I have a question about a potential issue I may encounter in the future with ME7 and I wish to be prepared. If my ECU/CEM believe I have a 2.4T5 engine, but internally it is closer to 2.0T or at best 2.3T, would this throw off the air/fuel calculations much? To simplify, would the ECU correct these differences or would it require re-tuning?
My project is to use a 2.5T head with a 2.3T block, or if I cannot find a 2.3T block, I may use a 2.0T LPT block. I lose between 200 and 500cc of volume. I don't exactly like the 2.0T block, because it is higher compression 9-9.5 or so, I believe, and is thus an LPT block.
First goal is 300hp, and I see it has been done with a 2.0T block
https://www.youtube.com/watch?v=aDATrv_8tsc. But only after I get it to work stock just to be sure it works.
On the question why do I need to make the ECU think it's a 2.4T5 or 2.5T2? Well only because of the dual VVT setup, and only 2.5T2 and 2.4T4/T5 have this setup on P2(right?) and I cannot find a 2.4T5 block, thus anything with a 81mm bore will do it for me.
There should not be any major problems with ECU after block swap even from 2.5 to 2.0.
Any minor problems you will fix doing tune.
I would compare 2.0 and 2.5 original soft and look at maps related to engine displacement like KFMDS (engine drag). But i guess you would be ok without touching that either.
The most important is fueling and ignition! You should tune it in the first place.
2.3T5 Block shim it and reseal it up. if you're pushing power do rods pistons and new bearings
I agree with resealing! It is a must! All rubber sealing (valve seals, cam seals, orings etc.) in an old engine are plastic, brittle shit and will fall apart after few WOT pulls
But for 300HP stock internals in 2.3 engine are more then enough. I abuse my 2.3 with 19T turbo (around 330HP) at 1,4bar peak falling to 1,15 at redline and by abuse i mean literally abuse! Like doing tens of pulls 0-200 one after another! Flying at 200-250kph WOT for 50-100km! Turbine is literally shining like a bulb for 30-45 minutes constantly! And i do it for 2 years now and engine is perfectly fine
And my fueling is set at 12,0 AFR enriching to 11,8 by ATR on longer pulls. No need for any crazy fuel dumping like 10,7 at short WOT pulls
Ignition @ 16-17 degree at 6000rpm. No knocks.
I was even thinking about putting EGT gauge but finally i gave up because whatever EGT it's ok so why bother
Those 2.3 engines are insanely bulletproof
