Victor, Super Victor...or just stick with my LD 340 maniflold

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Cudafever

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Now that i have traded my 3000 stall converter for a 4200 stall converter. Wondering if it would be worth it to step up......or am i wasting my time and money???

So here is the spec's
408 stroker,
12.8 compression
Hyd Roller .563/.555 lift 243/247 @.050
RHS Iron Heads that flow 270 cfm
4200 stall converter
Shift at 5800-6000 RPM
LD 340 manifold with divider ground out and flange ground out for a TQ that i use to run on
this manifold
ProForm 850 double pumper.
OH! and one more Factor. Most of my racing it at 6600 foot elevation.

Keep LD 340 Dual Plain manifold or, run a single plain manifold...?...?.........

EDIT more info requested.
curb weight is 3860 with me in it. "heavy race car"
727 transmission
4:56 rear gear with a 28-10.5-15 M/T slicks
 
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strickly race or street strip? I don't see a super victor at all either way, maybe a victor or other maybe would be small gain imo if race only, just not turning alot of rpm
 
that's what the Victor was designed for, and you can probably recoup the cost on a used one by selling the LD340 on here... You might also consider the Mopar M1 single plane that is designed for race only use (doesn't even have a place to run heater hoses).
 
i don't think you would see much gain from it if any imo and damn 6600 a really really bad air day for us is like 4000da
 
a good "air day" is 7500 da. a bad day is 9800da

I feel like i have enough head flow, but wonder if my intake is restricting me. Not enough cross sectional area............then i factor in the rpm and DA and wonder if it's a waste of time.
 
a good "air day" is 7500 da. a bad day is 9800da

I feel like i have enough head flow, but wonder if my intake is restricting me. Not enough cross sectional area............then i factor in the rpm and DA and wonder if it's a waste of time.


Victor hands down. Maybe a Strip Dominator if you can find one.

At your displacement the LD is choking the engine. It wasn’t designed for that many inches.
 
I like the Victor in this set up.
Port match it and up the runner as far as you can go.

Thanks for that.:thumbsup:
That's what started my thinking and caused this thread.
If i was turning 6500+ it would be a no brainier......but at 5800 rpm........................
 
Victor 340 will do the trick! I have a milder set up used to run an airgap. My 360 only has a 292/508 mopar cam. 3.91's out back. Switched to Victor 340 and gained power everywhere over the airgap! This is only a street car. Dodge dart sport 360.
 
Hi, does anyone know what the height difference is between the Victor and the LD340?
 
I have a love affair going with the Victor 349 intake as I’ve seen what it can do with a little port work. Not sure you have ever read the post I did on an LD340 that I ported and did some flowbench testing for a friend. That intake although not good kinda shocked me some on how well
It did flow. I’m not sure which one I would recommend at your weight and altitude but for sure it wouldn’t be a Super Victor. I always kinda bad mouth that intake I guess because I know how bad it was out of the box but I did end up running 9.73@135mph with one and I haven’t hated it bad enough to part with t.
 
Now that i have traded my 3000 stall converter for a 4200 stall converter.

So here is the spec's
408 stroker,
12.8 compression
Hyd Roller .563/.555 lift 243/247 @.050
RHS Iron Heads that flow 270 cfm
4200 stall converter
Shift at 5800-6000 RPM
LD 340 manifold with divider ground out and flange ground out for a TQ that i use to run on
this manifold
ProForm 850 double pumper.
Thanks for that.:thumbsup:
That's what started my thinking and caused this thread.
If i was turning 6500+ it would be a no brainier......but at 5800 rpm........................
The cam is large enough, but yet still what I call, boarder line-ish, in size, (if not slightly under that line I have in my head) that the intake choice can be ether intake manifold style. The dual plane will offer more torque down low while the single plane offers better top end rpm power in the typical like fashion we basically know of. It just all comes down to what your doing and the goal.

Since you have a new converter with a higher stall in what I am assuming is more of a race car, you are ignoring the low rpm power to get into the meat of the power at a higher rpm. This is for sure going to help the car.

(I don’t know the cars gear ratio or tire size, but I’ll assume it is more so for the strip.)

The only draw back right now is the overall weight of the car which makes me a little nervous on how well the actual gain might be. I’m really more with @scampy. It may be close to a wash.

Looking forward to the slip report.
 
The cam is large enough, but yet still what I call, boarder line-ish, in size, (if not slightly under that line I have in my head) that the intake choice can be ether intake manifold style. The dual plane will offer more torque down low while the single plane offers better top end rpm power in the typical like fashion we basically know of. It just all comes down to what your doing and the goal.

Since you have a new converter with a higher stall in what I am assuming is more of a race car, you are ignoring the low rpm power to get into the meat of the power at a higher rpm. This is for sure going to help the car.

(I don’t know the cars gear ratio or tire size, but I’ll assume it is more so for the strip.)

