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Re: lowest reasonable highway rpm for a 440?
[Re: Twostick]
#1058371
08/22/11 12:53 AM
08/22/11 12:53 AM
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Joined: Jan 2005
Posts: 12,494
Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,494
Kalispell Mt.
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With a scanner hooked up to my 97 ram reading live data and cruise set on 70 MPH on a straight leval road with no wind, it needs a higher throttle angle to maintain 70 in direct than it does in OD, also the overhead console instant readout goes up 3 or 4 mpg when switching the OD on and back down when you turn it off. Also since it is only useing 25% throttle to maintain 70 in OD I bet it could handle even higher gears and get a little better MPG, I am confidant returns would diminish but still be there.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: lowest reasonable highway rpm for a 440?
[Re: Twostick]
#1058372
08/22/11 01:39 AM
08/22/11 01:39 AM
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Joined: Jul 2008
Posts: 30,632
Florida STAYcation
IcorkSOAK
Financed his waterbed
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Financed his waterbed
Joined: Jul 2008
Posts: 30,632
Florida STAYcation
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Quote:
Here's my experience with tall geared (don't start Doc) heavy vehicles.
Kevin
K-guy ....I would never debate what you cRaZy CaNaDiAnS might term as heavy or light .... B U T a 2.75 rear-end ratio is a SHORT gear. 
SHORT in numbers  , SHORT in times it turns the axles ... it is a little, itty, bitty gear .... what MORE do you want ? .... 
ORE is stuff in Sears & ROEbuck ONT that turned-around and topsey/turvey ? ..  
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Re: lowest reasonable highway rpm for a 440?
[Re: feets]
#1058373
08/22/11 03:48 AM
08/22/11 03:48 AM
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Joined: Jun 2008
Posts: 10,958
Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,958
Oakdale CT
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Quote:
1700 rpm seems pretty low for a 440 to lug around that much weight. Is that too low for an efficient cruise?
My 2WD Dodge Ram rolls down the interstate around 1800 with a 5.2, I suspect you won't have any problem at all.
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Re: lowest reasonable highway rpm for a 440?
[Re: feets]
#1058374
08/22/11 07:18 AM
08/22/11 07:18 AM
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Joined: Jan 2003
Posts: 3,719
Space Station #5
471Magnum
master
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master
Joined: Jan 2003
Posts: 3,719
Space Station #5
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Definitely need to differentiate between fuel injection and carburetion.
You can get the fuel to atomize, mix and distribute evenly at pretty much any rpm with FI.
A carb is going to require some velocity, which is why the idle circuit has to run a bit richer to compensate, more so with a square bore like a Holley.
Shoot for 2000+ rpm and you'll be happy with the throttle response and fuel economy (relatively speaking anyway).
If I make the Power Tour next year, I'll be putting in my 2.76s and rolling about 2200 rpm at 70 mph. Did the same thing in my 440 Six Pack Challenger in 2010 and averaged over 16 mpg. No vacuum advance either. I'd expect better with my T-quad equipped 360/410 stroker in the Road Runner. I got over 14 mph with 3.55s on the way to Nationals this year.
-Jim
I can fix it... my old man is a television repairman.
He's got the ultimate set of tools... I can fix it.
Currently Mopar-less
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Re: lowest reasonable highway rpm for a 440?
[Re: hooziewhatsit]
#1058375
08/22/11 07:52 AM
08/22/11 07:52 AM
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Joined: Jan 2006
Posts: 8,162
USA
360view
Moparts resident spammer
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Moparts resident spammer
Joined: Jan 2006
Posts: 8,162
USA
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Quote:
360View, I crunched some numbers real quick...
Assuming a BMEP of 100 psi, we can figure the needed torque to be roughly 275 ft-lbs, at that 1700 RPMs.
So, does it make sense that if we build an engine with that amount of torque at that rpm, adjust the rest of the gearing as needed to get a good highway speed at that rpm, that we should get the optimal mileage out of it?
