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If I take my car to work, 14 mile round trip, it costs roughly $20 depending on how much mixture of 110 I have. I try to have 75% or better. I get about 6 mpg on the back carb, front doesn't kick it much (still babying it). I use the 110 because it's available and I can somewhat afford it. I got the new C/S which gets better mileage. Even though, it doesn't matter much what the mileage is, it's a blast driving around.
I just got fuel for my 442- Cam 2 at $8.49 per gallon !!!!!!!!
Its a SBO Bored to 4.130 with custom Diamond flat tops, stroked .100
Custom rods with a 330 steel crank. Around 373 ci
Edelbrock heads with FAST EFI
Designed and machined by ANDY MILLER.
Fired it up this weekend.
Runs strong and loud !
455 for sure same amount of money, keep it pump gas friendly. Do research think and figure what you want, a wheel stander off the line, a Olds that will run down the road, ride in a parade, without coughing, gagging and overheating. Then have it built locally same with tranny and axle. If you have them built outside your area where shipping is involved, you have zero warranty, not a hand shake and not even a kiss. I built a 455 keeping 93 octane friendly, 342 gears and turbo 400. We put 20.00 bucks in the tank and take a ride in the mountains, a car show and maybe lunch. Perhaps this helps with your decision making and remember keep it between the lines...
As I have said before. The older oldsmobiles have the aerodynamic of a Brick Wall! Just fighting the air, the faster you go, it multiples. 1987 Cutlass highly modified 350. 2004R 3.73 rear. 27.2 tall rear tires. With adjusted speedo gear. Carefully not opening the Rochester Quad secondaires. I can hear them start to open up. I can get between 18 to 20 on the highway. Around 2.8 mpg with a very heavy foot. I guess you can put a two barrel on the engine to save gas.
My 88 Cutlass, 24 mpg Imperial on a long highway trip. That is a 73 350 with shorty headers, 2.5" exhaust and 3.42 gears with 26.3" tires. The 70S with a 9 to 1 214/214 cam 350, 2004R and 2.78 gears with a 25" tire, 19 mpg Imperial on a long highway trip. With a 260, 2 mpg improvement in both cars, not worth it.
Wow old thread, with out sounding like a smart *** don't know don't care, 1956 Olds Super 88 324 4bbl have no Idea what the rear end gear ratio is, I'm just happy as a pig in sh/t when I get in turn the key and she comes to life and I back her out the garage for her weekly errand runs,
puts a big ole smile on my face as I leave the driveway !!!! I do however understand the curiosity on MPG maybe some day I will figure it out.
I do know with premium fuel now running $3.69 per gallon she's getting more expensive to drive.
My daddy always said there are three things you don't tell.
1. Where you go to get the best squirrel hunting.
2. Where the best ***** in town lives.
3. how much gas mileage your car gets.
Many years ago, feeling that my Q-Jet had lost a step, I took my '68 4-4-2 into what was then reputed to be the best tuneup/carburetor shop in town to get a carb rebuild. When I got it back, the car was bog-slow; I don't even think the secondaries were opening at all. I wheeled it right back into the shop:
"Hey, my car is really slow now. Can you fix it?"
"Well, sure, but your gas mileage is going to go all to hell."
It was about then that I decided to learn how to rebuild a carburetor myself.
Wow old thread, with out sounding like a smart *** don't know don't care, 1956 Olds Super 88 324 4bbl have no Idea what the rear end gear ratio is, I'm just happy as a pig in sh/t when I get in turn the key and she comes to life and I back her out the garage for her weekly errand runs,
puts a big ole smile on my face as I leave the driveway !!!! I do however understand the curiosity on MPG maybe some day I will figure it out.
I do know with premium fuel now running $3.69 per gallon she's getting more expensive to drive.
On my 55 324 I get just about as lousy gas millage as the A bodies, long trips I averaged about 13 city and highway combined.
Solly does your car ping on the cheap stuff? If you haven't tried it try the next lower grade. I run 87 all the time with no issues but a 55 has a little lower compression than a 56, could make a difference...Tedd
Tedd,
I have never heard a knock or ping, however I have only really pushed it once or twice and It's had only premium fuel since I have owned it.
I pretty much drive it like a old fart !!!
1970 Cutlass with 463 c.i. and a Ck performance 200R4, 3200 lock up converter, 3.91 Gears, 27.2 inch tall tire. Cruising at 70 mph I have gotten up to 17 m.p.g.
I get 21 mpg in my 96 98. That's mostly highway driving. If I drive more in the city it goes down to 19-20. Who knows what kind of mileage my 71 98 gets?
