2.2L VS. 2.5L Please! Help Me Decide On My Rebuild

[Subliminal]

I'd suggest a 2.5L, but for a different reason: They're a dime a dozen. You can go to the JY and pick up anything you need...wiring harness, smec, blocks, etc...

They seem to be MUCH easier to find. And at boost levels which the computer can still control, with a nice intercooler, you'll be able to run either one for a long time...

Try finding a smec for a 2.2 L, then try finding one for a 2.5....

d

[The Barron]

SMEC for a 2.5L T1 auto? ... sure.. how many do you want?! haha!

[CaptTurbo]

It really depends on what you need the car to do. Going to the track on a regular basis... get a 2.2. Granted that everything is fairly equal, a 2.2 will always have more top end than a 2.5. Once you give that first shift at the track, you're gonna hit every gear at a higher RPM and miss some of the power band of the 2.5. Now a 2.5 without balance shafts will help...upping your RPMs a bit and putting a big turbo that will push alot of air at high RPM without protest will help alot more... let's not forget what Mr. Donovan has done with a 8V 2.5L at the track.... But all things being equal the 2.2 will always be more of a top end car....
Now if you're on the street most of the time, nothing goes from sitting on some joker's bumper to going around him instantly like a 2.5... you just can't beat the instant torque... the power does go away on the top end, but by the time that has happened, you're well past the car you needed to pass, and on the street you can shift a little lower in the rpm and keep in the mid range of the car and be quite quick around town, and have alot of fun...especially coming out of turns, by the time you leave the apex, you're at full boost and flying again. As daily drivers, 2.5's are alot of fun, and if you want to make strip power and performance, it can still be done... and when some guy pulls up beside you on the boulevard doing the limit, and you're cruising in 4th gear, and the guy decides to punch it without any warning so his girlfriend will think he has a fast car after he takes a big jump on you when you don't even know you're racing... you're gonna like those 400ft lbs that I heard are somehow useless. It might be tough at the track controlling that power, but once rolling in a higher gear, that 400lbs is going to pull you out of that gear and past the other guy so fast, he'll have to fake a heart attack so that he can still be cool around his girlfriend. When I punch the gas, I want the car to jump out of it's clothes and take off, a 2.5L will do that, take off right away with lots of torque pulling you... if you're constantly driving at 5000 rpm, get a 2.2, if most of you're driving takes place lower in the rpm scale then a 2.5 is you're best bet...Is it better to make torque higher in the rpm...if you want to make more power it is, but then again, are you at high rpm right now... if not, then that torque will do nothing for you and you're car will be a dog everywhere but the track...if you make the torque in the most usuable range, where you spend most of your time driving, you will be happier... if you're always at lower rpm around town, well then you want your power on the bottom end where you can actually use it... but then your car might end of being a dog everywhere but in traffic and light to light sprints...You have to know what you need the car for to know where you want your power to be... you can make all the power you want at 6000rpm, if you never bring the car past 4500, what was the point, you've made your car essentially slower. Either engine can be made to perform both on the street and strip, you just have to take slightly different approaches... so the question is, what do you want? Low speed passing power, do you want to own the highway, do you want to win at the track, do you want your power spread out over the power band or everything at once...Once you know where you want your power, you can make your choice based on that.... and the 2.5L internals aren't made out of pistachio shells, they are plenty strong and can take plenty of abuse...if you want to run tons of boost on a stock engine with a stock head gasket and crappy gas, don't blame it on the piston after. A 2.5L has most of the things that a T2 car has, and the internals are pretty much as strong, just no floating pins, etc, it got the same heavy duty 555 trans, etc,... let's not forget that a 2.5L makes more torque, and with all around bigger displacement and a bigger fuel curve, it puts alot of punishment on the engine and the engine was build for this punishment. It has the same injectors as a T2, and it runs less boost and isn't intercooled, that's why with a 2.2 computer, you need +20s just to get back to par (with a little to spare). A 2.5L engine is beefed up in it's own way, and is a stout piece, and odds are, whatever you did to kill the pistons in a 2.5, you probably would have killed them in the 2.2 as well... a t2 is a bit stronger, but not much

[beefalobilly]

Quote:

Hopefully I didn't come off too harsh. Sorry if I did.

haha, don't worry about it

[CaptTurbo]

sorry guys I didn't realize my post was so long until it was posted.. I just started typing and got carried away.

