318 MAX fuel economy builds?

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Bewy said:
The problem with Rhoads is there are so many variables that affect their operation:
- spring tension. More spring, & they bleed down more
- rocker ratio. More ratio , they bleed down more
- oil viscosity. Thin oil they bleed down more, thicker oil they bleed down less.
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I have to say that modern VVT timing engines also depend on all of the factors that you mention regarding oil. Once an engine gets to temp it is going to be very consistent just at the new cars are unless the oil degrades or the passages get clogged. The spring thig is real but it won't change daily. You will get what you get and I don't see rocker ratio being an issue in any way. New cams come with enough lift that even down .025 they will exceed stock 2 barrel cams.

Like I said. I'm running a set on my 273 with a 213 @ .050 cam and it pulls over 21" of vacuum at idle. If the 273 don't struggle down low I don't see how a 360 would.

But it's a theory and I'm trying to gather the things needed to test it. The thing about Rhoads is if you don't want the vvt affect you just adjust them like a normal lifter with zero lash. This is also a great way to test the effects of the lifters themselves. I have driven my car with zero lash and then adjusted it to .025 then driven it again in the same day. Guess which setting idles smoother, has more low end torque and gets better mileage?
 
Too much time wasted on a single aspect of the projects. I'm running a 1916 Edelbrock Avs2. The 1906 and the 1916 have different annular discharge venturi secondaries. The 1916 is advertised as as close as FI as you can get with a carb. I have run both versions and I agree with the ad. Who else is running the 1915 16 or the 800 cfm version and what are your thoughts on it's affect on mileage and performance?

Also I have had the Thermoguard recommended to me by more than one guy. Who's a fan of the Thermoquad and what are your favorite aspects of them that motivate you to recommend them on a mileage car?
 
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Dmopower said:
Too much time wasted on a single aspect of the projects. I'm running a 1916 Edelbrock Avs2. The 1906 and the 1916 have different annular discharge venturi secondaries. The 1916 is advertised as as close as FI as you can get with a carb. I have run both versions and I agree with the ad. Who else is running the 1915 16 or the 800 cfm version and what are your thoughts on it's affect on mileage and performance?
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Advertised. Boy, they got you hook, line and sinker. Run it all like you want. You're gonna do it anyway. I don't even know why you asked for opinions.
 
Dmopower said:
This is also a great way to test the effects of the lifters themselves. I have driven my car with zero lash and then adjusted it to .025 then driven it again in the same day. Guess which setting idles smoother, has more low end torque and gets better mileage?
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.025 down front the top or .025 off the bottom?
 
Dmopower said:
You set them the same way you would a solid cam.
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No no no, your quiz above on which way it ran best.

“I have driven my car with zero lash and then adjusted it to .025 then driven it again in the same day.”

You gave it .025 lash? Zero lash? But not depressed.”025?
 
Standard lifters?

Section from what I read at there site.

“At this point, tighten the locknut until the plunger is compressed at least a sixteenth of an inch below the retaining ring (approximately 3/4 turn for a Small Block Chevy). While the amount the plunger is compressed is not critical, the important thing to remember is that the plunger must be compressed below the retaining ring so that there is no clearance or looseness in the valvetrain whatsoever, but not so much that the plunger bottoms out on the lifter shell.”

Istallation Instructions

What exact model lifter?
 
None of those instructions actually mentions the V pro street I'm running. I'm going to look for the instructions that came with my lifters. If I can't find them I'll be ordering another set next month. I can get the actual instructions for them then.
 
Dmopower said:
None of those instructions actually mentions the V pro street I'm running. I'm going to look for the instructions that came with my lifters. If I can't find them I'll be ordering another set next month. I can get the actual instructions for them then.
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Not hard to find.
 
Dmopower said:
Too much time wasted on a single aspect of the projects. I'm running a 1916 Edelbrock Avs2. The 1906 and the 1916 have different annular discharge venturi secondaries. The 1916 is advertised as as close as FI as you can get with a carb. I have run both versions and I agree with the ad. Who else is running the 1915 16 or the 800 cfm version and what are your thoughts on it's affect on mileage and performance?

Also I have had the Thermoguard recommended to me by more than one guy. Who's a fan of the Thermoquad and what are your favorite aspects of them that motivate you to recommend them on a mileage car?
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Go and read my posts here: How much for 71 Thermoquad?

