Small block to big block conversion?

[Hoppy]

Hey folks I have a couple questions on a 440 swap I'm doing on my 74 crew cab. I bought this truck a few months back out of Arizona with 36,000 miles on it. It came with a sweet running 360 and 727 with a divorced transfer case.

I drove the truck home all the way from Arizona to Michigan with not a lick of problems. I have swapped the 2 barrel out for an Offenhauser 4 barrel intake and an Edelbrock carb. I then bought a set of Hedman ceramic coated headers, headman turbo mufflers, and all new pipe out the back. 10 miles after the exhaust job the trans starts slipping, and the bottom end of the 360 starts knocking. I was very impressed with the turn of events now let me tell ya.

So getting to the point! I happen to have a 75 440 and short shaft 727 I pulled out of a 1976 camper last summer with 32,000 on them. I was able to drive the camper for a bit and know the motor and trans worked perfectly. I believe all I have to do is swap the tail shafts and I will be in business there.

My questions start here (thank you for being patient)

1. I noticed the 3 prong plug in on the trans was different or am I wrong?

2. What is supposed to be plugged in there as there was nothing plugged into the one I just pulled out of the truck?

3. Does anyone have any tips or hints for things to watch out for when installing the 440?

Thank you in advance for any and all help!

[712edf]

Welcome!!!

That 3 prong plug is the NSS (neutral safety switch). Prevents vehicle from cranking in gear & provides ground from reverse lights. There is no voltage present, this is a ground switch.

The truck should NOT crank at all, even in Park/Neutral if the switch is bad or unplugged.

If a vehicle cranks with this unplugged it means someone probably ran a ground wire to a post on the starter relay that must be grounded for it to work.

I believe both the crew cab & the camper will have a short shaft 727, but you already know if they are the same.

Motor mounts & radiator hose routing are 2 things that generally need to be addressed. Also don't know what oil pan would be on a 440 from a camper, but think it needs to be a rear sump for the truck.

Bucky

[pwdave]

the only subsitute for cubic inches is more cubic inches

Hoppy, the rubber isolators from the small block will be the right ones for this trade, same hole even! you will need the steel mounts for a b-rb block that bolt on the side of the block. the power steering mount is probably the right one already.

the pan is rear sump,and the exhaust will be a center dump on both sides unless you go with headers. there may be a slight interference with the heater box on the pass side and it will be tight on the driver side(brake booster).

if you get everything together before you start, it is a pretty straight forward swap. on the side that the bottom hose comes out of on the front of the engine, ma mopar made several different water pump housings that came out on either the right or left side depending on the app.(I have both in the shop). this is a really nice swap and works well.

almost forgot, use the motor home cam, I thought I would be smart and run a small cam for the lope. (crane fireball) believe me when I tell you that a four wheel drive truck with a 3" lift @ 130+mph is scary, I was much happier with the stock cam! good luck with your project, it will be nice. Dave

[Hoppy]

Thanks guys! I really appreciate it! These are the tips I was hoping for. I am going to run headers and duals all the way back. I am not going to open the motor up and change anything internally at this time. It has only 32,000 on it and ran like a champ.
I have another question. Is it possible the camper 727 is lower internal geared than the truck 727 I pulled out? Is there any differences between the two? What I mean by that is is the camper 727 heavier built in any form?

[712edf]

While there may be differences as to number of clutches in different 727's, I believe that most had 2.45 1st gear, 1.45 2nd gear & 2.20 reverse, if not all.

bucky

[Hoppy]

Ok here is an update on the way things are shaping up. After further inspection of the 440 I have decided to put a fresh top end on it. The bottom end checks out real good. I am thinking of putting a set of fresh 906 heads that are flowed, polished, decked, with new springs and valves. New purple 480 cam and lifters. I have a Edelbrock rpm performer intake, polished aluminum valve covers, Flowtech ceramic coated headers, new 7 qt. oil pan, new mini high torque starter, and I am thinking of ordering a new MSD ready to run complete sytem. I am thinking of topping the intake off with a 1407 Edelbrock with manual choke and secondaries. What do you think of the set up? If anyone has does or don't or any opinions on the set up I would appreciate your input.

[pwdave]

Hoppy, everything works except the heads and cam. the heads you are wanting to run, if they have had hardened seats installed are good, if not you need stainless valves. stock valves and stock heads are not compatable with the crappy gas we've got. if you are going to go off road with this truck, the cam you have picked is way too big! an rv cam is an excellant choice for trail. the .480 makes it's power at an rpm level above what is comfortable for trail, the lower the torke band the better, (thats what makes the old flat heads so good in 4x4s) my 440 with the fireball crane was a horrible choice and the cam you have picked is bigger yet. good luck with your truck, Dave.

[Hoppy]

Good stuff Dave thank you! I do plan on driving lots of trail so that is great to know!

[greg rider]

Ask the cam manufacturer about advancing the cam a few degrees. By doing an advance you move the power band lower, a retard will move it up. Ask what 2 degrees will do,it may turn your high rpm breather cam into a low rpm stump grunter. There are degree keys available from Mopar. It's worth a few calls to find out.

[jakenok]

If you are running power brakes, you may find your booster hits your valve cover. there is a BB power booster you might need.

[Hoppy]

OK here is a little glimpse of what I have been up to with the conversion. It has taken longer and you can see why. I was not originally going to go this far with an engine build, BUT I just can't seem to go halfway with anything I do.

[greg rider]

NICE!!! I only see a few issues though,,the oil pan needs to be a rear sump for trucks and the water pump lower neck may or may not be on the correct side. Please don't think I'm being critical I just don't want to see you run into headaches that others (myself included) have delt with. Looks good,,I'm jealous of that engine.

[Hoppy]

Thank you Greg! I do have the same concerns with the oil pan. It is a center sump and I hope my tape measure isn't wrong. The water neck should be OK I have an aluminum 3 core radiator and I pointed it towards the correct side for the new radiator. That oil pan though makes me nervous.

[The Other Ross]

GOT to go with the rear sump pan on a 4x4 due to suspension compression.Did this same swap on a 72 w200 crew years ago(right down to the motor home 440).I left mine bone stock with the exception of a Mopar Perf distributor,Jacobs coil and wires and a Flowcooler water pump.I still had to run 94 octane Sunoco to keep it from pinging at any timing setting.I could get away with 87 in COLD weather but that was it.

[jakenok]

There is an truck oil pan and manifolds and radiator for sale on Ramcharger Central right now. (all parts seem to be able to be purchased seperately)