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De-tuning suggestions

1973dodger

Well-Known Member
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Feb 17, 2013
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Location
Seymour, Tn.
I am nearing the end of project on my 1973 Charger and my wallet as well. I bought a replacement 440 race engine to install in my new project. While it is as advertised as the beast it is, it is not a particularly street friendly. I must admit it was not particularly the smartest move on my part and unfortunately speaks to my inexperience. Admittedly, my pride got the best of me in approaching this project in that I was trying to shut-up my "Chevy-loving-in-laws", which this engine will certainly do, but I would like for the engine to be more street-able. I will tell you all I know about engine and my purpose. My purpose for this car is to have good power, but used 95% on the street, and to de-tune this engine as inexpensively as possible. Known specs are as follows; Displacement- 440 honed and sq-blocked bored .30 over, crank balance 10/10, Ohio beam rods, Weisco flat top pistons, Mopar Performance aluminum heads milled .60 thousands and intake port matched to Victor single-plane intake manifold, Mopar performance valves and springs, compression is 10.9 to 1, MP purple shaft cam has .590 lift w/ 312 duration, Proform 750 racing DP carb, Felpro head gasket, Clevite bearings, Menzeire electric water pump, Summit SFI oiling system. Summit 1 7/8 ceramic headers w/ 3" exhaust. This a $10k engine with the millwork that I bought for less than half of that. My question is; can I get by with just a cam swap, if so, what would you suggest? Do I also have to go to a dual plane intake? Do I have to reduce the compression?
 

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Swap cam and valve springs to a more streetable one and install a thick head gasket to lower compression.
 
Sounds street friendly to me.:headbang: what's the problem. Have you driven it? Is it really that bad? With the aluminum heads it should be ok with pump gas. I can see where it would be a pain at redlights, but not un streetable
 
sell the hot engine to somebody who'd love to have it and then build something more suitable to your needs.
 
You're Nuts. MHO
hammer.gif


There is nothing like pulling up next to a Prius or smart car and rattling their windows. or like me just letting it idle in the driveway and making the Ford guy across the street spend more money on his 17 year project to compete. Keep it
 
have you driven it as of yet?what trans combo,rear gears,and rear tire size are you running?
 
What's it doing now on the street that you don't like?

A buddy of mine had that same .590 cam in a 440 with a Weiand tunnel ram and two Holleys in a '67 Belvedere. We used to cruise around on the street with it all the time, never gave him any trouble.

I'd keep it the way it is if I had it.
 
welcome to FBBO... "I think I remember this 73 Charger", being built by Time Machine Inc. from either Mopar Muscle Mag. or DC.com forums/thread a few years back, is that the same car ??, is that it's rendering in your avatar ??... it doesn't sound all to un-street-able to me either... Maybe not a good commute car engine or best for stop & go traffic, but worse case scenario change camshafts, you can bleed off some compression that way too.... maybe you could start a thread in the general discussion section, you may get a few more ideas & responses... good luck
 
have you driven it as of yet?what trans combo,rear gears,and rear tire size are you running?
Rear tires are 285/50/17, rearend is a 8 3/4" w/ 3.90 ratio, transmission is a 727 torque flight w/upgraded clutch discs.
 
You're Nuts. MHO
hammer.gif


There is nothing like pulling up next to a Prius or smart car and rattling their windows. or like me just letting it idle in the driveway and making the Ford guy across the street spend more money on his 17 year project to compete. Keep it
I like the way you think, but it is not cool to be stranded on the side of the road with the radiator puking it's guts out.
 
As long as the cooling system is the proper size and you are running a shroud with your fan or big enough electric fans I really don't see overheating being an issue.
 
It's fine like it is. It'll run on good premium pump gas all day. Run it as is and shut your in laws up.
 
Sounds street friendly to me.:headbang: what's the problem. Have you driven it? Is it really that bad? With the aluminum heads it should be ok with pump gas. I can see where it would be a pain at redlights, but not un streetable

I agree. I wouldn't mind driving it on the street. I don't know if I'd be driving it 90% of the time, though. But I sure would give a try!
 
I was thinking about detuning my streeet car to about those specs you have now........ I'm running a similar motor with a cam that has .636 lift and 314/322 advertised duration on the street. 11.3:1 compression (Indy heads) on pump gas. It would be ok if the car was a standard, but the manual valve body tranny makes it a bit rough in traffic....
 
