best/easiest/most logical swap for e30

[crshbndct 0]

okay.. i am the fool who bought the burgundy e39 with horrific paint off trademe a few weekends ago.

obviously, the m20b20 is not going to cut it.

what i wanna know is, what is the best engine swap for an e30 IN NEW ZEALAND? i mean obviously, a lot of the sites are american or euro, so prices for engines, and parts are different. over there, the best and most economically sound swap is s50. over here, thats a 15k engine.

so what is the best swap to do?

m20b25? doesnt give me enough power really, but is cheap and cheerful

m30b35? affects handling, but lots of power and tq.

m50b25? is it a hassle with the rhd steering column getting in the way of exhaust?

m52b28? as with m50, as well as is it a more expensive engine?, obd2 wiring not an issue, have heard they are harder to get power out of? is the extra .3l really worth it?

what about something japanese? sr20? 4g63 with starion gearbox? ( i have a spare box, and engines are cheap as, but i see them as a bit of a brute compared with the silky smooth bmw 6)

i really dont want a turbo though. would like about 220hp or so. my car doesnt have ac, power windows, or powered sunroof, and being a 2dr is pretty light so that should be plenty.

i will probably be megasquirting the car, regardless of what engine i put in, i have just got myself a ms3, and the car was pretty much bought to have something to put that in.

much like with rb engines being the swap of choice into cefiro's laurels etc, what is the best swap for my e30?

[Silver Fox 43]

Road or track?

[e30plz 1]

MS/Turbo the M20B20.

[AN E30 Fan 1]

Easiest swap would be the M20B25 but the most logical if you are going to do a swap but if you are wanting a reasonable amount of power, the M50B25 would be the best option.

Have you thought about stroking out the engine to 2.7L or 2.8L?

If you were going to do a M20B25, while to motor is out of the car I would rebuild it to 2.7L or 2.8L.

I haven't done any of these but honestly from what I have read the M50B25 is the most cost effective way of having more power in your E30. However, a lot of people on the forum have done or are doing this swap its become ALOT more popular over the last 8 months in NZ, if you want to do something different and still want a decent amount of power/torque I would go for the 2.7/2.8L M20.

Sounds like I have mixed opinions re reading this

[crshbndct 0]

yeah its just a road car. possibly a thrash around the track once or twice a year.

right now, i am able to get a m20b25 in the car for under $300, which is looking more and more like what i am going to do and just stick with that till i can get an m50 and spend some real money on it. engine = $250, mate said he would throw it in for $50 and a box.

but that doesnt really make it a fast car. just a moderatly quick one.

my total budget is about 3k, there are m50 engines available for $1000, so is this reasonable, or am i better turboing the m20?

[tibbs.james 1]

for 3k

LSD, Bilsteins, H&R springs, m3 front bushings + solid subframe mounts and new trailing arm bushings.

plenty of fun can be had with relativiley little power. Seems whack I know but having heaps of power is going to suck without and LSD and some kind of decent way to get it to the ground.

Good luck with the project 24V E30 swaps and being documented on here every other week so have a search and go nuts.

[antil33t 90]

I'd rather do an M50 swap but I went from M20B20 to M20B25, that was very very easy, so long as the engine is the same engine management as the one that it's replacing.

Though, that is a cheap power upgrade, B20 to B25 is day and night (in power difference)

[APT 179]

I would go to M50 i went from a M20B20 to a M20B25 and you get sick of it pretty fast even though the power gains are alot more noticable between the two.

I am in the same situation as you and do not know where to go from now with the upgrade to the new engine. Most cost effective would be m20b25 if i had about a 12 grand limit i would be putting an F20c in the car, but thats just me.

[mark247 38]

People who have gone from m20b20 to an m50b25 say it's a huge improvement. I went from m20b25 to m50b25 and I've found it makes little difference. Of course it's a better engine, rev's quicker, and it does have slightly more power..but in reality it isn't a breathtaking difference. I did it more for the bling bling.

[crshbndct 0]

yeah see this is what i was looking for.. thanks guys.. possibly m20b25 turbo then? could it be done properly on a cheapish budget? (3k?)

[mark247 38]

Are you doing your own labour? Remember if you go turbo properly you are going to have to go aftermarket ecu, take the head off and install a thicker headgasket.. etc etc. $3000 wont go far, esspecially if you are a newbie ( I'm not sayin you are, I'm just sayin )

[hybrid 1039]

m20b28

ask Ray/HellBM, hes just finishing testing on his prototype at the moment. Product should be open for busniess soon.

[Forrest 35]

m54b30 on a link, will be my next powerplant for the E30 race car to be. 300hp +

Edited May 23, 2010 by Hellpina

[APT 179]

what gearbox would u use on that nathan?

[Forrest 35]

Same as any m5x swap. Best to use a E36 box though because I know of two 260's going bang already with standard m52 power.

[APT 179]

interesting.... out of a 330i right?

