T2 2.2 to 2.5 conversion how much HP gain?

[DakotaKid]

The tires spin all the time.
It is weak on the top end, Turbo is too small.

[oldgregg]

Here's a comparison, not HP related for you all.
My pal has a similarly modded 2.2 to my 2.5, both in G bodies.

We ran the same amount of boost, got the same ET's, (within 100ths') but he hit just over the 100 MPH mark while I hit the 96 MPH mark & I've never attained 100 MPH through the traps yet.

[ToiboTonaZee]

Id have to say for the street and a 5spd the 2.2 would be a funner car to drive.
The 2.5 has plenty of torque but just runs out of breath in the higher RPM. If you put a bigger turbo on it this would slightly uncork it and you could put the power to the ground a little better.

my opinion: For a friday night cruiser id take the 2.2 because you can put the power to the ground a little easier and wind it right out.
A 2.5 on street tires would almost be scary unless you had a bit of lag...

[macncheese]

scary for some is fun for me!!!!!
tony

[Ben Paquin]

Quote:

Originally posted by ampsyco can i ask you guys how that feels?? 300 ft lbs of torque ??? . but i want to know if its weak at higher speeds.

Feels like you've been rear ended lol.

Ever since I have gone from 2.2 high boost to 2.5 high boost. I don't want to go back. Even if the 2.5 is more "fragile" piston wise. The 2.5 is extremely powerful even at high speed. I raced my 3140 lbs Lancer 2.2 Super60 at 25 psi and the 2900 lbs Daytona with a stock TII turbo at 21 psi and both were neck and neck till 125 mph when we usually shut off. Gives you an idea....

2.5 makes similar HP at the same boost level but more torque. Dont' worry it's plenty fast on the highway. A couple of LS1 owners know that...

[Ben Paquin]

Quote:

my opinion: For a friday night cruiser id take the 2.2 because you can put the power to the ground a little easier and wind it right out. A 2.5 on street tires would almost be scary unless you had a bit of lag... [/b]

That's not true. I found the 2.5 actually easier to launch because it has enough torque to recuperate from a bad launch. Meaning it won't bog as much as a 2.2 if you grip too much on the starting line. Also spool up is a bit better which is great from races from a roll...

You guys got to learn how to modulate the go pedal and feather the clutch...

[Brian Putman]

Quote:

Originally posted by ToiboTonaZee Id have to say for the street and a 5spd the 2.2 would be a funner car to drive. The 2.5 has plenty of torque but just runs out of breath in the higher RPM. If you put a bigger turbo on it this would slightly uncork it and you could put the power to the ground a little better. my opinion: For a friday night cruiser id take the 2.2 because you can put the power to the ground a little easier and wind it right out. A 2.5 on street tires would almost be scary unless you had a bit of lag...

Something that needs to be considered between a 2.2 and 2.5 is the longer stroke tames an already tame stock camshaft even more! A longer stroke engine needs a longer duration cam to get the same rpm potential as a shorter stroke engine with the same displacement. But the longer stroke engine will not loose as much bottom end torque (if any up to a point) as the shorter stroke engine when a larger cam is used.

[glhsken]

Quote:

Originally posted by Ben Paquin F 2.5 makes similar HP at the same boost level but more torque. Dont' worry it's plenty fast on the highway. A couple of LS1 owners know that...

No where near similar, unles you call 20-25% less similar. Torque is typically 15-20 percent above a 2.2 but drops off a cliff above 4k rpm.

[Ben Paquin]

Quote:

Originally posted by glhsken No where near similar, unles you call 20-25% less similar. Torque is typically 15-20 percent above a 2.2 but drops off a cliff above 4k rpm.

20% less ?

stock TBI 2.5 = 100 HP 135 ft-lbs
Stock TBI 2.2 = 92-96 HP (depending on year) and 121 some ft-lbs

Apply boost and if the turbocharger and the rest of the setup is the same on both, HP/torque proportions between the 2.2 and 2.5 should stay similar.

I owned both 2.2 and 2.5 in TBI versions and turbo I and II versions. I had a Shadow with a 2.2 TBI and one with 2.5 TBI. Similar equipement both autos. The 2.5 was definately quicker, not only on takeoff. The situation was the same with turboed 2.2s and 2.5s.

[turbovanman]

All I know is my 2.5 makes lots of torque. I love the feeling you get when you launch, the exhaust makes a wicked wail and it pins you back in the seat, woo hoo.
As for rpm, I have to agree, after about 5000RPM, your just spinning, no power but until I rebuild my trans, I have to put up with shifting at 6200 RPM

[Shelby VNT]

You can't really compare numbers from NA 2.2 and 2.5 engines and then expect with the addition of a turbocharger that they will both increase their output in a linear fashion. Also, it doesn't do either engine justice when you can't look at the dyno charts and study the curve of the powerband.