Of course, depending on the air & rolling resistance, I guess we may still need more power to move along though...
We need the vacuum gauge readings of the actual engine to
'gues-ti-mate'
a BMEP.
1 inch of manifold vacuum showing on the gauge would be 'about' 110 to 120 BMEP at 1700 rpm
6 inches of vacuum showing on the gauge would be less, maybe 50 to 70 BMEP
20 inches of vacuum showing on the gauge would be about zero BMEP,
or what you get idling at 1700 rpm
If you figure up the total square inches of eight pistons on the engine,
you can run your finger down the near vertical lines marked
'HP/SQ In'
to find horsepower at any given BMEP
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Re: lowest reasonable highway rpm for a 440?
[Re: 360view]
#1058377
08/22/11 10:28 AM
08/22/11 10:28 AM
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Joined: Jan 2005
Posts: 12,494
Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,494
Kalispell Mt.
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My 68 cuda with the MPG 318 motor cruising at 1700 would hold about 19 inches of vaccume, it needed another gear real bad for better MPG.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: lowest reasonable highway rpm for a 440?
[Re: 360view]
#1058378
08/22/11 10:28 AM
08/22/11 10:28 AM
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Joined: Jan 2003
Posts: 28,114
Irving, TX
feets
OP
Senior Management
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OP
Senior Management
Joined: Jan 2003
Posts: 28,114
Irving, TX
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The EFI does have an interesting effect. When I cruised from Shreveport to Dallas in the hot rod I was using 17% throttle to hold 70 mph. That was 2700 rpm. I don't remember what the MAP reading was. There's a slim chance I still have that data log.
As for my turbos, they are fairly small for the engine. They spool easily. When cruising the hot rod I could open the throttle the slightest bit and watch the boost start creeping upwards. Less than 1/4 throttle would take the hot rod from 60 to 90 when going around a truck.
Add the resistance of an extra 1500 to 1800 lbs and it will load the turbos a bit more.
We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind.
- Stu Harmon
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Re: lowest reasonable highway rpm for a 440?
[Re: chargervert]
#1058380
08/22/11 01:39 PM
08/22/11 01:39 PM
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Joined: Jan 2003
Posts: 4,821
Moved to N.E. Tennessee
GomangoCuda
master
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master
Joined: Jan 2003
Posts: 4,821
Moved to N.E. Tennessee
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Quote:
As long as you don't mind that he paints his Keith Black Chrysler designed Hemi engines Ford blue and has the Ford logo cast into the valve covers,in a vain attempt to decieve unknowing NHRA fans into believeing that Ford actually builds an engine that can compete in top fuel/funnycar competition.
Where have you been the last few years. Sure it is similar but it is not a KB Hemi engine with ford on the valve covers. Read the article below from the 2007 SEMA show. In March 2010 they signed a new 5 year contract with Ford to supply these engines and parts to other Ford teams, specifically Bob Tasca. http://sports.espn.go.com/rpm/racing/nhra/news/story?id=5033830
===========================================================
The Ford BOSS 500 Nitro Drag Racing Engine:
Racing enthusiasts know that the true heart of a race car is its engine – and Davis wants to make sure that the “heart” that powers NHRA Funny Car Mustangs of John Force Racing is pumping “blue” blood in the future.
Davis and John Medlen of John Force Racing challenged themselves to develop the new Ford BOSS 500, the first modern nitro engine for drag racing. The BOSS 500 was tested on-track for the first time on Oct. 18 and was unveiled for media today.
“We wanted to be in NHRA Funny Car with an engine that we really could call all our own,” Davis said. “I wanted people to see a Ford Mustang race car and know that it’s winning races with true Ford power.”
Davis and Medlen looked at the current nitro engine, discussed where they felt it had weaknesses, and decided to design and build a new engine to address them.