[Forrest 35]

^ Yep. I know of about 4 M54 swaps currently in planning/construction stage, are a couple complete racing also.

Including Dave (Silver Fox's one)

Edited May 23, 2010 by Hellpina

[APT 179]

Awesome just another engine all together to consider now. haha

[crshbndct 0]

okay the plan has been set in motion..

i have decided on an m30. cheap as sh*t, tough as sh*t, and powerful. i will be spending the money i save over doing a more expensive swap on suspension and brakes.

so.. some questions:

1) do the m30b35's we get in new zealand have the 93.4 bore/84 stroke or did we get the longer stroke smaller bore models?

2)if the above is true, is it possible to put in a longer stroke crank and get 3.78 litres out of it, and 11:1 cr, or am i high and that will just shove the pistons up through the head?

3)does anyone know what the intake port sizes are? i have access to several motorbike engines and was thinking about making some itb's (only once the engine is already in and running)

4)before the motor goes in it will be getting a light rebuild, rings, bearings, mild porting, gaskets, and probably a cam. does anyone know the head gasket thickness?

my goal is 250hp at the motor. with a aftermarket ecu, cam, porting, possibly itb's, decent set of tuned headers, and definitely a short runner intake if not itb, will i get this figure? given that the engine should make 218hp stock.

i decided on it for cost, torque(to which i have a serious addiction), and the fact that the engine is very unstressed at about 60hp/l, which leaves much scope for more.

as far as the weight, doing it this way will leave far more in the budget for suspension and brakes, to the point where this engine will probably actually allow me to have a much better handling car.

epic build thread coming soon. gotta get paint sorted first though its a bit of a cop magnet.

[Silver Fox 43]

I've got 190 at the wheels, with cam and light head work only. Hope to hit 200 plus with headers soon.

Edited June 6, 2010 by Silver Fox

[AN E30 Fan 1]

Theres a guy on here doing an M30 swap into an E30 at the moment check it out in the "Project" section.

Try to mount the M30 as far back as possible so don't have too much weight over the front wheels and it will make it easier to mount the radiatorwith all its hoses..... or intercooler

Edited June 6, 2010 by AJ_D

[BM WORLD 1261]

if using a m30 block you will need a gearbox to suit .

here is a pic of the m30 engine bore stroke ratio's etc

use a early 1979 to 1982 m535i 635csi or 735i block fit a later 1983 onward 635csi 735i 535i crank into it

i think you will go over your 3k budget though with this conversion

[topcat 11]

okay the plan has been set in motion..

i have decided on an m30. cheap as sh*t, tough as sh*t, and powerful. i will be spending the money i save over doing a more expensive swap on suspension and brakes.

so.. some questions:

1) do the m30b35's we get in new zealand have the 93.4 bore/84 stroke or did we get the longer stroke smaller bore models?

2)if the above is true, is it possible to put in a longer stroke crank and get 3.78 litres out of it, and 11:1 cr, or am i high and that will just shove the pistons up through the head?

[qoute]

yes it is possible to use the early 635csi blocks with the latter 86mm cranks. (its been done,namely me)

alittle bit involved but doable. using the latter e28 (b34) 3,5 heads will keep the CR higher as using the b35

heads will lower the CR by about .70 . atho the b35's do have bigger valves-tradeoff's somewhere.

for the cost of the whole project,stick with a late model e28 3.5 10-1 compression and with a cam will be most sufficiant it torque and throttle response

i have a m30b35 (9.2-1) engine('89-93) complete with loom and computer to sell

also have a m30b34 (late e28)10-1, 3.5L. add the latter loom and ecu(easily remappable by Gavin)

add headers/cam and it can all be done within your 3k budget and 240hp should be every achievable

be hearing from you,marty

[crshbndct 0]

i thought that the two bore stroke combinations were 86borex92stroke and 93.4x84

if its 92x84 thats fine for me.

so i will probably just put in the engine, leave it totally stock, and then once other things like suspension and brakes are sorted, look at some power upgrades. i want to have the engine in before i start looking at susension, as there is not much point tuning the suspension for a certain weight then changing it.

no i will not be turbo'ing it.. would be a great car then, but as a street driven car i am sure 340nm/1100kg will be enough fun as it is

[topcat 11]

i thought that the two bore stroke combinations were 86borex92stroke and 93.4x84

if its 92x84 thats fine for me.

so i will probably just put in the engine, leave it totally stock, and then once other things like suspension and brakes are sorted, look at some power upgrades. i want to have the engine in before i start looking at susension, as there is not much point tuning the suspension for a certain weight then changing it.

no i will not be turbo'ing it.. would be a great car then, but as a street driven car i am sure 340nm/1100kg will be enough fun as it is

the 635csi blocks are 93.4x84. also called the m90.

m30 blocks (3.5L) 92x86.

i'd deffinatly use the e28 3.5L with the later loom and ecu. a big step up from the e28 in tidyness and tunablity