2.2 or 2.5 TIII?

[turbovanman²]

I have pretty well sourced up all the parts to get my R/T running again so now the final question is, 2.2 or 2.5? I know my van is a 2.5 TIII but its not really a fair comparison I believe.

The use, 99% daily driver, family hauler with some drag strip duty on street tires or drag radials. I will probably split commuting with it and my van next summer and when I am not using it, the wife will be, :eyebrows:

Having said that, I've drove it when the previous owner had it and it was fun but never got alot of seat time.

So anyone with a 2.5 TIII R/T, would love some feedback and or yays and nays. I don't plan on going nuts with this, mild port, exhaust, big FMIC, stockish cal and maybe a 50 trim T3/T4 or I'll just throw on a 60 trim Tbird turbo.

Thanks guys.

[ShelGame]

I don't have a 2.5 R/T. My Spirit R/T is a 2.2. But, I think the car really has no balls off the line. It needs to rev to get going. I have a couple of 2.5 tall decks and a Lotus head just waiting for me to get the money to built it for something...

[turbovanman²]

I don't have a 2.5 R/T. My Spirit R/T is a 2.2. But, I think the car really has no balls off the line. It needs to rev to get going. I have a couple of 2.5 tall decks and a Lotus head just waiting for me to get the money to built it for something...

What turbo?

Tall deck, something else to consider, :eyebrows: :confused:

[JuXsA]

2.5 torque baby!!!

[Turbo3Iroc]

My Spirit is my daily driver and it has the most low end of any stock T3 car I have driven. Put a 3" exhaust on it and it's still there. My vote is 2.2.

[ShelGame]

What turbo?

Tall deck, something else to consider, :eyebrows: :confused:

Stock.

[GLHNSLHT2]

Simon since you have both you should be able to choose. I'd stick with the rule of thumb, heavy car=2.5 light car 2.2. My Daytona will someday become a 2.5 16v.

[turbovanman²]

Simon since you have both you should be able to choose. I'd stick with the rule of thumb, heavy car=2.5 light car 2.2. My Daytona will someday become a 2.5 16v.

Not really, the R/T is headless and not driveable, :o

[bakes]

16v 2.5 tall deck FTW

[iTurbo]

I have a nice built 2.5L TIII ready to go for my Lancer. Haven't put it together yet since the project snowballed something serious. I decided to do 2.5L because I've always been really unhappy with the low end torque with the 2.2L in my Spirit R/T. Like Rob says, it really does need revs to get moving. I went with a 3.50 gear on that car so that didn't help things either although it's great on the highway.

I vote 2.5L.....just check out Cliff's old wagon..

[Aries_Turbo]

yeah but cliff said his wagon was undrivable with the 2.5L torque till he swapped to a .82 a/r exhaust housing for more lag and less low end grunt.

that makes me vote 2.2

Brian

[GLHNSLHT2]

So bolt on a .82 housing :)

[johnl]

Tell me if I am wrong but the idea behind a tall deck is to allow the use of a longer rod and that in turn will alleviate the rod angle problem of the 2.5 and so allow the 2.5 to rev a bit higher. Right? You also have room for a bit longer skirt on the pistons too - less "tuna can" ish, better ability to hold the rings square to the cylinder wall.

You will still have a piston speed issue though. And, the 16v head will allow you to pump the additional 300 cc to a higher crank speed than could be acheived with an 8v.

So, assuming you are not particularly worried about engine longevity/high piston speeds - go with the 2.5.

[GLHNSLHT2]

Good thing about a 2.5 is you don't have to rev it unless you want to :) Stump pulling torque and with a good flowing 8 or 16v head can have good/great top end too.

[Turbo3Iroc]

yeah but cliff said his wagon was undrivable with the 2.5L torque till he swapped to a .82 a/r exhaust housing for more lag and less low end grunt.

that makes me vote 2.2

Brian

His old wagon is now a 2.2 and has been since soon after it was sold.

[iTurbo]

How could you pair a tall deck block to a TIII head anyhow? I don't see the TIII-specific crank sprocket bolting onto the crank since it's not a common block.

[JuXsA]

http://www.juxsa.com/carstuff/carstuff.htm

if dodge had built!!!!

[bakes]

Simon has already made a crank snout adapter for his current TIII 2.5 motor (van motor)
Or use a C/B crank and front seal cover plate

[iTurbo]

Simon has already made a crank snout adapter for his current TIII 2.5 motor (van motor)
Or use a C/B crank and front seal cover plate

Ahh, I did not think that was possible. I thought Simon was using a regular 2.5L CB crank and block? So are you saying you can use a CB crank in an early block by only changing the front seal housing? Or does this only apply to tall blocks?

[cordes]

I love the gas mileage that my 2.5 provides in my shadow. I have a bit of tuning to do in my omni before I declare the 2.5 the gas mileage winner, but I am leaning that way right now. I say 2.5.

[rx2mazda]

Lotus head was designed to rev, 2.2 FTW!!

[turbovanman²]

How could you pair a tall deck block to a TIII head anyhow? I don't see the TIII-specific crank sprocket bolting onto the crank since it's not a common block.

I am running a 2.5 tall deck crank in my CB due to an error on my part, I got given a fresh, reground crank and didn't look at the pulley snout close enough as I was concerned with the sealing area size, which is the same as a CB. I put it all together then went to put the TIII crank pulley on and the hole was too big. A machinist friend made me a shim to fit the TIII pulley onto the crank, phew.

I do have to admit, I love the midrange with the 2.5 and if I need to rev it, hold on, :partywoot:

I just advanced my intake cam 4 deg to match the exhaust and turbo lag all but disapeared, when I hammer the gas off the line now, it spools NOW, and boost builds instantly and hard, :clap:

So looks like I need to buy some pistons next spring, thanks guys, :nod:


Jeremy, check out my thread, I just added something to intrique a few people!

http://www.turbo-mopar.com/forums/showthread.php?t=29445