RFO: Gaining about 10-15HP for M20B20, opinion?

[nsbone_1988_520i]

Hi,
Firstly RFO= Request for opinion.

Well, i hv this idea to swap crankshaft, conrod, pistons from e30 M20B23, into my M20B20 block and gaining about 10-15HP and some increase in torque value, without changing engine number, legal, and roadtax rate at 2.0L... it'd probably not much of effort in next head gasket/clutch replacement...

what do you guys think...

of course 2.5L is way to go,


thanks in advance..

[Jon K]

Just leave it alone. It'd cost too much money to justify 10hp. You obviously need an M50 motor, but you said you can't afford the tax or something. Just wait until you can.

[nsbone_1988_520i]

Just leave it alone. It'd cost too much money to justify 10hp. You obviously need an M50 motor, but you said you can't afford the tax or something. Just wait until you can.

Anyway, i am thinking of doing this on my own. So I'm just wondering if 10HP will make noticeable different on e34. All i need just donor 2.3L engine for swapping internals.

What say everyone?

[Hypr5]

how many hp does the m20b20 put out? Somewhere along the lines of 125 hp, right? I'm pretty sure that the m20b23 (i believe its 159hp) is still quite a bit less than the me20b25 and even that is slow slow slow. I wouldnt sink ANY money in the m20 engine for a 5er simply because even with 170hp, it's still underpowered! You may notice the gain, but to be honest I don't think it will be anything that will make you say "wow I'm glad I did that..."

[632 Regal]

10-20 hp in such an underpowered car will make virtually NO difference. You might seriously want to look into bigger engine options but I do understand how thay tax you on that. do they inspect the car and the engine casting numbers to see what engine the car actually has?

[Jon K]

I wonder if they're smart enough to tell an M30B35 from a M20B20. Intake manifolds look similar... You could grind the castings down and maybe forge your own