I just remembered another thing I have noticed about the blocks.  The two holes in the front of the block that receive the water from the timing cover always have casting flash in them, some a little, some a lot.  The holes are not machined, I think someone took a punch and knocked the cast iron out of the hole.  I always take a grinder and open those holes out to the core size, which is about 1 inch diameter.  Since some folks have heating problems and some don't, maybe this is a factor.  JMHO.

John in Selma, IN

John - "The Hoosier Hurricane"

It looks to me like the added blades will do nothing but stir water.  The water enters the pump in the center of the impeller, which flings it to the OD of the impeller.  The added blades cannot draw enough water through the 3 small holes to do any good.  I wouldn't be surprised if the original imipeller drew water through the small holes and stole the water from the added blades.  Looks like more stake oil to me.

John in Selma, IN

John - "The Hoosier Hurricane"

This picture is the one he's talking about - crude blades on a disc and riveted onto the original impeller.

You have to have a one inch T-bird spacer under the pump to have enough room to swing this sort of blade in there.

With a smaller pulley - I'd expect this sort of impeller arrangement to really put out some serious flow.  You'd better have a serious sort of poppet hole in your thermostat - and some decent radiator hose clamps.

 
 Steve Metzger       Tucson, Arizona

Dunno, never saw that one. What's it supposed to do?

Frank/Rebop

Bristol, In ( by Elkhart) 

ok so heres another question. that modified water pump, is it hard to do that????? looks like a plate with three vanes  attached to it(welded maybe) and then its bolted to the impeller. that bout right or am i way off. will it work on my truck 292? can never have to much cooling in a truck that works ya know.

hey frank

you stick to your guns with the foundry you know what works they should just make them i used to love it when the holden guys would come in  water thumping away telling me they put in a new thermostat cause the old one was stuck & it was still doing it i used to tell them the engine was shot i was so cruel but thats what happens when you own a g.m.

on the global warming front in geelong tomorrow (thurs) & friday temps will be 38 & 39 dont think im doing to much detailing so much for it being autumn.

moz. geelong victoria australia.

graduate 1980, bus, truck, car, hot rod, boat, submarine, hovercraft, hydrafoil, firetruck, mobile home, jet, helicopter, cruise ship, motorcycle, bicycle, santa's sleigh, clock, alloy bullbar, alloy fuel tank, lens, dr who's tardis, matter - anti matter warp drive buffer & y-block lover

I forgot - mine does have the 6 blade fan too. Definitely more air flow at idle than the original three blade.

Pete - what does your timing light show at idle? Are you using manifold vacuum or ported?

 
 Steve Metzger       Tucson, Arizona

I guess I am the only guy who has the baffle plate on his T Bird. I replaced the fan with a six blade, new waterpump and added the baffle over ten years ago along with an 180 degree thermostat and a full radiator shroud. After that, no more overheating, period. It could have been just a bad pump but it was a very simple install as I was already there.

I agree with John the dumb baffles are probably still around due to "shelf inertia" - and none of the outifts wants to be left holding the last known supply of them.

The T-Bird fan shroud doesn't cover the whole rad surface but it does conform to one principle I know of - the fan tips fit pretty closely to the circular opening. It is a big deal for fan efficiency to block the air that gets flung off radially when the blade tip is "open". The closer the fit of the tip to the shroud the more efficient the blades are at moving air out of the housing.

I recently reassembled the top end of my outfit and held a little "hot idle burn-down" test last night while watching with infared temp probe. I've got one of the Stewart style 1-1/2 inch opening 160° thermostats in there and the rest is stock - standard bird pulley and pump (for now). The quickest way to drive the temp up - and I mean immediately the probe shows a change - is to move the distributor vacuum source to the "ported" opening (retards to the initial advance setting of 10°-12°). Move it back to manifold vacuum and the temp starts dropping immediately - it sits there with 20" Hg and the water outlet checked 175°-177° with inlet air in front of the rad at 85°/90°. With the ported vacuum source the vacuum went to 16" and water temp went over 185°-190° right away. The driver side exhaust manifold had a big change too - that you would expect with retarding the timing. Full vacuum source - 400°F - ported - 550° - it makes me think that retarded timing is a big issue for a lot of the heating troubles I hear about. There seems to be "double whammy" - because the underhood air temp gets a big jump from the exhaust heating.

 
 Steve Metzger       Tucson, Arizona

Re the aftermarket T-bird fiberglass shroud:



I have one, but took it out since the VAST majority of my driving is at highway speed.

I think it may actually limit maximum airflow through the radiator, and when the motor is pushed hard on long, high speed interstate trips, it likely runs hotter. If I moved to the city and had to spent a lot of time idling in traffic, I would consider reinstalling it since it allows the fan to pull more air. (If someone wants to try one, I would sell mine).

6 VOLTS/POS. GRD. NW INDIANA