Gas Mileage Recommendation.... Yup.

impaloligist

New Member
Joined
Jun 3, 2016
Ok, So this is going to sound like a bad idea to some of you, but I am just starting to go through my engine that has been sitting for 10+ years waiting to be used. I am going to put it in a 1986 Cutlass. I have the GN drivetrain. I don't have a turbo, intercooler, intake pipes, chip and some other little dinky things to complete it (downpipe exhaust). Here are the questions/goals. I want a cool daily driver that gets Good Mileage and can smoke most $cumbags who think they're tough. Hear is what I'm gonna do automatically, Ported heads and intake (always buy the best heads and intake you can afford) small turbo (don't know what size yet) that will be ball bearing. EGR delete. Roller cam (I wouldn't build a 327 Chevy without one, so why compromise?)

I do have a choice of two lockup converters Stock Buick 1996 stall according to the sticker or 1211 stall Olds. No difference on highway, but might help mileage around town. Too low?

Any cam ideas? If this was a Chevy I'd consider like 206-210 @ .050 with a 111-116 LSA. I know there's the Comp 206-206, that seems to be a good off the shelf grind and states that could be used with stock converters.

I just wanted to know if that 206 is the way to go or should I be thinking 196-196 or less? Does that 206 cam affect the mileage in a negative way? Do stock Grand Nationals really get around 30 MPG (8.5 inch 3.42 rear end)? Or is that some crap I heard years ago?

Turbo? I'm going to use the stock manifolds and cross over pipe.

Will I go to the track with it? Maybe once every 3-4 years. If there is no snow, will I drive it when it's 6-10 degrees outside? Hell yeah. A/C? No. Oil cooler, no. Rainstorm during summer day @ 95 outside Yes. Cruise control? Maybe. Stock Cutlass 14 inch wheels with spoke hubcaps? Yes.

Does this kinda $hit keep me up at night? Yes.
 
Add a TB fuel tank and good fuel pump to the list of parts you need. Also an engine harness.
 
Ok, So this is going to sound like a bad idea to some of you, but I am just starting to go through my engine that has been sitting for 10+ years waiting to be used. I am going to put it in a 1986 Cutlass. I have the GN drivetrain. I don't have a turbo, intercooler, intake pipes, chip and some other little dinky things to complete it (downpipe exhaust). Here are the questions/goals. I want a cool daily driver that gets Good Mileage and can smoke most $cumbags who think they're tough. Hear is what I'm gonna do automatically, Ported heads and intake (always buy the best heads and intake you can afford) small turbo (don't know what size yet) that will be ball bearing. EGR delete. Roller cam (I wouldn't build a 327 Chevy without one, so why compromise?)

I do have a choice of two lockup converters Stock Buick 1996 stall according to the sticker or 1211 stall Olds. No difference on highway, but might help mileage around town. Too low?

Any cam ideas? If this was a Chevy I'd consider like 206-210 @ .050 with a 111-116 LSA. I know there's the Comp 206-206, that seems to be a good off the shelf grind and states that could be used with stock converters.

I just wanted to know if that 206 is the way to go or should I be thinking 196-196 or less? Does that 206 cam affect the mileage in a negative way? Do stock Grand Nationals really get around 30 MPG (8.5 inch 3.42 rear end)? Or is that some crap I heard years ago?

Turbo? I'm going to use the stock manifolds and cross over pipe.

Will I go to the track with it? Maybe once every 3-4 years. If there is no snow, will I drive it when it's 6-10 degrees outside? Hell yeah. A/C? No. Oil cooler, no. Rainstorm during summer day @ 95 outside Yes. Cruise control? Maybe. Stock Cutlass 14 inch wheels with spoke hubcaps? Yes.

Does this kinda $hit keep me up at night? Yes.

1. These don't get 30 MPG the way most of us drive them. I know I didn't buy the cars I have for gas mileage. If you're chasing gas mileage go with the smallest cam but the 206/206 is a great street cam. Those 14 inch wheels need to be at least 7 inches wide or you will be traction limited. You could run a taller rear end gear like a 3.08 or a 3.23 if you're that concerned about gas mileage. Then you can drive 65 mph with some real small injectors and try to get 30mpg. Many have been able to get mid 20 mpg on the highway and that is not unreasonable but I don't see the fun in that. I'm fine with 550-600 HP that gets 15 MPG average and that's 90 mph on the highway and many red light encounters on my way to and from work. I'm sure it could get 20 mpg if I could keep my foot out of it but isn't that the point in having it to begin with? If I wanted gas mileage I'd buy a Honda or a Toyota.
2. I wouldn't have a car without AC unless you live somewhere that is very cold all year and it doesn't sound like it @95 degrees.
3. Even with your heads done you need a converter that will stall at least 2000 rpm and that's with a stock sized turbo. You can find a good converter that matches whatever turbo you want to buy just get a lock up since you are wanting gas mileage. If you're saying you have the stock D5 converter or one that stalls at 1996 RPM you will want to keep the stock turbo or one very close to it. A 1200 rpm converter will make your car a dog don't put that in a turbo car.
4. Even if you think you will be happy with this combo that gets 25 mpg, once you go fast you just want to go faster and then you end up buying bigger turbos, injectors, converters, intercoolers, exhaust and etc. then soon you will not care about MPG it's an addiction.


