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I just wanna first say hello to everyone as I'm new to the forum. I've searched around and found a little info here and their, but felt I still should just post and ask.

My daily driver is a 1984 Chevy Caprice Classic Wagon. Stock. 4100lbs. Computer Command Control QJet 305 sbc. 700R4 transmission. 235/75/R15 rites. 2.43 open rear end. The engine is worn out. It pops out the exhaust at stop lights once warmed up. Leaks and burns oil. It just needs to be put out of its misery.

I want to build a "budget" 350 vortec engine for this car. I know I'll have to install a torque converter lockup once I ditch the computer. A buddy of mine already has the stuff for that from another project. What I am wanting is suggestions as far as a cam, intake and carburetor to go for. I do tow some cars on a tow dolly here and there so I'd think torque would be somewhat important. It is a daily driver, about 40 miles a day for work. If I could get 20mpg I'd be ecstatic. Some people have said to go with a Lunati VooDoo cam. But I don't know if that would be good or bad, or even which one to get.
I plan on replacing all the rings, barrings, gaskets and seals. I'm kinda planning on just lapping the valves to save cost.

So if anyone has any suggestions or ideas, please fell free to share them. It's been about 12 yrs since I last built an engine and at that time money wasn't a factor... but then it wasn't a daily driver.
 

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isthe 350 is a vortec engine..
or are you building a 350 with adding the vortec heads??

I'd use the ccc q-jet if you need to pass emissions
if not a non computer q-jet..

the truck vortec cam would be a good match for this.. as it sounds like a towing vehicle.. not a hot rod..

an all new vortec 350 is 2000.oo give or take..
 

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Emissions isn't an issue here. The engine will be a junkyard pulled Vortec 350 from a late 90's truck or van.
 

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Replace the intake with a vortec carb intake, stab in an HEI, add a non-ccc Qjet. Done.

Look to ebay and craigslist for intakes. If you look for an Edelbrock intake for vortec heads, it will cost $250 because its special. But there were zillions of GM intakes put out there for marine applications and on crate engines.

Hundreds of people buy the crate engine and swap the intakes, so there are sometimes new, take-off vortec carb intakes for pretty cheap. The same intake was used on carbed Vortec marine engines. I used to have a couple but sold them.

Edit: Forgot something... most Vortec truck engines don't have provisions for a mechanical fuel pump. Add a cheapy electric 5 psi Carter bubble pump and you're in business.
 

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X2 on using the Q-jet, they really are a good carb for mild engines and will give you the best gas milage of most any other aftermarket carb. I dont think I could ever rebuild and engine and put a stock cam back in it but "to each his own". The voodoo line may have more aggressive ramp rates then what you are looking for. here is my suggestion:

http://www.summitracing.com/parts/hrs-180225-12/overview/make/chevrolet

You hopefully reuse all the other factory valvetrain, although you may need to replace some of it. Most of those vortec engines can simply be freshened without having to by any major hard parts.
 

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I think these guys are missing the OP questions and he said the wagon had a 305 in it and he wanted to build a vortec 350 to install......
personally I would just go get a crate engine , like the 400 HP vortec 350 from year one. and call it a day
 

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Wrench Turner
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I wouldn't recommend the VooDoo cam,or,a Comp Extreme type cam.They make good power,but,not really something you want in a daily driver,or,for towing.The Ramjet cam(#14097395) would be an upgrade to the stock Vortec cam.The ZZ4 cam would also work well for your usage,but,you would need to either have the heads machined for a higher lift cam,or,use a set of beehive springs with the ZZ4.Either of these cams will deliver smooth power/torque & be quiet & easy on the valve train.I highly recommend you have the heads magged for cracks before spending any money on them & using new springs.The Ramjet cam will put you in the 320 HP range,while the ZZ4 cam would get approx. 350 HP with 4 bbl carb,headers,& a good exhaust system.
 

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Wrench Turner
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That Ramjet cam can be bought off Ebay for $129 & does have a fuel pump lobe.The ZZ4 cam runs approx. $200.If the engine you buy is high milage,(over 200,000),I would use new roller lifters.Skip White sells new Delphi rollers for $100.Performer RPM intake & 4 bbl of your choice.
 

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To reach your economy and cruise goals with that 2.42 rear gear, stick with the stock Vortec 350 cam or Ramjet 350/HT383 camshaft.

A carbed Vortec 350 even bone stock will put plenty of smiles on your face when you hit the gas when compared to your stock carb 305.

peace
Hog
 

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I just wanna first say hello to everyone as I'm new to the forum. I've searched around and found a little info here and their, but felt I still should just post and ask.

My daily driver is a 1984 Chevy Caprice Classic Wagon. Stock. 4100lbs. Computer Command Control QJet 305 sbc. 700R4 transmission. 235/75/R15 rites. 2.43 open rear end. The engine is worn out. It pops out the exhaust at stop lights once warmed up. Leaks and burns oil. It just needs to be put out of its misery.

I want to build a "budget" 350 vortec engine for this car. I know I'll have to install a torque converter lockup once I ditch the computer. A buddy of mine already has the stuff for that from another project. What I am wanting is suggestions as far as a cam, intake and carburetor to go for. I do tow some cars on a tow dolly here and there so I'd think torque would be somewhat important. It is a daily driver, about 40 miles a day for work. If I could get 20mpg I'd be ecstatic. Some people have said to go with a Lunati VooDoo cam. But I don't know if that would be good or bad, or even which one to get.
I plan on replacing all the rings, barrings, gaskets and seals. I'm kinda planning on just lapping the valves to save cost.

