Streetmaster 318???

[slipyoke]

Hey guys im new to A-Bodies and new to the mopar crowd. Im a X jeeper thats trying his hand at hoarse power. SO i have a 76 duster with a 318 that my grandpa passed on to me and she is in perfect stock shape. Now as i understand that year of 318 is detuned so im trying to add some hoarse power to her. I came up on a streetmaster 318 intake man part #37744463 now should i hold on to it or find somthing better. I also have a 1405 edlbrock carb to through on her too?

I am a big ol newb so anyhelp would be awesome guys. thanks

 

[MopaR&D]

Typical and proven performance hop-ups to a 318 include dual exhaust, 4-bbl. carb, and cam/lifters/valvesprings for starters. I'd personally recommend first getting dual exhaust off the stock manifolds (crossover does help too but it's arguable at this level of HP). Then swap on a good dual-plane intake such as the Edelbrock Performer and a 4-bbl. carb such as your 1405 which is a 500 cfm model. Then if you want to go further I'd recommend first getting some good replacement cylinder heads (such as the #302 casting heads from the late 80's) because the ones on your engine are pretty awful flow-wise. Combine that with a good cam (Lunati Voodoo series is great, I have one in my Duster) and some higher-compression pistons (if you want to go that far) and you'll have a screamer. Really with classic American performance you can go as far with the engine as you want; you could build a 400 HP 318 for not too much money, but then again a 360 is an easier choice. I have a 1970 Duster with a 318 and so far it has an iron 4-bbl. intake off a 360, a Carter Thermo-Quad carb, and Lunati Voodoo 256/262 cam with Comp 901 valvesprings. It's still kind of sluggish though because it still has the tiny single exhaust and stock torque converter with 2.76:1 rear end gears (plus my secondaries aren't working right which definitely doesn't help).

 

[Badart]

Here is a 318 combo that I am building right now on a budget. I have it together and just need to drop it in the dart. I may have $1200 into it. You can build a decent daily driver for pretty cheap if you are willing to turn a wrench. My advice would be to look for a set of Magnum heads from a Dodge/Jeep 318-360. They will bolt right up to your LA block and have closed chambers, bigger valves flow so much better. I pulled my set myself for $75 for the local wrecking yard. If you go with a moderate cam like me you can run chevrolet springs and retainers on them for much less than the mopar performace replacments. You will need the conversion pushrods through mopar performace. Here are the links on a couple of my posts.
http://www.forabodiesonly.com/mopar/showthread.php?t=65469
http://www.forabodiesonly.com/mopar/showthread.php?t=66298

 

[72bluNblu]

The streetmaster 318 is a decent intake, its a single plane but because of the small ports in maintains port velocity pretty well. The edelbrock performer, and especially the performer rpm or rpm airgap are better manifolds, but if you can get the streetmaster for a decent price ( I got mine for about $100) its a good intake.

The 1405 is ok, but 500cfm is a little on the small side I think. It'll work fine for street use, but it'll be a touch small at high rev. I have a 625 cfm carter AFB on my 318 with my streetmaster intake and it works well, I had to jet it down a little (2 sizes on the primaries and 1 on the secondaries) but it pulls hard and is pretty responsive considering my freeway gears and stock 904 transmission. Only other mods I have are a set of 1 3/4" hooker super comps (this 318 is in my challenger). Overkill for the 318, but they're for the 340 that will go into it later.

With the carb, intake and headers though the 318 is a whole different animal than it was stock, feels much stronger and more responsive than with the manifolds and stock 2 barrel. A cam would be a big help too, but with a new engine going in mine I'm skipping it.

 

[slipyoke]

Hey thanks a lot guys! A lot of good info.

 

[72bluNblu]

Took for granted the 1405 was a 500 cfm, its actually a manual choke 600 CFM Edelbrock Performer. A good carb for a street driven 318!

 

[4DrSwingr]

Took for granted the 1405 was a 500 cfm, its actually a manual choke 600 CFM Edelbrock Performer. A good carb for a street driven 318!

