LESS THAN 9.5 MPG CITY DRIVING!!!

KRUISR

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The chart you posted looks like the EPA ratings on fuelecomony.gov. EPA runs a very specific test. With careful driving I have beaten their numbers with EVERY vehicle I have ever owned. An example - I had a 98 Ford Contour V6 5spd as a DD. EPA rating is 9.0 L/100km (26 MPG) highway. I have achieved 6.9 L/100km (34 MPG) highway on a 280 km two way run of highway only and averaged 8.5 L/100km (27.5 MPG)City and Highway combined over 3 year 60,000+ km period.
 
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CAMTWO1070

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Dec 17, 2021
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The lobe sepration of the camshaft and the pushrod length are important too...Twisted wedge heads although say works with stock pistons really doesnt as you want the flame kernel dead middle on the piston and non-dished pistons with pistons below deck height cannot achieve such a task.....


Plus on street engines to maximize efficiency you need atleast 10:5:1 compression and the pistons shuld be flush with the deck or a max of .045" out of the hole to help with flame kernel shape too...

IMG_20220424_154128.jpg


A longer stroke and longer rods help alot too because with longer rods and larger stroke it alleviates the thrust stresses on the piston tops that shorter strokes exhibit...A neutral balance helps out heaps too...My 410w idles and runs as smooth as a european made engine....

I built a 347 stroker and put a Vortec V1 and of course it was tuned as anything built out of the normal needs to be tweaked especially the MAF transfer but once everything was tuned and Wideband 02 controller hooked up I was getting 18mpg...........

In the twisted wedge instructions on the last page theres this and a thing most overlook also to mention theres alot more to rocker arms and rocker arm geometry than meets the eye and is more critical than you realize and just as critical as choosing the right LSA for your camshaft based on the setup as theres alot more to choosing a proper camshaft than meets the eye too........,,.


Screenshot 2022-12-19 014350.jpg
Screenshot 2022-12-19 014409.jpg


The difference between running pushrods tht are .100" too short is a loss difference of 23hp and 31ftlbs of torque plus the torque dropped off faster with the shorter pushrods too..........

IMG_20200930_121535478.jpg


Valve2.jpg

Screenshot 2022-12-06 125805.jpg


Good Luck
 
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Boostedpimp

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stage 1 cam requires some timing... 12 degrees isn't going to do it and I would definitely think about running a better octane fuel than 87 with that combo.
 
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General karthief

wonder how much it would cost to ship you a pair
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OP might be a tad bit overwhelmed with all these responses.
i agree, he ain't gonna change his push rod length to get better gas mil or install a set of heads with a better spark plug location, something as simple as changing the shift points and what gear you select for cruising speed will help, I drove my stang fairly hard and got 10+- mpg.
Not 'lugging' the engine around in 5th gear can help more than you think.
KISS!
Keep it Simple Stangers.
 
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Noobz347

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The [good] thing here [if you can call it that] is that I'm fairly well convinced that it's mechanical and not electrical.

I have to resist shotgunning what I think it could be cuz well... There's dudes in this thread already that know that stuff better than I do and I'd just be spitballing.
 

PonyGTrider

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Feb 27, 2019
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My carbureted 1989 gt convertible with an E303 camshaft and 3.73 gears got a verified 26mpg on the highway cruising at 72 mph. It got better mileage than almost anything we've owned. So, I'd say, with modifications, you can beat the factory fuel ratings published for our mustangs.
Wel that is nice to hear that. Good for you, it is not always possible to have performance and efficiency but will try reach a compromised point.
Thanks for sharing
I did not read every line but I take it we're no further along?

I saw some talk of octane rating... With your setup N/A, I'd run 89 non-ethanol straight for two tanks and take accurate measurements.

That aside, it may be time to invest enough equipment to data-log from a wideband O2 meter.


This approach is going to tell the tail even if the car doesn't want to spill the beans. :O_o: (I know, that was horrible)
Thank you,
For now I will just keep checking my fuel consumption the topically way, but absolutely agree with you on data logging at least my A/F ratio. For this I’m thinking on installing a dual wide and gauge to monitor both banks for easier and more accurate tuning
 

PonyGTrider

Active Member
Feb 27, 2019
189
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Mexico
The lobe sepration of the camshaft and the pushrod length are important too...Twisted wedge heads although say works with stock pistons really doesnt as you want the flame kernel dead middle on the piston and non-dished pistons with pistons below deck height cannot achieve such a task.....


Plus on street engines to maximize efficiency you need atleast 10:5:1 compression and the pistons shuld be flush with the deck or a max of .045" out of the hole to help with flame kernel shape too...

IMG_20220424_154128.jpg


A longer stroke and longer rods help alot too because with longer rods and larger stroke it alleviates the thrust stresses on the piston tops that shorter strokes exhibit...A neutral balance helps out heaps too...My 410w idles and runs as smooth as a european made engine....

I built a 347 stroker and put a Vortec V1 and of course it was tuned as anything built out of the normal needs to be tweaked especially the MAF transfer but once everything was tuned and Wideband 02 controller hooked up I was getting 18mpg...........

In the twisted wedge instructions on the last page theres this and a thing most overlook also to mention theres alot more to rocker arms and rocker arm geometry than meets the eye and is more critical than you realize and just as critical as choosing the right LSA for your camshaft based on the setup as theres alot more to choosing a proper camshaft than meets the eye too........,,.


