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Building a smogger 440

Posted By: General Lee

Building a smogger 440 - 05/05/22 09:18 PM

Hey y'all

This is my first post. Have snooped around here just reading around, seems like a good place for my stupid questions lol. So im building a motor. Ill throw all the info i can think of in here first. I was thinking of a 9+ compression motor. Its a 77 440-8 block, will be bored 30 over.
Its for in a 1991 d150 longbox. 3.55 suregrip. 727 auto. It has to run on pump gas, and be a very fun truck. No drag truck, will see the strip a few times a year just for the fun of it. Looking for low end power and torque mostly. So ive done a lot of thinking and research,and here what im thinking.
Summit 6400 cam
Holley 750 carb
Stock cast crank and rods
Stock 452 heads (hardened seats for pump gas)
Double roller timing chain
Melling oil pump
Stock torque converter
Fully rebuilt 9.25, 3.55s solid spacer
Eddy performer intake (or my stock one but you guys will probably change my mind on that)
Cant think of anything else right now.
So my question, what pistons do i get with that and will the setup im thinking work together nicely for a fun fast daily (not really daily bu you get the point) driver.
Thanks a ton, and please dont confuse me with 100 thousand different ideas lol but thanks for all input in advance
Posted By: IMGTX

Re: Building a smogger 440 - 05/05/22 09:35 PM

Hypereutectic pistons are a good choice for cost and durability. I would suggest a decent brand like speed pro but others will have good advice.

I am not sure you are going to get a 9+ compression to run on regular. Around here the regular gas is pretty crappy. Mid grade possibly. Premium yes.

A 440 is a torque monster but the internals are slow to accelerate. Take advantage of that, a Lower rear gear and an overdrive will let it rev faster and still end up the same cruising RPM.

My twocents

Others will have good advice too.
Posted By: Cab_Burge

Re: Building a smogger 440 - 05/05/22 10:54 PM

The Eddy RPM intake is a very good one, up
Way better than the stock cast iron AVS or Thermoguad intakes are twocents
What is the list number on your carb?
Posted By: mgoblue9798

Re: Building a smogger 440 - 05/05/22 11:50 PM

My two cents.

One, does your engine need an overbore? If not then just run the low comp pistons you have. It is tough to run a 9 to 1 440 with open chamber heads and no quench on anything but 93 or higher octane.


With the summit cam you chose, I would just run the stock intake. No reason to spend money on a performer or perf rpm with your combo in a truck that likely will not see north of 5500 rpm.

Now about that cam. If you follow the above and are not spending a bunch on pistons, overbore, and intake, spend a little extra and get a modern cam designed specifically for your combo. It will cost a little more, but will make the biggest bang for the buck. Mike Jones would be a good guy to talk to about the cam selection.
Posted By: Sniper

Re: Building a smogger 440 - 05/05/22 11:58 PM

I would add that a 750 carb, for what you say yo want, is probably too much carb.

It is my opinion that when you are building a street car and you are deciding between two cams, or two carbs, pick the milder of the two.

As for your cam choice, it is real hard to beat the factory cam for what you want. By factory I don't mean the smogger cam, but the muscle car era 375 hp cam. Make sure to degree it too.
Posted By: forphorty

Re: Building a smogger 440 - 05/06/22 12:33 AM

How much does a 91 d150 longbox weigh?
Posted By: Uberpube

Re: Building a smogger 440 - 05/06/22 01:15 AM

Sounds just like my first 440. Don't bother with anything less than the l2355 piston. I bought the l2266f and they were way down in the hole like stockers I ended up decking the block square then milling .050 off the 452 heads with steel shim gasket. I have had the 6400 and 6401 cam in that engine, it's a dog with the 6401 down low, but picks up later. I run the motor on 87 octane all the time, I just couldn't go too crazy with advance curve, it likes the middle weight springs and I took the plugs colder because it use to run on with the key off.
With the amount of head choices out there now, I don't think I would ever bother with stock heads ever again unless you're super tight on budget. I regret all the time and money I spent on my 452's.
The engine made the most power with a big thermoquad on it and lost power when I switched to a 750 edelbrock, it would pull vacuum at wot throttle with the edelbrock.
Posted By: Sniper

Re: Building a smogger 440 - 05/06/22 01:20 AM

Originally Posted by Uberpube

it would pull vacuum at wot throttle with the edelbrock.


