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injected v.s. carburated


Put a 4.0 in it.

The 2.9 was pretty well maxed stock. It can be blown, but that gets dicey with the head-cracking issue. Your engine should have the re-designed heads but I still wouldn't want more than 2 or 3 pounds boost.

The 4.0 is everything the 2.9 wasn't and then some. Best part is that is bolts right in place. It's stroked, bored, better cams, etc. You can't do any better than that if you want to get more out of a 2.9.

Putting a carb on a 2.9 while possible with enough effort, you won't make any more power with a carb. FI systems are designed to make optimum power, economy and emissions. With a carb you will get one of those at a time if you are lucky.

The final thing is, for any power gains you get by modding a 2.9, you will get the same power or more out of a 4.0 swap for a lot less.
 
And no matter what, carbureting the 2.9 is certainly not the way to go.
 
4.0 dude. Its awesome. it makes a B2 everything it should have been.
 
+1 to the 4.0 suggestion.

:icon_thumby:
 
Years ago I had discussed with a 2.9L engine nut about squeezing more power out of one. Yes, it is possible to get a bit more performance out of one, but unless you are either really bored or for some strange reason overly attached to the 2.9, you're far better off with a bigger motor.

Since you have a 1990, the swap to an EFI 4.0L is easy, there is very little that needs to be changed usually. An EFI 4.0L swap in an older BII (like my 88) is a real headache unless you are willing to swap the dash out.

To get the most out of a 2.9L motor, it requires a rebuild and aftermarket heads that are not prone to cracking or warping. Then add a Scorpio intake (twin throttle body) and a MAF instead of the cranky speed density system that the 2.9L floundered with. With the conversion to MAF, you have to change the wiring harness and computer. And since there was no computer designed to run a 2.9L with a Mass Air Flow sensor system, it may be dicey to try to get it to run right.

Some day when I'm rich and bored I might give a go at making it work just for ships and giggles.
 
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Didn't 88 and later 2.9l's have the MAF system?
I have an 88 and had two 89 BIIs with the 2.9, all three had the speed density system. MAF only came about at the tail end of things when they changed to the 3.0L and 4.0L 6-cyl motors.
 
I think all the later 2.9l's I've come across had the MAF sensor. So I had just assumed when the EGR vlave and larger throttle body were no longer used for 88 and later that, that was because of the new MAF system.
 

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