stroker kits estimated power numbers

[Bastijn Van Weynsberghe]

can someone help me I'm looking to do a stroker build on my M20B25 and would like some additional information.
I know you can do a 2.7 with a minimal budget and get around 200hp but there are also 2.8, 2.9, 3.0, 3.1 options but can't find some estimated power figures for those can someone give me an estimation of what power I would be looking at for the different stroker kits? thanks in advance!

PS: I know an engine swap is probably cheaper but would like to keep the original engine

[Von Soman]

I do not know those power numbers for the 2.8 ect, etc stroker kits but you mentioned Original engine. Keeping the M20 2.5 with motronic ECU in California with working AC should not be underestimated unless your building a race car. The 2.7 bottom with the 885 head and a chip, 19lb injectors,272 cam is my eventual path. its a nice motor and pulls good enough with a 4,10 LSD.

[Bastijn Van Weynsberghe]

I have a 4.10 diff and a recently rebuild M20B25... I'm exploring these options for further down the line. I'm also from Belgium where engine swaps and turbo builds aren't legal (engine swaps in rare occasions are) so I want to build the original engine because they don't notice at the inspection. also sadly I have a non AC version....

[hasa]

One of the cheapest mods is to get the early "C38" 2.8 litre crankshaft, combine with 130mm rods and low skirt version of B25 pistons. Block must be skimmed 0.5mm. Youll get 2.8 litre base engine.

[digger]

can someone help me I'm looking to do a stroker build on my M20B25 and would like some additional information.
I know you can do a 2.7 with a minimal budget and get around 200hp but there are also 2.8, 2.9, 3.0, 3.1 options but can't find some estimated power figures for those can someone give me an estimation of what power I would be looking at for the different stroker kits? thanks in advance!

PS: I know an engine swap is probably cheaper but would like to keep the original engine

Unfortunately it doesn’t work like that, the difference is predominantly in the torque. Unless you get a really good cylinder head the 2.8-3.1L will peak as far as hp is concerned at about same peak number the reason being the stock head and crab intake manifold is way under done for these big capacities it simply chokes it.

The bigger the engine the more low end / mid range / peak torque all else equal being equal.

dont attempt the bigger engines ?2.9L without some seriously good cylinder head work decent camshaft and good indcuton kit, otherwise it will be great at bottom end and midranage and die at topend with a narrower powerband. You wont get a good cylinder head from the "big advertisers".

[ForcedFirebird]

Unfortunately it doesn’t work like that, the difference is predominantly in the torque. Unless you get a really good cylinder head the 2.8-3.1L will peak as far as hp is concerned at about same peak number the reason being the stock head and crab intake manifold is way under done for these big capacities it simply chokes it.

The bigger the engine the more low end / mid range / peak torque all else equal being equal.

dont attempt the bigger engines ?2.9L without some seriously good cylinder head work decent camshaft and good indcuton kit, otherwise it will be great at bottom end and midranage and die at topend with a narrower powerband. You wont get a good cylinder head from the "big advertisers".

This.


I have customers with stock crank b25's, stock throttle and valves making 200+whp (190's wtq), and also 2.9's making ~210-220 (albeit 200+ tq). The rotating assembly is the "dumb" part of the engine. All the power comes from before and after the pistons. My race car has used 84mm pistons, used 81mm crank, used 130mm rods, used head with 272 cam and puts down 180whp/180wtq (fresh rings/bearings/valve job/machining).