Inputs on a home built 318 for red light to red light fun

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Ok im seeing I left a ton on information out and I've been called put in many posts about it so I think if I cover those bases I might get a better run on this I'm looking to try and make a 1967 and back super stocker that's can be driven on the street through a small town not long road trips. Lw ght of wanting to hit top end is 1/8 mile 4 speed is a mist refused to go automatic. The block I have is a 1970 dodge power wagon 318 with a cast crank I wanted something that reved higher or the same as the poop bowtie I had 4 years ago which was 6600rpms. Some have a low budget I have a empty pocket budget all my stuff I've gotten for free found or traded stuff for. Head wise I have the 64-65 273 54cc heads the stock 675 heads and a set of 360 heads casting 3769974. I do not have the funds to bore it the pistons I seen and had plans to go that route as it would be something I bough at taxe time that I wouldn't need to bore it to help make more power. I've gotten really good with porting so that don't scare me to go in and hog a set out. I'm trying to go against 7.9x.xx 1/8 Mike new gen c&f guys thay are younger then me that I would like correct them that even a old *** small block can beat or hang with them but do this based on a 1967 super stocker rule book with I have found online and the car I'm choosing to use is a 1966 dart gt thay has had the wheel wells cut to fit a nice fat tire for bite or even a drag slick or if need be a cheater slick . If I missed something that anyone needs to know to help im more then happy to answer... im open to here what I can do with what I go guys and gals as I said this is my first motor build.
 
Dan the man said:
If I read the OP correctly, he's wanting to build his car for stop light to stop light fun. His combination is off. He wants a cam that will let him spin the 318 to 7,500 rpm's, the cylinder heads just won't support that rpm, neither will those 273 rocker arms.
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Actually these parts will. They have nothing to do with rpm. What these parts have to do with is; Heads, moving the air. The valve springs control the valves which are rpm limited due to design or weight of the valve. Rocker arms have there job as well which there not a limiting factor on rpm ether. As long as there constantly oiled, they work.
He has a heavy crankshaft, rocker arms.
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The weight of the crankshaft is not a limitation to rpm but a limitation on how fast it will spin from idle to max rpm. The weight of the rockers can limit valve control at some point if the spring can not control them. OEM rockers have turned these rpm’s before.
No mention of a intake manifold either but he will need a single plane.
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The intake can be rpm limited in terms of making power. But if the engine otherwise can turn 7500-8500, the intake is still moving the air. Power wise, yes, a single plane is better and hence why I posted the tunnel ram.

If he was to build it with the parts that he listed I think that the car would be a dog off the line. A 3.91 or even those 4.30 gears are going to make that 318 scream at cruising speeds.
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This is a broad statement and you can not actually predict this since the specifics of the build are far far from being listed and have a ton of unknowns not to mention what your saying, “A dog off the line” is part of the way it’s built and a known factor with exception to the gear ratio mention which is wrong. The increased axle ratio is done so as to release more torque to ease driving and release more power quicker to accelerate best.

Besides, what’s cruising speeds on the boulevard when that could only be 30-40mph? It’s not the facet goal, just a minor requirement in order to get there.
I knew a guy that had a 383 with a 1050 Holley denominator and it was a dog off the line, carb was to big. He put a 850 on it and it ran great.
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Not so sorry to hear you know of a guy that can’t tune a carb. Sorry to read you use him as a end all example.
I may not have the years experience that most on here have but I do know that he's combination is as mismatched as it can be.
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His combo is a question he brought forth as a parts list seeking help. I have a (jokingly funny) description of what he sounded like. Re read my posts.

Your lack of experience shows and that’s OK.
Giving advice with a lack of experience, I don’t think that’s wise.
Giving advice due to others experience is not good ether but a mention of someone else’s been there and done that experience should at least be mentioned as such and not a bar that was set. Just a report on how they did with it would be good.
 
