351w torque build opinions please

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Old 04-28-2013, 08:13 PM
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351w torque build opinions please

I'm debating between a 351w and a 300i6 for my truck. If I go Windsor what kind of torque can I achieve low in the power band? like 2000 rpm. I'm talking fully rebuilt roller motor with
Performer rpm intake, 650 carb, Long tube headers, rv cam, aftermarket heads, ect. Im wanting a daily driver engine that runs on 87 octane and gets decent mpg. Is 18mpg highway doable? How much torque can I get? Id love 250-300hp as well.
Opinions please!
 
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Old 04-28-2013, 09:05 PM
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With EFI you can have 400tq from just off idle and 300hp with a pretty much stock build(GT40 heads + RV cam), a carbed version won't make quite a much TQ at 1000rpm but by 2k it will, good luck getting anywhere close to those numbers with a "stock" I6.
 
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Old 04-29-2013, 07:55 AM
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It would be carbed definately what kind of static compression ratio are we talking about for these numbers? Would a cheaper set of aluminum heads be better then gt40s? Say edelbrock performer rpms? I'd really love to run it on 87 octane.
 
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Old 04-29-2013, 09:02 AM
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The gt40 heads are a great low rpm head. You'll get the desired torque down low, but you'll use up the capacity of them early on.
If you had the money aluminum heads will benefit you because of the heat dissipation. You'll be able to run 9.5 compression easily on 87 octane. Iron heads I'd stick to low 9s with a lower total timing advance. The ethanol in the fuel is helpful in being able to run more compression. But I'd aim for 9-9.2 if going with gt40. Being carb you have a huge selection of cams.
If your truck is already a v8 I wouldn't even consider the 300-6. They have some support for go fast parts, but if you're going to spend money on it (there are no aftermarket heads I can think of) you'll get more hp increase for your money with a 351.
 
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Old 04-29-2013, 09:53 AM
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Stock vs. stock, I might choose the I6 but if your doing a full rebuild with aftermarket parts the 351w will be way better.
What truck is the motor going in?
 
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Old 04-29-2013, 09:59 AM
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Yeah that was with something around 9-9.3:1 compression ratio so it will be very pump gas friendly. Aftermarket heads will greatly increase HP potential making a 350hp/400tq build quite achievable but if you go beyond that in search of bigger horsepower low rpm torque begins to fall unless compression is raised
 
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Old 04-29-2013, 10:52 AM
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The truck is a 78 half ton shortbed 4x4. I think the drivetrain will consist of a ranger torque splitter, np 435, and np 205. 9 in and Dana 44 3.73 gears and a tire somewhere in the 31- 33" range. The goal is a reliable truck that can be a daily driver, do some mild offroading, and pull a pop up camper. Reliability, longevity, and fun to drive. 17ish mpg is what I'm Hopin for as well. You guys have me sold on the Windsor. I'm hoping to keep the cost of engine, rebuild, and performance parts around $4k. So what's the best aftermarket head on a budget for low end to midrange?
 
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Old 04-30-2013, 06:04 PM
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Since any aluminum head is going to be better then a pair of cast iron GT40's you only need to look for ones with smaller port volume and smaller valves then some other aftermarket head. A set of AL heads with 2.02 intakes and 205CC port volume will produce less torque at low RPM's then a head with 1.9 intake and a 185CC port volume all else being equal. That's not to say that you can't build an engine with the big valves and not make the same or more torque then the smaller valve head you just would use a different cam, compression, or intake.
 
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Old 05-02-2013, 10:12 AM
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Here's a graphic representation of what you can expect, low rpm torque can be boosted even more if you're willing to sacrifice a little o that top end horsepower.. maybe use the 35-234-3 instead.

 
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Old 05-02-2013, 12:11 PM
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So this is b asic ally what I can. Expect from a stock shortblock with the edelbrock top end kit?
 
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Old 05-02-2013, 03:41 PM
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Yep.. only additional thing would be pistons with valve eyebrows to clear those big intake valves.
 
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Old 05-29-2013, 10:05 PM
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I've got a buddy with a stroker mustang. He told me a stroker lower end is close to the same money aw a stock one. If this is true how would that graph look with a 393 stroker with a lower duration more torque oriented camshaft? How long lasting and reliable is a stroker compared to a stock displacement engine? Mpg is pretty much gunna suck with 393 co I suppose
 
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Old 05-29-2013, 10:34 PM
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A 393 with the Edelbrock topend will make 450+ ft/lbs across the board, and for truck uses there's no need for anything but a basic nodular iron kit so it's relatively cheap.. but there's often no need to replace the crank and rods on a stock rebuild so I don't see it costing the same. There's also no reason a stroker motor should have any shorter life than as a stock motor.
 
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Old 06-03-2013, 07:17 AM
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Can you show me the graph for a 393 shortblock with the performer rpm top end? Say 9.5-1 cr and a Holley 650 carb, smaller diameter long tube headers. Maybe try a few different cam profiles for me too if its not too much trouble.
 
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Old 06-03-2013, 11:52 AM
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I've also heared that a "long rod" 351w makes more torque and let's you run higher cr. Is this true?
 


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