So if anyone has any suggestions or ideas, please fell free to share them. It's been about 12 yrs since I last built an engine and at that time money wasn't a factor... but then it wasn't a daily driver.
OMG 4100 pound Station Wagon, build it as a 383 you'll be glad you did.

Gas mileage and VooDoo cams don't meet in the same sentence.

The heads, pistons and cam must be a matched set that is you want as much dynamic compresson as the fuel you want to use will hold without detonation, plus you want good gas mileage. That means an effecient chambered head like the L31 Vortec but there are many and better options including aluminum which allows more compresion than cast iron. A very good choice in cast iron is this thing from EQ look at the chamber pictures and remember that as you look at other heads be they aluminum or iron. EQ has this nuts on correct. EQ Cylinder Heads 23 Degree Answer To The Crate Debate In The IMCA | OneDirt

The pistons need to be D dish. The dish size along with the chamber, clearance and gasket volumes will establish the Static Compression Ratio. The flat area of the piston establishes the squish/quench activity which you want as high as you can get especially with a daily driver turning low RPMs at cruise (give or take about 2000 revs). This produces good mileage, low emissions, and lots of torque. The cam establishes the Dynamic Compresson Ratio based on how much piston stroke is use up when the intake valve seats in crankshaft degrees. This is "trap pressure" which while measured in compression ratio is the thermodynamic funtion of the engine, you want this to be about but not less than 8 to 1 with smog heads, 8.5 with L31's the EQ's can push 8.7 all of these for iron heads. For aluminum the DCR can be .5 to 1.0 ratio higher depending on weight and final drive ratio. More weight and or higher drive ratios need to err to the lower side, light weight and stiff gearing can tolerate the high side. A wide LSA 112 or more is preferable for gas mileage as this reduces overlap. Overlap initiates intake flow before the piston goes over TDC good for making power, but kills gas mileage as a portion of that inital intake flow just goes out the exhaust unburnt, bad for emissions, power and mileage. The head's combustion chamber comes into this, those heads that feature a beak extending between the valves directs some of the incoming mixture away from the exhaust valve keeping more of the initial intake flow inside the cylinder. Same thing can be achieved on a regular head by sinking the exhaust valve, but that brings other problems.

Use 6 inch rods no matter what, they slow the acceleration changes of the piston which reduces vibration effects on the crankshaft, side loading of the piston skirt and to a tiny extent buys a little more breathing time as the piston goes over TDC. These things make a smigen more power but mostly help reduce blow-by and frictional losses by stabilizing the piston thus the rings relative to the cylinder wall. These also go a long way toward being able to build a 383 or 400 with internal balance without adding Mallory metal to crank, such are the geometry advantages of long rods.

Ditch the 2.43 axle too high to run efficiently with an overdrive transmission. Get a 3.08 in there it'll actaully cruise on less throttle.

Bogie
 

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If it was me I'd take a hard look at how you're going to drive this barge. If its mostly around town kinda stuff; I'd go with a 3.23 rear gear or even 3.42. This will mean less throttle input to get the Bismarck under way from a stop. Couple that with the overdrive, and it'll drop the engine RPMs down enough to make things happy. Id also add an auxiliary trans cooler (make sure its plumbed properly). There is a GM Vortec takeoff manifold on flEa-bay for $99 but if you're into Facebook groups, or Craigslist; there are bound to be some cheaper. Id also search recent threads as there is a great discussion on dual plane intakes, and Jegs makes a killer one, in the Vortec pattern for good money P/N 513002. The only downside to the Jegs; is that its "Square Bore" only - ie Holley carb.
 

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If it was me I'd take a hard look at how you're going to drive this barge. If its mostly around town kinda stuff; I'd go with a 3.23 rear gear or even 3.42. This will mean less throttle input to get the Bismarck under way from a stop. Couple that with the overdrive, and it'll drop the engine RPMs down enough to make things happy. Id also add an auxiliary trans cooler (make sure its plumbed properly). There is a GM Vortec takeoff manifold on flEa-bay for $99 but if you're into Facebook groups, or Craigslist; there are bound to be some cheaper. Id also search recent threads as there is a great discussion on dual plane intakes, and Jegs makes a killer one, in the Vortec pattern for good money P/N 513002. The only downside to the Jegs; is that its "Square Bore" only - ie Holley carb.
Very good points on gearing.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

I had a 1989 Caprice with the 305 TBI 200R4(0.67:1 vs. your 700r4 with 0.70:1 OD). I ran a shorter tire than your 27-28" tires with the stock 2.43 gears.
Over a 1200 km trip the car averaged 26 mile per CAN gallon multiplied by 0.83 to get US MPG makes it 23mpg.

Anything other than 120kph(75mph) cruising the car was geared to high. Remember that my car was a TBI vs your carb. The off idle torque was excellent with this engine, but any sort of incline required a manual pull down from OD to D to maintain speed WITHOUT the use of greater throttle application. I surmise that with some lower gearing, say a 3.08 or 3.23 gear would be best for highway cruising or a 3.42 for city-highway mix.


Since you do tow cars which effectively double that weight, a set of 3.73's might be best.
Right now you are revving 1425rpm to maintain a 70mph speed in OD.
rear gear changes net the following 70mph cruise rpm assuming all your current specs
1600rpm=2.73:1
1810rpm=3.08
1900rpm=3.23
2015rpm=3.42
2200rpm=3.73
2300rpm=3.90
2425rpm=4.10
2525rpm=4.30
2675rpm=4.56:1



A newer GE-III 5.3 geared correctly could net even better fuel economy. It would bolt to your trans, you could even use a carb intake and an ignition control box which would allow you to run various timing curves and keep the OEM Coil Near Plug(CNP) ignition intact.

peace
Hog
 
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