When you installed the street master did you have any issues with manifold bolt clearance? I’m about ready to install one and I realized the Center bolts won’t make it past the runners.

 

[RustyRatRod]

If you HAVE that intake now, use it. It's a purdy goodun.

 

[4DrSwingr]

If you HAVE that intake now, use it. It's a purdy goodun.

I’m really hoping I can. I just need to figure out the bolt situation, maybe there’s some sort of stud kit I can use. Or I might try and grind some clearance. We’ll see I guess. Lol

 

[RustyRatRod]

I’m really hoping I can. I just need to figure out the bolt situation, maybe there’s some sort of stud kit I can use. Or I might try and grind some clearance. We’ll see I guess. Lol

Can you elaborate on the "bolt situation"?

 

[4DrSwingr]

Can you elaborate on the "bolt situation"?

Sorry, the four Center manifold bolts won’t clear the intake runners. I’d really rather not grind away at them, but I’m hoping there’s another option.

 

[33IMP]

Sorry, the four Center manifold bolts won’t clear the intake runners. I’d really rather not grind away at them, but I’m hoping there’s another option.

Header bolts with reduced heads.
Or, socket head capscrews.
If it's within budget: full set of stainless socket heads, and a drive socket f9r your torque wrench.

 

[4DrSwingr]

Header bolts with reduced heads.
Or, socket head capscrews.
If it's within budget: full set of stainless socket heads, and a drive socket f9r your torque wrench.

I will absolutely look into that. Thank you

 

[AJ/FormS]

I hope you realize that the 4bbl by itself, will not add even one horsepower until the 318 gets up to an rpm where she starts to pull more air than what the 2bbl can currently provide.
And when it finally does, it will begin by adding perhaps 1 horsepower per 100 rpm.
Suppose, your 2bbl runs out of capacity at 3000 rpm.
Suppose you have 2.76 gears, and 25.5" tires.
And a regular A904 trans,
With these parameters, 3000 is about 32 mph @WOT.
All that cash for same old bottom end.
Installing a cam, without punching up the cylinder pressure, to at least back to what it now is, will only make it worse.
What you need is a higher than stock stall, and I like a 2800.
Nothing you do to your stock 318, short of supercharging will make as big a difference as a Convertor.
Suppose your 318, right now, with the 2 bbl, can muster 200 ftlbs at a current stall of say 1800. By the math, that is 68hp.
If you installed a 2800, and say the engine never makes more than the same 200ftlbs but now at 2800. By the math, that is 107 hp. an increase of almost 57%!! Have I got your attention?
But the fact is, that your 318 will be making MORE torque at 2800, than it made at 1800. Lets say it gets up to 240 ftlbs. By the math at 2800, that would be 128hp an increases of 88%.
So;
Just buy/install a 2800 Stall convertor; you can thank me later.

The numbers I used may not translate directly to your engine, but it doesn't matter, cuz the end result will be the same, which is screaming tires and a big effing ear-to-ear smile.

 

[273]

I hope you realize that the 4bbl by itself, will not add even one horsepower until the 318 gets up to an rpm where she starts to pull more air than what the 2bbl can currently provide.
And when it finally does, it will begin by adding perhaps 1 horsepower per 100 rpm.
Suppose, your 2bbl runs out of capacity at 3000 rpm.
Suppose you have 2.76 gears, and 25.5" tires.
And a regular A904 trans,
With these parameters, 3000 is about 32 mph @WOT.
All that cash for same old bottom end.
Installing a cam, without punching up the cylinder pressure, to at least back to what it now is, will only make it worse.
What you need is a higher than stock stall, and I like a 2800.
Nothing you do to your stock 318, short of supercharging will make as big a difference as a Convertor.
Suppose your 318, right now, with the 2 bbl, can muster 200 ftlbs at a current stall of say 1800. By the math, that is 68hp.
If you installed a 2800, and say the engine never makes more than the same 200ftlbs but now at 2800. By the math, that is 107 hp. an increase of almost 57%!! Have I got your attention?
But the fact is, that your 318 will be making MORE torque at 2800, than it made at 1800. Lets say it gets up to 240 ftlbs. By the math at 2800, that would be 128hp an increases of 88%.
So;
Just buy/install a 2800 Stall convertor; you can thank me later.

