e30 engine conversion.

[yng_750 247]

just out of interest i have been looking at a few project threads about e30s getting m52 conversion.

it seems many people are using 318i 4cyl as the base car.

is this just a price thing?

i would presume 325is would have bigger brakes and a stronger gearbox/diff. not to mention better interior fitout etc

or is this not a really noticeable difference?

also is the box off a 318 really strong enough for a 2.8, or do people again make do due to price.

[dubman 39]

Interesting, is this based on Bimmersport or USA sites?

[_ethrty-Andy_ 2130]

just out of interest i have been looking at a few project threads about e30s getting m52 conversion.

it seems many people are using 318i 4cyl as the base car.

is this just a price thing?

i would presume 325is would have bigger brakes and a stronger gearbox/diff. not to mention better interior fitout etc

or is this not a really noticeable difference?

also is the box off a 318 really strong enough for a 2.8, or do people again make do due to price.

Basically:

325i or M325i: likely to have better interior and options, has big brakes, axels and diff (usually LSD), needs whole drivetrain swap forward of diff

320i: not as good options, has big brakes, has small diff and axels, has linkages driveshaft flywheel etc you need, needs gearbox swap

318i or 316i: likely to have little to no options (so lightweight), has small brakes diff and axels, has the gearbox you need, but requires 320i manual facelift linkage driveshaft flywheel etc

and 325iS doesnt exist in NZ, thats a USA badge for well/fully optioned 325i

You need to use an M4x or M5x gearbox bacause its on the correct angle. An M20 M30 etc one will physically work, but the shifter is all on the piss. having driven a conversion with this, i dont recommend it, its awkward to drive.

Some people will no doubt say otherwise what worked for them!

Hope that helps

[Ahmedsinc 414]

just out of interest i have been looking at a few project threads about e30s getting m52 conversion.

it seems many people are using 318i 4cyl as the base car.

is this just a price thing?

i would presume 325is would have bigger brakes and a stronger gearbox/diff. not to mention better interior fitout etc

or is this not a really noticeable difference?

also is the box off a 318 really strong enough for a 2.8, or do people again make do due to price.

I'm assuming you're referring to the E36 318 box? If so, it's the same Getrag box as the 325i. Admittedly not as strong as the ZF but apparently still good for up to 300hp, according to threads I've seen elsewheres

I imagine these days the prices of manual E30 325s will have a lot to do with 318s being the base of choice. Most of the B25s I've seen would be criminal to tear apart and rebuild, especially the Ms. Probably not much help, but my 2c worth

[polley 916]

You need to use an M4x or M5x gearbox bacause its on the correct angle. An M20 M30 etc one will physically work, but the shifter is all on the piss. having driven a conversion with this, i dont recommend it, its awkward to drive.

you can just cut and reweld the shifter

m30 gearbox wont work

[e30ftw 410]

If you are looking at doing an m52 e30 swap then I strongly recommend reading the M5x - E30Zone Wiki.

Every component of the swap and branches off into some great info. Wish I came across it last time I did it (probably didn't exist tbh)

There are heaps that have used getrag 240 (e30 m40) gearbox behind m52 with no issue, I would say due to it's low cost / simplicity that it bolts directly in with no modification and using mix and match of OEM parts.

Edit* linked wrong page

Edited August 13, 2013 by e30ftw

[dubman 39]

http://www.rmeuropean.com/bmw-e30-m50-swap.aspx

here's another one, don't know how true/applicable most of it is though

[polley 916]

Heaps of the wiring diagrams online are incorrect. A g240 will be fine.

[yng_750 247]

cool. heaps of good info there.

i just thought it odd that people would go from a 318i convert it then spend heaps of money upgrading the trim etc to 325 levels. most would have been cheaper to start with a better car.

The only other thing that got me was people spend more on the m52 then move it back to obd1 and get rid of the vanos etc.

Not planning to do the conversion any time soon but a 2.8 screaming in an e30 coupe makes me tingle in certain places.

[polley 916]

Apart from diff, brakes, and front struts. Pretty cheap / easy to swap over.

[yng_750 247]

seems my eyes are melting out of my head after all the reading i have been doing on this subject. seems most people who undertake this swap are generally literate which makes reading forums alot easier.