At what RPM?
Posted By: GODSCOUNTRY340

Re: Building a smogger 440 - 05/06/22 02:07 AM

I can't remember who did this dyno test but they got 449 horsepower out of a smogger engine without replacing pistons. Here's how they did it.

Attached picture 0566AD90-397A-4DE0-95BF-8441C8D30137.jpeg
Posted By: Dodge

Re: Building a smogger 440 - 05/06/22 02:20 AM

What about Summit 6401 cam and rpm intake?
Posted By: SomeCarGuy

Re: Building a smogger 440 - 05/06/22 08:10 AM

What shape is the short block now? I agree it may not be the best bang for the buck to change pistons.

No way I’d run under a 750 carb on a 440. I won’t run less than that on a 383 either. Run a small carb back to back on either engine and then tell me which one you’d use. Once you feel the power you won’t run a small carb again.

A performer rpm is the best intake I’ve found for a street effort and it did great on smogger low comp 440s I had.

I agree the factory 375 hp cam is likely on target or is at least the outer limit on a truck build.
Posted By: Sniper

Re: Building a smogger 440 - 05/06/22 11:21 AM

Originally Posted by SomeCarGuy
What shape is the short block now? I agree it may not be the best bang for the buck to change pistons.

No way I’d run under a 750 carb on a 440. I won’t run less than that on a 383 either. Run a small carb back to back on either engine and then tell me which one you’d use. Once you feel the power you won’t run a small carb again.

A performer rpm is the best intake I’ve found for a street effort and it did great on smogger low comp 440s I had.

I agree the factory 375 hp cam is likely on target or is at least the outer limit on a truck build.


The OP says he wants low end power and torque.

You drag racers need to keep that in mind. Soon as you bring up a 509 cam you've far exceeded what the OP wanted.

When I swapped a 360 into my M body I ran it with a 650 carb and a 750 carb. The 650 got better mileage, low end and throttle response with less top end speed, maybe 110 mph max. The 750 had better top end speed, with worse mileage and low end. Since I don't need to go past the 125 mph mark on my speedo in a street car guess which carb was the right choice?
Posted By: B1MAXX

Re: Building a smogger 440 - 05/06/22 11:39 AM

s1263 silvolite
Posted By: B1MAXX

Re: Building a smogger 440 - 05/06/22 11:43 AM

build plan is perfect.
Posted By: Pacnorthcuda

Re: Building a smogger 440 - 05/06/22 11:46 AM

Originally Posted by Sniper
Originally Posted by SomeCarGuy
What shape is the short block now? I agree it may not be the best bang for the buck to change pistons.

No way I’d run under a 750 carb on a 440. I won’t run less than that on a 383 either. Run a small carb back to back on either engine and then tell me which one you’d use. Once you feel the power you won’t run a small carb again.

A performer rpm is the best intake I’ve found for a street effort and it did great on smogger low comp 440s I had.

I agree the factory 375 hp cam is likely on target or is at least the outer limit on a truck build.


The OP says he wants low end power and torque.

You drag racers need to keep that in mind. Soon as you bring up a 509 cam you've far exceeded what the OP wanted.

When I swapped a 360 into my M body I ran it with a 650 carb and a 750 carb. The 650 got better mileage, low end and throttle response with less top end speed, maybe 110 mph max. The 750 had better top end speed, with worse mileage and low end. Since I don't need to go past the 125 mph mark on my speedo in a street car guess which carb was the right choice?


A Holley 750 VS is a great choice for what the OP is targeting. Who brought up the 509 cam? I didn’t see that???
Posted By: Sniper

Re: Building a smogger 440 - 05/06/22 12:04 PM

Originally Posted by Pacnorthcuda



A Holley 750 VS is a great choice for what the OP is targeting. Who brought up the 509 cam? I didn’t see that???


Six posts above you by GodsCountry340
Posted By: lewtot184

Re: Building a smogger 440 - 05/06/22 12:07 PM

i've run kb184 pistons with the 6401 cam before. off idle and mid-range torque was very good. i had a stock iron intake which i think hurt the top end. you won't have that problem with the edelbrock intake.
Posted By: General Lee

Re: Building a smogger 440 - 05/06/22 12:19 PM

Hey everyone, thanks for all the help in such a short time. All my borew are perfect, not even a ridge to catch your fingernail behind, but only one has pitting. And 2 of my stock pistons are junk so i figured rebore and nice new high comp forged pistons. Im not really on a tigh budget but not going with aluminum heads right now. Can always do different heads later. Can probably get my hands on 915 or 516s, but 452 seem to do the job for many people and thats what i got now. Havent bought the 750 holley yet, but there is one for sale near me brandnew with 12 kms on it. Was overkill for his chevy 383. And cheap.
Posted By: JohnRR