Sent from my iPhone using Tapatalk
 
Ok, So this is going to sound like a bad idea to some of you, but I am just starting to go through my engine that has been sitting for 10+ years waiting to be used. I am going to put it in a 1986 Cutlass. I have the GN drivetrain. I don't have a turbo, intercooler, intake pipes, chip and some other little dinky things to complete it (downpipe exhaust). Here are the questions/goals. I want a cool daily driver that gets Good Mileage and can smoke most $cumbags who think they're tough. Hear is what I'm gonna do automatically, Ported heads and intake (always buy the best heads and intake you can afford) small turbo (don't know what size yet) that will be ball bearing. EGR delete. Roller cam (I wouldn't build a 327 Chevy without one, so why compromise?)

I do have a choice of two lockup converters Stock Buick 1996 stall according to the sticker or 1211 stall Olds. No difference on highway, but might help mileage around town. Too low?

Any cam ideas? If this was a Chevy I'd consider like 206-210 @ .050 with a 111-116 LSA. I know there's the Comp 206-206, that seems to be a good off the shelf grind and states that could be used with stock converters.

I just wanted to know if that 206 is the way to go or should I be thinking 196-196 or less? Does that 206 cam affect the mileage in a negative way? Do stock Grand Nationals really get around 30 MPG (8.5 inch 3.42 rear end)? Or is that some crap I heard years ago?

Turbo? I'm going to use the stock manifolds and cross over pipe.

Will I go to the track with it? Maybe once every 3-4 years. If there is no snow, will I drive it when it's 6-10 degrees outside? Hell yeah. A/C? No. Oil cooler, no. Rainstorm during summer day @ 95 outside Yes. Cruise control? Maybe. Stock Cutlass 14 inch wheels with spoke hubcaps? Yes.

Does this kinda $hit keep me up at night? Yes.
Smallest/closest to stock cam I'm aware of is speed pro 194/204 part# cs1112r. It was recommended to me by Richard Clark back in 05, he was using that cam for his stock rebuilds back then, its a flat tappet so maybe consider having it & the lifters cryogenically hardened prior to install & plan on running amzoil zrod oil for protection. Try messaging Steve V here, he is finishing up my car and might be able to give you some insight as to how it performs with champion irons. I'm using a bb te44 & tight 2600ish l/u converter to match the small cam.
 
1. These don't get 30 MPG the way most of us drive them. I know I didn't buy the cars I have for gas mileage. If you're chasing gas mileage go with the smallest cam but the 206/206 is a great street cam. Those 14 inch wheels need to be at least 7 inches wide or you will be traction limited. You could run a taller rear end gear like a 3.08 or a 3.23 if you're that concerned about gas mileage. Then you can drive 65 mph with some real small injectors and try to get 30mpg. Many have been able to get mid 20 mpg on the highway and that is not unreasonable but I don't see the fun in that. I'm fine with 550-600 HP that gets 15 MPG average and that's 90 mph on the highway and many red light encounters on my way to and from work. I'm sure it could get 20 mpg if I could keep my foot out of it but isn't that the point in having it to begin with? If I wanted gas mileage I'd buy a Honda or a Toyota.
2. I wouldn't have a car without AC unless you live somewhere that is very cold all year and it doesn't sound like it @95 degrees.
3. Even with your heads done you need a converter that will stall at least 2000 rpm and that's with a stock sized turbo. You can find a good converter that matches whatever turbo you want to buy just get a lock up since you are wanting gas mileage. If you're saying you have the stock D5 converter or one that stalls at 1996 RPM you will want to keep the stock turbo or one very close to it. A 1200 rpm converter will make your car a dog don't put that in a turbo car.
4. Even if you think you will be happy with this combo that gets 25 mpg, once you go fast you just want to go faster and then you end up buying bigger turbos, injectors, converters, intercoolers, exhaust and etc. then soon you will not care about MPG it's an addiction.


Sent from my iPhone using Tapatalk
Do small injectors help with mpg? I asked this question once in a 42 vs 60 thread and was told the only thing that will affect mpg is your right foot :confused:
 
Use a thin head gasket and mill the heads a little. The bump in compression will increase your MPG.


