Been looking into upgrading my original m20.
It's got a few bits done already and now I'm starting to look at the internal side of things.
I was told the m47 diesel crank is a good swap to help develop power.
For the pound/ power ratio would this be beneficial or am I wasting money on trying to hike the power of the m20 in N/A form; or more financially cheaper/ easier to boost the m20?
M20b25 N/A vs Turbo
Moderator: martauto
M47 crank is a 4 cylinder and is used on M42s to increase stroke I believe.
An M21 diesel crank is what you want for a 2.7, have a search been covered many times.
Depends how much your willing to spend and what power you want.
A set of ARP headbolts and an M20 is good for 400hp with plenty of boost.
An M21 diesel crank is what you want for a 2.7, have a search been covered many times.
Depends how much your willing to spend and what power you want.
A set of ARP headbolts and an M20 is good for 400hp with plenty of boost.
Oh sorry my mistake.
I was told it was the m47 which is why I didn't understand where I'd get the extra power from.
The m21 crank conversion then, is it a worth while modification or from the upgrades you gain and the cost of it not worth it in people's opinions?
Ah I wasn't aware that the m20's were capable of 400 on standard internals.
Well power wise I'd ideally be looking around the 300 mark to keep it relatively reliable.
Money isn't really an issue because of it been a track car already it's off the road; but on the other hand I don't want to be going into spending £4-5k either.
I was told it was the m47 which is why I didn't understand where I'd get the extra power from.
The m21 crank conversion then, is it a worth while modification or from the upgrades you gain and the cost of it not worth it in people's opinions?
Ah I wasn't aware that the m20's were capable of 400 on standard internals.
Well power wise I'd ideally be looking around the 300 mark to keep it relatively reliable.
Money isn't really an issue because of it been a track car already it's off the road; but on the other hand I don't want to be going into spending £4-5k either.
Any idea what sort of power you'll push out of an n/a?
What I mean is for example...
Turbo'ing a m20 to 300bhp reliable- £4,000
Modified m20 n/a to 230bhp- £2,000.
For the extra 70 horses id rather save the £2k and go for either HSD MonoPro coil overs for instance.
What I mean is for example...
Turbo'ing a m20 to 300bhp reliable- £4,000
Modified m20 n/a to 230bhp- £2,000.
For the extra 70 horses id rather save the £2k and go for either HSD MonoPro coil overs for instance.
I'm currently having an M20B28 built using an M52 crank. Easiest and newest crank to get hold of these days, the earliest small webbed M52 crank even clears the early M20B25 High Comp pistons without modding them unlike the later cranks.
I think it'll cost you a bit more than £2000 though to get to 230bhp from a N/A engine. I'm not sure mine will make that and I've probably spent more than £2000, mine is a total rebuild though, new shrick cam, all shells, rockers, rings etc etc replaced.
Turbos do give the best value power, check out Indys touring thread in the pics section, he's done an M20B25 turbo build that wasn't crazy money.
I think it'll cost you a bit more than £2000 though to get to 230bhp from a N/A engine. I'm not sure mine will make that and I've probably spent more than £2000, mine is a total rebuild though, new shrick cam, all shells, rockers, rings etc etc replaced.
Turbos do give the best value power, check out Indys touring thread in the pics section, he's done an M20B25 turbo build that wasn't crazy money.
