440 tunnel ram

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I meant to disconnect the vacuum secondary actuatin link or temporarily block the vacuum port to them. I suggest doing that unless you have a single four barrel top for the tunnel ram. Four primaries at once would be like having a double pumper with four corner idle adjustment but split across the plenum. Fuel distribution would probably get really sloppy feeding from one end or another on the opposite end on a T ram. But I think that much vacuum signal to the carbs and the light springs are causing the bog. The secondaries are opening like a light switch and the vacuum is falling out past the point of pulling fuel until half track when the revs finally come back up.
 
Garrett Ellison said:
I meant to disconnect the vacuum secondary actuatin link or temporarily block the vacuum port to them. I suggest doing that unless you have a single four barrel top for the tunnel ram. Four primaries at once would be like having a double pumper with four corner idle adjustment but split across the plenum. Fuel distribution would probably get really sloppy feeding from one end or another on the opposite end on a T ram. But I think that much vacuum signal to the carbs and the light springs are causing the bog. The secondaries are opening like a light switch and the vacuum is falling out past the point of pulling fuel until half track when the revs finally come back up.
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I do have heavy springs that open vaccums later would that help
 
Or, you could sell both pairs of carbs and put that money towards two real carbs.

The vacuum secondary carbs are just not worth the effort, as most likely you'll never get the secondaries all the way open with the lightest spring in the vacuum cans.

The 4224 carb is designed and calibrated for 1970's junk. They are worth lists of money to the vintage crowd. They are essentially useless today. They weren't much better back then. Find a sucker for old stuff and stick those up his but for big money. Hell, Holley doesn't even make those any more.

For all the mental masturbation over the carbs you have, you could be done now.
 
Your MPH indicates your engine is making approximately 102 flywheel horsepower. I would forget your carbs and intake, and start with the basics, firing order, leakdown test, ect.
 
Oldiron440 said:
I think the tunnel rams killing it, as in " bogg's half the track"
The last thing a 200 hp motor needs is two 4v carbs and a tunnel ram.
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The last thing a 200 hp smog 440 needs is 2 4v carbs and a tunnel ram. And it doesn't matter what 4v carbs you buy it's a wast of money until you fix the 440.
 
replicaracer43 said:
Your MPH indicates your engine is making approximately 102 flywheel horsepower. I would forget your carbs and intake, and start with the basics, firing order, leakdown test, ect.
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I know firing order is correct as original got told 2 diffrent firing orders so worked that out.
Oldiron440 said:
The last thing a 200 hp smog 440 needs is 2 4v carbs and a tunnel ram. And it doesn't matter what 4v carbs you buy it's a wast of money until you fix the 440.
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What do you mean by a smog 440.sorry for all silly questions new to old mopar stuff
 
What do you mean by a smog 440.sorry for all silly questions new to old mopar stuff.


The numbers on your block say its low compression smog motor, like as in below 8.0 to 1 more like 7.5 to 1. These made for poor performance builds, a small cam is all they will take anything else just slow them down. It's the same with your tunnel ram. Earlier I had said the best thing you could do for this motor is a stroker kit and replace the cast crank and pistons, this will give you much needed compression and even with stockish heads 450 to 475 hp with 550 ftlb of torque. Then your tunnel ram will work for you and if you put heads on it another 100 hp. You desperately need compression and a refresh on the motor before you blow it up.
Good luck
 
Emissions controlled engine. But with its relatively long D port runners and moderately sized funneled plenums the Weiand hi ram isn’t the torque killer that most other tunnel rams are known to be. Agreed that it still isn’t the best choice for a low compression stock cam engine. The light vehicle weight, 3.73 gears, and three speed automatic transmission is going to reduce the negative effects. It’s the carbs that are killing it. What does the time slip say the eighth mile time is vs the quarter mile time? Having the engine stumbling and bogging to the eighth is masking the mechanicals. Usually, the optimum carbs on a 440 with standard intake port window heads is a pair of competition type 750 cfm double pumpers pre tuned to a dual carb application.
 
