Hey guys before you roll eyes just hear me out. I’m in San Diego which has $4-5 gal gas. I must have the most fuel efficient setup. I’m currently running a stock 327 that smokes and burns oil. All that jazz you know my story. I don’t care about going fast . Would it be possible to install an inline 6cyl that’ll bolt right in the same mounts and bolt up to 4 speed Muncie? I heard they get 20mpg. Thanks let me know if this is a bad idea
I'd change the ***le from V6 to inline 6 to avoid a lot of negative comments... I can't tell you specifics but obviously that car was available with a 6 cylinder engine, so there are provisions to install one. I would imagine you need different mounts, and the radiator gets moved forward to the 6 mounting points.
The inline 6 will not bolt up to the same mounts. You need a 2 barrel 283. Mine got 20 mpg on the highway. That 6 can't do much better.
A good health 250 6 will be 16ish to 20ish , then there gear ratios between Factory v8 & 6 . Burning oil , more likely valve seal's ! Can be replaced with out R& R engine . Guide could be over warn , can be checked also Rope & piston up on compression stroke , Back yard check or Machinist .. care needed to know so you do not Drop valve down p*** head into Bore , then head needs to be removed .. First do if not done yet do a Leak down test , More then a compression test , A well tuned stock 327 2 or 4 barrel 18 plus mpg unless hills every where
Here gas $3.00 gal , 2 of my rides 10 mpg on High test About $4.00 gal Yes & no , 283 smaller bore & stroke. Stroke might be same , I do not know off top of my head but I'm sure others will chime in.
I did this compression check sept ‘24. I took it to a shop to get it checked out in December. The said I need a new engine or rebuild. Supposedly they did a compression check and leak down but I never got the results. It burns about 1qt oil every 200mi.
A fresh 327 with 63cc heads, a mild cam, & 3.08 -3.36 axle would be capable of 20 mpg quite easily with the right jetting.
Not a leak Down test The one with 129 , worn rocker , worn push rod , worn cam , stuck ring . Carbon on valve seat . Leak down & alittle more diagnosing the 129 can just be a bad check ..
The 63 came with a 230 and in a Biscayne with a 3 speed OD could get over 20 mpg on the road and 16/17 in town. Your Impala is heavier and will get less, it’s just physics. From experience a 250 will get less if restored stock. It will need some messaging and proper parts to match a 230 on milage.
Many of us are trying to save you time and money we can sort fill you out, No disrespect that you're kind of new to this & my Communication and writing is ""Terrible!!!!
308,336 is that the rear differential? The jets are you talking about the carb? It’s got a Carter wcfb 4bbl. I do have a brand new Edelbrock 500cfm that I want to install but need a proper manifold.
Yes & Yes jets , the Eldelbrock I believe needle rods as jets , You can get an adapter to make it work It's not the best choice but you're not building a hopped up/ race engine
That Impala has a certain drag coefficient, certain drive train resistance, and a certain weight. Those 3 things determine a cars fuel economy. None of those 3 things change significantly if you swap from a 327 to an Inline-6 or any other motor. In other words you need some amount of Horsepower to push the car through the air at a certain speed. In order to maximize fuel economy you need to produce that amount of horsepower as efficiently as possible. That means operating near peak torque as much as possible, having as high of a compression ratio as possible, and keeping the fuel mixture as lean as possible. Those rules are the same no matter what engine is under the hood.
The compression isn’t terrible, not ideal but should be drivable, might improve with driving. Might need a refresh or rebuild. I’d fix that engine before swapping in a six. Depending on what’s wrong might be cheaper. Dan
I put 20w/50 oil in it. Also marvel mystery oil, Lucas oil stabilizer. I’m just trying to help it best I can for now.
Sure it's possible, but I don't think you're going to gain any MPG with the swap. My '57 Chevy actually gained 3 mpg with a swap to a V8, although that was a 235/Powerglide coming out, so part of that was gaining a gear and the 235 was never considered a super efficient engine. Gear ratio is going to matter more for MPG than a swap to an inline 6, that and engine tuning. 20 is possible with a V8.
Physics are Physics. Car, Airplane, Tug Boat, Rocket Propelled Bar Maid. It doesn't matter. If you are that worried about $5 gas, start researching Brake Specific Fuel Consumption and work backwords.
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