Streetmaster to Airgap

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Hysteric said:
Nope. That's what you imagined in that head of yours.



You think asking whether a 302 head can make power is cryptic....Are you still confused? Its pretty obvious that a stock eliminator head can make more than enough power with the little cfm it flows as PHR posted yet you cant accept that a 302 head that flows 200 cfm has the potential to do the same. Its incredible how the mind can accept a reality for one person but not that same for another....... Must be a Chevy can do it but a Mopar cant thing.

What this thread has clearly shown is that on that engine going from a tiny intake manifold port window to a larger one didn't make much of a difference at 5600 RPM, 16 HP to be precise. How much extra CFM did the engine use to make that extra 16 HP @ 5600 RPM? If that area was going to be a restriction it would have shown up but it didn't.

200 cfm is 200 cfm and if you can use it you'll make power no matter what head it is and what brand. But it seems to me that its only when its a Mopar 302 head and ME posting that the rules change in the land of physics.
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Your hallucination and contradiction is noted.

You still get nothing right.
 
So this thread has turned into vomitous regurgitation about how badass 318 heads and a 318 intake are. ok.
 
RustyRatRod said:
So this thread has turned into vomitous regurgitation about how badass 318 heads and a 318 intake are. ok.
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And that 16+ hp is meaningless.
I don't think I've met anyone who would turn down a 5%+ bolt on. Have you?

Given the OP was about the gain from an intake swap on an otherwise stock 340 - a more constructive question would be, now much gain is a reasonable one for only a manifold swap? Obviously something with headers, heads, and more cam would see a bigger gain, but for a stock motor?

Personally I think 16 hp is worth every dollar that an air gap costs, especially knowing that the later addition from headers, carb, and cam will be even greater with the intake there.

Then again, which is worth doing first? Intake, or headers?

Personally, I'd probably start with headers, then intake, but if I pull an intake I'm not leaving a stock cam in it.. That's just me.
 
Phreakish said:
And that 16+ hp is meaningless.
I don't think I've met anyone who would turn down a 5%+ bolt on. Have you?

Given the OP was about the gain from an intake swap on an otherwise stock 340 - a more constructive question would be, now much gain is a reasonable one for only a manifold swap? Obviously something with headers, heads, and more cam would see a bigger gain, but for a stock motor?

Personally I think 16 hp is worth every dollar that an air gap costs, especially knowing that the later addition from headers, carb, and cam will be even greater with the intake there.

Then again, which is worth doing first? Intake, or headers?

Personally, I'd probably start with headers, then intake, but if I pull an intake I'm not leaving a stock cam in it.. That's just me.
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I always ask the question.....and I am sure you've seen me do it......how much grass will that cut? 16HP. How much grass? A frigton. I guarantee you that you will feel a 16HP addition. It's a good add for just an intake swap.
 
RustyRatRod said:
It's worse than the original Edelbrock Torker. If that's even possible. Both good for doorstops.
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It was OK for that in between intake. That huge plenum was not a help for a street ride. If given a healthy cam & gear behind it, it wasn’t to bad IMO.
 
rumblefish360 said:
It was OK for that in between intake. That huge plenum was not a help for a street ride. If given a healthy cam & gear behind it, it wasn’t to bad IMO.
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Yeah probably "better" than what we are talking about here. But don't forget, a big plenum is the secret to the bottom end torque some intakes have. Case and point, the magical Street Dominator. Also the old Edelbrock Street Tunnel Ram with the BIG balloon top. But you know like I do, that the big plenum has to have everything else to make it work. Good runner shape and size. With small runners, a big plenum can be a bad recipe.
 
How much power can a 302 head make?

Well, on the same 318 short block, with the same cam, headers, intake, carb, etc...... with the CR between the heads equalized....... the 302’s make 40hp less that some equally prepared 596’s.

A 150hp 318 from a 78 Aspen wagon is NHRA factored to 230hp.
The weight break for O/SA is 15lbs/hp, so at 230hp the car min weight is 3450. Add 170 for the driver and min weight driving over the scales is 3620.
 
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PRH said:
How much power can a 302 head make?
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That’s a very good question.
(Actually, that is the question!)

Well, on the same 318 short block, with the same cam, headers, intake, carb, etc...... with the CR between the heads equalized....... the 302’s make 40hp less that some equally prepared 596’s.
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Now where getting somewhere.
Would this be on a 318 or 360 engine?
What was the head prep consisting of?
 
318willrun said:
First of all, Stocker's get most of the ET in the 60 ft. Start with 4.88's and a 5400 stall. 2nd of all, they use about 320 duration to keep the rpm's high. Many will spend a few grand on getting the "most" from what may be a bad head from the factory. All the rest of the HP is hunt and peck
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Dont know where you get your cam specs from......friends in the business say about 260ish degrees at .050....Call Don Little in California...he does a LOT of Mopar stocker cylinder heads.....bring your Visa card...cause he charges about 3 grand
 
PRH said:
How much power can a 302 head make?

