m50d!

[AllanD]

I could care less about on road, I'm concerned with off-road, there are many times where you really need all the gearing you can get to navigate an obstacle smoothly.

Remember that you aren't simply going up 1.1liters,
but that represents a 38% increase in displacement!

For all effects and purposes the 4.0 is a 2.9 with the equivelent
of TWO extra cylinders!

there is no simple description in words that will explain the difference
you will feel with the 4.0 Vs the 2.9

People look at the 4.0's 225ft/lb Vs the 2.9's 170ft/lb and think
"wow 55ft/lb more", but that's at the two engine's respective
torque peaks.

Down low from 1200rpm or so up to 1700-ish the 4.0 is making
DOUBLE the torque that the 2.9 makes across much of that range.

The 4.0 really does make useable torque down at 1200

You want "smooth power" at low rpm offroad? by comparison to
a 4.0 a 2.9 is a peaky little bitch.
The 4.0 has a torque curve like nebraska.

a 4.0 feels far stronger compared to a 2.9 than the raw numbers
of peak output would indicate.

AD

 

[bigpotato555]

AllanD I sure does understand what your trying to tell. But after putting quite a bit in the 2.9l...don't want to put cash in a 4.0l....because I dream about a fuel injected 302...I guess I'll just put a gaz mask on and get the hell out of my centerforce.....goodbye 300$....but when there is no other choice you got to do it!!!

 

[AllanD]

AllanD I sure does understand what your trying to tell. But after putting quite a bit in the 2.9l...don't want to put cash in a 4.0l....because I dream about a fuel injected 302...I guess I'll just put a gaz mask on and get the hell out of my centerforce.....goodbye 300$....but when there is no other choice you got to do it!!!

Remember that after a topic has been repied to by several users the replies are not always aimed at the original poster.

My last reply was aimed entirely as Hahnsb2, who is concerned by the same gearing issue as you are, but will only get that gearing change when he swaps in a 4.0 engine with his 4.0 Mazda trans.
He's worried about losing that 9% of his gearing.

I'm just explaining to him that it's like worrying about an extra small rock
in the path of a tidal wave of extra torque at low rpm.

With your 2.9 if you were really concerned you could get
a 2.3 2wd organ donor trans and have all the parts you'd
need to convert your transmission to the wide ratio
configuiration.

But if you have definate plans for a V8 swap I'd recomend
living with it, because it ALL becomes irrelevant after swapping
a 5.0 and whatever trans you'll use with it.

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[Hahnsb2]

That's one thing I did forget to take into account is that the 4.0 will handle the lower RPMs much better than the 2.9.

 

[OldRedB2_84]

I plan on using a 2.9 m5od behind my 4.0, is this a wide ratio tranny?
If so what is it like? any pros and cons?

 

[rickcdewitt]

I plan on using a 2.9 m5od behind my 4.0, is this a wide ratio tranny?
If so what is it like? any pros and cons?

try reading this thread from the beginning,you woulden't need to ask

 

[AllanD]

I plan on using a 2.9 m5od behind my 4.0, is this a wide ratio tranny?
If so what is it like? any pros and cons?

Yes, it's a wide ratio trans but thare are a few subtle strength issues,
first it specifically related to the '91-up transmission cases and the
way the reverse idler shaft is mounted to the case.

The 2.9 trans will also likely NOT have most of the various upgrades.
to the 3rd gear synchro and to the 5th-reverse assembly or the taller '94 shift tower.

I'd honestly recommend looking for a '93-up 2.3 or 3.0 4x4 trans
and swap the entire set of internal parts into a 4.0 case.
But that's me, I like to go for the ideal.

AD

 

[OldRedB2_84]

try reading this thread from the beginning,you woulden't need to ask

thanx dude, i did that already!

allanD, thank you, i think i'll look around for one of those m5od's

 

[bigpotato555]

hey AllanD got an other question for you....on a scale to 1 to 10....what will be a 4.0l swap vs a fuel injected 302? for the skill needing and complexity and the cost....would it be worth swaping for 4.0l if i would be swaping for a 302 in 3-4 years? thx again your the best!