@Branden Finkenbinder Now that you wrote a goal down, 7.9xxx, I can translate this in my head and to the 1/4 mile time of a mid 12 second drag car which will require a certain amount of power at a certain weight.

Do you know your cars weight?
 
This is what I would do. It maybe a slight overkill, but, I will call that an error on caution as 12’s in the street IMO is not what I’d call fast anymore.

Based on your listed parts in your first post & with a minimal change in parts, I would;

Shot for a compression of no higher than 10.5-1 with the iron heads. You’ll probably require 93 octane to run this. A 1/2 point in compression down @ 10-1 is safer and not a huge issue.
Select a piston for this job.

Going from top to bottom of the engine;
K&N filter lid on a K&N filter with as much height as the hood allows & to be honest, going through the hood for air filter clearance should be done. Use a hood scoop to help feed the carb and seal the carb to the hood.

Carb - A 750 Holley. A capable and inexpensive model like a Brawler can be used effectively.
Intake - RPM-AG deep port matched.
Cylinder head - 1.88-1.60 valves race prepped in a race ported 318 head. Equip the head with the valve springs for the cam suggestion below with the matching valve springs of the cam along with race styles 7* retainers and locks.
Your rocker arms are OK. I’d rather move to aluminum roller rockers. But using what you have, you can help out the package by having the rockers worked on and set up for a true dead on 1.5 ratio.

I normally do not give cam advice anymore since that’s a big can of worms. But I will say that the old MP books suggest there cam. There very expensive and the one below is maybe available today though another maybe substituted. It’s the MP mechanical cam, 296-.557-110, part number 4120655. I’d search for a similar cam.
Headers - I may catch flak for the suggestion of a 1-3/4 header, but that what I would do myself. Into a 2-1/2 exhaust. If you dyno this engine, find out the length of pipe past the header collector that makes the most torque and cut it there and add a pressure wave cancellation box. The pipe should be the same size as the collector and only reduced in size after the cancellation box in a smooth manor. The cancellation box should be the same cubic inches as the engine at a minimum.

The rest of the car…. Scatters shield for the clutch, driveshaft safety loop, 4.88 gears (since you have them?) Super stock springs though I like the Caltrac or Assassin leaf spring set up better. 9X28 tires. Street slicks. (Slicks with tread) Move your battery to the trunk. Install and electric fuel pump and regulator, light weight wheels, frame connectors & torque boxes, up the ignition abilities. Lighten the car up as much as possible

I myself would rather use ported Edelbrock heads. As the iron is expensive to get worked on. I’m not experienced on porting and if I tried, my hands are not vibrant enough anymore to hold the die grinder long enough to get a port done in a week much less the other 15 ports.
 
Oh WOW! Nice and light OOTB, very nice. My ‘70 Duster is like that. It was a /6 that I swapped to a small block. Given the aluminum heads, intake and headers, it’ll weigh in less than the stock delivered car was. The part that’s gonna suck weight wise is adding in the roll cage & subframe connectors. But there a good thing. It’s also in a better place on the car, not up front.
 
rumblefish360 said:
Actually these parts will. They have nothing to do with rpm. What these parts have to do with is; Heads, moving the air. The valve springs control the valves which are rpm limited due to design or weight of the valve. Rocker arms have there job as well which there not a limiting factor on rpm ether. As long as there constantly oiled, they work.

The weight of the crankshaft is not a limitation to rpm but a limitation on how fast it will spin from idle to max rpm. The weight of the rockers can limit valve control at some point if the spring can not control them. OEM rockers have turned these rpm’s before.

The intake can be rpm limited in terms of making power. But if the engine otherwise can turn 7500-8500, the intake is still moving the air. Power wise, yes, a single plane is better and hence why I posted the tunnel ram.


This is a broad statement and you can not actually predict this since the specifics of the build are far far from being listed and have a ton of unknowns not to mention what your saying, “A dog off the line” is part of the way it’s built and a known factor with exception to the gear ratio mention which is wrong. The increased axle ratio is done so as to release more torque to ease driving and release more power quicker to accelerate best.