Re: Building a smogger 440 - 05/06/22 12:28 PM

Originally Posted by General Lee
Hey everyone, thanks for all the help in such a short time. All my borew are perfect, not even a ridge to catch your fingernail behind, but only one has pitting. And 2 of my stock pistons are junk so i figured rebore and nice new high comp forged pistons. Im not really on a tigh budget but not going with aluminum heads right now. Can always do different heads later. Can probably get my hands on 915 or 516s, but 452 seem to do the job for many people and thats what i got now. Havent bought the 750 holley yet, but there is one for sale near me brandnew with 12 kms on it. Was overkill for his chevy 383. And cheap.


By the time you have the 452's rebuilt you are most of the way to a budget set of alum heads. Stock big block mopar heads suck plain and simple. They don't flow very well, even ported and the chambers are huge on the open chamber heads. Since you aren't budget limited , to a degree, if you insist on a forged piston get something lightweight ... like a Diamond or Ross, you might be able to internal balance it which would be a plus.
Posted By: General Lee

Re: Building a smogger 440 - 05/06/22 12:59 PM

I know they arent the best. But do i need more at the moment? Im not getting them rebuilt, just some new sprinfs and a valve job. I can always slap aluminum ones on in a year or 2 if i get tired of this setup. Dont wanna go to crazy either on a daily driver. And pump gas is a must for now, for 2 reasons. 1: Trudeaus awesome gas prices make it inefficient to run 91 octane on a daily driver, and the 440s gas mileage will already suck 2: we happen to have a gas tank here on the farm at home for the company trucks and thats obviously 87. Ya know, "ive never considered myself a thief, but the old man wouldnt miss just one little liter"😆😆😆
And for pistons, i wanna do the bottom end right in one shot, i can always screw with the top end later if i feel i need more. But not the bottom end.
Posted By: GY3

Re: Building a smogger 440 - 05/06/22 01:04 PM

One small thing that will really wake it up is recurving the stock distributor.

Cleaning and lubing the internal weights in a stock electronic distributor and installing some Mr. Gasket #925B springs will make a world of difference.

The Moroso underdrive pulley on the crank helps a little, too, and is a bolt on swap. You can find them at swap meets pretty cheap. IIRC, one of the guys here showed an 8 hp gain from one.
Posted By: moparx

Re: Building a smogger 440 - 05/06/22 03:01 PM

i like and use Thermoquads.
well sorted out, and with a good re-curved distributor, even 440's are capable of good [reasonable] gas mileage in the 13-15mpg range when one keeps his foot out [or off of] the firewall.
beer
Posted By: JohnRR

Re: Building a smogger 440 - 05/06/22 04:33 PM

Originally Posted by General Lee
I know they arent the best. But do i need more at the moment? Im not getting them rebuilt, just some new sprinfs and a valve job. I can always slap aluminum ones on in a year or 2 if i get tired of this setup. Dont wanna go to crazy either on a daily driver. And pump gas is a must for now, for 2 reasons. 1: Trudeaus awesome gas prices make it inefficient to run 91 octane on a daily driver, and the 440s gas mileage will already suck 2: we happen to have a gas tank here on the farm at home for the company trucks and thats obviously 87. Ya know, "ive never considered myself a thief, but the old man wouldnt miss just one little liter"😆😆😆
And for pistons, i wanna do the bottom end right in one shot, i can always screw with the top end later if i feel i need more. But not the bottom end.


You're not getting them rebuilt but you are getting a valve job ???? How is that not rebuilding them ?

Alum heads will help you run on 87 pump gas with your target compression AND be a performance increase.
Posted By: B1MAXX

Re: Building a smogger 440 - 05/06/22 05:07 PM

Stock rods are pressed pin, that limits your forged choices, 2355f speed -pro
Posted By: General Lee

Re: Building a smogger 440 - 05/06/22 05:10 PM

Originally Posted by JohnRR
Originally Posted by General Lee
I know they arent the best. But do i need more at the moment? Im not getting them rebuilt, just some new sprinfs and a valve job. I can always slap aluminum ones on in a year or 2 if i get tired of this setup. Dont wanna go to crazy either on a daily driver. And pump gas is a must for now, for 2 reasons. 1: Trudeaus awesome gas prices make it inefficient to run 91 octane on a daily driver, and the 440s gas mileage will already suck 2: we happen to have a gas tank here on the farm at home for the company trucks and thats obviously 87. Ya know, "ive never considered myself a thief, but the old man wouldnt miss just one little liter"😆😆😆
And for pistons, i wanna do the bottom end right in one shot, i can always screw with the top end later if i feel i need more. But not the bottom end.