Comparing turbo engines to turbo engines, the way each engine makes power is different. On the upper end, higher in the revs, the 2.2 Turbo II will start to walk away because it makes more horsepower. It's torque that gets you off the line, but the horsepower that gives you your top end pull.

Both engines are good. Both can make gobs of torque, depending how you tune them. It's true the 2.5 Turbo I can make torque more easily, but don't let that fool you. We've all seen dyno charts of the 2.2 Turbo engines making darn near 400 ft/lbs. Alot has to do with the set-up and the tuning.

There are so many different variables in cars, drivers, parts, tires, and launching techniques that I don't think even cars with similar set-ups could reasonably compare on the 1/4 mile. Now, lets say from a roll on the highway, starting from about 40 mph, things might be different and then you'll see what everybody is saying when they mention the 2.2 making more horsepower.

[Ben Paquin]

Quote:

Originally posted by Shelby VNT You can't really compare numbers from NA 2.2 and 2.5 engines and then expect with the addition of a turbocharger that they will both increase their output in a linear fashion.

Compared to each other I said. Of course if you raise the boost the exhaust becomes a bigger restriction causing a bigger rise of torque than HP in both engines. Unless changes are made on the exhaust side. But compared to each other the 2.5 should not make less HP with the same boost as a 2.2. I have owned all of them and tuned friend's cars with both. The 2.5 is quicker both on the highway and takeoff at the same boost level.

Quote:

On the upper end, higher in the revs, the 2.2 Turbo II will start to walk away because it makes more horsepower. It's torque that gets you off the line, but the horsepower that gives you your top end pull.

Man, just take out the wheezer Mitsubishi turbo and put a Garrett on the 2.5 (like I did) and you'll see if a 2.5 can't move on the highway.

Quote:

Now, lets say from a roll on the highway, starting from about 40 mph, things might be different and then you'll see what everybody is saying when they mention the 2.2 making more horsepower.

Have you read what I typed ? I have raced my 2.5 with less mods vs my 2.2 with more boost and the 2.5 stayed side by side all the way to 125 mph ?

Isn't 108.4 mph on the 1/4 mile with 18 psi of boost with a 2940lbs race weight enough top end ? That's a stock 2.5 with a Garrett T2 and 2.5" dump.

[glhsken]

No, You don't listen to what anyone else types. I've been heavily involved with both 2.5 and 2.2 build-ups. Bringing NA's into the loop is a waste of time.

Quote:

But compared to each other the 2.5 should not make less HP with the same boost as a 2.2.

Dyno plots don't lie... The 2.5 falls flat and the 2.2, while falling flat doesn't quite jump off the same cliff.

[spoolboy]

I keep trying to tell these Ford guys that the 302 is better than the 351, the chevy guys that the 305 is the better engine, and people just don't listen when I tell them the 273 is the best small block. Wonder why?

Most of the guys that are hung up on 2.2s have invested too much time and money in them to even consider that a 2.5 might be better, or even just as good. If there's one thing I've learned from messing with cars, it's that once someone has spent a lot of money on something, it's great. For these guys price = quality. Most of the guys that are hung up on the 2.2 have not driven/ridden in a well built 2.5.

I've convinced a couple of people. My 2.5 @ 7psi would walk a 2.2 @ 11psi on the highway. Of course there are many good reasons why, but I won't bother to muddle this argument with facts.

Dennis

[spoolboy]

Quote:

Originally posted by glhsken No, You don't listen to what anyone else types. I've been heavily involved with both 2.5 and 2.2 build-ups. Bringing NA's into the loop is a waste of time. Dyno plots don't lie... The 2.5 falls flat and the 2.2, while falling flat doesn't quite jump off the same cliff.

A 2.5 at 4840rpm moves the same amount of air as a 2.2 @ 5500rpm. A 2.5 at 2500rpm is the same as a 2.2 @ 2840rpm.

Take a 2.2 dyno, and a 2.5 dyno. Adjust 2.5 dyno with a graphics program so that when you overlay the graphs, the 4840rpm and 5500rpm line up and 2500 and 2840 line up.

See what it looks like then.

The power drops off due to restriction. Unrestrict it and things change drastically. You gotta find the restriction. Camshaft is a good place where most don't look. With camshaft needs to come compression.