Besides, what’s cruising speeds on the boulevard when that could only be 30-40mph? It’s not the facet goal, just a minor requirement in order to get there.

Not so sorry to hear you know of a guy that can’t tune a carb. Sorry to read you use him as a end all example.

His combo is a question he brought forth as a parts list seeking help. I have a (jokingly funny) description of what he sounded like. Re read my posts.

Your lack of experience shows and that’s OK.
Giving advice with a lack of experience, I don’t think that’s wise.
Giving advice due to others experience is not good ether but a mention of someone else’s been there and done that experience should at least be mentioned as such and not a bar that was set. Just a report on how they did with it would be good.
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His choice of cylinder heads will keep him from reaching his goal, as I said earlier, there are a small port small valve cylinder head and they will hinder the performance of a cam that he wants to spin it 7,500 rpm's. Am I correct here?
 
Dan the man said:
His choice of cylinder heads will keep him from reaching his goal, as I said earlier, there are a small port small valve cylinder head and they will hinder the performance of a cam that he wants to spin it 7,500 rpm's. Am I correct here?
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Had plans to port them and put in larger valves or won't that make a difference?
 
Branden Finkenbinder said:
Had plans to port them and put in larger valves or won't that make a difference?
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Porting along with bigger valve's will help, but the overall port size will still be to small to support 7,500 rpms. You need cylinder heads that have bigger intake runners, like 170cc or 180cc. Those 273 rocker arms are probably 50+ years old and I wouldn't trust them for your application. Some on here will probably disagree with me but those rocker arms have been known to break. You'd be better off with a set of aluminum roller rockers. What intake manifold you plan on getting?
 
Branden Finkenbinder said:
Hey everyone youngster here about to built a 1970 318 for a 1965 dodge dart gt 2 door. the dart will be a all steel car 4 speed with 4.10 or 4.88 gears 8 1/4 rear stock suspension other then front disks as for motor it will be built as the following

1970 318 stock bore

KB 10.5-1 pop up pistons

273 hipo rods or some form of a lighter rod

318-3 truck crank

0.27 head gaskets

1965 273 hipo 54cc closed chamber heads with
adjustable rockers Ported as far as I can with out thin walls both exhuast and intake 3 angle valve job with 1.88 360 valves

Solid mechanical camshaft good for 7500 and up rpms

273 4 barrel intake or a d4b intake if I can get one cheap enough

Holley 750cfm double pumper

Just would like to here yalls input from those who are wiser then me as I'm only in my early 30s and this is my first on my own build
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You don't want to use dome pistons. You'd be better off with having your block zero deck. I don't think that you can run a 0.027" thick gasket. I think that you would be better off with a quench distance of 0.039". Having the block decked and squared is a good idea too. Quality machine work and parts are important. I don't know why you want to spin your 318 to 7,500 rpm's, for some reason everyone thinks that you have to spin it to make power, not true. Your combination is all mismatched, big carburetor, you didn't mention a intake manifold and the cylinder heads have way to little valves and ports for your intended goal. From what I've read on your op, I think that you would be happier if you built your engine for better throttle response and low to midrange torque, I say this because you didn't mention that you were building a race car.
 
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Yes a 318 the smallest most of us will build, but really not by that much, a 360 is 13% bigger a 318 will need about 13% more rpm than a 360 to make same ish power.
 
Ottmundr said:
have you considered some junkyard magnum heads or some 302 heads off rockauto?
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Magnum heads would increase the cost of the build as they have to be checked for cracks and the cost of a magnum only intake manifold. I was lead to believe that the 302 heads are no longer available, does rock auto have them?
 
I don't think some people realize how little of rpm is needed, most stock low powered engines like a 318 make peak power 4000-4500 rpm basic truck powerband, trick for street builds is extend the powerband to 5000 ish rpm peak power without trading too much down low, at this range with the right parts you should be able to 0.9-1:1 hp per Cid.

