305 vs 350

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Frankenchevy

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What is that? Is that the fake gasoline that rots out all rubber gaskets and fuel line?
not if you're fuel system is replaced with e85 compatible stuff, lol. that's what I did, but at my compression ratio it's not really beneficial. I did it because all our gas has 10% ethanol now.

however, they did an episode of engine masters on it. the hot rod guys like it because the octane rating allows them to run their hotrods around that used to run exclusively on VP115 or c14+ @$16-17 a gallon. now they can fill up at shell with their 12.5-14:1 compression engines @ $2.50 a gallon and drive around to their hearts content. they said it's like having race gas out of the pump at 87 octane prices.
 

Jrgunn5150

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not if you're fuel system is replaced with e85 compatible stuff, lol. that's what I did, but at my compression ratio it's not really beneficial. I did it because all our gas has 10% ethanol now.

however, they did an episode of engine masters on it. the hot rod guys like it because the octane rating allows them to run their hotrods around that used to run exclusively on VP115 or c14+ @$16-17 a gallon. now they can fill up at shell with their 12.5-14:1 compression engines @ $2.50 a gallon and drive around to their hearts content. they said it's like having race gas out of the pump at 87 octane prices.

Locally to me, it's 1.45 a gallon, and I can run 15psi without a single care on it.
 

Frankenchevy

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you probably have a dollar per gallon less in taxes than Cali. thank you Jerry Brown.
 

4WDKC

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not if you're fuel system is replaced with e85 compatible stuff, lol. that's what I did, but at my compression ratio it's not really beneficial. I did it because all our gas has 10% ethanol now.

however, they did an episode of engine masters on it. the hot rod guys like it because the octane rating allows them to run their hotrods around that used to run exclusively on VP115 or c14+ @$16-17 a gallon. now they can fill up at shell with their 12.5-14:1 compression engines @ $2.50 a gallon and drive around to their hearts content. they said it's like having race gas out of the pump at 87 octane prices.

Its not very common here or i would have probably converted my vette and the efi on it.
 

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What part don't you understand Derrick? I'm happy to explain..
Pane was equally popular in Canada as the US in the early 90s. It was a fraction of the cost of gasoline. Problem was the dual fuel conversions.. never worked right. The timing is different from gas to 'pane, so dual fuel was a terrible compromise.
IMO 'pane is far superior but hard to find stations that pump it, and the tanks are a drag if you don't have the room.
1 how the hell do they fill them is it a weight thing or gallons. 2 does the tank look like a propane tank or gas tank. 3 does it still use a carb or how does the air mix with the fuel (LP).
 

crpntr78

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305 too small? Try running an 8600 GVW K25 with a 292!! Now that's under powered! Had an 84 GMC set up that way. Manual trans to boot.
 

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1 how the hell do they fill them is it a weight thing or gallons. 2 does the tank look like a propane tank or gas tank. 3 does it still use a carb or how does the air mix with the fuel (LP).
The tanks come in various size and shapes. Just that they are much heavier metal than a regular gas tank. Propane for auto is sold by the litre, and pumped in under pressure. Barbecue propane is sold by weight.
There is a mixer with your engine coolant flowing through it so the expanding propane (when it meets air) does not freeze closed. From there into a propane 'carb' like an Impco 425. The system self regulates. Engine vacuum determines how much 'pane is released. It's super easy to deal with. If it's too lean it doesn't over heat, just doesn't produce power. Too rich will over heat, but it's very obvious when it's too rich because smells very strong!
 

Derrick

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The tanks come in various size and shapes. Just that they are much heavier metal than a regular gas tank. Propane for auto is sold by the litre, and pumped in under pressure. Barbecue propane is sold by weight.
There is a mixer with your engine coolant flowing through it so the expanding propane (when it meets air) does not freeze closed. From there into a propane 'carb' like an Impco 425. The system self regulates. Engine vacuum determines how much 'pane is released. It's super easy to deal with. If it's too lean it doesn't over heat, just doesn't produce power. Too rich will over heat, but it's very obvious when it's too rich because smells very strong!
thanks
 

bucket

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Boat anchor vs. 350. I think most of us pick 350 more power. only thing is if you want gas mileage you might want to think about the 305.

Just like many other people here, I've daily driven these trucks, with everything from a 250 to 454's. The 350 is always the better option in this case. And you can always get similar mpg from a 454 too. Remember you are pushing a brick through the wind.

They never should have put a 305 in these trucks. The trucks are too heavy. You don't actually get better mpg with less cubes, you just get an overworked, under powered engine.
My 383 on propane uses the same amount of fuel as my 'pane 305, but has a lot more power!

Exactly.

305 too small? Try running an 8600 GVW K25 with a 292!! Now that's under powered! Had an 84 GMC set up that way. Manual trans to boot.

That's not underpowered, just slow. That's a near bulletproof combo too.
 

