Discussion in 'Wet behind the ears??' started by buzzin frog, Aug 8, 2018.

  1. buzzin frog

    buzzin frog Member

    I don's actually own a Buick but have started the search for a Skylark because I need something more fuel efficient to drive every day and I cannot bring myself to buy anything newer than a 1975 vehicle. I have a 1972 Chevy K20 that I have been daily driving for 7 months and a 1970 C10 torn down to the frame so I am not a total newcomer to classic vehicles.
    300sbb_overkill likes this.
  2. pbr400

    pbr400 68GS400

    Welcome from Georgia! Good luck with the search.
  3. gsfred

    gsfred Founders Club Member

    Welcome from NY. Posting you location may help in finding a car in your area.
  4. 2001ws6

    2001ws6 last of the v8 interceptors

    Welcome aboard! :cool:
  5. Nailhead Ronnie

    Nailhead Ronnie Life's 2 Short. Live like it.

    Welcome I'm a fan of the 64-69 skylarks.
  6. buzzin frog

    buzzin frog Member

    Thanks for the warm welcome. I'm in Bucks county Pennsylvania. I put a post in the cars wanted section with more information.
  7. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Welcome from SE Michigan!
  8. Nailhead Ronnie

    Nailhead Ronnie Life's 2 Short. Live like it.

    So you want good gas mileage? Are you shopping for a v6?.
    Any one know the mpg or an a body with a Buick v6?
    Or mpg of a v8 300 or 350? Did they put 340's in Skylarks?.
  9. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    You can only get so much out of a brainless carbureted v6 in a pre-'76 car without over straining it.

    He would do great with a '64 Skylark with a sbb 2bbl 300 and swapped in a 200R4 trans and a 3.42:1 rear gear. The car would be fun to drive and would have a 2.2914:1 final over drive ratio with a engine that has enough low end torque to chug along at such a low RPM in such a light car in O/D @ 45 mph.

    With a solid running well tuned sbb 300 with a 2bbl with the above swapped in he could possibly eek out up to 30 mpg on the highway with that combo. I would guess around 15 to 20 city depending if the car is on a road that lets him lockout the converter @ 45 mph? Speeds under 45 mph before O/D won't do as good because of the gearing but really not that bad.

    The same as above but only with a 700R4 trans, a 3.08:1 rear gear can be used that will have slightly better 1st gear take offs than with a 200R4 and also a better final drive ratio @ 2.156:1. Driving at lower speeds in the city if one could keep there foot out of the throttle with that pulls like a freight train first gear, in drive with 3.08:1 may do slightly better than the 3.42:1 rear gear from light to light. Possibly a couple more mpg highway driving as well.

    The 700R4 will need the driveshaft shortened or what I did was get one that was close from the junkyard and figured out what conversion U-joints from Napa to use to make it work. My '64 with a 700R4 got 15 mpg city with a non-lockout 2,200 to 2,500 stall(IIRC) converter and around 25 mpg on the highway. My car had a sbc Vortec 305(bought the car setup with a sbc 283/powerglide, I had the 305 and 700 sitting there so....wish the factory sbb 300 was still in it when I bought it) in it with a crappy 1406 Edelbrock 4bbl carb. This was with a 3.73:1 rear gear, man was 1st gear fun with drag radials! To bad I didn't get a chance to try that combo with a lockout converter! The car did low 14s like 14.2s in the QM setup that way, IIRC also had like low 1.8 60 ft times too with that freight train 1st gear. Had the car weighed @ 3,400 lbs on a gravel pit scale if anyone was wondering?

    Wish that car wasn't so rotted, the gas tank fell out of the car while driving the QM @ Milan Dragway(best ET of the night dragging the gas tank!)!:oops::D:D Luckily it stayed connected to the fuel line and I was able to put the tank in the trunk and reconnect the fuel line through a rot hole in the trunk to drive it home.:eek: Good times!

    Already having an old truck, swapping in one of the mentioned transmissions would help the OP's truck get better fuel economy if that's all the OP is looking for? Better gearing goes a long way for better fuel economy as expressed above. Not sure what engine is in his truck but if it has a sbc 307 in the '72 then the engine is probably working to hard for the weight of it? But still a 700R4 would be helpful to get it moving better from a stop and get better mpg driving it. A sbc 383 setup for low end torque with a 700R4 bolted to it with a 3.08 or 3.07 rear gear would get similar results as my '65 Impala in my signature below. If the truck has the sbc 307, that engine can be upgraded to have better performance/economy with some bolt on parts to increase low end torque. A set of 305 Vortec heads, Vortec aluminum intake, 600 cfm 4bbl carb, and a COMP Cams Xtreme Fuel Injected Camshafts 12-464-8;

    Found one on eBay for $199 vs $280 @ Summit;

    You don't need fuel injection to get great results with this cam and with 305 Vortec heads on if you have a sbc 307 use 1.5:1 self centering rockers because those heads have press in studs, this will keep lifts a bit lower so the heads won't need screw in studs. The springs will need to be upgraded to handle that lift, but if the head cores are sourced at a junkyard it shouldn't hurt the wallet to much to have that work done. While they're there you could even get the screw in stud conversion so you can run the 1.6:1 rockers that the cam above wants if that's in your budget?(still way less than buying a whole car)

    PM me if you want more tips to get more mpg out of your pick up.
    Nailhead Ronnie likes this.
  10. Mike Trom

