Being as mine has 48k miles on it, there won't be a swap coming anytime soon. Fingers crossed.....
It's a beach buggy most of the time, less weight with the top off anyway. 😀 31's with a 2" lift going in right now. I hope it doesn't turn into a chore driving down the highway to the Cape this summer.
Negative Ghostrider. Unfortunately, the only thing that can be done to our TBI models is the Electric fan.
not true. I had a tbi chevy that I spent years tweaking and trying to squeeze the most out of it. You need to find a tbi unit that has the same bolt pattern, dollars to donuts there is one on a 4.0 jeep or an older 3.9/5.2L dodge truck that will fit. you may have to do some grinding on the intake so the inlet holes match. This is the one place where you want a TB spacer. the design will allow the atomized fuel to mix better with the air and deliver more fuel to the combustion chamber.
1995 YJ- daily driver
1987 Mustang- the money pit. " I wanna go fast!"
my build has really taken a back seat and production is slow. but I've gotten a lot of mileage out of this thread. thanks everyone for keeping it alive. my favorites so far have been the inertia ring from tri county gear Adding Flywheel Mass for Engine Torque | Tri County Gear and the e-fan. I'll be regearing one day I'm sure. 32's till then (yjmark ) but not till much later. See yinz in the spring.
Join the NRA ..
EXCITEMENT is BUILDING
Remember it's just a 4 banger what can you expect from it. I would never spend much money on it if it runs fine, re gear or go back to the smaller tires. You can't make it into something it's not. I have a 6 I know it will not amount to much unless I spend lots of cash on it. Again just re gear and it will be fine like the 4 banger a good engine that you can trust.
troof. I have noticed better acceleration with the injectors, tb, header, and e-fan but in all gods honesty gas mileage hasnt improved and its still not setting any speed records. good thing there is a 5.3 waiting in the wings.
1995 YJ- daily driver
1987 Mustang- the money pit. " I wanna go fast!"
FYI I just did a 4.0 TB on my 2.5 with a spacer. I have 4.11 gears and I noticed it's quicker. Hills are still a problem but it's better than it was. Have the inlet air done already. The E-fan is next then the headers and exhaust. I'm not looking for better gas mileage as if I wanted that I would be driving a small car. IF you are wondering I could do about 70MPH before the TB and spacer slowly but I could get it up there after the TB and spacer 75 MPH + with ease all in 5th gear. My tire size is a 32-11.5-15
Thanks to all for your investment in this thread. Were working with a 95 YJ 2.5 5 spd. Yes I know gearing is in mu future once we do 33's, but want the horses we can get for cheap. I've already done cat delete, fm super 44 muffler, Heading for electric fan, have a 4.0 throttle body to install, Possible timing adj. A couple questions for your intelligent chime in.... 1 Looks like ford Taurus is a simple fan swap? I can handle proper wiring ok Is that the best junkyard fan to look for? 2. Injector swap from junkyard, 4.0 litre? Mustang bosch yellow? Years? 3. Do I have to modify intake for the bigger throttle body? 4. Im considering slotting bellhousing to advance timing at crank sensor. Anyone gotten into that?? Side note, Had a 99 TJ 4.0 and put an air-raid spacer with the swirl interior and definitely helped midrange. That alone helped the 4.0
I can answer one of the questions. I just did the injector swap. Pretty much any year mustang with the 5.slow will have the correct injectors. Pretty easy swap, took me all of an hour.
I have a 9 with a 2.5. I am running 33x12.50 Super Swampers which are heavy as hell. With the 4.88 gears I can actually drive it like a normal vehicle, without having to run the rpms up to 4k.
I wouldn't waste money on anything other than gears. If that is not enough then do the other mods.
I have tried it on other Jeeps, and my motor is stock and I can easily pull away from my friends that have "modded" 4 bangers with 4.10's that aren't even TBI. They have newer YJ's and TJ's than mine.
The bast part is when something does go wrong, I don't have to remember what bastard parts I have put on it. This keeps things much more dependable and more common sense. The 4.88's put it very close to stock.
Put stock tires on you YJ and drive it around and feel the difference.
I see people do this all the time. Gears are no that bad to do, and not really expensive considering what you get out of it.
I get 18 mpg with mixed driving, and have gotten as much as 20. This is SOA +3".
wherever you go there you are..........
