Dan's Hemi swap project

[wayfarer]

Hey Dan, good to hear that you are driving more and fussing less...hope that you get the little bugs worked out!

Gary

[Dan Babb]

Got an alignment this morning. The toe was off by quite a bit. All straight now and feels a bit better on the road.

Next is to solve the cooling issue (will get hot at stop lights). I made up a small shroud (but it only covers the top half of the radiator). It's just not enough to help. With the radiator and fan I have, I can't make a shroud that will fit the whole radiator.

So I'm going to order a 16" pusher fan for the front and see if that does the trick. I'm not running the heater right now and figure that there can't be a huge difference between a low-draw electric fan and the fan on the heater.

If this works out, then I can try to figure out how to wire things up so that when I drive the truck in the winter and the electric fan turns on, the heater will turn off. There's got to be a way to run relays to make that happen...right?

[buds truck]

Dan, how much room do you have between your pulley and the radiator? I have the same radiator as you (I ordered the exact same one as I recall) and had a shroud built with a spall fan included. It is 3 inches deep with the fan. Do you have that much room?

[Dan Babb]

No...I have just about 2". I tried to find a shroud/fan combo that I could fit on the engine side, but nothing is thin enough to work.

I could probably gain a bit of space by changing to the big block chevy water pump by using adapters that hotheads sells...but then it means a new pulley setup and timing cover (and figuring out how to move the generator so it will line up). To much of a snowball effect to deal with.

I found a 16" Be Cool pusher fan that blows 1300 CFM @ 7.5 amps. I have no idea what the fan I have on there now is pulling through...but it's the 4 blade 17" fan that was on the straight 6 I pulled from the truck. I can't imagine it's anywhere close to 750cfm.

If the electric fan works, then I'd take the pulley mounted fan off and free up a few ponies.

[fstfish66]

they make an electric puller fan with a built in shroud,,, its shallow not to deep,,, for the street rod world,,it turns on either automatically or with a switch your choice,,it may fit your needs,,,search speed way,, jegs,,summit,,,or any street rod vendor,,,

[Dan Babb]

I've seen and searched high & low for a low profile setup that I can fit on the engine side, but I really don't have much room. Really close to 2" is all I have.

Even if I found something where I mounted it so the center of the fan wasn't centered right over the water pump pulley, I just don't see having enough space to make one fit.

I'll try to measure everything again and post up some pics. Maybe a second set of eyes (or a few hundred sets) can come up with something better than a pusher on the front.

[buds truck]

this may be a dumb question, but can you move the radiator forward a couple of inches? It would give you the space you need for the shroud.

[Dan Babb]

It's not a dumb question....but not one that I really want to think about.

The short answer is "yes". I do have some room in front of the radiator to do it. But, then I'm taking the front end off the truck yet again and would rather not have to do that.

The thought of having the front end of the truck in pieces again just doesn't appeal to me. I'm a slow worker and it would be another 2 month project.

[DJ194950]

May i suggest using a flex fan. 6 blades 15" dia up to 18" are avail. about $60 at summit if i remember right. May need a spacer for the fan blades to clear pulleys and such. You only need a minimum 1/2 " clearance between fan and radiator. Use the thinnest spacer as required to clear rear side.

The stock fan on my 50 4dr. only has about 3/4 in. clearance fan to rad., works fine.

If you still feel that a shroud is needed, get apiece of cardboard cut to fit the backside of radiator and tape in place. On the cardboard mark the center of fan on it and remove. Draw a circle that is 1" larger overall than fan dia. (1/2" clearance arround all sides). Cut out the hole and position it in a position that the fan is half in and half out. Best position from what i've read many times and has worked well for me. Try to tape it in that position and make from card board top,sides and bottom pieces to fill the side gaps then add more pieces to simulate mounting tabs . Tape pieces all together and remove, fan may have to be removed to get it out in one piece. Now that houdini has accomplished that, take to a sheet metal shop and have one made from 18 or 20 gage.

Ran out of room on this post to answer Q. about turning heat fan off when electric fan comes on. Can be easily done with 2 relays. If you go that direction, PM me and i'll draw a diagram for you if needed.

