Looking for suggestions: more power from a 2.9

[19Walt93]

My friend wants me to work on his 86 Ranger 4x4, 2.9, 5 speed. He wants more power but wants to keep the 5 speed and functional 4 wheel drive. A 302 would probably shred the transmission, the 7.5 and maybe the transfer case. He was thinking of using a 2.3 turbo but I think he'd be better off with lower gears and either some minor mods to the 2.9 or a 4,0 ohv swap. He's going to get me the axle code so I can see if there's improvement to be made there. Opinions please, what would you do to a 2.9 to get a power increase without a complete overhaul and machining, or would a 4.0 swap be the way to go?

 

[rusty ol ranger]

@PetroleumJunkie412

 

[PetroleumJunkie412]

SO. MANY. THINGS.

How far down does he want to go with it?

Very easy motor to raise compression in with little negative effect.

2.8 flat tops take it from 9:1 to 10: compression.

Forged can take you higher.

Camcraft makes cams.







However.

The EEC-IV is by FAR the biggest achillies of that engine. Simple microsquirt and tune will push that thing WAY ahead of where it is now.

His cam is probably shot, too. The soft cam rumors were true, sadly.

 

[Uncle Gump]

I would just make new friends...

 

[19Walt93]

I have friends who drive GM's and Toyota's, too, so I'm not going to dump him for owning a 2.9. I thought a 4.0 ohv swap and some deeper gears would give him enough of an increase to notice. He doesn't have an unlimited budget and can't do much of it himself.

 

[rusty ol ranger]

I have friends who drive GM's and Toyota's, too, so I'm not going to dump him for owning a 2.9. I thought a 4.0 ohv swap and some deeper gears would give him enough of an increase to notice. He doesn't have an unlimited budget and can't do much of it himself.

Unless hes towing the 4.0 isnt gonna "feel" much better then a 2.9.

A set of 4.10s to replace the 3.73s (im guessing) is probably going to give you the most bang for your buck.

Also id go through and "diagnose" the 2.9 (compression check, codes ran, etc) and make sure its giving him 100%

Also being an 86 its got a knock sensor which can retard timing and make it a turd if hes got lifter racket.

The 2.9 is a tempermental little bastard. They'll keep running even when they shouldnt...but theyll run like shit. When mine had a plugged EGR and bad injectors 5th gear was worthless but it still didnt "feel" bad, just nutless any other time.

Point is, make sure its tip top before you go gutting it for a marginal increase with a 4.0

 

[RonD]

My friend wants me to work on his 86 Ranger 4x4, 2.9, 5 speed. He wants more power but wants to keep the 5 speed and functional 4 wheel drive. A 302 would probably shred the transmission, the 7.5 and maybe the transfer case. He was thinking of using a 2.3 turbo but I think he'd be better off with lower gears and either some minor mods to the 2.9 or a 4,0 ohv swap. He's going to get me the axle code so I can see if there's improvement to be made there. Opinions please, what would you do to a 2.9 to get a power increase without a complete overhaul and machining, or would a 4.0 swap be the way to go?

When you change engine size then you need to change computer and wiring, and in most cases the transmission as well

The 2.9l and 4.0l used the same trans bolt pattern which made this an easier swap, still need to swap computer and wiring, but 1986 transmission wouldn't like the extra torque, so trans change to M5OD-R1 4WD would be best, 1350 transfer case is fine to use and will bolt to the M5R1

But as said power gain is not 0 but not all that much for the work involved

V8 swap is the same work, engine/trans computer and wiring, but you can drop EFI and use carb setup so no computer and wiring, and can use V8 manual trans with V8 transfer case, could use 1350, but better to use V8 transfer case

7.5" rear end is fine to use, with any engine, its the tire size that is more of the issue with rear end size, if going over 32" diameter tires then Explorer axle would be best, it has larger axle diameter, Ranger 7.5" and 8.8" use same size axles

Turbo is better for 2WD than 4WD, on road power, 4-wheeling is not often high speed travel, it can be but.......lower RPM torque is more practical

Building the 2.9l up for more power would be an option but would still be better off changing to M5R1 transmission
And as said you can't really run a "built" 2.9l with factory computer
The 1986 computer is a "speed density" system so can't add more fuel for more power its pre-set to run the factory 2.9l
And it gets expensive to run 3rd party EFI computers

For 4WD I think the V8 would probably be the best choice, if rebuilding the 2.9l as stock, is not what he wants
"There is no replacement for displacement"

 

[19Walt93]

This is the kind of information I was looking for. It's hard to imagine a 4.0 wouldn't feel more powerful than a 2.9, though. His transmission whines in every gear but 4th so I assume it's a Mazda/TK. What vehicles would a M5OD-R1 be found in? Later Rangers, I would guess? He does have 3.73's so a switch to 4.10's would be my first recommendation regardless what else we do.

 

[PetroleumJunkie412]

E fan shouldn't be underrated as well... Idk what it is about the fan design on the 2.9, but that thing sucks down more than it should.

 

[RonD]

M5R1 4x4 trans was first used in 1990 Rangers with 4.0l, there were earlier 2WD versions used in Rangers starting in 1988

1986 4x4 will have FM-145 or Toyo Kogyo 5-speed

Whinning in all but 4th on a 5-speed means input shaft gear is starting to go, its not used in 4th, well has no stress on it in 4th

 

[19Walt93]

I was assuming it's the TK transmission because of the whine. The Mitsubishi tans didn't usually whine, the teeth usually broke off the reverse gear and left you with 2 neutrals. How late was the M5R1 used and,if it was used with the SOHC, is the bell housing pattern the same?

 

[rusty ol ranger]

SOHC is a different pattern slightly. So up to 99 or so you would be good finding a direct bolt in.

The general TK failure point is the input bearing, so yes its probably a TK, assuming its the original trans the door code will be a "5" if its a TK

 

[RonD]

M5R1 from 4.0l SOHC 4x4 would work on the 2.9l, or 4.0l OHV 4x4, and 1350 transfer case will bolt to it
so 1990-2011 4.0l 4x4 trans would work

 

[19Walt93]

Thanks, that opens up some possibilities.

 

[bobbywalter]

insert dumpster pic here......




































dumpster full of 4.0's!!!!!


yeah......you thought i was movingup the list again didnt ya!.....well no..... not this time...