Hope I am on the right post about power on the 2.5L, I currently have had my 97 2.5L TJ and little by little on a tight budget I have gotten it pretty fast. I mean plenty of torque and that includes fast off the line and good top end even with head wind or going up hill. My current mods are a home built ram/ cold air intake. It consist a flat panel K&N filter, the front of the factory air box totally cut out, and the front right side of air box has a angle cut in it. The side cutout includes a aluminum angle plate that I can manually adjust the amount of air that comes in and the manner of force it comes in. I noticed its very sensitive. If I open it to much I lose torque. To little I lose top end power. So gotta find that sweet spot. Also at bottom of air box I have a hole in it just above the top of the shock mount. This air is good for instant take off response whille the front off open box is good for top end power. I also removed both headlight bezels and now I get cold air coming in around headlight just in front of air intake box. I also have a large intake tube wrapped with insulation without any bends in it. It leads to a 4.0L throttle body with a shaved shaft. Did have a 62mm on there once been it seemed like the lil 4 banger was not strong enough to suck in that much air. Next I have a GSP Power Spacer sitting under the throttle body which increases the air charge/velocity, works great. Also bored out the intake manifold from factory 48mm to a mild 55mm to macth spacer and throttle body. Still running factory exhaust manifold which I am happy with even after its been replaced twice through the years. I believe it keeps torque. Next follows a straight flow magnaflow muffler backed by the factory tail pipe. Again my belief in keeping torque. O I did cut the downward elbow at end of tail pipe and made it a little shorter and added a nice stainless tip that opens up to about 3 inch or so. Also instead of getting a electric fan I keeped the stock fan, I did not want to worry about additional motors or sensors going bad. Hey the fan stops spinning at certian speeds anyway right. To fire all things up I do have a optima battery with a CRT Performance coil which is rated at 45,000 volts. Accel is rated at 42,000 volts and MSD coil is rated at 38,000 volts if I remember correctly. I run accel 8mm wires and have had great experience with the NGK V groove plugs. My plugs are gapped at a mild .038. Again very sensitive, to big I lose torque and gain top end along with MPGs. To small of gap I lose MPG and top end power. So bottom line in my experience you have to tune your spark and air intake. How can one model cold air intake have optimum results for all jeeps. It all works together in sync. O yea I am a mild wheeler and only run 31s on 2inch lift with its 4.10 gears. She is a blast to drive and have all the passing power I need on highway. Happy with my lil 4 banger. Happy 4 Wheeling !!!
I plan on doing the majority of these mods just to squeeze everything out of the 2.5 I can. As it's been stated numerous times, the best thing you can do is re gear. I'm running 35's on my Dodge 4x4 & swapped out the 3:55's for 4:56's & it's like night & day. Worth every penny IMO. If I had it to do all over again, I would have went with 4:88's in the Dodge. I have 4:88's for the Jeep sitting on the bench out in the shop. They were my first purchase.
I'll do the 4.0TB, CAI, Efan, injectors & exhaust. I can find all of that locally for cheap less the header.
I like doing the poor mans mods. The best one I've ever done is the CPS mod for the 5.2/5.9 Magnum motors. It's basically a poor mans chip. Pull the CPS, notch out the mounting holes, re-install it & slide it all the way up against the bell housing to advance the timing. I might try it on the 4 banger to see what it does.
On my 2.5l 1991 YJ jeep, I've added a k&n air filter, spent 3 hours cleaning stock throttle body in kitchen sink and dawn soap, did away with cat converter as well last week, also added new plugs and spark plug wires, and took injectors from a police interceptor ford crown Vic and installed them in my jeep today, 19psi 4 hole yellow top black metal bottom. jeep ran good when I bought it 2 weeks ago, ran better after tune up and cleaning and cat removal last week, and runs even better after injectors installed, ive noticed it pull a steep hill today by my house in 3rd gear at 30 mph and continued to climb in speed, before it would bog down going up the same hill and I would either slow down or down shift to 2nd gear 2, injectors made that much a difference and tuneup, still looking for a 4.0 throttle body I want to see if it makes that much a difference.
Yes to that 4.0L throttle body, on mine it made a big difference, one of my favorite mods. I once tried a big 62mm and I lost torque, it was quick on the take off and to forever to reach higher speeds. My theory refers to air charge. Not only the amount of air coming in, I mean more air in is good but must retain air force or velocity. The amount of pressure that air is coming in. Its like a water hose that flows lots of water without a nozol. You add a nozel and you got water pressure. Ofcourse if you adjust the nozel to tight you lose the amount of water passing through. With no nozel no pressure. Did I just repeat myself. Anyway I read somewhere once that a stock 4.0L throttle body on a 2.5L is plenty good. It increases the amount of air coming in while still keeping a decent air charge. Yes the factory design on that got something right. The top side of TB is about 60mm and under the throttle plate is 55mm. That is the tapered V shape design that keeps the air charge. O on that other issue on CPS I have heard of that mod before, and yes you are right it would advance the timing. For me it sounds a little spooky even if it probably works. Also they have little gadgets that increase the voltage to your MAP sensor. I have heard good results on that. It supose to increase the injector pulse width at WOT, ( wide open throttle) giving you more power on high end. I yeah listen to this one, I forgot to mention what I did to my factory fan blades. Little by little I stared trimming the inside inner corners of the blades with a pair of snipes. In the end after trimming about 5 times my engine spools up alot quicker and seems to take off quicker off the line. My thought to that was less wieght or rotating mass. I also drilled two half inch holes in center of all blades. Got scared for a bit there. I thought I passed the point of no return. For a minute I thought it was not going to supply enough air to cool engine. But actually my engine cools better and less drag with spooling up alot faster and easier. Okay thats it for now gotta go. Take care guys and Happy 4 Wheeling.
