. Someone in Ohio bought it. Finally got the block down here in April.

I'd have to make my own electric pump.(doable) This one still feels like a new pump(once I cleaned out the mouse hotel)firm and smooth, so time will tell if its still good.

Pic shows chrome water neck bolted to 6x head(near identical to 55-59 location). Hose is in very good condition(48-51 yrs young) but I'll put new on at final assy. Timing cover will get opened up to accept modern crank seal. Currently fabbing an adapter plate to mount a t400 and 61-63 starter(will use an IHI mini starter from Ames). Initially in some aluminum plate I have(rather soft to actually use but easy to work with and correct mistakes/issues) then final version will be steel.

Pretty neat...was just wondering how we could make the 70's timing cover work.

Id block it off and use a remote water pump instead. Maybe dig up an old "Moon" timing cover that has no water pump provision for a nice nostalgia look. (secondary reason I'm using the early cover/pump) Spotts has the Moon cover http://www.spottsperformance.com/timingcovers.htm I dont know offhand who might have remote pumps but they are out there.

Water doesnt neccessarily need to "flow" thru the block just into it. Convection(hot rises-cool sinks), vibration and current of water moving in heads will keep the block water at safe temp. The water needs to flow in the heads and can just "fall" into the block.

Has anyone ever mapped the temps thruout the heads with one of these set-ups?

PHILLYGOAT

Bruce,
Possibly something else to add to your conversion- the "early" (I'm thinking 61-64ish) 421's had an extra cooling hole between the siamesed center ports. This might help w/ the cooling/distribution. This hole is located on the head gasket, just not drilled on a late model heads.
I look forward to seeing this furthered. I ALWAYS let the SBC boys know who invented a V8 w/ reverse flow cooling... in 1955, not 1993!!

I kick myself for not grabbing all the pre-60 parts off of several (5 or more) 389's that were in a wrecking yard in Fresno. I figured it'd be around forever, but the EPA and city, yada yada yada got 'em closed. Everything was crushed. Bummer.

Now I have a question:
The water comes in through the lower passenger side timing cover inlet, some is fed into the block through the smaller "open" holes from the timing cover, the rest of the water goes into the front of the cylinder heads, through the heads (some is fed into the block through small holes in the deck), then back to the intake crossover via the rear "heater hose nipple" (or whatever is being used), right?
If so, how does the water in the block get circulated/returned for cooling?

I reread your initial post, and it seems like the water pressure coming in would be greater than that of the water coming out of the small holes in the block, causing a backflow, which would be deadheaded inside the block. Also, if the t-stat is closed, how does bypassed water get moved around- again, it seems like the inlet pressure would be too great, but I'm probably just not getting something.

http://www.pontiacsafari.com/EngineCooling/index.htm This will describe in detail the differences between the 55-59 rev cool and the 60-up . Some good pis and drawings too.

Hope this helps

Thanks for the link.
Now I know why several of the cooling holes were never drilled on my 400/455 motors.
I hope you are very successful w/ this.