Mopar 69-74 Pro-Stock Hemi Dominator 2 x 4 IR set up?

xctasy

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Ford's Bud Moore 302 Trans Am Boss Dual Quad Independent Runner 3 circuit intakes found,


what about Chrysler 1969 to 1974 Pro-Stock Hemi Dominator 2 x 4 IR set up?


I've seen in line AFB and Holley 4150 low risers, but not an IR Pro Stock Dominator dual quad. Anyone got picks.

My efforts have been fruitless elsewhere.

http://www.460ford.com/forum/showthread.php?t=159130

After this stuff, I just had to go look-up my old paperwork from Chrysler Racing.
Here's the deal ... when the L6464 I.R. was released in 1969 for Ford 302 Trans-Am, dual 4 barrel I.R. engines there was no 1150 Dominator main body casting. When the 1150 casting was introduced 8 months later, (when Chrysler Pro-Stock Hemi's began using them), as a L7320 & L6214 the L6464 was then relegated to be a MINI-plenum carb and now being produced with the shorter, larger bar boosters replacing the longer, smaller bar boosters which were now being used exclusively in the L6214 carbs as the new I.R. carburetors.

EDIT: So, the L6464 carbs only had the I.R. boosters for 8 months of production.

And http://www.randyayersmodeling.com/model ... e67d51a53b have been my best initial searches
 
Now for the math. This does relate to an IR Holley 6-bbl manifold I'm using on my variable capacity log headed 3.3/3.6/4.1 Mustang

VenturiSizeInmmforIndepentRunnerCar.jpg


A 200 Falcon six with three #7448 or 9117 350 cfm carbs needs a cam whch provides power at below 5000 rpm, possibly 4800 rpm. (30.2 mm venturi and 544.9 cc's. based on a below 5000 rpm curve)
A 221 Falcon six with three #7448 or 9117 350 cfm carbs needs a cam whch provides power to 4200 rpm. (30.2 mm venturi and 603.1 cc's based on a below 5000 rpm curve)
A 250 Falcon six with three #7448 or 9117 350 cfm carbs should only need a cam which provides power to 3500 rpm to run in an optimized manner. (30.2 mm and 681.5 cc's based on a below 4000 rpm curve)

A 250 Falcon with a three #4412 500 carbs needs a cam which provides peak power at 5000 rpm.(34.9 mm venturi and 681.5 cc's based on a 5000 rpm curve)

http://victorylibrary.com/mopar/intake-tech-c.htm#ir
IR manifolds, where each cylinder can only draw from one barrel, offer the absolute best idle quality, throttle response, tolerance of high-overlap cams timing, and allow accurate tuning of intake length for maximum torque.
Even using the largest common IR carburetors (Weber 48mm IDA with 45 mm venturis) the maximum cylinder size is about 45” (or 70 HP, whichever is less) barely enough to supply a 360” motor @ 7000 RPM
Completely separated IR carburetors for a 500” motor (62.5” cylinders) @ 10,000 RPM would require 63mm(2.47”) venturis!
 
I'm confused.

You're posting pictures of SBF trans-am dual dominator induction systems, and Chrysler tunnel ram photos asking for pics, and doling out info about them on a website where the core concern of most of the participants here are trying to get their engines to idle more smoothly? :unsure:

They don't even offer a comment about a street/race version of one of their own engines,...Looking at one of the trans am pics you posted was just 7 extra venturies, and 102 cubic inches more than 90% here will ever know ( or care to know) about. :nono:
 
mike1157":h502c5lb said:
I'm confused.

You're posting pictures of SBF trans-am dual dominator induction systems, and Chrysler tunnel ram photos asking for pics, and doling out info about them on a website where the core concern of most of the participants here are trying to get their engines to idle more smoothly? :unsure:

They don't even offer a comment about a street/race version of one of their own engines,...Looking at one of the trans am pics you posted was just 7 extra venturies, and 102 cubic inches more than 90% here will ever know ( or care to know) about. :nono:

Any time he does this stuff, he is sutdying and learning like most of us here.
Its not often, and It doesn't bother me.
 
Just think of these posts as footnotes to a larger opus. Xtacy is one of our resident geniuses. And like all great minds, his intellect is just a few degrees north of dangerous.

BTW, that tower intake is supposed to make enough torque to twist a Ford 9" out of a Mack truck when mounted on a Mopar hemi.

I'd love to see something like that for a log head.
 
Bike carbs, Deano. Bike carbs.....

Tuning was always an issue, but I think we cracked it on this one. Main jets drilled to 205, pilot jets drilled to 42.