Thanks for reply on the throttle body ill pick one up sometime soon, I also have a thick throttle body performance spacer under my stock throttle body that swirls the air so it should help the 4.0 throttle body as well.
Yea as far as throttle body spacers there has been a long debate whether they work or not. In my experience I say some do work depending on the design. We all know air has one similar characteristics as electricity. It likes to take the path of least resistance. Air coming through your intake down the intake tube and past the throttle body plate is not going to decide on its own two slow down and decide to spin in a opposite horizontal direction. The air will only ripple over any ridges. Any gains felt in power or torque come from increased air plenum. (The volume of air under the throttle plate) Now the one inch extension also plays a roll in the air charge ( velocity or pressure of air intake ). Also similar to intake runners on your intake manifold. As some people get new longer intake runners it increases torque, and torque equals horse power. So If you do use a throttle body spacer you would be better off using a straight through design for smoother air flow transitions. There is another which is the one I use. Its a gsp power spacer. Its has smooth air flow transitions and also increases air charge (velocity). Just saying how it works well for me thats all.
Our 92 2.5l Jeep will do 75 (if you like to shake and rattle) in 5th with 31 inch tires as long as you aren't going uphill, then you have 4th gear for that. We can also tow a 2500lb trailer down the highway at 60 mph in 4th. Not sure why you would re-gear unless you don't have a 5 speed. The tires only give you 10-15% difference in gearing (std tires are 27+ inches).
Yes I am sure that throttle body spacer you are running is doing something, I dont doubt that. Most TBS are rated at a 3 HP increase average and some really only deliver 1 HP. Its is possible to get about 7 to 8 HP out of a TBS with the right design along with existing mods. Like any other mod they perform at optimal levels when used in conjuction with other performance parts. Like Duh right. Or they are not working at full potential with a weak link such as worn out spark plugs or a dirty air filter. Just the other day I replaced my accel 8mm ignition wires with new ones and what a big difference. I thought ignition wires lasted a long time. Yes they might last long but what about the liftime of there performance. Many performance products advertise 10 HP or 12 increase and once installed it only really feels like 4 to 5. I rather have a product that says increase performance without promising any numbers. To me the best Dyno is what you can feel off the seat of your pants. Sometimes that can just be a complete tune up. Myself at this point I will probably keep my 31 BFG muds on my 2in lift along with its 4.10 gears. O yea I would like about a 3 to 4 inch lift and maybe some 33x10s. But then I will lose my existing power and will need new gears $$$, slip yoke eliminator , new rims or backspacing wheel spacers, along with added stress on all parts and every bolt. Hey if you can afford it and do it right, go for it. For now yes my rig has many mods under the hood. The exterior has many add ons and looks good. To me. She is realiable, light weight, fast in any RPM range, great off the line, good passing power and good top end speed. She is a daily driver and would only like to do mild wheeling . I dont wanna break anything. I am probably more into exploration or what they call over landing. O yea maybe later tonite I might try to regap my NGKs back down a tad to .037, I am getting a lil bucking on my first start up of the day. Sometimes I think its a sensor such as the MAP or IAC or maybe the distributor sensor, Huh ? Will see.
You can't get too crazy with the CPS or it'll ping. But you can't make it go that far without grinding the bell housing down & you can't do that without pulling the motor (at least on the Dodge Magnums). I'm not sure about the 2.5's. Haven't look at it yet.
On a side not, I pulled the 2.5 TB & installed a 4.0 TB tonight. All I can say is HOLY CRAP! I have been swapping TB's on motors for 10 years. Never have I EVER had a motor respond to a simple TB swap like this 2.5 did. Throttle response is dramatically improved & the engine pulls twice as hard as it did with the 2.5 TB. I'm getting the high idle on start up, but it comes down after 30 seconds or so. I can live with that. I highly recommend a 4.0 TB swap to any 2.5 owner.