Doug

[catfishcuz]

Dan what do you think

[Dan Babb]

Looks like it would flow a lot more air than the one I have.

If you measure from the pulley mounting surface to the tips of the blades on the back side...how deep do those blades sit behind the mounting surface?

[catfishcuz]

Dan it looks like 3/4 of an inch. Butch

[DJ194950]

A fixed blade fan is noisy at higher rpms as most flat motor owners know. Even the 4 blade makes many dislike the sound at 2500 rpm + , really mostly not used to it on our other cars don't make this noise as manufactors started using clutch fans or other fan types with the change to higher reving motors.

I have heard from others that a fixed blade 6 blade fan is even worse than the four with most changing back to the four or using flex fans or electrics.

Still suggest a shroud first, flex 6 blade (if space permits) second, electric (most work, per your statements) last.

Best of luck keeping that beautiful hemi cool!

Doug

[albolton]

Dan, I have the same room problen as you, I found a belt drive electric, but it was over 500 bucks,

I fanally installed a pusher, and it works great, my engine is pretty stout, and it runs 180 all day, without sapping horsepower, lots of guys will tell you not to push with an electric fan, but I have had no problems at all

[Dan Babb]

Thank you for that feedback.

I'm giving a mechanical fan one more shot. A very generous member had a 17" fan that seems like it should fit. If that works out, then problem solved.

If that doesn't work, then I'm going to put a low draw electric pusher fan on the truck.

[Dan Babb]

I gave up on the mechanical fan...even with the 6 blade one, it wasn't pulling enough air to stay cool. I wound up getting a Flex-A-Lite 16 pusher fan that pulls around 11 amps and installed it.

With the truck moving along the road, then temp stays around 195. I have the fan set to come on at around 200 and it seems to be working. The fan will turn on and keeps the temps in check. Then when moving again, it settles back into the 195 range.

The generator seems to be able to keep up with the power demands too. The volt meter reads 13 when it's running.

Because the fan is in front of the radiator, it blends in nicely and you can't really tell that it's on there...so it doesn't spoil the "cool old truck" look.

I also got the rear seat out and put some sound deadening material (peel & seal) under the front seat and along the rear wall behind the seat. I already had the floor in front of the seat done and was surprised at the difference. Sometime over the winter, I plan on trimming out the rear wall and headliner.

[fstfish66]

sounds like the peel and seal works,,,,where di you get it from

[buds truck]

Peel and seal can be found at Home Depot. I got the small rolls, but apparently it comes in larger sizes too

[Dan Babb]

You'll find it in the roofing section. It's similar to the original dynamat material.

[fstfish66]

aah ok makes sense now,,,i couldnt remember where i heard peel and seel,,, a friend used it in a garage we made out of metal rooofing material,,,to seal up the roof to side wall,,some has fallen off in less then a year,,, thanks for jogging my memory,,

[albolton]

I had to really set the fan to come on early, because my sensor was in the bottom of the rad, after it had already cooled, if I set at 180 it was still running too hot, I put a 160 degree stat in and tinkered with the settings on the fan controller a bit, to achieve the 180, really works well, I just realized how bad my spelling is in my previous reply

I'm on an IPad, and it likes to complete words for you, weather they make any sense or not

[wayfarer]

...I just realized how bad my spelling is in my previous reply

I'm on an IPad, and it likes to complete words for you, weather they make any sense or not

...God help the current kids and future generations.....

[bach4660]

Hey Dan you will like this one, I mounted the brake booster under the cab (I will admit I have followed your thread and borrowed a few ideas) anyways, I finally decided on a floor shifter and bought the Lokar shifter kit. Got it and the mounting point is absolutely exactly dead center behind the brake booster.

I remember a comment in Classic truck magazine about slamming your hand in the truck door before beginning a project, and it felt just like that. After some cutting, welding, cursing, I have a shifter.

Lucky I am doing this for fun.

[Dan Babb]

I had more than one ocassion where I wanted to douse the truck in gas and start a bonfire.

[JBNeal]

yep, them frustrating ol' rebuilt Dodges...holey moley