For hotter street engine move peak power to 5500 rpm for a 1.1:1 hp:Cid but will probably need gears stall since under 2500 rpm will start becoming soft.

This is why most for street say no replacement for displacement cause to this point rpm is kind of fixed so displacement allows more hp to be made at these narrow street rpm ranges.

Above this is more street strip type engine peak power 5500-6500 rpm 1.1-1.4:1 above this your more into race of at least barely street, now there's many ways to do things and I'm sure someone out there has built an 8000 rpm daily drive that get's 25 mpg but this is ruffly how it goes down.
 
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From what I understand what the op is wanting to do, I think that a 500 - 600 cfm carburetor would be good along with a good dual plane intake. 302 heads with a good comp valve job and back cut the valve's. Cam wise I'd say a 340 or similar cam. Have the block decked so pistons are at zero deck height, good quench will help with detonation. I'm thinking that if he builds as he posted that he will be disappointed. He would need at least a 3500 stall converter for the cam he would need to spin 7500 and now he would have transmission heat problems.
 
Dan the man said:
From what I understand what the op is wanting to do, I think that a 500 - 600 cfm carburetor would be good along with a good dual plane intake. 302 heads with a good comp valve job and back cut the valve's. Cam wise I'd say a 340 or similar cam. Have the block decked so pistons are at zero deck height, good quench will help with detonation. I'm thinking that if he builds as he posted that he will be disappointed. He would need at least a 3500 stall converter for the cam he would need to spin 7500 and now he would have transmission heat problems.
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Your recipe is a nice mild one for a teen. Probably a 5500 rpm engine with 300 horse.
 
Dan the man said:
From what I understand what the op is wanting to do, I think that a 500 - 600 cfm carburetor would be good along with a good dual plane intake. 302 heads with a good comp valve job and back cut the valve's. Cam wise I'd say a 340 or similar cam. Have the block decked so pistons are at zero deck height, good quench will help with detonation. I'm thinking that if he builds as he posted that he will be disappointed. He would need at least a 3500 stall converter for the cam he would need to spin 7500 and now he would have transmission heat problems.
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Don't understand why 302 heads, yes if you had a good running 318 add a basic mild cam 4bbl and headers is a no brainer, but doing a full build why strangle the power with 273/318 heads, say your combo good for 300 hp, just swap to 1.88 360 would gain 30-40 hp will no real downside, go Speedmaster or eddy's and another 30-40 hp.

And even if 300hp if fine with better heads you can go smaller on cam the get there.

Yes 600-650 cfm fine, a 500 cfm is on the small side just giving up power for no reason.
 
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Dan the man said:
His choice of cylinder heads will keep him from reaching his goal, as I said earlier, there are a small port small valve cylinder head and they will hinder the performance of a cam that he wants to spin it 7,500 rpm's. Am I correct here?
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Yes and no. It’ll spin that high of the valve springs control the valve. The head will flow only so much air, any head, this is a limitation to power, not rpm.
I said this earlier.
Branden Finkenbinder said:
Had plans to port them and put in larger valves or won't that make a difference?
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Yes, it’ll make a difference. More power up top.
Dan the man said:
Porting along with bigger valve's will help, but the overall port size will still be to small to support 7,500 rpms.
This is incorrect and I’d wish you’d stop saying that. It just shows those who know you don’t know what your talking about and your giving ill advice in this manor.
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You need cylinder heads that have bigger intake runners, like 170cc or 180cc. Those 273 rocker arms are probably 50+ years old and I wouldn't trust them for your application. Some on here will probably disagree with me but those rocker arms have been known to break. You'd be better off with a set of aluminum roller rockers. What intake manifold you plan on getting?
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I agree on more cylinder head. Even more than you suggest. The rockers can hold only so much spring pressure. The Hyd or solid cam springs should be just fine for this. This is also why I suggested to have them looked over and have the ratio corrected. If there is a short coming round, you’ll be told.
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