expected power gains ohv light mods

[OFG]

Considering an aluminum tube air intake with washable filter(mac intake?). Also considering a bigger mass air flow unit and throttle body. Might as well have the local muffler shop weld up a 3" cat back system with a turbo muffler later on. So, what kind of power increase can be expected from all these mods? What size is the stock MAF from a 99 sport ohv? Will there be driveability problems from these mods? Some street cars get a check engine light with these type mods. Suggestions to get around 190 hp or more from my trusty old ohv greatly appreciated. Thanks!

 

[RiverRat]

Don't think you will see any worthwile gains with those mods. How about a more "agressive" gearing and keep the 'ol 4.0 tuned up.

 

[Rhett]

If you get a chip along with all of that, you can dyno more hp. One person here with a 4.0 OHV had chip, TB, headers, MAF, exhaust, intake and dynoed at 189 hp. I think that's a high dyno but that's what he reported. At the wheels of course, it would be much less. Compare that with 160 hp stock. Irregardless of the numbers, if you do all the easy bolt on mods you will notice a difference...

 

[KEbert]

A 2.25" or 2.5" exhaust is plenty big enough for the ohv. When you increase the size too much and you lose all back pressure, the lower end power and torque will actuallly decrease. Think of it as water flowing through a garden hose. A smaller amount of water will travel faster through a smaller hose than a larger one. However, a large amount of water, which would be your higher rpm's, will travel faster through a larger diameter hose. So we find a happy median between the two and use a 2.25" or 2.5" exhaust pipe. I have 2.25" and I actually noticed a slight loss of power on the bottom end of the power band. It depends on your driving conditions and habits.

Save the TB and MAF until you have done more of the preliminary mods such as intake, cat back, and a chip. With these three mods you should have a significant amount of increased power and they are the cheapest of mods to do as well.

Look at the KKM intake too. I dont think a full alluminum intake is necessary, but eliminating the air box and using a large conical filter such as the KKM works very well. I'm extremely happy with mine. Good luck to you and keep us posted.

 

[Bottomlesspit]

I have a 99 OHV too. I came over from the modified Mustang scene, so I know a bit about tuning those cars...and am learning a bit about the Explorers now.
The types of gains from parts on the mustang don't quite add up to the gains from parts on my Explorer. With that said...I thoroughly enjoy working on the Explorer and the parts swaps have been fairly easy.
I added a Gibson cat back exhaust (2.5"), a BBK 66mm throttle body, the KKM air induction, and the Apten chip. Along with a few other cheap mods, I can feel a power increase. Mind you, I am not pinned back in the seat, but driveability and overall performance is a lot better. I enjoy driving the Explorer a lot more than before the mods. It just feels smoother, solid acceleration, shifting, etc. It's not a lot of increased power, but enough that I can tell the difference.
I think the best thing is how solid the engine feels. The small power increase is nice, but not the overall factor.
Just play with some of the common mods...read and search threads on this site about OHV mods. Don't have false hopes and dreams of drag racing your buddies in their stangs and camaros, just work on making your Explorer drive solid and fun.
Good luck,
Ken

 

[jimbo74]

i wouldnt do a 3" on a v6.....

2.25" or 2.5" is the biggest you should go

 

[TheRookie]

While you do make a valid point KEbert its for the wrong reason. Back pressure is ALWAYS your enemy. Flow however is what you are talking about. Your pipe analogy stands but the benefit is scavenging. High flow speed scavenges the spent gasses out of the combustion chamber.

 

[ipozestu]

Rydinhigh reported ~164RWHP with those mods. The quoted 160hp is not RWHP that is at the crank. Expect any where beteen 15-22% drive line loss. That puts him 30+ hp with addition of mods. He did have an apten. This really brings all the mods together.