So from what i have gathered if i went ahead with this swap i would go for the m52b28 single vanos.

based on having more power and torque, i wouldnt go twin vanos as they tend to cost more and i dont believe the power gain is worth the rebuild cost vanos would possibly need. (similar to picking up some s52 cams for the earlier motor)

The biggest thing that im not quite getting is the ecu side of things. it seem i have two options.

1. use m52 ecu but get it reflashed to exclude EWS, asc, abs(maybe), secondary o2, cats etc.

2. convert the entire loom and sensors to obd1 out of a m50b25 single vanos.

seems most people go for the second but it seems much simpler and cheaper to go with the retune, am i right or missing something.

The next biggest thing seems to be the exhaust which most people modify the down pipes extensively to fit around the steering, is it then really worth redoing the rest of the exhaust or with an e30 525i system flow well enough to support the engine. (i would probably be going for stealth over loud), would get rid of the cats of course.

Lastly the brake booster seems to have heaps of clearance issues, i have seen solutions but they all seem to be LHD vehicles, am i right that RHD still has the booster on the left but has an extension bar going under the dash? if so how does this affect connection of a modified booster?

[_ethrty-Andy_ 2130]

seems my eyes are melting out of my head after all the reading i have been doing on this subject. seems most people who undertake this swap are generally literate which makes reading forums alot easier.

So from what i have gathered if i went ahead with this swap i would go for the m52b28 single vanos.

based on having more power and torque, i wouldnt go twin vanos as they tend to cost more and i dont believe the power gain is worth the rebuild cost vanos would possibly need. (similar to picking up some s52 cams for the earlier motor)

The biggest thing that im not quite getting is the ecu side of things. it seem i have two options.

1. use m52 ecu but get it reflashed to exclude EWS, asc, abs(maybe), secondary o2, cats etc.

2. convert the entire loom and sensors to obd1 out of a m50b25 single vanos.

seems most people go for the second but it seems much simpler and cheaper to go with the retune, am i right or missing something.

The next biggest thing seems to be the exhaust which most people modify the down pipes extensively to fit around the steering, is it then really worth redoing the rest of the exhaust or with an e30 525i system flow well enough to support the engine. (i would probably be going for stealth over loud), would get rid of the cats of course.

Lastly the brake booster seems to have heaps of clearance issues, i have seen solutions but they all seem to be LHD vehicles, am i right that RHD still has the booster on the left but has an extension bar going under the dash? if so how does this affect connection of a modified booster?

for the booster, whatever people say works for LHD cars works for RHD. I used a Porsche 944 Booster which is a direct bolt in swap, i might have had to shorten the rod i think, but easy to doe etc. Plenty of options, various VW boosters are the most common.

the stock M20 headers wont fit on the M5x engine, so you need to get some custom made up. Noone sells RHD M5x swap headers that i know of. I used stock OBD2 type headers, and had them cut and welded etc to fit around the steering linkage. From there I had custom made exhaust made right back, but you could adapt it to then mate up to a stock E30 325i M20 exhaust im sure. but you will probably want to de-cat, and change the restrictive back box, so might as well just do the whole thing custom imo.

to make it run, either solution will work. When i did my conversion noone was doing flashes for OBD2 DMEs at the time that i could find so you either HAD to run OBD1, or make the EWS work some way. im sure some people were doing flashes at the time i just couldnt find them. but thats the way ill be doing it next time around

[polley 916]

What ever ecu you wanna use is up to you, you can make the EWS work if you have all the extra stuff that goes with it. Or get a EWS delete chip for it.

Or just convert to ODB1, and get it remapped. The remap is not necessary though.

Get the M52 tubular manifolds and modify them, its not actually that hard, not a lot needs changing. The standard 325 exhaust will flow fine for it, have used one before when doing a m50 swap on the cheap. If it was me I would build a whole new one, its not expensive if you do it your self.

The last 3 m50 swaps I've done I've used double diaphram booster from an E32 / E34. Slot the holes on the bracket so it moves the booster down and across - leaves heaps of room between the manifold and booster. Use the 25mm master cylinder from the E32 / E34 as well, makes the E30's crappy brakes a lot better. I've always put a proportioning valve in for the rear brakes otherwise they tend to brake a bit hard in the rear when using the 25mm mc.

Swap the pivot / linkage from the e30 booster to the e32 booster (e30 is shorter), and it lines right up with the extension bar under the dash.

You can use the Vw golf booster, but its small and you end up with sh*t brakes.