Only had my 76 98 Regency for about a month now, but did a couple preliminary checks.
Came up with 19mpg out on the highway running 65 to 70mph, and looks like just under 12mpg running around town.
Remember this is a 455 with a 4 barrel pushing almost 5,000lbs down the road.
I can live with that!
Was getting 9 mph. Jetted primary down and changed front rods on quadrajet and now get 11 mpg, but at a small cost. With air on I was at 190 water temp and now at 210. I have the progressive ignition and at cruise speed 2400rpm I have timing at 34 total. Does anyone know if changing timing up or down at cruise speed will lower water temp. Idle, vacuum and acceleration are fine. Just looking for experience on cruising speed timing.
Thanks to I will try tomorrow is it will be another hot day in Phx. I will go up to 40 total at cruise and watch temps.
Progressive ignition? Is this a programmable ignition system?
Your timing set at 34 is probably ideal at WOT. You could easily add another 10-12 degrees at cruise. Just make sure it goes back to 34 under heavy throttle.
Keep bumping up the cruise timing until you hear a touch of spark knock with the A/C on, hot outside temps, about the worst possible conditions. Once you find the timing where the engine rattles, take out a couple degrees and you should be good. If it won’t rattle and ping under the worst conditions, it won’t under ideal conditions. Keep in mind occasional light pinging isn’t a big deal, as long as it stops once you start applying some throttle.
Progressive ignition? Is this a programmable ignition system?
Your timing set at 34 is probably ideal at WOT. You could easily add another 10-12 degrees at cruise. Just make sure it goes back to 34 under heavy throttle.
Keep bumping up the cruise timing until you hear a touch of spark knock with the A/C on, hot outside temps, about the worst possible conditions. Once you find the timing where the engine rattles, take out a couple degrees and you should be good. If it won’t rattle and ping under the worst conditions, it won’t under ideal conditions. Keep in mind occasional light pinging isn’t a big deal, as long as it stops once you start applying some throttle.
Thanks. That is the answer I was liking for. I will go up at cruise speed and leave the wide open throttle grid area timing alone.
From 34 to 40 degrees timing. It is not hot out today so next week will be the real test on water temp drop. If 40 degrees is not enough I can keep going higher.
Keep adding timing until you get some light pinging under mild throttle, then back off a few degrees. I wouldn’t be surprised if the engine likes 45-48 total. As long as the timing goes back to the 34 degrees under heavy throttle you have the best of both worlds
From 34 to 40 degrees timing. It is not hot out today so next week will be the real test on water temp drop. If 40 degrees is not enough I can keep going higher.
Okay, I'll assume you're talking total timing because I don't want to think about you melting piston crowns.
I agree with Matt on this one, add timing. You will be running very lean with that jetting, what number rods did you use? I usually run 38 to 40 with a 30 degree vacuum can off manifold vacuum, talking a low compression motor with a stock or mild cam. That equals nearly 50 at idle and almost 60 degrees at cruise! What compression ratio and cam do you have? On a 9 to 1 or better motor you need less vacuum advance or pinging will occur. I ran 22 base with 38 total in around 2600 with a 30 degree vacuum advance can on a 9 to 1 with a 214/214 cam . I had low speed bucking, the 20 degree can fixed it but lost some part throttle response. On a 9.6 to 1 motor with a 204/214 cam, I had to be very conservative or pinging occured. The new motor with 9.5 to 1 and a 218/218 roller cam, I may have to knock a couple of degrees of vacuum advance but I will be turning with a wideband. You having 2.78 gears, surprised your mileage is so low, is it an Ethanol blend gas?
Last edited by olds 307 and 403; May 24th, 2021 at 05:51 AM.
I'm set like your 24 degree with 38 total. In by 2700. The progressive ignition is fully adjustable timing at the entire rpm range. Motor is stock 2 barrel with swapped edelbrock performer card, 4 barrel intake a quadrajet. Cruising timing with vacuum set at 48 total. Yesterday in the heat with air water temps were 200 to 205. That is a 5 to 10 degree water temp drop.
The primary rods I could not read. The tip measured .006 and tapered nicely to .026.with a 68 jet. I'm happy with the changes so far and will keep adjusting timing to help wide open throttle response now.
You should be around 9 to 1 compression, the 204/214 Edelbrock cam should provide good mileage and decent power and allow pretty aggressive advance. Full full throttle, 38 to 40 is probably as much as you want but every motor is slightly different. Of course as you know, what feels good on the street, isn"t technically the fastest. 38 to 40 felt better flooring it around town but 36 always ended up fastest at the track for my Olds V8's
July 29th, 2012, 03:23 PM