The numbers I used may not translate directly to your engine, but it doesn't matter, cuz the end result will be the same, which is screaming tires and a big effing ear-to-ear smile.

Fairy tale, what a bunch of made up non sense, only making 200 lbs-ft based off what ? your imagination, zero hp gain and then only 1 hp per 100 rpm again based on what ? your imagination dyno, ridiculous lol.

 

[72bluNblu]

When you installed the street master did you have any issues with manifold bolt clearance? I’m about ready to install one and I realized the Center bolts won’t make it past the runners.

Yes, the center bolts are a PITA.

I believe what I did was buy an ARP intake manifold bolt kit with the smaller head on them, takes a 3/8” socket or wrench.

 

[RustyRatRod]

Sorry, the four Center manifold bolts won’t clear the intake runners. I’d really rather not grind away at them, but I’m hoping there’s another option.

Just use a manifold bolt set with 3/8" 12 point heads. Problem solved. These will work fine. Don't forget to put sealant on the bolt threads. The intake threaded holes in the heads go all the way through into the valve cover area. Oil can migrate up the threads and pool on the outside of the intake of you do not use sealant.

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[junkyardhero]

Fairy tale, what a bunch of made up non sense, only making 200 lbs-ft based off what ? your imagination, zero hp gain and then only 1 hp per 100 rpm again based on what ? your imagination dyno, ridiculous lol.

his imagination dyno to go with his imagination car. just another page out of the AJ 318 hater manifesto.

 

[72bluNblu]

Just use a manifold bolt set with 3/8" 12 point heads. Problem solved. These will work fine. Don't forget to put sealant on the bolt threads. The intake threaded holes in the heads go all the way through into the valve cover area. Oil can migrate up the threads and pool on the outside of the intake of you do not use sealant.

http://[URL]https://www.summitracing.com/parts/sum-910505/make/dodge

[/URL]

Maybe it’s just me, but I don’t think I’d put 12 points there. It’s just tight on those inside runners, and being able to use an open ended wrench comes in handy sometimes.

And I get you’re not gonna torque those to spec with an open ended wrench. But sometimes in those tight spots being able to get an open ended wrench in there is nice.

 

[RustyRatRod]

Maybe it’s just me, but I don’t think I’d put 12 points there. It’s just tight on those inside runners, and being able to use an open ended wrench comes in handy sometimes.

And I get you’re not gonna torque those to spec with an open ended wrench. But sometimes in those tight spots being able to get an open ended wrench in there is nice.

You could be right. Might be best to use a bolt with a 3/8" six point hex head.

 

[33IMP]

You could be right. Might be best to use a bolt with a 3/8" six point hex head.

I have modified a couple offset-head 7/16 wrenches for header bolt access. They would also work perfectly (and have) on header style bolts used on difficult access intake bolts.

 

[6T9QDA]

I love these threads that jump sixteen years like they never even happened.

 

[Lift&Move]

Lol...yeah!
Reminds me of a scene in the movie "The Cowboy Way"

 

[72bluNblu]

I love these threads that jump sixteen years like they never even happened.

Right?

Honestly I think it's pretty cool in some case. FABO is kind of unique like that, I mean how many forums are there where if you revive a 16 year old thread you actually get some of the original members answering back? Obviously it's not the only one out there, but there are definitely forums where if you bring a thread back from more than a couple years before you're just gonna get crickets.

 

[toolmanmike]

Right?

Honestly I think it's pretty cool in some case. FABO is kind of unique like that, I mean how many forums are there where if you revive a 16 year old thread you actually get some of the original members answering back? Obviously it's not the only one out there, but there are definitely forums where if you bring a thread back from more than a couple years before you're just gonna get crickets.

I was curious so I looked it up. It will be 20 years in Janruary for me and I'm not an old timer here.