If you filter the BS from the usual idiots I've explain how they work from a metering standpoint.

In all honesty its probably the greatest OEM 4 barrel carb ever built.
 
Dmopower said:
None of those instructions actually mentions the V pro street I'm running. I'm going to look for the instructions that came with my lifters. If I can't find them I'll be ordering another set next month. I can get the actual instructions for them then.
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Ahhhhhhhh, the V-Pro lifter, yup! Different ball game.
Gotcha. You probably mentioned that before and I forgot.
OK - back on the same page now.
 
rumblefish360 said:
Ahhhhhhhh, the V-Pro lifter, yup! Different ball game.
Gotcha. You probably mentioned that before and I forgot.
OK - back on the same page now.
Click to expand...
I did mention it earlier but I clearly confused my lifter instructions with the standards lifter instructions. That's why I removed those posts. Good catch.
 
Dmopower said:
I have to say that modern VVT timing engines also depend on all of the factors that you mention regarding oil. Once an engine gets to temp it is going to be very consistent just at the new cars are unless the oil degrades or the passages get clogged. The spring thig is real but it won't change daily. You will get what you get and I don't see rocker ratio being an issue in any way. New cams come with enough lift that even down .025 they will exceed stock 2 barrel cams.

Like I said. I'm running a set on my 273 with a 213 @ .050 cam and it pulls over 21" of vacuum at idle. If the 273 don't struggle down low I don't see how a 360 would.

But it's a theory and I'm trying to gather the things needed to test it. The thing about Rhoads is if you don't want the vvt affect you just adjust them like a normal lifter with zero lash. This is also a great way to test the effects of the lifters themselves. I have driven my car with zero lash and then adjusted it to .025 then driven it again in the same day. Guess which setting idles smoother, has more low end torque and gets better mileage?
Click to expand...
The rocker ratio changes the spring load seen at the lifter....., 250# OTN is 375# at the lifter w/a 1.5, 400# w/a 1.6, etc......
 
Killer6 said:
The rocker ratio changes the spring load seen at the lifter....., 250# OTN is 375# at the lifter w/a 1.5, 400# w/a 1.6, etc.....
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Very good and I do not debate this. On the Rhoads site they have a question and answer section and they claim that valve spring pressure is not an issue because the lifters bleed down is based on engine speed and the time the bleed hole has to bleed and is lined up and able to bleed down. Since liquid does not compress I assume and that's all it is is a hypothesis bases on their statmente that the ratio and spring pressure varying to a degree of changing the way the lifters perform will be minimal and not noteworthy for my application at least.

I say that because I'm building a max mileage engine and the lifters will be bled down 99% of the time and I'll only use them pumped up on rare occasions. When they pump up will not be as critical as it would be for someone monitoring their quarter mile et ect.
 
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I have no idea how some of you guys are getting 20+ mpg on an old carbureted V8. I'm measuring my MPG super closely, and I have to wonder if everyone else is doing the same. I fill up the car, log every mile I drive, fill it up again, and calculate accordingly based on distance driven and fuel used. I have been doing this for every tank for 25+ years, initially because the fuel gauge didn't work and now just out of habit. So I'm darn sure my MPG calculations are as accurate as possible.

My current setup is this:

Stock heads, standard bore 5.9 Magnum. Engine doesn't burn any oil or smoke at all.
Factory EFI, factory tune (1994 OBD1 PCM). Injectors are clean, fuel atomization is perfect.
Mopar M1 EFI intake
Hughes SER0814ALN-14 roller cam with their Magnum springs
Comp roller rockers
46rh transmission with lockup converter.
Doug's long tube headers into 2.5" exhaust.
Electric fan
3.23 gear

With my 26.5 inch tire I'm spinning about 1700 rpm at 60 mph, and the best I have ever gotten on at 80 mile highway trip is 19.6 mpg. Admittedly that was at about 70 mph, and that highway has some hills so it would be better on flat ground, but that was me TRYING to make MPG (careful throttle modulation, don't stomp on it, etc).

Before the 46rh I had a 904 with a ~2200 rpm converter, and the absolute best I ever got was 16 mpg. That was taking it super easy on country roads running around 55 mph. On the highway at 65 mph I would get a little above 15 mpg, so I guess the 46rh giving me +4.5 mpg on the highway is pretty good.