And here is where the trouble starts. If your race weight is 2200 pounds, you only need 450 hp to run 10s. Instead of buying aluminum heads and cam, you could rebuild the 440 with a reverse dome pistons set for 10:1 with .035 quench, mildly worked 452 heads with three angle valve job, a single four barrel, and a good hydraulic cam. If it were me, I would be looking at an aluminum head 340 or 360 build. Taking a 100 plus pounds off the front end would be a sizable performance improvement in itself. Want to be really different? Turbo slant six!
 
Garrett Ellison said:
And here is where the trouble starts. If your race weight is 2200 pounds, you only need 450 hp to run 10s. Instead of buying aluminum heads and cam, you could rebuild the 440 with a reverse dome pistons set for 10:1 with .035 quench, mildly worked 452 heads with three angle valve job, a single four barrel, and a good hydraulic cam. If it were me, I would be looking at an aluminum head 340 or 360 build. Taking a 100 plus pounds off the front end would be a sizable performance improvement in itself. Want to be really different? Turbo slant six!
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The problem with mopar is if you swap engine family you swap transmissions and start over completely. A rebuild with decent parts will blow past 450 hp and more torque than a small block and will be able to use transmission that is in place. I would imagine that parts arnt the easiest thing to come up with in the UK.
 
Oldiron440 said:
The problem with mopar is if you swap engine family you swap transmissions and start over completely. A rebuild with decent parts will blow past 450 hp and more torque than a small block and will be able to use transmission that is in place. I would imagine that parts arnt the easiest thing to come up with in the UK.
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Very hard yo come by all parts i have had ive imported
 
Garrett Ellison said:
Emissions controlled engine. But with its relatively long D port runners and moderately sized funneled plenums the Weiand hi ram isn’t the torque killer that most other tunnel rams are known to be. Agreed that it still isn’t the best choice for a low compression stock cam engine. The light vehicle weight, 3.73 gears, and three speed automatic transmission is going to reduce the negative effects. It’s the carbs that are killing it. What does the time slip say the eighth mile time is vs the quarter mile time? Having the engine stumbling and bogging to the eighth is masking the mechanicals. Usually, the optimum carbs on a 440 with standard intake port window heads is a pair of competition type 750 cfm double pumpers pre tuned to a dual carb application.
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1/8 et 10.39 speed 57.81
1/4 et 16.18 speed 82.71
 
One possible advantage is that Jensen interceptors used a 440 RB engine so you may have access to parts in stock within the UK still. But definitely time for freshening up the bottom end. I imagine even when it does start to pull after recovering from the endless bog, it's pretty anemic. Admittedly, I do like the idea of a stroker. One of the 4.35 inch bore by 3.9 inch crank affairs with reconditioned rods could probably make use of some off the shelf low compression cast pistons.
 
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Garrett Ellison said:
One possible advantage is that Jensen interceptors used a 440 RB engine so you may have access to parts in stock within the UK still. But definitely time for freshening up the bottom end. I imagine even when it does start to pull after recovering from the endless bog, it's pretty anemic. Admittedly, I do like the idea of a stroker. One of the 4.35 inch bore by 3.9 inch crank affairs with reconditioned rods could probably make use of some off the shelf low compression cast pistons.
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Jenson parts are just as rare here and are at a premiun
 
The cylinders being within 10% of one another is twice the acceptable limit for a compression test. But that thing is running like the nylon aluminum cam sprocket has more smooth than teeth and the camshaft resembles a piece of round bar stock. I really hate it because of the unplanned expense of a rebuild, but it’s really necessary at this point.
 
Jadaharabi said:
Before I would rebuild it, I would pull the front cover and check the gears and cam timing.
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Finally got round to pulling front covee to look at gears looks like chain is very loose. How do you check cam timing

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