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

[86Shelby]

Quote:

Originally Posted by The Barron 2.5L T1@7psi= 150@4800 | 180@2800 This makes me wonder.. what kind of HP/torque #'s does a 2.5L give up when fed 14psi of intercooled charge?

With tuning and 16psi I ended up with 200-201 HP @4100-4400 RPM and 288 Ft/Lbs @3300 RPM at the wheels. Granted, there was no torque multiplication from the converter since my 2.5TII is backed by an A-555. I've seen a couple 2.5 dyno graphs that have HUGE(450+Ft/Lbs) torque numbers due to the flash stall of the converter.

I say go with a 2.5. You have all the criteria to fit a 2.5 the best. Heavy, automatic equipped car, daily driver capable. All signs point to a 2.5L. I fit the 2.2L category best, light, stick-shift car.

If someone will tell me how to get a screen shot I'll upload a pic of that dyno graph for you if you want.

[2.2TurboJoe]

Quote:

Originally Posted by 86Shelby If someone will tell me how to get a screen shot I'll upload a pic of that dyno graph for you if you want.

1) do a print screen with the button on keyboard (shift + print screen) from
the run viewer
2) open Photoshop and click FILE, then NEW, then click OK
3) then just hit CTRL and V and it will appear in the blank white space.
4) go to SAVE A COPY and choose jpg version

[beefalobilly]

Quote:

>I CANT REALLY AFFORD FORGED PISTONS<

I could be wrong but wouldn't this be a reason to get the 2.2 since the 2.5 has weak pistons? I don't really know when they start to break

[The Barron]

Quote:

Originally Posted by beefalobilly I could be wrong but wouldn't this be a reason to get the 2.2 since the 2.5 has weak pistons? I don't really know when they start to break

This is something I thought over too. But at 14psi and keeping a good A/F ratio..whats the risks then?

[TurboMinivan]

Quote:

Originally Posted by beefalobilly I could be wrong but wouldn't this be a reason to get the 2.2 since the 2.5 has weak pistons?

Say what?!? Weak pistons? Give me a break. The factory stock slugs are stout enough to push a big fat minivan into the 12s on 28-odd pounds of boost... and this with 140,000+ miles on them. (See Paul Smith for reference.) I don't get how this can be perceived as weak.

Don't sweat it. In your nearly-stock 16 psi setup, they'll last forever. Hence my comment stating the same.

[TurboMinivan]

And here's another misrepresentation which ought to be addressed:

Quote:

Originally Posted by moparzrule OK but when your car tops out at a little over 100 don't come cryin to me

Let's not forget the criteria, folks. He'll be running an automatic, not a manual... and the slushbox gearing will be the determining factor of top speed, not the peak horsepower. Whether your displacement is 2.2L, 2.5L or 12.8L, 6000 RPM in third is 6000 RPM in third. At that point, stick a fork in it--you're done.

Quote:

And below 40 MPH you are only going to have traction problems on street tires.

It's called a two-stage boost controller. Look it up. (But then again, there are times when hazing the hides makes a bigger impression than a quick getaway. This added flexibility gives another advantage to the 2.5L.)

[The Barron]

Thank you all for your thoughts and input. I havent only been helped in making up my mind but have learnt some things too.

2.5L TII w/o Counter ballance shafts it is!!

Thank you all!


2.5L Turbo II ........ COMING SOON

[beefalobilly]

Quote:

Say what?!? Weak pistons? Give me a break. The factory stock slugs are stout enough to push a big fat minivan into the 12s on 28-odd pounds of boost... and this with 140,000+ miles on them. (See Paul Smith for reference.) I don't get how this can be perceived as weak.

Like I said i coudl be wrong, especially considering i've never owned a 2.5...i based my statement on this recent thread...2.5 strength?
and it seems like i read it elsewhere but i own a 2.2 and definately no expert

[TurboMinivan]

Quote:

Originally Posted by beefalobilly i based my statement on this recent thread...2.5 strength?

Oh, okay. Ken is right: the stock cast pistons are the weakest link in the engine... but only in the "least stout part present" sort of way. They're still plenty good for over 300 ponies to the pavement.

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

[SuperSleeper]

Quote:

Originally Posted by TurboMinivan And here's another misrepresentation which ought to be addressed: Let's not forget the criteria, folks. He'll be running an automatic, not a manual... and the slushbox gearing will be the determining factor of top speed, not the peak horsepower. Whether your displacement is 2.2L, 2.5L or 12.8L, 6000 RPM in third is 6000 RPM in third. At that point, stick a fork in it--you're done.

A very good point that I've never considered before. Dempsey, do you, or anyone, have any personal experiences to guess at what speed that is?

[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.

[Pat]

Looks like I'm coming in after the fact, but...

I definitely vote 2.2. I think it's hard to beat them. The power curve is a bit nicer than the 2.5, it's not as violent down low, you don't need to have a dual stage boost controller to control wheelspin and they certainly can make plenty of torque to burn the tires if you want to or to pull a heavy car. Plus, stock for stock, a 2.2 is a bit more durable than a 2.5 since the pistons are able to take more abuse.

Sure, a 2.5 will make more torque, but how much torque do you really need in a FWD street car? 400 ft lbs won't mean a thing if you cant get your street tires to hook up. A nice, steady 300 ft lbs or so is just about perfect, even with a heavy automatic. Plus, you get to keep the power higher into the rpm range.

My Spirit ES is a low compression, 2.2 automatic in a loaded car...power windows, locks, power seat, etc (it's heavy!) with a stock rebuilt A413. The only change to the tranny I made was increasing the line pressure a bit to bring the shift points up. I wanted it to shift at just below 6k to make use of the 2.2's power curve. The car is awesome on the street. Power comes on nice and smooth, it doesn't blow the tires away immediately (which I can do if I want to, but I don't have to fight wheelspin to get a decent launch on the street) and it pulls great. On 18 psi, it's done 13.53 @ 98.8 on pump gas and made enough torque to pull that boat through a 1.84 60 ft time.

Just another opinion.



EDIT: I should throw in that I'm using a custom cal with the correct spark curve for the G head on the car.

Pat Culkin
'91 Spirit R/T - 12.09 @ 115
'89 Spirit ES - 13.53 @ 98.8

[ray44420]

I voted for the 2.5 The long stroke helps produce torque, this is nice in a heavy street car. If you were building a drag car, the 2.2 would be a better choice. A street car spends time at all RPM levels, and the 2.5 "feels" great!

[STANNN]

the 2.5 feels better up to about 4,000. I'm running a 5spd now {with 2.2 I had a/t} and I like how it pulls at highway speed when I easy into throttle without down shifting. What I don't like is the way I seems to run out of steam so quickly, like I said, about 4,ooorpm. I'm using2.2 T2 ecu. with +20's.

[glhsken]

I did got he route Pat did with my Daytona. It's a "built" automatic in a 2.2L heavy T-top car. It's meant to be a street strip car. 2.2's put down plenty of torque, but it usually peaks around 38-4000rpm. The 2.5 will peak 33-3500 (typically)