The BOSS 500 is the first nitro drag racing motor designed with analytical tools. It has a strengthened block for better durability and new cylinder heads developed by Ford and Force engineers. The basic design will favor areas such as the main caps register and the main webs in the block. Its engine block also is anodized blue after machining, helping ensure fans and competitors alike know when they’re seeing a Ford nitro engine under the hood.
Most of the external surface areas on the new 500-cubic-inch engine have been redesigned; a new belly pan was designed for better sealing; and the valve covers purposely call back the old Ford BOSS motors. The engine also features Ford main bearings with actual parts numbers in the Ford performance catalog.
“We had three things in mind when we set out on this project,” Davis said. “First, for marketing purposes, we wanted to say that we were putting reality behind the term ‘Powered by Ford.’
“Second, on the technical side, we have always helped out with aero, chassis development and now safety, but we always stopped short of the engine. This project has been a technical exercise for our engineers and the Force team to take the current motor, redesign it and make it
a Ford.
“Finally, we want fans to associate this engine with Ford and Force, but we also know this provides a new revenue opportunity for us,” Davis added. “In Funny Car, the plan is for this to be a John Force Racing-exclusive engine at the start, but we do want to be able to sell it to Top Fuel teams for competition in the near future.”
Davis said that the current plan is for new Force Mustang driver Mike Neff to use the Ford BOSS 500 engine full-time in 2008 as it goes through its development phase. The other Force Mustang drivers – John Force, Ashley Force and Robert Hight – will use the engine after it has been further developed.
Ford and Force Racing also are investigating a team to be the first development operation in Top Fuel, with a measured, commercial rollout to more competitors after it has gone through a prove-out stage in that division.
In theory, there is no difference between theory and practice. In practice, there is.
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Re: lowest reasonable highway rpm for a 440?
[Re: CrAzYMoPaRGuY]
#1058383
08/22/11 02:06 PM
08/22/11 02:06 PM
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Joined: Jul 2008
Posts: 30,632
Florida STAYcation
IcorkSOAK
Financed his waterbed
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Financed his waterbed
Joined: Jul 2008
Posts: 30,632
Florida STAYcation
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Quote:
What about a 2.76 gear with an Eddy head.... on a stroked big block?
THIS coming from a cRaZy guy with a little-itty-bitty A engine in a big HUGE and uNaero motorhomely ? ... 
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Re: lowest reasonable highway rpm for a 440?
[Re: GomangoCuda]
#1058385
08/22/11 03:19 PM
08/22/11 03:19 PM
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Joined: Sep 2004
Posts: 16,040
RI Deep in the rust belt
chargervert
I Live Here
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I Live Here
Joined: Sep 2004
Posts: 16,040
RI Deep in the rust belt
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Quote:
Quote:
As long as you don't mind that he paints his Keith Black Chrysler designed Hemi engines Ford blue and has the Ford logo cast into the valve covers,in a vain attempt to decieve unknowing NHRA fans into believeing that Ford actually builds an engine that can compete in top fuel/funnycar competition.
Where have you been the last few years. Sure it is similar but it is not a KB Hemi engine with ford on the valve covers. Read the article below from the 2007 SEMA show. In March 2010 they signed a new 5 year contract with Ford to supply these engines and parts to other Ford teams, specifically Bob Tasca. http://sports.espn.go.com/rpm/racing/nhra/news/story?id=5033830
===========================================================
The Ford BOSS 500 Nitro Drag Racing Engine:
Racing enthusiasts know that the true heart of a race car is its engine – and Davis wants to make sure that the “heart” that powers NHRA Funny Car Mustangs of John Force Racing is pumping “blue” blood in the future.
Davis and John Medlen of John Force Racing challenged themselves to develop the new Ford BOSS 500, the first modern nitro engine for drag racing. The BOSS 500 was tested on-track for the first time on Oct. 18 and was unveiled for media today.
“We wanted to be in NHRA Funny Car with an engine that we really could call all our own,” Davis said. “I wanted people to see a Ford Mustang race car and know that it’s winning races with true Ford power.”
