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josh-the-ranger
08-29-2007, 10:53 PM
i have the 2.8 in my ranger 4wd. it seems pretty weak, im lucky if i can hit 60 on the highway. would pulling the emmisions and new exhaust help significantly?

baddis
08-29-2007, 11:38 PM
pulling the emissions is against federal law. you might start with a good tune up. and also you didn't state the gear ratio or tire size that could also limit power.

Stumpy
08-29-2007, 11:59 PM
Gear ratio vs. tire size is very important.

Increasing (numerically) the ratio of your gears will have a huge effect over minor engine modifications.

josh-the-ranger
08-30-2007, 12:10 AM
i wont pull emmisions just put a manual carb on, i heard a 2 barrel off a 360 works? my tires are 31x10.50 bfg all terrains. stock gearing as far as i know, i dont know how to check the gear ratio..

how much would it cost to gear it down a little?

btw its a 5 speed manual

baddis
08-30-2007, 12:17 AM
i would look in the local yards to find the gears already set up to minimize cost i am running 31x10.50 and 4.10 gears and have no lack of power with an auto.

Stumpy
08-30-2007, 12:18 AM
There should be a tag on the differential cover on the rear axle that will have the ratio on it, or you can look on the inside of the drivers side door for the axle code.

Use this for reference...
http://www.therangerstation.com/tech_library/Axles.html


Stock can range anywhere from 3.08 to 4.10, it's helpful if we know what ratio you have, especially for 31x10.5's.
I have 3.45 gearing with 31's and my 2.9 is a dog, if your tires are too big for your gearing the only other option would be to drop in another bigger motor (i.e. 5.0L), little performance mods won't make much difference.

fastpakr
08-30-2007, 08:26 AM
I would seriously consider a Duraspark conversion on this as well as a small Motorcraft 2150 carb. Try to keep at least the smog pump if possible.

85_Ranger4x4
08-30-2007, 09:29 AM
I would seriously consider a Duraspark conversion on this as well as a small Motorcraft 2150 carb. Try to keep at least the smog pump if possible.

+1

Just pulling the stock carb will mess with the stock ignition as well.

josh-the-ranger
08-30-2007, 10:10 AM
i just went and looked, i have 3 73 gears. should i get 4.10 gearing?

jeffcv33
09-29-2007, 03:35 PM
dude. 3.73 gearing should pull 31's easy. you might want to look elsewhere rather than gears

josh-the-ranger
09-29-2007, 07:34 PM
could this be part of the problem? http://img165.imageshack.us/img165/5671/img9912smallkh7.th.jpg (http://img165.imageshack.us/my.php?image=img9912smallkh7.jpg)

fastpakr
09-29-2007, 08:06 PM
Are you talking about the factory crimp in the manifold pipe?

josh-the-ranger
09-29-2007, 08:10 PM
yeah it looks kinda restricting

fastpakr
09-29-2007, 09:20 PM
Perhaps a little, but the engine runs just fine (even with that) as long as everything is performing as it was designed. Duraspark and non feedback carb along with a good tuneup should be your first stop. Once you're sure everything is up to factory standards and aren't satisfied, then it makes more sense to look at your remaining options.

Will
09-29-2007, 09:50 PM
Could start with a compression test and make sure the motor is sealing.

martin
09-30-2007, 02:30 AM
It sounds like the ignition is not advancing. try pulling codes to give you a starting point. I'm running 33's with 4:10 gears and it performs just fine. I am durasparked though but it performed reasonably well with the factory setup.

Forcus
10-03-2007, 08:10 AM
The emissions equipment in and of itself will not likely cause you to not be able to maintain 55. I'd first check to make sure your compression is up to specs. My truck runs decent but spews oil smoke out of the dipstick hole. Minimum spec is around 100 PSI, mine is 75-85 PSI. This is enough to cause low power, hard starting, etc.

If you are not using oil, and you have no obvious mechanical problems (also remember the valves are manually adjusted, and also a check of the timing chain, by using the distributor), I'd look to fuel and timing. This is where many people toss the emissions equipment and I can't blame them as the system is hard to diagnose and relatively complicated, and parts are not readily available (new). Not saying you can't make it work perfectly, but if its a driver you have very little time to diagnose.

Most people in this boat convert to a 70's electronic distributor and a same-era Duraspark box, as well as a Motorcraft non-feedback carburetor. Please note that you can take the feedback carb out of the loop and convert it to non-feedback or keep the EEC IV ignition and use a standard carb. This will eliminate some wiring and hoses.

Personally, the very best setup for a carb'd 2.8L would be a remanufactured (a GOOD one... not a junk piece) Motorcraft carb tuned with a wideband and using a modern high flow catalytic converter that does not require air injection. For ignition I would use a brand new Duraspark and new 2.8L aftermarket distributor, and possibly replace the Duraspark with an MSD / Crane / Mallory ignition box.

85_Ranger4x4
10-03-2007, 08:44 AM
If you are not using oil, and you have no obvious mechanical problems (also remember the valves are manually adjusted, and also a check of the timing chain, by using the distributor), I'd look to fuel and timing.

The 2.8 has timing gears, no chain involved.

Forcus
10-03-2007, 11:44 AM
The 2.8 has timing gears, no chain involved.

My fault, and thanks for the correction!

josh-the-ranger
10-04-2007, 09:50 AM
Hi all thanks for all the helpful comments.

I changed my exhaust to a cherry bomb and rebuilt the carburetor put an new oversized air filter(other one plugged solid), new plugs, runs awesome. one problem though the electronic choke doent work so i turned it all the way back, so i have no choke.Now in the colder weather it likes to stutter in lower rpms, i have a manual carb im gonna be putting on for this winter. Another thing i noticed is that in third gear i can go up to 70mph, why in the world did they put a five speed in my truck when i dont even need fifth? i always cruise at 55, 60 in fourth gear and im getting 18.5 mpg on 31's.

85_Ranger4x4
10-04-2007, 10:05 AM
Because the truck came with tiny tires stock, like 205's or 215's, it should say on the sticker on the drivers side door what it came with originally. My 235's are even oversized, but filled the wheelwells nicely before I lifted it.

josh-the-ranger
10-04-2007, 11:55 AM
Oh i see, thanks for clearing that up.

Forcus
10-05-2007, 10:50 AM
For the gearing your truck had, and the tire size stock, and the power range, the factory trans was probably the most efficient setup.

With your bigger tires and low power (age, wear, etc), 4th gear is evidentally what works the best. The bigger tires serve to lower the RPM for a given speed, which can take you out of your power range. A gear swap would likely bring you back to having a usable 5th gear, but, it sounds like you have other engine issues to work out right now.

I'd advise either getting a new Weber carb conversion kit (~$450 from an online supplier) or an Offenhauser intake and a Holley or Edelbrock carb. From what I've read, the Weber is a bit more tractable in daily driving. But if you have other issues, or the wrong gearing for your setup, you may not see any advantage.