You're not getting them rebuilt but you are getting a valve job ???? How is that not rebuilding them ?

Alum heads will help you run on 87 pump gas with your target compression AND be a performance increase.


Well i dont mean porting and the like. Theyre probably fine. If they dont leak ill use them. Might have to lap a valve or 2. I dont know. Will check with kerosene soon and go from there.
Posted By: General Lee

Re: Building a smogger 440 - 05/06/22 05:12 PM

Originally Posted by B1MAXX
Stock rods are pressed pin, that limits your forged choices, 2355f speed -pro


Thanks. Will they require bigger valve reliefs machined in and will i have to balance the bottom end for those?
Posted By: mgoblue9798

Re: Building a smogger 440 - 05/06/22 05:33 PM

Originally Posted by General Lee
I know they arent the best. But do i need more at the moment? Im not getting them rebuilt, just some new sprinfs and a valve job. I can always slap aluminum ones on in a year or 2 if i get tired of this setup. Dont wanna go to crazy either on a daily driver. And pump gas is a must for now, for 2 reasons. 1: Trudeaus awesome gas prices make it inefficient to run 91 octane on a daily driver, and the 440s gas mileage will already suck 2: we happen to have a gas tank here on the farm at home for the company trucks and thats obviously 87. Ya know, "ive never considered myself a thief, but the old man wouldnt miss just one little liter"😆😆😆
And for pistons, i wanna do the bottom end right in one shot, i can always screw with the top end later if i feel i need more. But not the bottom end.


Based on the new info that you need an overbore and pistons, a set of KB flat tops or TRW six pack pistons would be the budget choice. If you are planning to upgrade to aluminum heads get the block decked to zero deck the pistons. If you pick the KB's make damn sure to open the ring gap in case you decide to tow with the truck. I am opening mine to what is recommended for a nitrous application just to be as safe as possible. I would still get with Mike Jones, Hughes, or one of the other custom cam grinders to get a modern tech cam for your application.
Posted By: General Lee

Re: Building a smogger 440 - 05/06/22 06:11 PM

And by the way, i do have the stock thermoquad that came off it. It was a good running engine. I see some of you recommending this carb, so if i clean it will that work nicely with my setup? Not sure how much cfm it would be
Posted By: General Lee

Re: Building a smogger 440 - 05/06/22 06:33 PM

Im gonna go with those 6 pack pistons. Thanks folks. And any other info or thought, greatly appreciated. This is my first engine build, so every bit helps
Posted By: R/T1968R/T

Re: Building a smogger 440 - 05/06/22 06:40 PM

Originally Posted by GODSCOUNTRY340
I can't remember who did this dyno test but they got 449 horsepower out of a smogger engine without replacing pistons. Here's how they did it.

heres the article https://www.forabodiesonly.com/mopar/threads/dyno-testing-a-stock-1972-440.249866/

Posted By: B1MAXX

Re: Building a smogger 440 - 05/06/22 08:46 PM

no pocket mods, and ....no balance, they are typically made heaver than needed for that reason.Will it be perfect no but designed that way. Balancing would be recommended for obvious reasons, if desired.
Posted By: LaRoy Engines

Re: Building a smogger 440 - 05/06/22 10:02 PM

Having built that engine I too don't recommend the 509 cam for his application. Here is another low compression build using the Summit 6400 cam. In fact he is off in the mountains with it at this moment.
Mountain creeper 440
Posted By: SomeCarGuy

Re: Building a smogger 440 - 05/07/22 01:35 AM

Originally Posted by Sniper
Originally Posted by SomeCarGuy
What shape is the short block now? I agree it may not be the best bang for the buck to change pistons.

No way I’d run under a 750 carb on a 440. I won’t run less than that on a 383 either. Run a small carb back to back on either engine and then tell me which one you’d use. Once you feel the power you won’t run a small carb again.

A performer rpm is the best intake I’ve found for a street effort and it did great on smogger low comp 440s I had.

I agree the factory 375 hp cam is likely on target or is at least the outer limit on a truck build.


The OP says he wants low end power and torque.