I'm sure the stock cam would be better for MPG, but I don't think a lot better. My cam doesn't have a ton of duration since it's designed to work with the factory tune. Also, I went from the stock kegger intake to the M1 intake back when I still had a 904 trans, and I actually got BETTER highway MPG. The 904 trans + 3.23 gear was turning 2600 - 2700 rpm on the highway. I think going back to the stock intake with the OD would probably be better for MPG; that kegger is a low end torque monster, but dies around 4500 rpm.

Before the EFI 5.9 I was running a slightly warmed over 318, Eddy 1406, 904 trans, factory converter, and 3.23 gears. The absolute best I ever got was 15 mpg on an 80 mile highway trip, running at 60 mph or less the whole way. Usually that setup got me 14 mpg on the highway, 13 mpg around town / mixed driving, and 11 - 12 mpg if I had my foot into it a lot.
 
autopar3000 said:
I have no idea how some of you guys are getting 20+ mpg on an old carbureted V8. I'm measuring my MPG super closely, and I have to wonder if everyone else is doing the same. I fill up the car, log every mile I drive, fill it up again, and calculate accordingly based on distance driven and fuel used. I have been doing this for every tank for 25+ years, initially because the fuel gauge didn't work and now just out of habit. So I'm darn sure my MPG calculations are as accurate as possible.

My current setup is this:

Stock heads, standard bore 5.9 Magnum. Engine doesn't burn any oil or smoke at all.
Factory EFI, factory tune (1994 OBD1 PCM). Injectors are clean, fuel atomization is perfect.
Mopar M1 EFI intake
Hughes SER0814ALN-14 roller cam with their Magnum springs
Comp roller rockers
46rh transmission with lockup converter.
Doug's long tube headers into 2.5" exhaust.
Electric fan
3.23 gear

With my 26.5 inch tire I'm spinning about 1700 rpm at 60 mph, and the best I have ever gotten on at 80 mile highway trip is 19.6 mpg. Admittedly that was at about 70 mph, and that highway has some hills so it would be better on flat ground, but that was me TRYING to make MPG (careful throttle modulation, don't stomp on it, etc).

Before the 46rh I had a 904 with a ~2200 rpm converter, and the absolute best I ever got was 16 mpg. That was taking it super easy on country roads running around 55 mph. On the highway at 65 mph I would get a little above 15 mpg, so I guess the 46rh giving me +4.5 mpg on the highway is pretty good.

I'm sure the stock cam would be better for MPG, but I don't think a lot better. My cam doesn't have a ton of duration since it's designed to work with the factory tune. Also, I went from the stock kegger intake to the M1 intake back when I still had a 904 trans, and I actually got BETTER highway MPG. The 904 trans + 3.23 gear was turning 2600 - 2700 rpm on the highway. I think going back to the stock intake with the OD would probably be better for MPG; that kegger is a low end torque monster, but dies around 4500 rpm.

Before the EFI 5.9 I was running a slightly warmed over 318, Eddy 1406, 904 trans, factory converter, and 3.23 gears. The absolute best I ever got was 15 mpg on an 80 mile highway trip, running at 60 mph or less the whole way. Usually that setup got me 14 mpg on the highway, 13 mpg around town / mixed driving, and 11 - 12 mpg if I had my foot into it a lot.
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Speaking for myself. When I say I'm shooting for 20 mpg. That pulling up to a station on a road trip then rolling down the highway till we stop to eat, pee or refill. So I'm only speaking open road documented miles and....I am still in the process, so I have not achieved that goal yet.
 
Dmopower said:
Very good and I do not debate this. On the Rhoads site they have a question and answer section and they claim that valve spring pressure is not an issue because the lifters bleed down is based on engine speed and the time the bleed hole has to bleed and is lined up and able to bleed down. Since liquid does not compress I assume and that's all it is is a hypothesis bases on their statmente that the ratio and spring pressure varying to a degree of changing the way the lifters perform will be minimal and not noteworthy for my application at least.
Click to expand...
Truly the spring seat load is the force depressing the plunger as it bleeds off, which can be anywhere from a stk HP 340 @70#, to 140# for a decent dual spring × whatever rocker ratio. Once any preload has been bled off, then it does become a function of oil pressure & orifice dimension.
As to OE VVT/VTEC etc., they are specific & are sensitive to beyond parameter changes, they assume OE spec oil viscosity & monitor oil temp & pressure to adapt the controlling OCV's or magnetic actuators. Toyota,..yes Toyota, screwed the pooch when going for the gas mileage gold w/the Camry mill, and those systems wouldn't function on the reduced viscosity as factory filled & specified. The fix, go back to 10W-30, the system just wasn't calibrated for super light weight oil.
I'm curious to see how You & the OP fare in Your individual mpg quests.
 