The only draw back right now is the overall weight of the car which makes me a little nervous on how well the actual gain might be. I’m really more with @scampy. It may be close to a wash.

Looking forward to the slip report.
Updated data on first post

Ignore the RPM thing.
It's hard to ignore rpm when every manifold description tells you what rpm it work best in.
 
Updated data on first post


It's hard to ignore rpm when every manifold description tells you what rpm it work best in.


Yeah, when you dyno a bunch of them and learn that is a guesstimate at best, you stop worrying about it.

I have asked a million times, but I’ll ask it again.

When is making a column of air and fuel turn a corner good?

Answer: NEVER.

Yet the dual plane is claimed to make more power down low (it doesn't) while making the same power at whatever RPM the marketing department is aiming at.

The OEM’s used them because they worked to a different criteria than what you want. That’s why they used hot exhaust under the carb. It’s a power loser, but they did it because they weren’t trying to make power.

Air flow is air flow. It follows physics. Unless you have to do it, or you have a reason for it, you never make air turn a corner.
 
The dual plane vs single plane is very true but has its limitations that the aftermarket simply describes as the operating rpm band in which they work in. It isn’t false, but it is a rule that can be bent and sometimes real easy, as in your case, the use of an dual plane intake designed a very long time ago for an engine that is an easy 48 to 68 cubic inches smaller.

This is why YR said to ignore the rpm thing. Your pulling more air and fuel in per cylinder stroke at a much greater rate than the OE sized engines.

The dual planes help torque production due to its long runners. This is why tunnel rams owners love there intakes. Ask around, you’ll see. The bends in the runners do not help anything but hood clearance.

Is this a Dedicated race car?
The car is super heavy for an A body race car. It could really use a 500lbs. diet.
 
I get what your saying 100%
but now let me throw a couple more thoughts your way.
reversion......."at low rpm" it will do a better job of canceling it right........over a single plan.

The 2n't one is the one that is really on my mind.
You know all the problem i have had with to big of a carb and stumble(for the most part is fixed.) OK here is the question.

I feel like if the minimal cross section of the intake track, is the intake manifold, and the problems i have been having is to weak of a signal to the carb as the throttle is slammed open....................would not the signal to the car be quicker with out the restriction????? or is it the opposite and a smaller manifold would send the signal to the carb faster...........

thats my 2nt questioning as to if a single would be a better or worse move.................
 
The dual plane vs single plane is very true but has its limitations that the aftermarket simply describes as the operating rpm band in which they work in. It isn’t false, but it is a rule that can be bent and sometimes real easy, as in your case, the use of an dual plane intake designed a very long time ago for an engine that is an easy 48 to 68 cubic inches smaller.

This is why YR said to ignore the rpm thing. Your pulling more air and fuel in per cylinder stroke at a much greater rate than the OE sized engines.

The dual planes help torque production due to its long runners. This is why tunnel rams owners love there intakes. Ask around, you’ll see. The bends in the runners do not help anything but hood clearance.

Is this a Dedicated race car?
The car is super heavy for an A body race car. It could really use a 500lbs. diet.

I my be a little over weight but not that much:lol:
It's a complete E Body that only goes to the race track. no street time.
 
I get what your saying 100%
but now let me throw a couple more thoughts your way.
reversion......."at low rpm" it will do a better job of canceling it right........over a single plan.

The 2n't one is the one that is really on my mind.
You know all the problem i have had with to big of a carb and stumble(for the most part is fixed.) OK here is the question.

I feel like if the minimal cross section of the intake track, is the intake manifold, and the problems i have been having is to weak of a signal to the carb as the throttle is slammed open....................would not the signal to the car be quicker with out the restriction????? or is it the opposite and a smaller manifold would send the signal to the carb faster...........

thats my 2nt questioning as to if a single would be a better or worse move.................
I think you should ditch that Ol dual plane manifold a donate to some poor old cripple Guy who would pay for the freight. PM me if you would like my shipping address. LOL
 
I get what your saying 100%
but now let me throw a couple more thoughts your way.
reversion......."at low rpm" it will do a better job of canceling it right........over a single plan.

The 2n't one is the one that is really on my mind.
You know all the problem i have had with to big of a carb and stumble(for the most part is fixed.) OK here is the question.

I feel like if the minimal cross section of the intake track, is the intake manifold, and the problems i have been having is to weak of a signal to the carb as the throttle is slammed open....................would not the signal to the car be quicker with out the restriction????? or is it the opposite and a smaller manifold would send the signal to the carb faster...........

thats my 2nt questioning as to if a single would be a better or worse move.................


Using the intake manifold to control reversion is a power killer.

You start controlling reversion with the valve job and port work.

You reduce reversion buy using the correct cam timing, and not using a lobe from the 1970’s. A quicker lobe will almost always make more power, but it comes with a price. Due diligence on break in, oil use, idle speed and idle time all become more important as the lobe gets quicker.

