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Discussion Starter · #1 ·
I was reading "the Chevrolet racing engine" by Bill Jenkins I know this is a 33 year old book and that lots have changed in the last 33 years. I was interested in what he was saying about tunnel rams and stuffing blocks used between the carbs in the manifold base to reduce fuel puddling. What would happen if you raised the "stuffing block" to make the front carb only feed the front four cylinder and the back carb feed the back four. I understand this would kill the plenum volume, but increase the signal to the carb. What would the effect be on hp and TQ???
 

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Your theory is good but im not sure if it would work. The ideal venture length is over a foot long. Thats why 4 hole spacers work so well. Look what the pro stockers run now. Split carbs that sit over the intake valves to basically run straight tubes to the valve, and i bet they run each venturi to each cylinder so they can tune each cylinder accordingly. Kind of like the old hilborn setup. They only thing you can do is try it.
 

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i have that book too

i have that book too.

I put a tunnel ram on a street motor , 355 9.5-1 , double humps , 284 crane energizer cam , fenderwell headers , weiand tunnel ram with 2 450 mechanical carbs, 2800 stall with 411 gears . It was not short on bottom end at all , in fact it boosted it. It really surprised me how well it helped the bottom end power after all ya hear about tunnel rams.

What it did do was drink gas like you were pouring it out on the ground and foul plugs , but , it was a rush when it was running right. I got it in a trade so i didn't have that much in it. Maybe an upgraded ignition might have helped like a MSD-7 or something of that nature.

I didn't mess with it too much before i put the tarantula intake ( TM1 ) and 650 dp back on. It might have had a blown power valve or something but the gas it used was just crazy so i took it off.
 

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Engine building Guru " Joe Sherman" will tell you that a Tunnel Ram with 2-properly preped carbs will make 100+ HP over a single intake and carb setup.
He's been doing it since the late 60's.

I've had tunnel rammed street strip engines that where set up correctly, and they ran like raped-apes.
 

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Engine building Guru " Joe Sherman" will tell you that a Tunnel Ram with 2-properly preped carbs will make 100+ HP over a single intake and carb setup.
He's been doing it since the late 60's.

I've had tunnel rammed street strip engines that where set up correctly, and they ran like raped-apes.
Very very true!!!!


Al
 

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a Tunnel Ram with 2-properly preped carbs will make 100+ HP over a single intake and carb setup
But the average guy running a tunnel ram throws a couple Edelbrocks on top and never comes close to the power a single carb would make!
Steve Dulcich makes them work great with Mopar engines on the dyno, but I don't know of any cars ever running one of them--it's hard to drive a dyno!!
I've only known one guy that ran one on the street, and was actually fast--it was an El Camino with a 406 and Edelbrock Street Tunnel Ram w/2-750 Holley's. Deep 10's with a small shot hidden under the manifold.
 

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you can't beat tunnel rams for the power they give vs a single carb. I ran a pro dom tunnel ram on my 406 and it was unreal. For street driving IMO the key is having progressive linkage so the primaries are only being used till WOT. I think thats why they had the small 450 vac sec carbs for tunnel rams.

Here is a pic of my motor with the tunnel ram and 2 660's

 

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Discussion Starter · #8 ·
I have toyed with the idea for a few years on using the eddy set up. Will I who knows, I'm just looking for some theory. I'd love to build a screaming 327 Tunnel ram for the gasser, after I get tired of the current 327 I have for it.
 

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Discussion Starter · #9 ·
The Wieand tunnel rams have a removable to that looks like you could build a adapter to mount two four barrel cabs and feed the front four and back four with tier own carbs, say bolt a 2" spacer on top the base to give it some plenum volume, am I thinking WAY out of the box or is tis something that could be practical???
 

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I found a "old" pic! this is when I ran B/GAS this is 1984?
277cu Nash 5 Speed
I used the Holley Dominator intake, 660 carbs.

Al
 

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How well did it work???
I run under the index!
This was a WOT only setup.
RPM was 10,600

Wind it up and let it go!

I wish everyone could feel this once in there life!
When you let the clutch go "BAM"



Al
 
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