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  #13  
Old 12-16-2013, 09:49 PM
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Quote:
Originally Posted by Strongjeff View Post

i dont think its the design of the engine that causes the loss of tourqe in the 4.0. I think a lot of it has to do with the heads on the 4.0, i have seen plenty of inline engines benifit from headers. Also header design is very inportant
Your header deseign theory seems to be true. On both my F150 and my WJ, the stock manifold was pretty good. On both its a form of the "tri-y" type configuration. Except 3 into 2 into 1. However I don't think a portion of torque comes from the heads I think it's got to do with the fully vertical cylinders resulting in direct transfer of energy into the crankshaft. Where as V styles the cylinders are offset from the crank. Resulting in energy loss due to excess friction on the cylinder walls. This would explain why V's have to rev higher to obtain the same amount of torque. But this is just just a theory.
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  #14  
Old 12-16-2013, 10:05 PM
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Quote:
Originally Posted by 4.0_4x4 View Post

Your header deseign theory seems to be true. On both my F150 and my WJ, the stock manifold was pretty good. On both its a form of the "tri-y" type configuration. Except 3 into 2 into 1. However I don't think a portion of torque comes from the heads I think it's got to do with the fully vertical cylinders resulting in direct transfer of energy into the crankshaft. Where as V styles the cylinders are offset from the crank. Resulting in energy loss due to excess friction on the cylinder walls. This would explain why V's have to rev higher to obtain the same amount of torque. But this is just just a theory.
while it is true that the power curves will be different between an inline and a v setup, headers improve power by getting the exhaust out faster, thus making more power. Heads are part of the equation if not one of the most important aspects to make power. Example would be taking a 350 chevy engine and putting 283 chevy heads on it. You effectively increase compression and it will run like a 400 cid engine. Head design is key, as well as the combustion chambers, valves and runners in the head. I do agree with you on the fact that inlines last longer because of the fact there is less vibration in an inline. V engines dont last as long because they dont run smooth. The 4.0 & the 3.7 that replaced it make the same tourqe figures but the three seven produces 20 hp more. The four o will last longer even tho the three sev has a balance shaft to combat vibrations.
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  #15  
Old 12-16-2013, 11:10 PM
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i forgot to add that camshaft profiles play a major role in what shape the power curve has
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  #16  
Old 02-07-2014, 01:32 AM
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pffft.

Y'all are forgetting the basics:

Updated and balanced fuel injectors...do the fuel rail mod while your there.

Line pressure regulator

Tranny cooler

High stall torque converter

Gears
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  #17  
Old 02-07-2014, 02:33 AM
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Quote:
Originally Posted by DeucesALLin View Post
Y'all are forgetting the basics:

Updated and balanced fuel injectors...do the fuel rail mod while your there.

Line pressure regulator

Tranny cooler

High stall torque converter

Gears
I havent forgot the basics. The topic is headers N cams for greater performance. I have already upgraded my injectors and im shopping for gears now. Go look at my build thread.
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  #18  
Old 02-07-2014, 12:20 PM
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Re: Other Mods for greater Performance?????

I was referring to the thread in general... so sounds like I need to scope out your build.

I am thinking of looking for something like a Boost-a-pump and an aftermarket fuel pump. I went with the green 4 hole injectors, balanced. Looked legit, from an ebay guy. Manifold is being decked now, anyway maybe I should post a build thread too.
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  #19  
Old 02-07-2014, 07:32 PM
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Originally Posted by DeucesALLin View Post
I was referring to the thread in general... so sounds like I need to scope out your build.

I am thinking of looking for something like a Boost-a-pump and an aftermarket fuel pump. I went with the green 4 hole injectors, balanced. Looked legit, from an ebay guy. Manifold is being decked now, anyway maybe I should post a build thread too.
You should. Share the knowledge lol
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