This one pulls like a freight train, idles rock steady at 1000 rpm. No bog, no holes, and gets 25+mpg (US gallons).

Or put together a six pack of the Honda CBR EFI throttle bodies with a Megasquirt.
 

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Yours, Jack?

I guess the long throats do the same thing as that tower intake manifold.
 
Oh, I'm with you Jack, I love American Mikunis in every area, especially quality, its Japanese ancestry ( you know I love the Japs, especially Honda and Keihin), but I don't want side draft carbs. They don't work with the X shell body, not in regards to non cross flow heat soak, and regards their inabilty to work with turbos and F150 4.9 style architecture I've been heading to with my Fazer engines, its a non starter. I have looked at high mount Mikuni sixes, a variation like what Paul Knott used with his DCOE 45 170 Falcon with its Jag XJ 12/ X-flow EFI 4.1 style intake, but its not as easy to get that to package as a short runner engine. I loved Ak Millar's early Horsing around with the Mustang six article.

If I could get the unit rate down enough, the Aisan Variable Venturi carb would be reworked in ceramic or henium coating and I'd rob every Tercel or Proton of its VV carb, but the Malaysians don't have a second hand part industry, and the new Toyota, used or recon US carbs or any of those the world over are more expensive than Mikunis.

The Holley 2-bbl can be reworked, just like the triple circuit 4500 series carb, which makes real power, and there are 2300 carbs everywhere. Its the idle control circuit that I've got sussed, and that is the problem, when any individual throttle system is used, it suffers from throttle balance issues over time. The Holley 2-bbl is the best bet, and its the right size, everytime.


Back to where I was.
 
Hey Xctasy, You are one smart dude. I'm curious what you're working on, if you can talk about it. If not, that's okay too. Looks like a specific torque curve or flow rate in comparison to RPM. But, I don't understand the math.
 
Guys. II know the 390 hp 3 liter Argentine I6's don't idle well, but most independent runner systems do. My favorite account was the 1995 Holden v8 engined Vee Eight SuperCar with slide throttle EFI that idled at 600 rpm from a five liter V8 which made 560 hp at 7500 rpm. You can have both!


Aussie7mains had an independent runner 221 2V 250 headed engine with DCOE45's and smaller than 40 mm venturis, and it had a rock solid idle, he said it was the best feature. How many single carbed 2V's and CI have an unsteady idle or slightly poorer than expected idle. This info is here because with standard multiple Holley 2-bbl carbs sized right, you can have it all. You can use that big cam with more carbs. The mm venturi graph supplied affirms in excess of 1.5 hp per cube depending on engine rpm and engine size.

That's why I link those Dominator 4500 carb engines, because they and the old later inline 4 Autolites used to do the same thing..allow a very highly strung engine with more than 1.5 hp per cube to idle softly when the venturi sizes are optimized to suit cylinder capacity. On the graph, the 4500 Holley 4-bbls were 46.0 mm 1-13/16 for the 1150, and 42.9 mm 1-11/16 for the 1050. Up till now, Americans have sized carb on cfm figures from TransAm to Pro Street to Nascar, but after 1986, everyone else, including F1 and Indy Car went to EFI and 80% duty rating, and the world suddenly was back to independent runner intakes again. The missing link is the point in between single throttle body port EFI, and single 2 and 4-bbl carbs, and that is the lost art of port on port IR carb tuning, an Aero engine Italian Weber idea dating back to pre World War II.

Just like an old slide port on port, independent runner injection D type Lemans Jags in 1957 used to be able to do 180 mph with 2.65 gears, yet idle like a Cadillac with well over 250 hp from 3.8 liters.


The problem is that up until now, everyone has thought better heads, better air flow, bigger carbs. Some where between the hardcore I6 drag racers of the late 70's and the cookie cutter 4-bbl and EFI V8's of today, there is the lost art of Independent runner intakes. And its as American as L/R ratios for conrods, and as conclusive as that research was to making hp. The Aussies with there L6 GM Holdens, the US Mopar Slant Six guys and GM six cylinder HAMBer's are way ahead of us Ford I6 guy's, although the early 70's Maverick Prep H was proof positive that a 390 hp at 7000 rpm engine could be make with just a heavy duty 300 six.

The info is out there, and Americans with roller cammed I6's were doing this kind of stuff in the mid to late 70's.
 
chessterd5":7224xoje said:
Hey Xctasy, You are one smart dude. I'm curious what you're working on, if you can talk about it. If not, that's okay too. Looks like a specific torque curve or flow rate in comparison to RPM. But, I don't understand the math.