Davis and Medlen looked at the current nitro engine, discussed where they felt it had weaknesses, and decided to design and build a new engine to address them.
The BOSS 500 is the first nitro drag racing motor designed with analytical tools. It has a strengthened block for better durability and new cylinder heads developed by Ford and Force engineers. The basic design will favor areas such as the main caps register and the main webs in the block. Its engine block also is anodized blue after machining, helping ensure fans and competitors alike know when they’re seeing a Ford nitro engine under the hood.
Most of the external surface areas on the new 500-cubic-inch engine have been redesigned; a new belly pan was designed for better sealing; and the valve covers purposely call back the old Ford BOSS motors. The engine also features Ford main bearings with actual parts numbers in the Ford performance catalog.
“We had three things in mind when we set out on this project,” Davis said. “First, for marketing purposes, we wanted to say that we were putting reality behind the term ‘Powered by Ford.’
“Second, on the technical side, we have always helped out with aero, chassis development and now safety, but we always stopped short of the engine. This project has been a technical exercise for our engineers and the Force team to take the current motor, redesign it and make it
a Ford.
“Finally, we want fans to associate this engine with Ford and Force, but we also know this provides a new revenue opportunity for us,” Davis added. “In Funny Car, the plan is for this to be a John Force Racing-exclusive engine at the start, but we do want to be able to sell it to Top Fuel teams for competition in the near future.”
Davis said that the current plan is for new Force Mustang driver Mike Neff to use the Ford BOSS 500 engine full-time in 2008 as it goes through its development phase. The other Force Mustang drivers – John Force, Ashley Force and Robert Hight – will use the engine after it has been further developed.
Ford and Force Racing also are investigating a team to be the first development operation in Top Fuel, with a measured, commercial rollout to more competitors after it has gone through a prove-out stage in that division.
So basically for marketing purposes they took the current engine,which is Chrysler/Keith Black designed,and copied it then painted it blue and put Ford valve covers so they could call it"Ford powered" Got it! Thats the same thing Toyota the Waltrips and Bill Davis racing did to Dodge with the Nascar engine! Copyright infringement is the sincerest form of flattery these days isn't it?
Last edited by chargervert; 08/22/11 03:23 PM.
70 Charger R/T SE 472 Hemi
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70 Challenger convertible
71 Challenger convertible
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Re: lowest reasonable highway rpm for a 440?
[Re: feets]
#1058386
08/22/11 03:24 PM
08/22/11 03:24 PM
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Joined: Jan 2003
Posts: 104,346
Garden Grove, CA
OzHemi
Penguin-hating Ginger
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Penguin-hating Ginger
Joined: Jan 2003
Posts: 104,346
Garden Grove, CA
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Quote:
Quote:
What about a 2.76 gear with an Eddy head.... on a stroked big block?
More cubes under those Eddy heads might be helpful at low rpms...?
More cubes = bigger mouth to feed. Fuel consumption is part of the issue.
I already have a 3.23 and everything to put the 518 in the car. When it comes to inches I have turbochargers to multiply the amount of air it breathes.
Just put the car all together and see what it's like....easy enough to always play around with diff ratios once you have everything else in place. 
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Re: lowest reasonable highway rpm for a 440?
[Re: CrAzYMoPaRGuY]
#1058388
08/24/11 10:35 PM
08/24/11 10:35 PM
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Joined: May 2006
Posts: 236
Southern CA
Colin Frolick
enthusiast
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enthusiast
Joined: May 2006
Posts: 236
Southern CA
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Feets you know i have a 71 imp, with a 493. it came with 3.23s, i've swapped in 2.76s and it much much MUCH better on the highway (but noticeably weaker from a standstill). i live out in the desert and drive alot at 70-80-90mph on the southern california freeways. it could use even LESS gear and be fine, so when i get to it i have a non-lockup 518, a new "tight" converter, and i want to try 3.73s, those * 0.69 od = a 2.574 final drive. my 65 pontiac tempest ran last with a 455/6-speed/3.23 rear. the trans was 0.76 od, so a 2.45 final drive. 19mpg from Denver to soCal. my new rear end for that car is 3.00:1 so 2.28 final drive. had a c5 z06 corvette, top gear in that car was 1.90:1 final. i know these are quite different (meaning, lighter!) cars but make interesting examples. does your imperial also have an 8 3/4 axle? if so... easy to change!! pics on http://www.flickr.com/photos/hpivonka/sets/72157600005938126/
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Re: lowest reasonable highway rpm for a 440?