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I forget the code for the truck 305, but it probably gets the silver medal for the types of 305s built. The heads on it are not bad at all, better than almost every other 305 head and some other 350 heads. I do agree, though, that they don’t really belong in the truck unless you did some pretty healthy upgrades, and doing stuff to a 305 is not as cheap or quite as universal as doing the same to a 350. I’d go with the 350 for sure, but with that said, the 305 doesn’t deserve all the hate it gets. I think if they wouldn’t have made the choked down emissions versions and would have kept them only for the types of trucks that would have come with a 4.1L, it wouldn’t have gotten such a bad rap. A K10 long bed should not have come with a 305, though.

I'll hit quote on your post but I seen I think shiftpro mention WeeOFives should have never been put in these trucks. I agree and GM probably does too. Being a smog tech in Cali back in the late 80's into early 90's I know a little about that. The code you mention was the LE9. The most common truck engine of the 80's in the GM light duty pick up fleet. 305 cubes with ESC (Electronic Spark Control), and in Cali emissions trucks they had CCC (Computer Command Control) system with feedback E carbs for AF mixture and such.

This is also when trucks started getting more of the taller gears like the 2.73 and 3.08, station wagon gears and the attempt at coming up with an OD transmission that was a flop riddled with problems. This was all done due to meet the EPA standards of avg mpg for the manufactures fleet, and reduced smog emissions. This is when Cat Converters were added to vehicles, Lead was taken out of fuel, and the manufactures to get there way underpowered engines by reducing compression, adding NOx (Nitrogen of Oxides) bumps in heads that are restrictive adding AIR (Air Injection Reactor) better know as smog PUMP, when it actually INJECTS air right at the exaust valve just as exhaust exits the head to create a reburn of the exhaust gasses. Without getting more technical, the EPA and US standards is why in the late 70 and into the 90s is why vehicles are so gutless. Technology is catching up finally and we've been getting our horsepower back over the last several years.

We bitch about our emissions and mpg requirements, Japan's have been way way worse for many many years. Anyone ever heard of these used engines for imports that have usually 40-50,000 miles on them and we can buy them here in USA? It's true. You can buy Honda, Toyota, Nissan and such engines used with 40-50,000 miles on them for about 1/3 the cost of a new engine. Alot of it has to do with meeting emission requirements in Japan. After so many miles, like a well broke in engine over there, it's getting a little carbon on the pistons, uses some oil, as in maybe a quart every 5000-8000 miles etc, it won't pass their emissions so usually it's cheaper to buy a new car than try to get it to pass emissions. Lots of good cars get **** canned in Japan.
 

Frankenchevy

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I'll hit quote on your post but I seen I think shiftpro mention WeeOFives should have never been put in these trucks. I agree and GM probably does too. Being a smog tech in Cali back in the late 80's into early 90's I know a little about that. The code you mention was the LE9. The most common truck engine of the 80's in the GM light duty pick up fleet. 305 cubes with ESC (Electronic Spark Control), and in Cali emissions trucks they had CCC (Computer Command Control) system with feedback E carbs for AF mixture and such.

This is also when trucks started getting more of the taller gears like the 2.73 and 3.08, station wagon gears and the attempt at coming up with an OD transmission that was a flop riddled with problems. This was all done due to meet the EPA standards of avg mpg for the manufactures fleet, and reduced smog emissions. This is when Cat Converters were added to vehicles, Lead was taken out of fuel, and the manufactures to get there way underpowered engines by reducing compression, adding NOx (Nitrogen of Oxides) bumps in heads that are restrictive adding AIR (Air Injection Reactor) better know as smog PUMP, when it actually INJECTS air right at the exaust valve just as exhaust exits the head to create a reburn of the exhaust gasses. Without getting more technical, the EPA and US standards is why in the late 70 and into the 90s is why vehicles are so gutless. Technology is catching up finally and we've been getting our horsepower back over the last several years.

We bitch about our emissions and mpg requirements, Japan's have been way way worse for many many years. Anyone ever heard of these used engines for imports that have usually 40-50,000 miles on them and we can buy them here in USA? It's true. You can buy Honda, Toyota, Nissan and such engines used with 40-50,000 miles on them for about 1/3 the cost of a new engine. Alot of it has to do with meeting emission requirements in Japan. After so many miles, like a well broke in engine over there, it's getting a little carbon on the pistons, uses some oil, as in maybe a quart every 5000-8000 miles etc, it won't pass their emissions so usually it's cheaper to buy a new car than try to get it to pass emissions. Lots of good cars get **** canned in Japan.
I have a spare JDM engine for my element sitting in my garage now. They pull them after 3 years because the inspections and upkeep become to burdensome and expensive. My spare k24 looks brand new inside and it was $995 complete.
 

Squarehead1984

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I wish I could invent a time machine and go back to the day that GM decided to put the 305 in trucks. The engineer would get slapped in the back of the head and then get a severe cussing!! Trucks deserve V8 power not this quagmire of an engine. Ford did the same thing with the eco boost. I don’t care if they make 450hp. They sound like ass. Even the ford engineers agree cause they emit v8 sound through the speakers. OK I’m done with that rant.

Check with jegs or summit. They have short blocks and don’t have a core charge. I THINK!!!
 

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