I'm not smart. I'm a just a dumb a$$ disciple who follows.If I was a genius, I'd never reveal my information sources, or else people would then become as smart as me. But I am walking you through this stuff again, I'm using past info to perform the up-skilling for you guys, paying it forward, giving you the advantage shot. Its like lost Ionian Greek or Mayan knowledge, but on the internet, its actually you Americans who have used and leveraged the info to its fullest. It started with the Holley 660 Centre Squirter, then the Dominator 4500, and then continued on Mikuni 44mm carbed Baja 2000 cc Pinto engined off road racers, and now Jack has perpetuated it with the Locost 'Jack Collins X' 6 and his sons MG.


The IR/port on port tuning means any 350 or 500 cfm Holley can be matched to the right cam and capacity Ford I-six, and you can then hit specific power ratings equal or better than the 5.0's.


The graph probably needs to be imperilized, and a hp per cube line inscribed so we can use it with out the silly French units, but the line between the 6000 and 8000 rpm one is what the Preparation H 300 Ford six 48 mm, 42 mm choke Webered Big Six engine was based on. With a modern roller cam and perhaps a set of 500 cfm carbs throtles and venturis taken out taken out to to 650 cfm spec +62.5 thou over (1.75" throttle/1.4375"36.5 mm) or even 1.56"/39.6 mm chokes, the maximu a Holley casting can be routed out to easily.

There is total scope with out needing anything more than an intake manifold adapter and some common carbs.


Key is that cylinder head cfm and cylinder size can calculate peak rpm power from the Stan Weiss website http://users.erols.com/srweiss/index.htm

See the massive 131 column by by 21 row "RPM of Peak Horse Power" table and follow below

1) Calculate the cubic inches of one cylinder of your motor.
2) Run across the top column and find the closest value.
3) Take the CFM for the head you are looking at a valve lift that is below maximum valve lift for the cam you are running.
4) Run down that column until the left hand column has the CFM closest to that number.
5) Example 1 and 2 below
Pontiac 400 / 8 = 50 ci per cylinder.
Pontiac i6 Jim Butler has 245 CFM @ .500 lift and 504 hp

Port on port/Independent Runner intakes will give around 100% of the peak flow figure at the lift your cam and head yields.
 
Hello xctasy, I think I'm getting it. The closer you get each individual cylinder to running like it's its own engine, in harmony with each other sharing a common crank, the better the overall performance will be?
Is there a formula for determining proper intake runner length?
If I understood all this right, using a 300 I6 as example: 1) you need the size of the cylinder wich is 50cid or 820 cc. 2) you need the size of the venturi to match cylinder capacity. By your chart above, I'm guessing that to be either 48 or 49 mm wich is 1.89" & 1.92" ( wich is also the suggested size for intake valves on a 300. Chevy 1.96 cut down to 1.90.) 3) You need the lenght & diameter of the intake runner from the carburation to the valve cause technically the intake port in the head IS part of the intake runner. The Preperation H car used 1.75" tubing & the carb horn was 18" away from the valve seat by the article. Does this still hold true now? Or should the diameter of the intake tubing match the size of the venturi as well as the size of the intake valve (about 1.90")? 4) Cam size: cause this affects cylinder capacity, right? & the vacum signal to the carb telling it to "refill" the cylinder, right? & when the intake valve opens & closes? So, what size cam matches (as a baseline) a basicly stock 300, ported to flow lets say 210 cfm & a 6000 rpm limit using the port on port I/R carburation we're discussing. I coundn't find lift & hp #'s on the Stan Weiss site so I can't calculate what 100% of peak flow for cam & heads means. I'm sorry I'm dumb but I'm trying.
 
The Ramchargers Chrysler engineers pioneered the long ram tube length intake runners back in the 50's. They have a formula for determining the optimum runner length for a certain RPM. The one of 18" works out to give its optimum peak RPM at 4666 RPM, which is way too long for the high RPM that those engines turned. Something more around 9"-10" brings it down more where it should be for 8000 RPM+ where that engine ran.
Here's their formula: N x L=84,000, N=desired engine RPM, L=length from the valve head to ram tube entry, and 84,000 is a constant.
 
CNC-Dude":243js13f said:
The Ramchargers Chrysler engineers pioneered the long ram tube length intake runners back in the 50's. They have a formula for determining the optimum runner length for a certain RPM. The one of 18" works out to give its optimum peak RPM at 4666 RPM, which is way too long for the high RPM that those engines turned. Something more around 9"-10" brings it down more where it should be for 8000 RPM+ where that engine ran.
Here's their formula: N x L=84,000, N=desired engine RPM, L=length from the valve head to ram tube entry, and 84,000 is a constant.