[Re: feets]
#1058389
08/25/11 08:59 AM
08/25/11 08:59 AM
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Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
patrick
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
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Quote:
I was just running the numbers for the OD swap in the Imperial.
I will be using Edelbrock heads on a stock-ish cam 440 and shoving around a 5300 lb Imperial. It wears 3.23 gears out back.
Without OD I'm looking at 2500 rpm for 65 mph and 2900 rpm for 75 mph.
With OD I'm looking at 1700 rpm for 65 mph and 2000 rpm for 75 mph.
1700 rpm seems pretty low for a 440 to lug around that much weight. Is that too low for an efficient cruise? Stepping up to 3.55 gears would increase rpm by 250 or so.
Please stay away from the "engine should run at peak torque rpm blah blah blah" uneducated BS. We all know that's not true in the real world. If it were true, our cars would get amazing mileage at 4000 rpm.
On the up side of things, with the 3.23 and 518 if I could hit 6000 rpm the car would be cruising at 228 mph.
Do you think John Force has a spare engine I could borrow? 
FWIW, my old truck, a '96 ram with a 318/5speed and 4700 lbs, with 3.21 gears and 30" tires (275/60R17) was 2000RPM at 70mph, and the little 318 pulled it along the highway just fine....never had to downshift going up hills above 65mph.
1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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Re: lowest reasonable highway rpm for a 440?
[Re: feets]
#1058390
08/25/11 10:32 AM
08/25/11 10:32 AM
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Joined: Jan 2003
Posts: 5,406
Pikes Peak Country
TC@HP2
master
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master
Joined: Jan 2003
Posts: 5,406
Pikes Peak Country
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Quote:
Please stay away from the "engine should run at peak torque rpm blah blah blah" uneducated BS. We all know that's not true in the real world. If it were true, our cars would get amazing mileage at 4000 rpm.
Gee, didn't know it bugged you so much. Thanks for the underhanded compliment.
If you paid attention to what I said in those types of posts, I always used the caveat "within reason" of rpm range, being that even an uneducated BSer can tell that a 4000 rpm torque peak is a stupid place to run a cruise rpm.
I've always said to build so you have as low an rpm torque peak as possible. That is how I built my truck engine. Doing so allowed me to maximize the cruising performance and mileage in the rpm range I most typically use during driving. The fact that my torque peak was within that range was the result. Sometime in the last few months the target chart posted further up above was posted and I started comparing my build info to its data. Interestingly enough, while not in the sweet spot, I am not too far away from it either. So while WOT torque peaks are not an exact indicator of efficiency, combine that with vacuum readings and piston speed and you can get dialed in pretty close to building exactly what you want. So don't wholesale discount the WOT torque peak as an efficiency indicator. It is a fact that torque production and volumetric efficiency go hand in hand. Use that as an additional tool in caclulating the peices you need for the build.
In one of the recent enthusiasts rags they had an article recently regarding the GM 8.1 big blocks. The are really big, inefficient pigs with no aftermarket support until just recently. Dart has taken to building a lot of parts for them lately because some oil field came to them requesting big torque, low rpm motors to replace some of their pump units. Seems they produced some gas engines that make some crazy amount of torque at stupid low rpm range. Performance is almost diesel like. Sounds like a build of this sort may be exactly what your after in a car that cruises at 2000 rpm or lower. I'll try to find it an post up some info if no one else beats me to it.
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