77 motorhome 440 vs 71 360-what to use???

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dusterdan

dusterdan

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Hey guys....so here's some background on what i have, what i'd like to have and i'm all ears for any opinions and comments on the matter:)

I have a 70' duster, factory slant six car and also have 2 engines here, both complete NEVER torn apart.
(1)71' 360 with 727A
(2)77 440 with 727 from a Coachmen motorhome

In the long run, i want my car to handle relatively well (keep up with base model challengers at least) and be comfortable on the highway and have a minimum of 400hp naturally aspirated. Since i'm starting from scratch either way since EVERYTHING in the drive line will have to be replaced, i just wanted some general feedback on what you guys would do??? It just seems so much cheaper to build a big block with good power than a small block with equivalent numbers and now that Procomp has aluminum heads for BB's for $450, i could shed some weight and not break the bank. My budget is about $3500-$4000 for either motor, 727 auto for either, 3.91 gears....keep in mind both are complete. Perhaps somebody can shed light as to some PROS AND CONS OF A MOTORHOME BB AS I KNOW NOTHING ABOUT THEM. Thanks in advance, you guys are great! -Dan
 
dusterdan said:
Hey guys....so here's some background on what i have, what i'd like to have and i'm all ears for any opinions and comments on the matter:)

I have a 70' duster, factory slant six car and also have 2 engines here, both complete NEVER torn apart.
(1)71' 360 with 727A
(2)77 440 with 727 from a Coachmen motorhome

In the long run, i want my car to handle relatively well (keep up with base model challengers at least) and be comfortable on the highway and have a minimum of 400hp naturally aspirated. Since i'm starting from scratch either way since EVERYTHING in the drive line will have to be replaced, i just wanted some general feedback on what you guys would do??? It just seems so much cheaper to build a big block with good power than a small block with equivalent numbers and now that Procomp has aluminum heads for BB's for $450, i could shed some weight and not break the bank. My budget is about $3500-$4000 for either motor, 727 auto for either, 3.91 gears....keep in mind both are complete. Perhaps somebody can shed light as to some PROS AND CONS OF A MOTORHOME BB AS I KNOW NOTHING ABOUT THEM. Thanks in advance, you guys are great! -Dan
Click to expand...

If 400hp is all your after then get the 360, If you want the torque then get the 440, But just keep in mind either one will need the compression brought up "at least" a solid 1.1/2 points, you can make the 440 handle well even with iron heads, The Procomps i'd stay away from, get the steaths, If you play your cards right & shop "smart" along with a good machine shop that won't rip you off you can get the whole engine done for around 3000.00 carb too pan, Start with the block & consintrate on the "shortblock" only for starters, then pick the heads/cam/intake/carb for the intended use. Shoot for a good quench, you can use the factory cranks, there both cast but plenty strong. Heres a few options.

360

NA http://www.summitracing.com/parts/UEM-KB107-030/
N2o something like this: http://www.summitracing.com/parts/PBP-12346-030/

Heads http://www.hughesengines.com/Index/...Q3lsaW5kZXIgSGVhZHMsIEFsdW1pbnVt&partid=10968

http://www.hughesengines.com/Index/...el1=Q3lsaW5kZXIgSGVhZHMsIElyb24=&partid=25741

Cam XE285HL

Now you can opt. for a stroker kit like this one. This would be the kit i would get, its balanced with forged pistons.

http://www.hughesengines.com/Index/...el1=MzYwLzQwOCBTdHJva2VyIEtpdHM=&partid=26468





440

NA http://www.summitracing.com/parts/UEM-KB237-030/
N2o something like this http://www.summitracing.com/parts/PBP-12498-030/

Heads http://store.440source.com/Stealth-Aluminum-Cylinder-Head-COMPLETE-SINGLE-HEAD/productinfo/200-1055/

Cam Hyd. XE285HL
Solid XS282S or MP .557
 
I vote 360, stroke the thing out to 408 and have at it! You'll get a **** load of torque with the stroker and it handle much better then with a 440. Just use 1" torsion bars and good shocks you'll be set. Either way add sub frame connectors (weld in kind, I have the US car toll version) to stiffen up the chassis with the added power. If you plan on driving the car long distance, I'd reccomend that you use the GM 200R4 overdrive tranny which is smaller then the 904/727 (meaning not tranny tunnel surgery!) but like the 904 needs to built up to hold any real power. You can contact cpt transmission for the trannny and order up the adaptor from wilcap. If you follow Mopar To Ya thread, he is going to be installing this same tranny in his car.
 