Check it out, I think this is it. https://images.search.yahoo.com/images/ ... =yfp-t-901
 
chessterd5":3s6wbsql said:
Hello xctasy, I think I'm getting it. The closer you get each individual cylinder to running like it's its own engine, in harmony with each other sharing a common crank, the better the overall performance will be?
Is there a formula for determining proper intake runner length?
If I understood all this right, using a 300 I6 as example:

1) you need the size of the cylinder which is 50cid or 820 cc.

2) you need the size of the venturi to match cylinder capacity. By your chart above, I'm guessing that to be either 48 or 49 mm which is 1.89" & 1.92" ( which is also the suggested size for intake valves on a 300. Chevy 1.96 cut down to 1.90.)

3) You need the length & diameter of the intake runner from the carburation to the valve cause technically the intake port in the head IS part of the intake runner. The Preperation H car used 1.75" tubing & the carb horn was 18" away from the valve seat by the article. Does this still hold true now? Or should the diameter of the intake tubing match the size of the venturi as well as the size of the intake valve (about 1.90")?

4) Cam size: cause this affects cylinder capacity, right? & the vacuum signal to the carb telling it to "refill" the cylinder, right? & when the intake valve opens & closes?

So, what size cam matches (as a baseline) a basically stock 300, ported to flow lets say 210 cfm & a 6000 rpm limit using the port on port I/R carburation we're discussing.

I couldn't find lift & hp #'s on the Stan Weiss site so I can't calculate what 100% of peak flow for cam & heads means. I'm sorry I'm dumb but I'm trying.
Item 1 and 2 are bang on...that is it totally, nothing else. The line for 6000, 7000 and 8000 rpm is a function of the volumetric efficiency line from Stan Weiss site
Last notes on cam, Item 4, is partly the cfm at max lift, but isn't needed, as item 3 4, and the last concern over cam governs that peak power rpm anyway.

See http://users.erols.com/srweiss/tablehdp.htm for

Cylinder Head Flow Data at 28 Inches of Water

How to use the RPM of Peak Horse power Table.

All those important questions you raised are non matters for the graph, only item 1 and 2 are. The curves won't be made if the cam and carb aren't right for that selected venturi and cylinder capacity. It then tells you the rpm range at maximum power, and what reults will work, even if you had the wrong sized intake runner volumes, cross sectional area and carb entry distance. They are minor matters. As I state later, our Falcon 250's from 1971 log, to 1971 2v non cross flow, to 1976-1980 iron cross flow to 1981-1992 cross flow varied 25% in size and 50% in runner length, with the last heads being smaller in runner than the 2V 250 head, yet yielding better flow. So a 2-bbl direct log, 2v 250, iron x flow and alloy x-flow with the same 2-bbl carb all yield the same 149 flywheel hp at 3800 rpm with the same cam and single tube header exhast. In a 3000 pound car with a four speed and 2.92 diff, 16.9 seconds for a quarter mile comes up irrespective of the intake manifolding, weather an 1972 XY Falcon GS or a 1982 XE Falcon GL...the intake geometrics are not a major factor.


This is why I don't ever get into carb entry distance (Ced),volume of intake (Vi, cross section and length based) and Cross sectional area (Xa, cross section and length based) because you first have to build an independent runner system to fit the engine and engine bay, and hood limitations means you can't run the optimum lengths in any direction. Just like tube headers, its what fits, not what the formula recommends, a very important engineering principal. The Pipe Max program gives you 1st to 8th harmonic optimizations, with the 3rd order ones often the best. Pipe Max covers off a little of what the RamChargers found, but Amal carbs found it out years before those Mopar engineers. Tunnel ramming and POPIR (port on port, independent runner) systems are subsets when they are down drafted, but the Mopar system is varies due to the internal passages direction. Ram Charger Firepowers were down drafted, whereas early 413/426 Max Wedge cross rams were side draft AFB's, while the later ProStockers were down draft Dominators, so the degree of supercharge due to gravity was heaps higher in the early De Soto and later Hemi 426 intakes.


From https://fordsix.com/forum/viewtopic.php?f=5&t=31668 on » Mon Jun 27, 2011

For me, the variables Vi and Ced and Xa define the nature of the intakes ability to optimize or limit fuel standoff after a basic combination has been ratifed. See below.