Sent from my iPhone using Tapatalk
 
I want a cool daily driver that gets Good Mileage and can smoke most $cumbags who think they're tough.
Raise the compression ratio.
Use the stock cam or smaller.
Only smooth out the intake ports. Don't increase the volume of the intake ports any more than is necessary to get the ports smooth. Increased velocity.
Use the smallest injector at the highest pressure that you can get away with.
Use an engine management program that allows for lean cruise.
Use gasoline that contains no alcohol.
Use the EGR.
 
Any variant of a cam that adds any amount of overlap more than stock will reduce fuel economy. Increasing the compression ratio to about 9.25-9.5:1 and using a roller cam with similar overlap @ .050" as stock and lean burning around 15.5:1 will help. Additionally using thin piston rings with tight fitting hypereutectic pistons and running the engine up around 200* can increase economy. Using low rolling resistance narrow tires will also help. A stock GN gets about 24mpg on a highway cruise at 55mph. Not 30mpg


Sent from my iPhone using Tapatalk
 
I've got cams with -19 @ .050" if needed


Sent from my iPhone using Tapatalk
 
You won't be smoking anyone if your primary concern is fuel economy


Sent from my iPhone using Tapatalk
 
This one works for me every time and it is relatively in expensive. Let your wife drive,;) my cars always get the best fuel mileage when my wife drives them. BUT they are the most fun when they get the worst fuel mileage :D
 
I appreciate the responses. I thought I replied yesterday but must have done something wrong.

4. Even if you think you will be happy with this combo that gets 25 mpg, once you go fast you just want to go faster and then you end up buying bigger turbos, injectors, converters, intercoolers, exhaust and etc. then soon you will not care about MPG it's an addiction.
That's what I have the Black Cutlass for. Fun.
you will want to keep the stock turbo
I will gave to use one close to stock, since I don't have one.
I wouldn't have a car without AC unless you live somewhere that is very cold all year and it doesn't sound like it @95 degrees.
A/C doesn't work i any of the cars now. I used to work in a powerhouse. It was a little warm 140* on the fan floor.
I've got cams with -19 @ .050" if needed
19 degrees of overlap? Or 190"s in the duration @.050?
A stock GN gets about 24mpg on a highway cruise at 55mph.
That' fine. Better than what I'm getting now with the Caprice. Don't know about the S-10 yet we're planning a gear change on it. If that works out maybe I'll slack a little on the 3.8 mileage quest. The S-10 will be ready first.
I'd buy a Honda or a Toyota.
Nope. At this point I'm not even running anything newer than 1990. Maybe I'll step it up for a new diesel truck in the near future.
You won't be smoking anyone if your primary concern is fuel economy
Hopefullly, they won't know what hit 'em. But, stock GN's do move pretty good don't they?
 
One thing I should mention here is that I'm the kinda dude that just doesn't worry much about things. For example if the 200 overdrive BFR trans goes, don't think I won't hesitate to put in a Tremec 5 speed. If the trans ever goes in the black Cutlass, 8L90-E and done. The Ford doesn't have a radio or A/C, neither did the gray Cutlass, the Caprice only has an AM/FM radio and no working A/C.
 
The good news is that with the small turbo, cam, tires and injectors your transmission will last a long time.


Sent from my iPhone using Tapatalk
 
If I wanted gas mileage I'd buy a Honda or a Toyota

Nope. At this point I'm not even running anything newer than 1990.

No need to spend money on a new car and support foreign car companies to get 30+ mpg.
A 1987 Buick Lesabre (non T-type) gets 30+ while running 1450 rpm at 55 mph.
The Lesabre T-types had a higher gear ratio for more performance and still got 28 mpg while running 1650 rpm at 55 mph.

Although any more, profits go over seas to some degree.
I'm still trying to convince my wife NOT to shop at china-mart (walmart).
 
Okay. So I disassembled the core and found the it should probably be rebuilt The mains do have some scoring on them. No ridges though. Also #3 has a score on the bearing but the crank journal looks and feels good. So I reassembled it hand tight. I only pulled the first 3 main caps anyway. I did not remove the rear cap, as I saw what needed to be seen. Is RPE still doing Buick 3.8 short blocks? Any ideas on how much? I will also consider suggestions. I do have an engine down at Pat Musi's shop. But not sure if he'll do the 3.8. I'd have to call him.
 
I'm still trying to convince my wife NOT to shop at china-mart (walmart).
I only buy oil there. It is just repackaged. Meets API requirements.


You know, If I was inclined to use flat tappet hydraulic lifters, I just picked up my NOS Reed cam from the floorboard of the #1 Impala SS. 210-205 duration.
 
Top