dust451, thanks for the links! and 70Duster, i currently have 1.04 bars in and they're great (even with the little slant not "beat you up stiff" and i've actually never heard of that trans i will definitely be looking into that and the post. And connectors are definitely first on the list! Does anybody know though what the deal is with motorhome 440's though? Yes it's a smog year motor but there's no cats on the motorhomes, has a big thermoquad with no smog stuff, probably loooow compression (from the factory) but are they any different than a passenger car motor? I believe they have extra water jackets???
 
If you want it to handle good, then leave the 440 alone.
 
OK - IMO, I am assuming you are keeping the short block from both and that IS the starting point. The MH 440 should be steel crank low compression (assumption). On the cheap, you will need a new oil pan set up, heads, intake, cam and ignition. Not a fan of Procomp, but they have the small chamber heads which will increase your compression, MP cam @ about 474 and Craigslist intake with a Napa electronic distributor and MP box from Summit oh and factory PR. Rockers and shafts you can use from the MH, valve covers etc and you will be close to the 400 range. The MH transmission may be an issue, if it has the large brake on the rear, you will need to swap that or get a whole new one. And water pump

As for the 360, not sure what base you are starting at, so you will now better.
 
The main question is whats your budget? The 360 is a relatively simple project with inexpensive(and easy to find) parts into a platform that was meant to use it. Where as the 440 swap consist of harder to find,more expensive parts which are going into a platform that was a handeling compromise at best. All it takes to make a 71 360 run is a good set of pistons that you can zero deck and a decent cam and a set of larger 2.02 valves for your heads.A decent 4 barrel and some cheap headers and you can keep up with most folks. You can use the appropriate 727 trans with either engine.
The 440 motor home motor in 1977 is more than likely a cast crank and the factory pistons are a mile down in the hole because they didnt have any compression.If you just add aluminum heads to reduce weight even with the closed chambers you will need more compression to make it run well.The cheapest headers for this combo are a couple of hundred used and you have to cut your fenderwells to use them.Chassis headers for this combo are $400+ and usually sell for $350 used. When you consider that most 440 stuff new is generally 15-20% higher than small block stuff and used stuff is more difficult to find. You could build a decent small block that would run well and still get fair milage for a fraction of what a decent big block would cost and get terrible milage not to mention how nose heavy a big block A body is.The 727 out of the MH wont work in a car(although you could rob the heavy duty internals out of it) Just my experience,take it for what its worth.
 
I chose the 440 over the 360 myself. The MH 440 block should be no different than a car of that same year. My block is a '76. A 440 with aluminum heads, intake and water pump actually weighs less than a stock 360 so don't listen to the "they dont handle as well" talk. Its all on how you set it up. A 440 will make 400hp easy enough AND give you great torque.

MH 440 pros;
-ITS A 440!!
-Unique
-Makes that 400hp at lower RPMs than that 360 will
-ITS A 440!!

Cons;
-You have to listen to people constantly say its a waste of time...
 
Bmsjax said:
I chose the 440 over the 360 myself. The MH 440 block should be no different than a car of that same year. My block is a '76. A 440 with aluminum heads, intake and water pump actually weighs less than a stock 360 so don't listen to the "they dont handle as well" talk. Its all on how you set it up. A 440 will make 400hp easy enough AND give you great torque.

MH 440 pros;
-ITS A 440!!
-Unique
-Makes that 400hp at lower RPMs than that 360 will
-ITS A 440!!

Cons;
-You have to listen to people constantly say its a waste of time...
Click to expand...
And if you apply the same all aluminum stuff to that 360, that 440 will still out weigh the 360. For the cost to rebuild the 360 vs making it a 408 vs the 440. Your best bet would still be the 408. Tons of torque and horsepower for less cost then to do the 440 up right and buy all the required Big block parts to fit it in the a body. If you look up user ou82 he just built and sent a 408 (or was it a 416?) to NY that was making like 500+ HP and 450+ TQ. Just something to think about.
 