Dmopower said:
Speaking for myself. When I say I'm shooting for 20 mpg. That pulling up to a station on a road trip then rolling down the highway till we stop to eat, pee or refill. So I'm only speaking open road documented miles and....I am still in the process, so I have not achieved that goal yet.
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Yup, that's the way to do it. When I say I got 19.6 mpg on the highway, that's (almost) how it was done. I filled up at a station just off the highway, got to my destination which is about a mile off the highway, then the next day drove about 2 miles to fill it up.
 
Killer6 said:
Truly the spring seat load is the force depressing the plunger as it bleeds off, which can be anywhere from a stk HP 340 @70#, to 140# for a decent dual spring × whatever rocker ratio. Once any preload has been bled off, then it does become a function of oil pressure & orifice dimension.
As to OE VVT/VTEC etc., they are specific & are sensitive to beyond parameter changes, they assume OE spec oil viscosity & monitor oil temp & pressure to adapt the controlling OCV's or magnetic actuators. Toyota,..yes Toyota, screwed the pooch when going for the gas mileage gold w/the Camry mill, and those systems wouldn't function on the reduced viscosity as factory filled & specified. The fix, go back to 10W-30, the system just wasn't calibrated for super light weight oil.
I'm curious to see how You & the OP fare in Your individual mpg quests.
Click to expand...
I agree and understand that when I pick my oil weight, springs which will be stock hp and engine temp. What I get is what I will get. It isn't a computer program that's for sure. But I'll take whatever I get on top and hope for 20 on the road. My goal is 20 mpg on the open road and under 14 sec in the quarter. If I accomplish this I'll have a fine daily driver while I finish buying parts and building the car.

Thanks for the help and interest. This is the car.

298757071_4833249856777084_411569611734082471_n.jpg
 
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autopar3000 said:
Yup, that's the way to do it. When I say I got 19.6 mpg on the highway, that's (almost) how it was done. I filled up at a station just off the highway, got to my destination which is about a mile off the highway, then the next day drove about 2 miles to fill it up.
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What did you get 19 plus driving?
 
Dmopower said:
You may be right. My thought was after reading posts from guys porting these 920 heads is that they are in the 135 cc port volume area. The j heads factory are in the 170 area. That last number may be wrong but assuming it is 170 that's 25% more volume moving the same cfm. Thats without calculating in the increase piston speed as little as it may be and I get heads capable of similar hp as factory J heads with a much more efficient 1000 to 3500 rpm and a much better quench allowing me to take advantage of as much timing as possible. No?
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Just my two cents, but I would just hit the easy button and run a set of magnum heads. Closed chamber, port velocity, hardened seats, and flow is already baked in for what you are trying to do. Have a good valve job done and run them.
 
Dmopower said:
I agree and understand that when I pick my oil weight, springs which will be stock hp and engine temp. What I get is what I will get. It isn't a computer program that's for sure. But I'll take whatever I get on top and hope for 20 on the road. My goal is 20 mpg on the open road and under 14 sec in the quarter. If I accomplish this I'll have a fine daily driver while I finish buying parts and building the car.

Thanks for the help and interest. This is the car.

View attachment 1716017280
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Nice looking ride @Dmopower. Your mileage and power build isn't everyone's cup of tea, but it is right up my alley.

I took a different approach back in 1994 I put a 518 in my 340 challenger. It would knock down 20mpg on the highway provided I kept my foot out of it.

There are some good threads on moparts you would be interested in. Look for super duper 318 and super duper 5.9 threads by @hotroddave. Not sure if he is on Abodies or not.
 
mgoblue9798 said:
Nice looking ride @Dmopower. Your mileage and power build isn't everyone's cup of tea, but it is right up my alley.

I took a different approach back in 1994 I put a 518 in my 340 challenger. It would knock down 20mpg on the highway provided I kept my foot out of it.

There are some good threads on moparts you would be interested in. Look for super duper 318 and super duper 5.9 threads by @hotroddave. Not sure if he is on Abodies or not.
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Thank you and thanks for the information.
 
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