4.0 SOHC Long tube headers | Page 2 | Ford Explorer Forums - Serious Explorations

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4.0 SOHC Long tube headers

I've been doing a lot of research on headers. I was told to go with shorties. Others say shorties will do nothing. I've read on some mustang boards that shorties will do nothing, and that long tubes is the way to go with the 4.0 SOHC. In all my research I've came to the conclusion that no one knows what the hell their talking about with headers on a 4.0 SOHC. That being said, I was planning on going with Gibson shorties, however, if long tubes are the way to go then maybe I should try these instead? We need some darn clarification here. What headers work for the 4.0 SOHC? The cast manifolds can't be the best thing for this engine. What makes this engine so much different that any other engine. Why will the headers not equal a gain for the SOHC? Need some answers here that make sense. Not opinions, true facts. Has ANYONE tried long tube headers on the 4.0 SOHC? If so, let me know what you think. Anyone know of anyone that tried this?

No I'm not, this isn't gonna work.

By the way, MAC says 18HP with there mustang shorties..hehehehehehhee

Okay - I may of did something stupid. I've got these MACs on order. oh heck, what have I done now....

I canceled the order. This is NOT going to be a good idea for my future goals. Thanks, James...

It's helpful to remember that any dissipation in exhaust restriction would be best aided by a lessening in intake restriction...that's why Joe shmoe who throws a K&N on his ride and expects to go rocketing on down the track will likely be sorely disappointed. I played this game in high school and didn't get it until I got into the higher maths and physics...It's funny when you see the Toyota commercial running right now where they tout the excellence of the factory shorty headers that they use on the (???) Tundra, while their intake tract has the aerodynamic efficiency of John Wayne's large intestine. Love to see if the rest of the engine was tuned around them, tho (they do weigh less, at the very least)...
Eventually when you boil it all out you get down to the camshaft; therefore, you can start there and work out, or start at the outer end and work in; regardless, it all has to work together, or you may wind up with negligable power gains.
This always does not hold true, however. Some cams are naturally better than the rest of the breathing mechanism, and some intake and exhausts that rock are hampered by a cam that's designed for Grammy Smith. Ever see a 76 Duster 360? Dump the intake and exhaust and you're in the 13's with minimal cash outlay.
When considering the difference, other than weight, the difference is akin to the difference between a rifle and pistol. Everything varies by degree, but this is a decent generalization, at least as far as my stupid physics textbook says. What does everyone else think? What makes the difference with the 4.0, for instance? Intake, exhaust, valve timing/duration, or what?

Spinnn - The intake and exhaust are good things to do to the 4.0 SOHC as many have done and shown increases in HP and torque. The header debate (long tubes vs. shorties) that you see me going back and forth on in the thread was a result of me over thinking the entire thing. I mean, it's a stock 4.0 SOHC, the difference between long tubes and shorties will be VERY small. You can just about say this for any v6 with stock internals in my opinion. Yes, there may be differences but they're not too much. It's known that long tubes give you torque down low and shorties bring the HP at the top end. I don’t have any scientific information that I’ve personally overseen but the info is out there. All and all it's close with a stock engine.

As far as cams go there are not many options for us SOHC guys. If I was to put the money in the engine like this I would defiantly use some sort of simulation software to do the homework for me. I will not buy or guess a cam grind without some sort of proof of what it'll do with my combo. But then you quickly realize you could get enough power to shatter the engine by force feeding it with a turbo or supercharger. So for the cost you can't beat just increasing the boost pressures on the 4.0 SOHC.

My advice if you want to experiment is to get a hold of a simulation software like Desktop DYNO and play around with different cam grinds or any other combo you may dream up.