Building a 77 motorhome 440

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65D100

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Good evening, I own a 1965 d100 on a 77 w100 frame that I intend to swap a built 440 into. I have some engine building experience but would like your opinions. I recently got a 440 and 727 out of a 1977 motorhome with 40,000 miles on it. The block, crank, pistons, etc are super clean. No lip on the bore, cross hatch still clearly visible as well. My intention is to build a motor that I can still drive daily, but has plenty of power. I have been looking into the indy 440-1 top end kit and I think I would like to go with it for my build. I would like to hear what you guys think of the kit, if you think its far more than its worth for something that will see street use only. I would also like to hear what yall would recommend for my build. Everything from gearing, to transmission build as well as the motor build itself.
 
I love the color of your truck. You won't have to go exotic to get 500+ out of a 440. I'd start at the 440 source home page and look at heads.
 
Id like it to be more to the tune of 5-600 hp though 375 is plenty enough for any application
In that case, you'll need a different top end for sure. Indy is one good way to go. 440 Source another. You might try contacting @PROSTOCKTOM here on the forum. He's a Molnar dealer and a fine fella. He may can get you a deal on a top end kit. I don't know. I'd much rather support a member here. I tagged him, so maybe he'll chime in. I know he can fix up on the bottom end.
 
i know that you're shooting for a much more lofty hp goal but years ago i had 440 in my 66 D100 and it was everything i could've hoped for and then some as a daily driver.

i rebuilt a RV 440 with a stock bottom end and some speed pro L2355F forged units. up top i bought the edelbrock performer RPM kit-- heads, cam, intake, timing chain and lifters. i backed it up with a mild 727 that had a shift kit and RV converter in it and some 3.23's

that motor was stone ax reliable, made plenty of power and was about as good on gas as you could probably get with a warmed up 440. it had enough torque to pull down a house and enough HP to bury the speedo as far as you were brave to drive.

the best part was that it had absolutely wonderful street manners.

anyway, to your question at hand, you're gonna be hard pressed to make 1hp per cube with those pistons a million miiles down in the hole and dog water compression-- no matter what heads you've got to put on it.

so adjust your expectations or the opening of your wallet accordingly.
 
i rebuilt a RV 440 with a stock bottom end and some speed pro L2355F forged units. up top i bought the edelbrock performer RPM kit-- heads, cam, intake, timing chain and lifters. i backed it up with a mild 727 that had a shift kit and RV converter in it and some 3.23's
I like it. You definitely need pistons but shouldn't have to buy a stroker kit unless moneys no object. JMO
 
While money is definitely a big factor here, and I completely agree that a basic 440 build would be plenty, frankly I just want to build a stupid powerful motor. I have been looking at 440 source motor kits and I think id like to go with the 650 hp kit. Engine package no. 3. Does anyone have any experience with this kit? I appreciate all the replies by the way, I have tried other forums and havent gotten any good replies.
 
what ever you use, make sure you only use high zinc oil because oil companies have pulled a fast one.
you really need to follow that up
 

I bought the 440 Source 500 kit (balanced) and stealth heads. 10:7 compression. Block bored 30 over on a 1976 440. Car is a beast. Street only 323 gears.
 
While money is definitely a big factor here,
*proceeds to list 10K worth of motor stuff*
frankly I just want to build a stupid powerful motor.
cool. cool. cool, cool, cool. just be ready to open your wallet W-I-D-E

while you're on the right track-- heads are a critical part of the power makin' equation-- that 1500~4K you're dropping for heads is only one aspect of the whole encharito amigo.

big stupid power means big stupid money. unless you have a hook up at a machine shop and race car friends that are gifting you leftovers the cost of getting there is steep and adds up quickly.

also, stupid powerful motors don't make great daily drivers. beyond generally not having the greatest street manners, they require a higher level of care and feeding than something built well that makes reasonable power. but you'll hear otherwise from a bunch of folks, so that's up to you to separate the wheat from the chaff there.
 
While money is definitely a big factor here, and I completely agree that a basic 440 build would be plenty, frankly I just want to build a stupid powerful motor. I have been looking at 440 source motor kits and I think id like to go with the 650 hp kit. Engine package no. 3. Does anyone have any experience with this kit? I appreciate all the replies by the way, I have tried other forums and havent gotten any good replies.
What are your financial expectations? Do you think you're gonna build a 650HP 440 for 5K? Ain't happenin, Paco. That 650HP kit you're talkin about is 9500 bucks.
 
That engine builder [Jim] from Idaho proved you can can make good power with a motor home 440. There is a long thread out there where he did dyno testing. Get a set of heads, spec a camshaft,SD intake, headers and run it.
 
Here's more rub for you. None of those kits come with STD pistons that I see listed, so no matter how much beautiful cross hatch you have, it's gotta be bored. Also, there's no way in HADES I would bolt anyone's heads on without being completely disassembled and checked out and corrected by a competent machine shop. Crappy valve jobs, valve guides too tight or too loose and on and on have been found......the hard way. There's no way I would ever just "bolt dat chit together". That's a LOT of dough to take a chance on like that. I would be having a shop check ALL of it. Crank runout, clearances, indexing, rod lengths, balance on everything. You name it, it would get checked. It's crazy to think someone can't make a mistake when you're talking about thousandths of an inch.
 
That engine builder [Jim] from Idaho proved you can can make good power with a motor home 440. There is a long thread out there where he did dyno testing. Get a set of heads, spec a camshaft,SD intake, headers and run it.
Yeah and low compression too. Jim Laroy.
 
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