[hybrid 1042]

You can use the Vw golf booster, but its small and you end up with sh*t brakes.

All your other information is correct accept this assumption. Works more than fine even moving a BBK, upgrade the MC though to 25mm. All your face in the windscreen needs.

[yng_750 247]

will point out hybrid is at 6666 posts, not sure what to make of that.

getting very excited by the possibilities here.

seems to me if i get a running e30 and an e36 donor car i can use the e30 as a daily and apart from the exhaust if i do everything right could get almost everything ready to go so the car is off the road for minimum amount of time.

has anyone had any issues with Certs?

seeing as its standard stuff i doubt they will want driveshaft hoops etc. possibly just want better brake pads and rotors.

[polley 916]

All your other information is correct accept this assumption. Works more than fine even moving a BBK, upgrade the MC though to 25mm. All your face in the windscreen needs.

Well I will have to admit, I've never used the vw booster. Heard a lot of complaints about it though.

When it comes to cert I doubt they will say anything about needing better brakes. You will need drive shaft hoop(s) though.

Edited August 18, 2013 by polley

[antil33t 90]

I spoke to a Certifier, and he said I'd need a hoop (seriously wtf for though) but not a brake upgrade. Just as long as the rotors and pads looked good.

[Allanw 1068]

The brakes part of the cert process is easy to pass.

I can't recall the details, but my VW van with it's stock UNvented front discs pissed in, and it has double the HP and very close to 1.5 times the RPM to play with now.

E30 would have no issues.

[hybrid 1042]

All modifications to the braking system including diaphragm, master cylinder, lines and bias propertioning will go through a certification process.

Mine went through the below process from cold. My pad compound at the time almost failed it because it hadn't heated up enough however.I have since changed to a more advanced compound which doesn't need any warm-up before, they can now perform well past this level.

All detailed here in Section 2.4

http://www.lvvta.org.nz/documents/standard...ing_Systems.pdf

(a) modified production low volume vehicles which have

attained an increase in engine power output from the

original vehicle manufacturer’s specifications of between

20% and 50%, or have any modifications to the service

brake system, or have any modifications which result in a

change in or relocation of weight or centre of gravity, must

achieve:

(i) 3 consecutive cycles from 100 kph to standstill

each at an average deceleration of not less than

0.65G; and

(ii) within a total time of 2 minutes from the start of

the first cycle to the completion of the third cycle;

or

( all scratch-built low volume vehicles, and modified

production low volume vehicles which have attained an

increase in engine power output from the original vehicle

manufacturer’s specifications of more than 50%, must

achieve:

(i) 5 consecutive cycles from 100 kph to standstill

each at an average deceleration of not less than

0.65G; and

(ii) within a total time of 3 minutes from the start of

the first cycle to the completion of the fifth cycle.

[Nobimmer 694]

You can also use a booster from an early ugly 190e merc. Slot the holes and it bolts straight in

[yng_750 247]

just looking at a few options for e30s.

is there any disadvantage to starting with an e30 automatic, specifically a 318i auto

im guessing the diff might have a funny ratio and the cluster have auto stuff on it but would that be the full extent of issues i would face.

[e30ftw 410]

Nothing much really,

Diff is easy to change just find a medium case LSD.

You have wiring to change and the clutch pedal to add, relatively easy to do did that on my last e30 with the m50 as it started as a 320i auto. Ended up with 3.64LSD, 325i suspension and converted to manual. Cluster is the same between auto / manual except the rev gauge may show red line differently..

[yng_750 247]

Cool.

is the clutch pedal its own mount or is it need a complete pedal box change.

little bit strange but on some very expensive builds i have seen online (hybrid) i havent seen anyone put in a floor mount pedal box, considering the effort some go to with the booster.

seems an adjustable sytem would suit big brake kits better.

Only other thing is will the 4cyl rev counter read off the 6cyl engine ok?

seem to be no limit of questions these days haha.

[yng_750 247]

Also small and medium case diffs interchange on the mounts?

[e30ftw 410]

Pedal box between auto and manual is the same, You just need the longer bolt and clutch / brake pedal from a manual car and slide it in to replace the auto brake pedal. Master cylinder mount is already there.

Maybe because the Brake booster is on the opposite side of the car, it's easier to just change the brake booster rather than modify and fit new brake pedal.

I believe there is a coding plug that is required to be changed on the 318i cluster, probably easier to just get a 325i cluster or a damaged one.