m30 3.5 or m50 2.5?

Post Sun Oct 14, 2007 9:16 am

in your opinions which is the better engine, might help me deside which to go for both seem good for turbochargeing the m50 is a lil better on fuel and can be had cheaper but the m30 has more power.

chris

Post Sun Oct 14, 2007 9:26 am

M20 was not available in 3.5 form, Do you mean M30?

Post Sun Oct 14, 2007 9:41 am

doh thats a bit more like it, shouldn't stay up late playing forza2 and halo3.....

chris

Post Sun Oct 14, 2007 9:47 am

Very good question. One I have asked. Other considerations are the weight of the respective lumps, ease of conversion and cost. The m50 needs a trick outlet manifold, though there are a few more about now.

Would be canny to see pod runs for both engines...

Post Sun Oct 14, 2007 9:49 am

Fritz now do a full system specifically for the M50 conversion Nathan, Approx Ã‚£1200 iirc. Not bad for a 6 branch & system.

Post Sun Oct 14, 2007 10:02 am

well my plan is to use the std set up as much as possable then move on to the turbo set up and since its not going into a e30 i'm expecting some cut and welding work and i've built exhaust systems before( manifold back) so making something work shouldn't be too had just need to watch out for the steering systems.

the cost wil be roughtly the same as i'm looking to buy a whole car to take bits from, and i can make everything 1st so its easyer to fit back, the only problems i see is sump clearance, the clocks( use the bmw one a totaly new part or the std one i have) and driveshafts( probbly a custom one so simple enough)

chris

Post Sun Oct 14, 2007 12:39 pm

I would go for the m50 the m30 is an old heavy engine.

Post Sun Oct 14, 2007 5:57 pm

ive an m50 in mine and its good,but i cant compare it to an m30 as ive never been in one,but either way u wont be disapointed,m50 sounds amazing in my opinion

any excuse to put a pic up lol

Post Sun Oct 14, 2007 6:07 pm

I'd love an M50, they just look so right in an E30 bay.

Post Sun Oct 14, 2007 6:55 pm

i've had a 520 and it did sound sooo good even with the autobox sapping any fun the engine was trying to create, whats the most anyone got out of a std engine. its so annoying theres 3 or 4 525 spares or repairs on ebay that i don't have the money for or space for yet

chris

Post Sun Oct 14, 2007 11:45 pm

M30 is a heavy one, but VERY torquey. not having been in an M50/52, I can't compare, but don't twin cams need to rev more to get the same power, hence usually having a higher redline (I'm thinking japcrap here because i have no experience with Euro stuff)

Been in a 520 and that seemed to go fairly well...

Horses for courses.

Post Mon Oct 15, 2007 2:06 am

An M30 has the torque an M50 can only dream of but if you like fast revving smoothness the m50 might be the way to go.

IMO anything less than a M52 is not worth the effort as far as a swap goes, M30 over M50 but M52 over M30. If you plan on rebuilding the engine before a swap the M5x can have the capacity bumped up using parts from the US E36 M series or M54.

Post Mon Oct 15, 2007 11:11 pm

why not go m52 instead of m50? Same amount of trouble - more torquey and can easily mod up to 230bhp!

Post Mon Oct 15, 2007 11:58 pm

Quaser wrote:why not go m52

The trouble part is finding a good one!

Post Tue Oct 16, 2007 7:34 am

and getting one as a whole car as cheap as e34/e36's

chris

Post Tue Oct 16, 2007 11:43 pm

cheap safe 200bhp or risky expensive 230bhp..your choice!

Go to all the effort to get m5x in and running, then,oh shit must take it out because my nikasil block is bollox

m30 is old style tappety single cam,

quote,"2.5 litres of twin cammed rightness" unquote

Post Wed Oct 17, 2007 2:18 am

brian325i wrote:cheap safe 200bhp or risky expensive 230bhp..your choice!

Go to all the effort to get m5x in and running, then,oh shit must take it out because my nikasil block is bollox

m30 is old style tappety single cam,

quote,"2.5 litres of twin cammed rightness" unquote

i wouldn't be swapping any engine without knowing its history and how it ran be previously..... thats asking for trouble nikasil block or not.

Post Wed Oct 17, 2007 2:50 am

brian325i wrote:ive an m50 in mine and its good,but i cant compare it to an m30 as ive never been in one,but either way u wont be disapointed,m50 sounds amazing in my opinion

any excuse to put a pic up lol

looks a quality install there did you do it yourself?

Post Wed Oct 17, 2007 10:40 am

d6dph wrote:Fritz now do a full system specifically for the M50 conversion Nathan, Approx Ã‚£1200 iirc. Not bad for a 6 branch & system.

Thats a disgusting amount of cash TBH.

I think m30 if you want a cheaper easier conversion. best bet for the m30 is to pickup an auto engine, and then put the manual box on it.

Bottom ends are preety much nuke proof, and they have been known to hit over 500bhp on a suicide run to see how much they can take.

They are also lower compression, so better for forced induction.

wiring is simpler as well.

bad part might be that it will be heavier on fuel.

sound wise its down to taste. but there's less m30's with a note out there than the 2.5's, so my vote goes to the 3.5.

The m30 is a hell of a lot more torquey, but max's out rev wise pretty early. Still a 200k average maintained 635 will woop a seat 2 ltire turbo on the motorway, and will still hit the 150 mark.

2.5's have a nice induction note though!