Screenshot 2022-12-19 014350.jpg
Screenshot 2022-12-19 014409.jpg


The difference between running pushrods tht are .100" too short is a loss difference of 23hp and 31ftlbs of torque plus the torque dropped off faster with the shorter pushrods too..........

IMG_20200930_121535478.jpg


Valve2.jpg

Screenshot 2022-12-06 125805.jpg


Good Luck
Thank you,
Very important and useful details. This is a good reminder of the details we've missed specially on valvetrain geometry. I will try my best to double check those fine details.
I appreciate your help
 

PonyGTrider

Active Member
Feb 27, 2019
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stage 1 cam requires some timing... 12 degrees isn't going to do it and I would definitely think about running a better octane fuel than 87 with that combo.
Thank you,
I will consider your suggestions. I've noticed a lack of low end power with the 10* initial timing and will make the proper adjustments to fing a sweet compromised settings.
 

PonyGTrider

Active Member
Feb 27, 2019
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OP might be a tad bit overwhelmed with all these responses.
Thank you,
:) Overwhelmed? Not really , I understand everything that has been shared. The problem happen when I (Or a few of us for that matter) overlook some key details when we install or measure the valvetrain or stroke dimensions. Believe me I understand all that has been share here and will act accordingly with my engine conditions.
 
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Noobz347

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Wel that is nice to hear that. Good for you, it is not always possible to have performance and efficiency but will try reach a compromised point.
Thanks for sharing

Thank you,
For now I will just keep checking my fuel consumption the topically way, but absolutely agree with you on data logging at least my A/F ratio. For this I’m thinking on installing a dual wide and gauge to monitor both banks for easier and more accurate tuning
A/F ratio [and] rpm at a minimum. You would discover quickly that it's otherwise useless.
 
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PonyGTrider

Active Member
Feb 27, 2019
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i agree, he ain't gonna change his push rod length to get better gas mil or install a set of heads with a better spark plug location, something as simple as changing the shift points and what gear you select for cruising speed will help, I drove my stang fairly hard and got 10+- mpg.
Not 'lugging' the engine around in 5th gear can help more than you think.
KISS!
Keep it Simple Stangers.
Thank you,
Don’t discount me from replacing my pushrods if I revise my valvetrain geometry and find out some abnormalities. Maybe not replacing my heads but what if I decide to smooth out the heads intake runners and blend those bowls. You know, little things that add up for better performance. So it is ok with me if anyone shares their knowledge.
Thanks guys
 

PonyGTrider

Active Member
Feb 27, 2019
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I agree, I would like at least to know at least what is my mixture at idle and under load. I think it will be very useful.
Thank you
On another note I think I understand what you say that that could be a waste. So I will evaluate my situation. Because where I live we don’t have the luxury of a dyno tuning, which really sucks!

Thanks again
 

PonyGTrider

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Feb 27, 2019
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On another note I think I understand what you say that that could be a waste. So I will evaluate my situation. Because where I live we don’t have the luxury of a dyno tuning, which really sucks!

Thanks again
Have to say that I still have really lawsy MPG despite all the changes I've made. Today I checked my mileage again and got 7.73 miles to the gallon, and started a new test but this time I went back to my stock 55mm MAF tube and sensor and reset the ECU, will find out if I see any changes.
 

PonyGTrider

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Feb 27, 2019
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Here’s an update on this issue. I removed the 70mm MAF tube and sensor and installed the stock 55mm MAF tube and sensor.for a new MPG test and the results were astonishing. Filled up my tank took my odometer reading. Spent almost the whole tank and refilled again with 13.3 gallons and compared the latest with my previous odometer reading and…
Latest reading: 9,459.5 miles
Previous one: - 9,231.4 miles
Miles ran: 228.1 miles
228.1 \ 13.3= 17.15 miles per gallon

So did 70mm MAF tube and sensor decreased my MPG by 50%? Same driving habits and all…


At this latest refill will start the test again to confirm or debunk my numbers, but 50%??? I’m stumped!

Comments? Suggestions on these results?
 
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Monkeybutt2000

Mustang Master
Aug 11, 2019
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Here’s an update on this issue. I removed the 70mm MAF tube and sensor for a new MPG test and the results were astonishing. Filled up my tank took my odometer reading. Spent almost the whole tank and refilled again with 13.3 gallons and compared the latest with my previous odometer reading and…
Latest reading: 9,459.5 miles
Previous one: - 9,231.4 miles
Miles ran: 228.1 miles
228.1 \ 13.3= 17.15 miles per gallon

So did 70mm MAF tube and sensor decreased my MPG by 50%? Same driving habits and all…


At this latest refill will start the test again to confirm or debunk my numbers, but 50%??? I’m stumped!

Comments? Suggestions on these results?
Sounds like the sensor was bad.
 

KRUISR

5 Year Member
Apr 16, 2015
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Bad sensor or wrong sensor as Mustang5L5 said above in post #21 - needs to be the A2A version of the Crown Vic MAFs, not the OPs AA version.

I'm a C&L guy and have had no issues with both 73 and 76mm units running 19s and 24s. Just a tube change.
 
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