You drag racers need to keep that in mind. Soon as you bring up a 509 cam you've far exceeded what the OP wanted.

When I swapped a 360 into my M body I ran it with a 650 carb and a 750 carb. The 650 got better mileage, low end and throttle response with less top end speed, maybe 110 mph max. The 750 had better top end speed, with worse mileage and low end. Since I don't need to go past the 125 mph mark on my speedo in a street car guess which carb was the right choice?



Not sure what a 509 cam and your 360 has to do with this? A 750 on a 383 or 440 will pick up power all over the place, including low end. Exactly why I run no less. I had a 383 that was a mileage master with a tiny carb. It also made no power. Fine in a convertible. Looking back that little carb was likely the culprit to the no power, although it helped the mpg I’m sure.
Posted By: SomeCarGuy

Re: Building a smogger 440 - 05/07/22 01:39 AM

Originally Posted by General Lee
I know they arent the best. But do i need more at the moment? Im not getting them rebuilt, just some new sprinfs and a valve job. I can always slap aluminum ones on in a year or 2 if i get tired of this setup. Dont wanna go to crazy either on a daily driver. And pump gas is a must for now, for 2 reasons. 1: Trudeaus awesome gas prices make it inefficient to run 91 octane on a daily driver, and the 440s gas mileage will already suck 2: we happen to have a gas tank here on the farm at home for the company trucks and thats obviously 87. Ya know, "ive never considered myself a thief, but the old man wouldnt miss just one little liter"😆😆😆
And for pistons, i wanna do the bottom end right in one shot, i can always screw with the top end later if i feel i need more. But not the bottom end.


The issue is the pump gas iron head build won’t be all that great if you go with aluminum heads later. Plus the cost of redoing the 452s is a long way to E street edelbrocks or the china ones that are cheaper still.
Posted By: B1MAXX

Re: Building a smogger 440 - 05/07/22 01:39 PM

This would not be the place for the 509. A cam with 228 @ .050 or less in this build. The 509 is 241*. You better be 10 to 1 or so.
Posted By: mgoblue9798

Re: Building a smogger 440 - 05/07/22 02:40 PM

If you have a good thermoquad there isn't a better carb for a street driven car or truck. Best fuel mileage of any carb when properly set up.

Get your heads CC'd after any decking and valve job. Find out how far below deck your pistons are after install. You will then have the info needed to pick a cam somewhere in the 200 to 220 @.050 range for your application.
Posted By: GODSCOUNTRY340

Re: Building a smogger 440 - 05/07/22 09:50 PM

Originally Posted by B1MAXX
This would not be the place for the 509. A cam with 228 @ .050 or less in this build. The 509 is 241*. You better be 10 to 1 or so.



I wasn't recommending the .509 cam I was just relaying what they used in their dyno test, but you have to respect that it gave it 50 more horses. That's a pretty respectable increase for a low compression engine, remember that cam was installed before they added the closed chamber 516 heads.
Posted By: Sniper

Re: Building a smogger 440 - 05/07/22 10:46 PM

I put together a spread sheet taking the starting engine combo vs the .509 cam combo. Then the end column is all the mods before the .509 swap vs. throwing in the .509 cam. Seems like under 2900 ish, the 509 setup loses to either. Above it starts to pull away. Every thing in red is where the .509 combo makes more.

Attached picture 509.JPG
Posted By: B1MAXX

Re: Building a smogger 440 - 05/08/22 01:54 AM

Originally Posted by GODSCOUNTRY340
Originally Posted by B1MAXX
This would not be the place for the 509. A cam with 228 @ .050 or less in this build. The 509 is 241*. You better be 10 to 1 or so.



I wasn't recommending the .509 cam I was just relaying what they used in their dyno test, but you have to respect that it gave it 50 more horses. That's a pretty respectable increase for a low compression engine, remember that cam was installed before they added the closed chamber 516 heads.


Yeah, I didn't think you were, just in the attachment. The idea just seemed to be catching wind.....
Posted By: Uberpube

Re: Building a smogger 440 - 05/08/22 12:42 PM

Originally Posted by Sniper
Originally Posted by Uberpube

it would pull vacuum at wot throttle with the edelbrock.


At what RPM?

Above 4k is when it really started to show, I bought the 750 off of a guy that said it wasn't enough for a 383 Chev which I doubted but it doesn't seem like it's really enough for a 440 with a dual plane. I played with it on the rollers for a few hours and tuned it in, but it was always down from the thermoquad.
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