2.5 block to a 2.2

[Jack's Dodge]

I want to change the charateristics of my 2.5 block, and make it a 2.2. From what I understand, the pistons are the main difference. Is there anything else. Wanted to get Mahles and new rings, and get moving.

[Alberta_Daytona]

I believe the whole point of the 2.2 is less stroke.... = diff crank....right???
I assume you will also have to change over some electronics...

I am wanting to change my 2.5 from a 91 shelby and swap it with a 2.2 from 89 shelby.

I could also use more info....mainly what electrical has to be switched over, new comp of course....but Will I have to take off every wire connected to the comp on the 89 and router them accordingly on the 91? or is there diagrams for wich wires I could just solder to harness on my 89 2.2 computer...I see the harnesses are different so it really scares me. I assume the LM has to be changed as well?

[Una]

Yeah, just change the crank and order up 2.2 pistons.. I did this for my GLHS's new engine. Came from a turbo van I parted out..

[22dodge]

Quote:

Originally Posted by Jack's Dodge I want to change the charateristics of my 2.5 block, and make it a 2.2. From what I understand, the pistons are the main difference. Is there anything else. Wanted to get Mahles and new rings, and get moving.

depends on what year engines you are talking about. 2.5 from 1986-1988 is approx ½" taller block. it uses the same pin height as a 2.2 but has a longer stroke and longer rod. on 1989 and new 2.5 vs 1989 and newer 2.2 the blocks are the same and so are the rods, however the pin height and stroke are different. all the wiring is the same between a 2.2 and a 2.5 only difference is the computer programing (which is very minimal) Infact, I frequently have installed a 2.2 where a 2.5 was and visa-versa (TBI) the electronics operated flawlessly in this swap.

[bluneon]

dont forget about the counter weights. and to plug up the oil hole for them. 0 oil pressure is a no no.

[2point5]

comon block
if a 2.5L and you want 2.2


you will need a 2.2 crank and pistons hit up the j-yark for some cheap ones you can leave electronics the same i have not noticed any differance

[Alberta_Daytona]

sweet! so could I then just swap the entire engine from my 89 shelby (2.2) to my 91 shelby....doing research shows both same common block engine.

would there be any advantage to swapping over electronics...would it generally run rich?

If I can just swap over the engine I think im doing an engine swap next weekend.

[Jack's Dodge]

Thanks for all the info. I'd rather order some new Mahles personally. Want a fresh start for the block. Considering having a mild rebuild done: new piston rings and berrings, possibly have it balanced).

[phantomrt]

I smell another debate of which is better 2.2l or 2.5l. LOL

The difference is only the crank and pistons just as everyone else says. I wouldn't worry about computer programming as far as fuel goes because the adaptive fuel trim does a good job of getting that right where it belongs. The issue I see is in the spark advance programming.

Someone correct me if I am wrong, but the 2.2 has a higher compression ratio than the 2.5 due to the 2.5's deep dish pistons. When they made the "high-torque" 2.5 in 1991, they did that by making the spark advance much more aggressive. They probably did it to the fuel curve too because those hi-torque computers dump the gas in pretty heavily at WOT. Aggressive spark advance + higher compression ratio = detonation prone. Run good gas and an intercooler and you'll be fine for sure.

[ThreeTurbos]

u could have a VNT/2.5t1 90-91 sbec reprogrammed to run a 2.2 non vnt...

id run a 2.5 on a 2.2 calibration but id def use a big cooler like was said

[Jack's Dodge]

Quote:

Originally Posted by phantomrt I smell another debate of which is better 2.2l or 2.5l. LOL

Personally, both have good points. This is my cheap way of making a 2.2 commonblock. Period. Rather than seach for a 89+ t2, just get a T1 and move things around. Do a rebuild in the middle, and you have a new T2 block with stout internals. The cast crank is not an issue.

Quote:

The difference is only the crank and pistons just as everyone else says. I wouldn't worry about computer programming as far as fuel goes because the adaptive fuel trim does a good job of getting that right where it belongs. The issue I see is in the spark advance programming.

So, you basically need a GHLS computer along with rewiring for the AIS. That takes care of the conversion for an 86.