Tunnel ram Tuesday!!!...

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TC67CUDA said:
It is a stock block .030 over 440, 4.15 stroke (493cid), solid flat tappet 272/280@.050 664/640 lift, Indy SR’s, 12.5:1 flat tops, Indy tunnel ram with 750 carbs

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Pretty nice combo, what gears and trap rpm ?
I think my cam in my 470 is too small and your cam is in a range I'm thinking of going.
Thanks for sharing
 
MOPARMAGA said:
Pretty nice combo, what gears and trap rpm ?
I think my cam in my 470 is too small and your cam is in a range I'm thinking of going.
Thanks for sharing
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Thanks MOPARMAGA
I’m running 4.56 gears, 5000 stall, 33” tires and traps around 67-6800
 
Not Tuesday but here’s a tr5 I’m working on

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My old school looks "extra" HEMI tunnel ram for display in the Racement (racing themed basement). Keith Black Hemi block and twin plug Stage V heads.
And, a couple more of the other 528" tunnel ram HEMI in the car.

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Newbomb Turk said:
Excellent work!!! What every tunnel ram from that era should look like. It’s hard to get enough area without welding.

Very cool.
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I’m sure you know on these intakes the top wall curves/pinches down more than the floor. By welding I can match the head port and basically remove that curve and blend it into the top. Hoping that is the right move. I will also have the larger top to try, I measured that street top and it’s actually only 173 cubic inches. This motor will be a 418 with 13.3 compression. Wonder if the larger top is better move for my application. I will shift around 6700 but runner length on these are perfect for that
 
Also had this fabricated top I was working on for more runner length but I don’t like how it will negate line of sight. Think I’m shelving that idea for now.

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1bad360duster said:
I’m sure you know on these intakes the top wall curves/pinches down more than the floor. By welding I can match the head port and basically remove that curve and blend it into the top. Hoping that is the right move. I will also have the larger top to try, I measured that street top and it’s actually only 173 cubic inches. This motor will be a 418 with 13.3 compression. Wonder if the larger top is better move for my application. I will shift around 6700 but runner length on these are perfect for that
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The only way to know for sure is to test it.

As a general rule, those big bread box tops were used because about the biggest carb you could get back then was not much over 625 CFM. The bigger plenum wants smaller carbs.

As carbs got bigger, the plenum volume went down, within reason.

The other issue is on the dyno the engine will want more and more and more plenum volume and it will keep making more power. The problem is you will hit a point where even though you made more power on the dyno, the car is slower at the track.

So getting a good balance of plenum volume and carb size requires some dyno testing and then verifying that at the track.

And I suspect that is so because of the way a water brake dyno measures torque. The dyno allows the engine to RPM at a constant rate, whatever that is. Some use 300 rpm/sec, some use 600 rpm/sec and others use multiple rates on the engine. But whatever that rate is, it’s probably not going to be the rpm acceleration the engine sees in the car at the track.

I have somewhere copies of dyno testing between a water brake dyno and an inertia dyno. The results were what looked good on the WB looked bad on the inertia dyno, and what looked bad on the WB looked good on the inertia dyno. Both were crank dyno’s.

The upshot is in the car, the manifold that was the best on the WB was slowest in the car and the manifold that was the best on the inertia dyno was fastest in the car.

In fact, the curves were the exact inverse of each other.

That doesn’t mean the WB dyno is useless or inaccurate. It just means as end users we have to know the limits of the tools we use.
 
1bad360duster said:
Also had this fabricated top I was working on for more runner length but I don’t like how it will negate line of sight. Think I’m shelving that idea for now.

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You may want to keep working on that. I agree line of sight is always the best policy, but getting the fuel/air out of the bottom of the carb and keeping it straight for a bit longer may not be a bad thing.

As you know, any change in section (area) causes a local pressure change. That can really hurt atomization.

Just something to think about as that top may not be a bad thing.
 
Newbomb Turk said:
You may want to keep working on that. I agree line of sight is always the best policy, but getting the fuel/air out of the bottom of the carb and keeping it straight for a bit longer may not be a bad thing.

As you know, any change in section (area) causes a local pressure change. That can really hurt atomization.

Just something to think about as that top may not be a bad thing.
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My main concern was that the air fuel on that outside wall would want to continue straight down and cause turbulence. On the upside that extra length would really boost the torque 5000-6000 and help the car accelerate. I guess it’s always an option.
 
I found a another old picture of my 73 dart. It had a stock stroke 440 and on 93 pump gas ran 10.50 at 126 in the 1/4 at a race Weight of 3450 pounds .
I bought a brand new weieand tunnelram for my 360 magnum 96 Dakota race truck

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Another picture I found of my old 1965 plymouth B-Body race car. 440 with m1 tunnel ram with 2 750 Edeblrock carbs. Best pass of 10.50 at 126 in the 1/4

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