[moparzrule]

Well since you wrote a book it's really hard to reply without writing another from the SOOOO many things you are wrong about. I'll just name a few.
You said 400 ft/lb, I don't think so on pump gas. There have been some people than have dyno's of 400 ft/lbs in an automatic, but an automatic has torque multiplication so it actually ''tricks'' the dyno into thinking your car is making more torque, it isn't. Swap in a 5 speed and you will find out real quick you have 50-100 less ft/lbs than you thought.
A 2.5 has the same rods as a 2.2, therefore has floating pins. It's a good thing, but I'm just pointing out something you were wrong about...
A 555 was NEVER behind a 2.5 from the factory.
2.5L pistons are well known to be much more fragile than 2.2 pistons, therefore internals not as strong. 2.5 has cast crank as well, 2.2 has forged. Although it's not usually a problem area, just thought I'd point out a stronger component of the 2.2.
I am not positive, but I believe Gary Donovans relentless was a 2.2 not a 2.5.
All TD's are naturally torqey, my 2.2 gets around town just fine and it's acceleration at 1000 RPM really surprises me. The simple point is this, everthing being equal, a 2.2 car will win in a street race light to light. While you are there spinning your tires from all the torque you seem to like I will be gone already. A 2.2 will also win in a highway race, sure you might get 2 car lenths from the extra torque, but once you top out at a little over 100 I will be passing you.

[moparzrule]

I'll also say this, 2.2's get better gas mileage. With todays prices, who wants to have a fuel hog? I bet the difference is 4-5 MPG, do the math. If you drive 10000 miles a year, the difference is $200. Hmmm

[86Shelby]

Quote:

Originally Posted by moparzrule A 555 was NEVER behind a 2.5 from the factory.

1989 Turbo Caravan. That's where I got my transmission from.
The A-568 was in the '90 turbo Caravan.

[moparzrule]

Quote:

Originally Posted by 86Shelby 1989 Turbo Caravan. That's where I got my transmission from. The A-568 was in the '90 turbo Caravan.

Whoops, my bad. Forgot about that one, but that is also insanely rare.

[The Barron]

Quote:

Originally Posted by moparzrule I'll also say this, 2.2's get better gas mileage. With todays prices, who wants to have a fuel hog? I bet the difference is 4-5 MPG, do the math. If you drive 10000 miles a year, the difference is $200. Hmmm

Regarding MY paticular case..


Daily driver = Suzuki swift. 44mpg. Wheee! got 5 bucks?! We'll drive for hours!

[86Shelby]

Here's the dyno plot of my 2.5 TII that I mentioned. Thanks to Joe, others get to marvel at it's mediocrity.

[Mopar_Nutz]

Based on everything in here it seems like the way it works for a daily driver is....

2.5 is nice with a few mods, but close to stock. But if you mod it heavily it'll get to be a bit troublesome due to too much torque and a weaker piston design and then the 2.2 would be a better choice.

So I'd say it depends on how far you're going with the car. For heavy mods you can get all the torque you need plus more top end from a 2.2. If you're keeping it mild, the 2.5 is more responsive at lower boost levels.



BTW I voted 2.2

[The Barron]

Quote:

Originally Posted by Mopar_Nutz 2.5 is nice with a few mods, but close to stock. But if you mod it heavily it'll get to be a bit troublesome due to too much torque and a weaker piston design and then the 2.2 would be a better choice.

12-14psi is pretty mild around here...

[glhsken]

Nutz and C'Turbo.. You are both wrong on some facts.

BTW, Nutz Relentless was a 2.2 then went 2.5. Who knows what we'll see out of it when it pops up again.

C'Turbo, My little old 2.2 has no issues WELL below5000k rpm. '86's "S" made 80 ft lb more tq than hp. Mine made 50ft lb more tq than whp (with 45% more hp than his plot) Now, how large was that difference in Tq again????

The starter of the thread got his info and asked that I lock it down before folks got to arguing. Good stuff for the most part. (Man, how many of these 2.2 v/s 2.5L threads have we had??.

As long as good info comes out, we'll keep it open. crap starts, those posts will be deleted and the thread locked.

[turbovanman]

Quote:

Originally Posted by glhsken Demps, They MAY be capable of taking 300whp ( and Yes paul smith did run them, he popped them pretty often... ) BUT, you better have it tuned perfectly, A hiccup and the 2.5's will turn on you. The 2.2's are MUCH more forgiving.

Yep, I'll vouch for that.

Even though the OEM ones are taking quite the beating over aftermarket, guess with them being so old, there wear hardened, lol!

MoparNutz, theres no such thing as too much torque.