Well, on the same 318 short block, with the same cam, headers, intake, carb, etc...... with the CR between the heads equalized....... the 302’s make 40hp less that some equally prepared 596’s.
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Is it fair to say that that 125 cc intake port head was only down 20 cfm on that 160 cc port to only show a 40 HP difference?
 
70aarcuda said:
Dont know where you get your cam specs from......friends in the business say about 260ish degrees at .050....Call Don Little in California...he does a LOT of Mopar stocker cylinder heads.....bring your Visa card...cause he charges about 3 grand
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My point was spot on. So many like the .. "ran this ET off of this head", or "this ET with only .427 lift" (referencing stockers) as if those parts are what get you there. It's not. It's everything they do around the "cogs in the wheel" to get the ET, and it often cost lots of money.
 
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318willrun said:
My point was spot on. So many like the .. "ran this ET off of this head", or "this ET with only .427 lift".... as if those things are what get you there. It's not. It's everything they do around the "cogs in the wheel" to get the ET, and it often cost lots of money.
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Efficiency is the key.
 
Hysteric said:
Is it fair to say that that 125 cc intake port head was only down 20 cfm on that 160 cc port to only show a 40 HP difference?
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Yes...... and no.
22cfm difference.....@10”.
100cfm vs 122cfm

These were oval track motors built to fit a specific set of rules.
Mopars could run as big as 318” +.030.
Stock stroke, 10:1cr, stock type pistons only, stock rods, stock cranks, stock non-HP heads, no head porting, factory iron 2bbl intake manifold, with adapter and a 4412 Holley carb.
Any flat tappet cam, roller rockers okay, headers.
The valve size rule was 1.88/1.50.

The previous year they had put 1.88’s in one set of the 302’s they were running, and felt that was a minor improvement over the 1.78’s.
I took that set and did some tweaking to the bowls of that set to improve the form in the bowl with the bigger valve.

The 596’s got ex seats installed to facilitate the 1.50 valves.

The previous year(built by someone else) the motors made around 275hp.

When I built the first motor it made 293hp with the 302’s.
Just like they do it on Enginemasters TV, we swapped to the 596’s right on the dyno.
The motor made 330hp+ with the 596’s.

At the faster tracks, with the car really hooked up, they would turn right about 7k and the end of the straights.
 
What was the head prep consisting of?
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Reconditioning the head(guides, seats, etc), milling for correct CR, cutting for dual springs and posi seals.

I had just bought my first flow bench and spent some time playing with valve jobs, different valves, bowl cuts, etc.
 
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fishmens67 said:
Velocity for one.
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Where do you think that fits into our discussion?

PRH said:
Yes...... and no.
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PRH said:
How much power can a 302 head make?
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Back to this question once again. How much power can it make? Seems like everyone has a hard answering it. Can a 302 head flow enough air to make a 3400 pound car run 11's?

I'm not interested in cost, time or energy just can it do it. Its a Yes or NO answer.
 
Hysteric said:
Is it fair to say that that 125 cc intake port head was only down 20 cfm on that 160 cc port to only show a 40 HP difference?
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No it’s not “fair” whatever that means. CFM isn’t a good predictor of cylinder head performance.
 
Hysteric said:
Where do you think that fits into our discussion?





Back to this question once again. How much power can it make? Seems like everyone has a hard answering it. Can a 302 head flow enough air to make a 3400 pound car run 11's?

I'm not interested in cost, time or energy just can it do it. Its a Yes or NO answer.
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How do you not account for time? That’s silly. Why piss away time (money) and end up with the same result? Start with a better head and save money.
 
Rat Bastid said:
How do you not account for time? That’s silly. Why piss away time (money) and end up with the same result? Start with a better head and save money.
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You avoided answering the question. The WHY's are irrelevant just the CAN's matter at this point. CAN IT OR CAN'T IT? Its a straight forward question.
 
I have no idea how much power 302 heads can ultimately make.

What I do know is they can certainly make 293hp.
Cuz I’ve done that.

When you get your car into the 11’s with your 302 heads, then you’ll know absolutely positively it can be done.
 
Hysteric said:
Then what is?
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Cross section, shape and then maybe flow. Maybe. My question to you is a simple one. Would you spend 5k to make a 302 head make 420 hp or 2500 to make 480 hp, because that’s the cost difference between a set of stocker heads and a set of TF heads. And the two aren’t even in the same class.

BTW, I read one of the links on gtxjohn and I didn’t see what class he was running a 318 in with 302 heads. How about letting us know exactly what Carr and class we are talking about.
 
Hysteric said:
You avoided answering the question. The WHY's are irrelevant just the CAN's matter at this point. CAN IT OR CAN'T IT? Its a straight forward question.
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Let me say it this way. You can’t put enough money into a 302 head to make it a TF head. It will never be that. If you like a dick measuring contest to prove you can sit at the porting bench and kill yourself just to show you are the smartest guy on the block then go ahead. Stupid is stupid and spending any more than 500 bucks on those heads is dumb. So I don’t care how much power you think you can make with them, I know I can make more with a TF head. Or a Speed Master head. And not spend the time or the money doing it.
 
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