Primarily, before discussing those three basic geometric design parameters above, your always stuck with a basic form to test, and then optimize, for in engine development, you always use horse trade from the existing base to the evolutionary optimum. In terms of blue printing options which help, then port miss-matching makes the best fuel standoff preventer you can get. Take for example the antipodean Alloy Head cross flow 4.1 with its 1.3" port, or the iron 250 2V with its 1.65" diameter intake port, or the iron cross flow 4.1 with its 1.38" port. Each is circular, but has a manifold which is often sharply formed and of a lessor diameter than the intake port. Result is no loss of air flow compared to a perfectly port matched intake, but better fuel atomization, and, if one of the common Aussie sedan racer or speedway triple Weber installations is used, you can gain significant mid range torque with no loss of high end power. If the manifold has a 60 thou annular size reduction on intake port, and even better, a 30 degree chamfer, reversion is reduced significantly.

Secondly, you then go to what I think is the Amal information used in port volume and distance to intake. Vincent motor cycles engineering technician Phil Irving had that stuff worked out brilliantly. Repco 2.5 Formal 1 engine optimized those settings. Apparently, according to the Chamerlain brothers account back in 1979, engines suddenly come alive when the reflecting waves are controlled by maintaining intake volumes (Vi) and intake to carb entry distance (Ced) to certain limits. A lot like the famed paint the pipe with acrylic, and saw the exhaust off where the paint stops burning maxims from motorbike tuners. I assume fuel standoff is a definable quotient when the 1st, 2nd,3rd and nth degree order resonances are worked out, and that fuel standoff is actually just a function of air pressure bank-up. So Vi and Ced create an ideal tune.

Phil Irving and others define a flow net geometry cross section, where the number of flow drops to flow paths should form a lattice of squares with orthogonal (90 degree) lines, and from that, pressure gradient is made more even. Basically, the cross sectional area (Xa) can only vary a certain amount from venturi to the intake valve to educe standing wave propitiations.

One other thing. Seams like downdraft installations make a better power curve if they a packaged within the confines of variables Vi and Ced and Xa and IR peak power rpm

For Pipe Max, and how accurate it is, see this BMW M20 engine post...http://speedtalk.com/forum/viewtopic.ph ... 2&start=15


Its have six pages, the link starts on page 2 and is a big read, but spend some time and have some fun...its the small Bimmer six made from 1977 to 1993 or so which the 1986 on wards 325e and 325Is were based. The little six intake in EFi or multiple carb is is crested out by shock towers hood and brake booster, but there is all manner of simulation programs to assess the right Va, Vi, Ced and any anything else. Despite the size, a well worked little Bimmer I6 head is similar to our Falcon six head engines. The guys have attempted to reconcile hp readings way better than expected, and the Pipe Max doesn't even show what is possible with a really well sorted intake.
 
xctasy":7peqtp8l said:
All those important questions you raised are non matters for the graph, only item 1 and 2 are. The curves won't be made if the cam and carb aren't right for that selected venturi and cylinder capacity. It then tells you the rpm range at maximum power, and what reults will work, even if you had the wrong sized intake runner volumes
Hello Xctasy, am I making this too hard? As far as the cam, do I just need to get a cam that operates in the RPM range that coincides with the results from the graft? in this case, 210 cfm worth of head flow matched to a cylinder capacity of 50 cid. equals 4,666 rpm. I go get a cam that is designed to make power in this range & the bigger the lift the better? I think I understand about the intake shape & length aren't extrodinarily important, but having a runner slightly smaller than the intake port opening, to a specific amount, greatly reduces gas flow reversion? So, venturi size in a carb can or is different than the cfm flow its rated at? How do I know if I got the right size cfm flow carburater just because I got one with the right venturi size? I read the BMW article (thank you). I'll have to read it a couple more times. My head hurts.
 
No, your certainly not being hard to teach or difficult in any way. :D

The total inlet runner combo is dependent on what will package. Any time a venturi size is recommended, the total carb size is generally up to 10 mm for a small 25 mm venturi, to as little as 5 mm up for for a 50 mm venturi. Then there is a recommended flow net profile that IR designers like to keep, and that is found in Australian book Tunning for Speed by Phil Irving. Then the runner has to fit the port.

In the Falcon 250, that could be 1.3 to 1.625 circular dimensions or so, depending on head. A 1.1875" 350 or 1.375"500 cfm Holley venturi sits in a 1.5 or 1.6875" throttle bore, so start with a 1.5 or 1.6875" inch tube and link it to the head

It just has to integrate somehow within those limits, and it is the spring towers and brace bars and other stuff has to clear to make it an engineering success.


On a log head, cross section changes widely, and there is no way you can meet any recommended limits from 1st to 8th order harmonic tuning, so why bother is what I say to myself.
 
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