1970Duster said:
And if you apply the same all aluminum stuff to that 360, that 440 will still out weigh the 360. For the cost to rebuild the 360 vs making it a 408 vs the 440. Your best bet would still be the 408. Tons of torque and horsepower for less cost then to do the 440 up right and buy all the required Big block parts to fit it in the a body. If you look up user ou82 he just built and sent a 408 (or was it a 416?) to NY that was making like 500+ HP and 450+ TQ. Just something to think about.
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True, but the question isn't whether a 440 with aluminum parts weights less than a 360 with the same parts, so that's not the point I was trying to make. Just that a 440 shouldn't make handling any worse than a stock 360/340/318 A-body if set up properly.

Now we're starting to talk about different things. I am talking about how a 440 in an A-body wont cost as much or handle as bad as being implied. Not about how someone made a 500+ 408(or 416). Thats not following the question asked in the original post. But FYI, I'm sure I could throw just as much into a 440 stroker and make 600+. If that is what dusterdan wants to know.

So far during my 440 build I have only found the headers to be the only part that has a noticeable price difference vs. its SB counter part and they are quite a bit more. Intake, heads, cams, pistons all seem to be very close in price. I havn't spent more than $20 more for a BB part over the cost of the SB part.
 
dusterdan said:
I believe they have extra water jackets???
Click to expand...

Not extra in the block, '75+ blocks had redesigned water passages that have the ability to cool better than previous. I have heard that MH heads have extra jackets in between the spark plugs to cool the heads better but I have not actually seen proof of this. But anything is possible right?
 
ya'll are great! Bmsjax, we're only about 35mins apart ever been on that website socalcarculture.com? They have a list of shows in our area it's great! I appreciate all the input very much....i've been gathering quite a bit of information on the 360 i have (both motors are complete from intake to pan) and it seems like a decent setup with a performer rpm, 2.02 heads, a nice cam, and a 750 i should be close to 350hp. The thing is though is that it is a "J" head motor, meaning by the time i have valves put in and machine work done, i might as well spend some more to buy the RHS heads. With the MH 440 heads, i don't know the specs but is there any performance in this head (new valves+pistons=power potential?) Thanks again, you guys have been wonderful:mrgreen:
 
dusterdan said:
ya'll are great! Bmsjax, we're only about 35mins apart ever been on that website socalcarculture.com? They have a list of shows in our area it's great! I appreciate all the input very much....i've been gathering quite a bit of information on the 360 i have (both motors are complete from intake to pan) and it seems like a decent setup with a performer rpm, 2.02 heads, a nice cam, and a 750 i should be close to 350hp. The thing is though is that it is a "J" head motor, meaning by the time i have valves put in and machine work done, i might as well spend some more to buy the RHS heads. With the MH 440 heads, i don't know the specs but is there any performance in this head (new valves+pistons=power potential?) Thanks again, you guys have been wonderful:mrgreen:
Click to expand...
I've been to that site now :D hahaha. Ya, I grew up in the Fullerton area, I'm only down here for work. So if you want some help anytime let me know.
MH heads flow decent enough. Before aftermarket heads came around the 452's were the ones to have. But here's some flow comparisons(intake);
------Edelbrock E-street heads ------Stock 440 452 heads
.100 -------------- 79 ---------------------64
.200 ------------- 143 ---------------------131
.300 --------------207 ---------------------169
.400 --------------256 ---------------------187
.500 --------------278 ----------------------203

So aftermarket is, of course, better.

Stock heads, stock MH compression(9:1), performer intake, performance cam, headers and a 700cfm 4bbl carb and you should be looking at 370-380 HP. So for $1000 your already only 20HP from your goal. Have a little work done to those heads and they'll probably flow real close to the eddy's. $300 for pistons w/10.5:1 compression and your lookin at 420-430HP.

With the 360 spec you listed your lookin at 380-390HP. Thats with intake, cam, headers, 750 carb and j-heads that have been worked real good. Don't know the price on all that... $1400? Less if you know the right people.

It all looks pretty close in cost to hit 400HP with either. The difference is the BB will make that 400HP 1000rpm lower with 100lbs more torque than the SB.

I chose the 440 over the 360 cause a BB will always make more power than a SB, the 440 A-body is unique, 'who wants to see another 360 Duster?' was my thought. And I like a challenge...
 
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