If you really think you are having reversion issues, there are spacers that can help with it, but none of the probably 20 I have tested look like what most people use.

If the anti-reversion spacer you are looking at will bolt to the manifold without modifications to the manifold, it won’t do anything for reversion.

It may make more power because the plenum needed more volume, but they don’t do anything to reduce reversion. This is similar to a spacer I tested in 2007. I can’t remember the exact manufacture of what the customer brought in, but it looked exactly like this. I forget how much more power it made, but we know it helped with reversion by the A/F numbers and the jet sizes we dropped. https://www.visnerengine.com/thrott...ers/4500-1-extended-7-degree-shear-plate.html

Here is one I may try next spring when I go to the dyno. It depends on how much more work I want to do and how much effort I want to put into testing. None of these are cheap. I’m not sure the damBest spacer is bolt on because I’ve never had one in my hands.
Carb Spacer, 4500 2.125" Sportsman Combo, dAMBEST Carburetor
 
Once you make your decision, you might want to experiment with different thickness carb spacers. Just FYI, I ended up with a Strip Dominator with a 2 " Super Sucker on my 416. I really like the mid to top end response, I shift @ 64-6500 RPM & I go through the traps @ 65-6600 RPM.
 
I get what your saying 100%
but now let me throw a couple more thoughts your way.
reversion......."at low rpm" it will do a better job of canceling it right........over a single plan.

The 2n't one is the one that is really on my mind.
You know all the problem i have had with to big of a carb and stumble(for the most part is fixed.)
Reversion is multi level issue. The amount and how problematic it is will be different for ever engine combo. Overall, I’d say no. The pressure wave will travel just as easy up a straight line as a turning one.
IMO, that issue you were having, my own answer was a smaller carb and/or more stall, less car weight, ignition and/or cam timing, the list can be long. I can’t really answer it because I can’t put my hands on it as well as not so familiar with your build and lack of experience with having that issue myself.
I wish I could help there but I’m not able to.
Believe me! If I could I would!
OK here is the question.

I feel like if the minimal cross section of the intake track, is the intake manifold, and the problems i have been having is to weak of a signal to the carb as the throttle is slammed open....................would not the signal to the car be quicker with out the restriction????? or is it the opposite and a smaller manifold would send the signal to the carb faster...........

thats my 2nt questioning as to if a single would be a better or worse move.................

A smaller runner intake manifold should be providing a stronger single and quicker velocity through the runner. I can not prove this and even if so, this may not pan out the way you think it would. There is also one other issue to this puzzle, plenum volume. All of these things are more often a small part in the overall Luther of how well an engine performs in the way you want it to or the way the engine will.

A good example (IMO) is the small block TrokerII-340. Short thin runners with a large box plenum. Often used in the street with to mild or a cam and gear. This intake is actually best used (again, IMO) with a cam larger than 250@050 and more stall than you would normally use it. A street car with drag parts.

The reversion issue I don’t pay attention to in a large way. It is a problem at low rpm, idle to ..... all under the power curve you are really paying attention to.

Again, IMO, if your car is idling to ratty for a decent idle and low speed driving, it’s the wrong cam and probably on a to low center line. (Narrow LSA)

Once your engine starts spinning some rpm, the reversion issue starts to disappear and rapidly.

Cross sectional area..... A port matched intake should perform the best. If the runner is smaller than the heads port, it is possible that it may under perform, but, only if the engine demand needs that max area. (Or said easier) A smaller runner may, reduce power unless the engine needs the larger runner. The reverse is possible, but rather unlikely.

I my be a little over weight but not that much:lol:
It's a complete E Body that only goes to the race track. no street time.
Ahhhhhh, I see. My ‘73/4spd is lighter. It has a little help... missing parts and a fiberglass hood. Though the 6pack added some weight back...

I think you should ditch that Ol dual plane manifold a donate to some poor old cripple Guy who would pay for the freight. PM me if you would like my shipping address. LOL
ROFLMAO!!!
 
Now that i have traded my 3000 stall converter for a 4200 stall converter. Wondering if it would be worth it to step up......or am i wasting my time and money???

So here is the spec's
408 stroker,
12.8 compression
Hyd Roller .563/.555 lift 243/247 @.050
RHS Iron Heads that flow 270 cfm
4200 stall converter
Shift at 5800-6000 RPM
LD 340 manifold with divider ground out and flange ground out for a TQ that i use to run on
this manifold
ProForm 850 double pumper.
OH! and one more Factor. Most of my racing it at 6600 foot elevation.

Keep LD 340 Dual Plain manifold or, run a single plain manifold...?...?.........

EDIT more info requested.
curb weight is 3860 with me in it. "heavy race car"
727 transmission
4:56 rear gear with a 28-10.5-15 M/T slicks
Why does one remove the plenum divider? I have seen this before and always questioned it, one manifold that I had years ago had a bid square notch cut out of it?
 
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