I was thinking about detuning my streeet car to about those specs you have now........ I'm running a similar motor with a cam that has .636 lift and 314/322 advertised duration on the street. 11.3:1 compression (Indy heads) on pump gas. It would be ok if the car was a standard, but the manual valve body tranny makes it a bit rough in traffic....
Wished I had you guys closer to me to get this thing dialed in. Everyone around here, doesn't know how to work on anything but a chevy. I think the biggest mistake was buying too small of a stall (2400-2800), and put a thermostat in the electric water pump. I have a 4 core radiator with large electric fan w/ shroud, which should cool. I guess the thermostat is restricting the flow too much. Easy fix to take out the thermostat. I'm open to all suggestions, in just a little over my head and don't know where to go from here.
 
Sounds like fun to me, drive it.
If overheating is your main concern just make sure your cooling system is up to par with the engine.
Allot of guys out there with hotter engines and no cooling probs so you can do it too.

update

I think you should run a thermostat, water will go through your radiator to fast and not have time to cool without one.
 
Wished I had you guys closer to me to get this thing dialed in. Everyone around here, doesn't know how to work on anything but a chevy. I think the biggest mistake was buying too small of a stall (2400-2800), and put a thermostat in the electric water pump. I have a 4 core radiator with large electric fan w/ shroud, which should cool. I guess the thermostat is restricting the flow too much. Easy fix to take out the thermostat. I'm open to all suggestions, in just a little over my head and don't know where to go from here.

Sounds like the real issue here is the poor cooling, not the street manners of your motor. First off, what temp is it running at currently? A lot of guys have this idea that 160 is proper running temp when in reality it's 180-190 or even a bit more. Are you sure the cooling passages are free of scale in the block?

There is some debate on this issue, but IMO, t-stats should not be removed as they are placed 'after' the pump and block for a reason. The pump is fighting to move coolant throught the system but the stat sets up a restriction. This forces the coolant into every passage and especially the really hot spots where without lots of coolant replenishment, there might be localized boiling. all this increases thermal contact between coolant and motor = better cooling. A better question is Are you sure the stat is even opening?

What cfm water pump are you running? is it getting proper current / voltage to maintain proper cfm? IMO, running a higher cfm water pump is also a great idea. Cooling efficiency depends on 'delta Temperature' - the diff between the temp of the hot iron and the cool coolant. The more flow, the cooler the coolant remains, so the faster and more effectively the heat flows from the iron to the coolant. also, the faster the coolant flows, the more turbulent it flows through the radiator, so the more coolant is in contact with the rad tubes, thus the more effective the rad is at extracting that heat.

That's about the extent of my suggestions, but maybe your timing is off? I understand it can affect engine temps quite a bit but that's out of my area.

- - - Updated - - -

I just looked at those water pumps - they're beasts... and EXPENSIVE. Says it should be plenty to cool 650 hp at 35 gpm. The bigger one flows 55 gpm (and an intermediate flows 42). As long as it's set up properly, the pump shouldnt be your problem.

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Probably not the case here, but they do sell one for 16V applications but say it will work for limited 12V situations. Sure that isnt the one you're running?

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What make / cfm fan(s) are you running?
 
Wished I had you guys closer to me to get this thing dialed in. Everyone around here, doesn't know how to work on anything but a chevy. I think the biggest mistake was buying too small of a stall (2400-2800), and put a thermostat in the electric water pump. I have a 4 core radiator with large electric fan w/ shroud, which should cool. I guess the thermostat is restricting the flow too much. Easy fix to take out the thermostat. I'm open to all suggestions, in just a little over my head and don't know where to go from here.
Just finish it and drive it. That's not an uber radical race piece, it's just a nice, warmed up combination. It'll do fine on the street. The only thing I'd change, is to ditch the electric pump. Those usually can't move enough water to keep a car cool on the street. You've got plenty of HP on tap, so a few to drive a good water pump won't be missed. I can't tell what distributor that is,or if it has a vacuum advance, but I'd run a good ignition and I'd keep some timing in it down low. I run mine locked out at 34 degrees on the street with no vacuum advance. Low initial timing builds heat.
 
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