    Mike Trom Blah, Blah, Blah

    68-72 Skylarks came with an in-line 6 and 1 bbl carb. I had two of them but I can't remember what type of gas mileage they got, probably not great.
    Nailhead Ronnie likes this.
  11. pbr400

    pbr400 68GS400

    Anything will beat an early 70s K20 (his current driver)!
    Nailhead Ronnie likes this.
  12. buzzin frog

    buzzin frog Member

    Wow, I did not expect this much feedback on an intro post. I know that an older car will only do so well in the mileage department, so I would be happy with something that averaged 15 mpg between city and highway driving. I think I could get there with a number of different engines as long as the gearing is right. The only possible problem will be getting a manual transmission that fits and still keeps the RPM's low. It may seem like a strange requirement but every time I drive someone else's car with an auto I find myself reaching for the clutch pedal and shifter and just being dissatisfied with the driving experience.
    I think my truck could get better mileage than the 9 its currently getting but I am still learning how to properly tune it (I'm only 23 and it is the first vehicle I've driven on the street with a carb). It currently has a Goodwrench 350 with headers,intake, and 750 vacuum secondary carb,SM465 transmission, 4.10 gears and 33" tires. I'm planning on adding a GearVendors overdrive at so me point so that will likely help tremendously. The link below has a picture of the truck if anyone is interested. I would put the picture in this post if I could get it to work. I know that I did not set it up for good gas mileage but I like it and its fun to drive anyway.
  13. wkillgs

    wkillgs Gold Level Contributor

    Here ya go. Easiest way to post pics is to just copy and paste. I cropped the background away.
    Cool truck!
    pbr400 likes this.
  14. pbr400

    pbr400 68GS400

    To maximize the economy of any vehicle, you want to burn as little fuel as possible to get the job done. Before spending big money on overdrive, make sure your rods and jets are what the factory recommends for the truck (if it’s a qjet). Also, if it’s a qjet and you don’t know its history, you may want to have it gone through by one of the guys on the board, and tell him you’re seeking efficiency. You might want to use O2 sensors to check your a/f ratio and tune the carb that way, especially if it’s not a factory carb. Edelbrocks especially are fat out of the box. (And make sure you’re in good tune, vacuum advance works, no vacuum leaks, etc.). This advice also fits for the car you buy.
    Nailhead Ronnie likes this.
  15. buzzin frog

    buzzin frog Member

    I have a Holley on it right now and honestly doubt it's possible to get the mpg much better given how unaerodynamic it is and the heavy, aggressive tires I put on.
  16. Nailhead Ronnie

    Nailhead Ronnie Life's 2 Short. Live like it.

    A quadrajet will get better mpg than a holly.

    Nice truck. Just to add. I had a car that was automatic with a v8 and it never let me down in the speed department, when i wanted more out of it, it would have way more to give.. something was done right and i credit my friend for setting it up so i put my 2 cent on the automatic transmission, they are fun.
    Last edited: Aug 10, 2018
  17. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    There's your problem right there!

    8.5:1 compression 195 HP to move that thing is WAY under powered! That engine has to work harder(use more fuel) to get that thing moving because of how under powered it is.

    Get a set of sbc 350 Vortec heads and the cam I listed for you above, the heads have smaller 64cc chambers than the 76cc smog boat anchor heads that came with the badwench engine that should get you to around 9.5:1. That cam and those heads will get you to around 330 HP and around 360 ft lbs.

    With the extra power the engine won't have to work as hard because it will make more power in every RPM right off idle with the cam I listed in the other post. Adding the gear vendors to the badwench without increasing the power output will lug that underpowered engine and you probably won't see much mileage improvements.

    Here's an aluminum head alternative ready to bolt on that should make around the same power as the Vortec heads would that you can use the intake and valve covers you already have;

    I don't think the badwench engine is a roller block so you'll need the retro- roller lifters for the cam I listed earlier;

    And you can get these rockers;

    The above are sweet rockers and very reasonable for the price but for a lesser expensive alternative;

    The above ones are on sale, looks like a good deal they got going for those.

    That Comp cam makes power from idle to 5,000 RPM and will still pull to 6,000(at least it does in my 383), with a gear vendors O/D it will make enough power to propel your truck @ 1,500 RPM in O/D without lugging the engine down.

    Around $1,000 dollars in engine upgrades to almost double the power that will increase mileage(if you can keep your foot light) is a great upgrade.

    My '65 Impala's aerodynamics are equal to a brick, slightly better than your truck and it gets 15 city and over 20 on the highway with the 700R4 O/D trans with an 850 double pumper Holey carb(have to have a light foot when driving it to get those numbers, sometimes hard to do:eek:). You should get similar or possibly better results with the gear vendors O/D and a good tune?

    If you're not good with tuning a carb why learn when you can get a self learning FI system for under $800;

    Or if you want to stick with the carb and learn how to tune it, get an air/fuel gauge so you can dial that thing in. And watch some YouTube videos on how to tune your carb, this alone will probably get you a couple more mpg if your tune is off a bit. You'll want to learn how to curve your distributor as well will be helpful for better performance and economy.
    Nailhead Ronnie likes this.
  18. Nailhead Ronnie

    Nailhead Ronnie Life's 2 Short. Live like it.

    Good stuff big bro!

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