E9 with M3 engine

Candia4441

Well-Known Member
Site Donor $
Site Donor $$
Messages
929
Reaction score
311
Location
California
Hello All,
please help, I hope I get a help I need, I am very close to complete my 71 E9 and last week I start restoration of my 73 csi the engine on 73E9 is bad engine and I need to rebuild the engine so I could fined a 2006 Z4 M from accident auction that have a same engine and 6 speed gear box as a M3 the Z4 have only 40K mile on it with very solid and good engine I want to put this M3 engine and 6 speed gear box on my 73 E9 if any one have a experience doing this engine change please give me a advise, what do I look for not to face a problem like E9 original deferential will work with this engine or I have to upgrade that since M3 engine have 333 HP that is a lot for E9 any suggestion I will be appreciated.

I wish the best for all member
 
It's a really big project.
First question, are you planning to do it yourself?
Does the S54 oilpan fit with the e9 front subrame, my guess is that it wont fit.
You'll need to figure out a new brake system, as the stock booster and MC probably won't fit.
Don' t know about the steering, you might have to do a rack and pinion solution.
I don't think the 6-speed will fit in the tunnel, so you'll have to rebuild the tunnel.

I guess you'll need to run an aftermarket ECU, and you need one that can handle the Vanos system.

The stock rear diff can probably handle the S54 if you're not abusing it too much, but to be sure, you'l probably have to upgrade that as well.
 
It's a really big project.
First question, are you planning to do it yourself?
Does the S54 oilpan fit with the e9 front subrame, my guess is that it wont fit.
You'll need to figure out a new brake system, as the stock booster and MC probably won't fit.
Don' t know about the steering, you might have to do a rack and pinion solution.
I don't think the 6-speed will fit in the tunnel, so you'll have to rebuild the tunnel.

I guess you'll need to run an aftermarket ECU, and you need one that can handle the Vanos system.

The stock rear diff can probably handle the S54 if you're not abusing it too much, but to be sure, you'l probably have to upgrade that as well.
Hello,
thank you very much, you have a lots of knowledge, I am not doing my self it is professional guy doing this he never did this kind of work on 3.0cs but I have seen he install this engine on 2002 BMW that was look unbelievable he ask me if I want to do this with my E9 I know oil pan need to be change and oil pump need to be change he told me we may have to go with 5 speed gear box but other than that I do not know what I am getting in to he have a booster pump that will work with that and can you please explain why breake system need to be change or steering system and what is ECU? this guy is professional driver and he fix cars for movie and dos unusual thing that you will not see on mechanic shop he did not explain me much but he wants 20K labor and I have to buy any parts he need but I do not want to get into something crazy that destroy my E9 now price is over 100K I don't want to spend 50K and destroy 100K car.
thank you for your time
 
Hello again,
I have a 2 E9 and one that I start restoring last year it is very close to complete the car and it is 2800cs I spend a lots of time and money on this gorgeous E9 as you know 2800cs rear break is drum my question is how or better question is what do I have to replace to convert it to disk brake, after I take the drum and break assembly and back plate of remains just the hub and to me look the same as 3.0cs, but one have drum and the other one have a disk, will you please explain if you know about it
 
Hello again,
I have a 2 E9 and one that I start restoring last year it is very close to complete the car and it is 2800cs I spend a lots of time and money on this gorgeous E9 as you know 2800cs rear break is drum my question is how or better question is what do I have to replace to convert it to disk brake, after I take the drum and break assembly and back plate of remains just the hub and to me look the same as 3.0cs, but one have drum and the other one have a disk, will you please explain if you know about it

you need to find a trashed 3.0 CS or CSI and buy the whole rear axel from it. You need the trailing arms for disc brakes and the hand brake set up. The swap isn’t rocket science. Here’s a guy selling the whole set up in Germany, not practical for you but will give you the idea of what is required.

Keshav

 
Regarding installing the M3 engine in a coupe:
@Gransin is bringing up some very good points.
Here are the two big real hurdles you must overcome with this conversion: 1- The stock M30 motor sits at a 20 degree angle the S54 sits at a 30 degree angle. You have two choices, keep the S54 at 20 and destroy your oil pick up location or do it correctly and move the block to 30 degrees. This pretty much tosses out your 6 spd as it would be in a grotesque position in your new and very motor home wide drive tunnel you will have to fabricate. To say nothing of the Frankstein shift linkage you would have to fabricate. You could do a Getrag 265 5 spd but then you'd have to build a custom bell housing that 'clocks' the getrag 10 degrees. This is some serious engineering. If your installer has not done this before you will be funding his research project. I hope he is really, really talented before you undertake this journey. What is your budget for this installation cost?
2- Does the installer have access to break the software code(s) and avoid moving over the E46 EWS, ignition key, etc.

Lastly: Your stock diff will be fine if you don't frequent the drag strip.
 
Regarding installing the M3 engine in a coupe:
@Gransin is bringing up some very good points.
Here are the two big real hurdles you must overcome with this conversion: 1- The stock M30 motor sits at a 20 degree angle the S54 sits at a 30 degree angle. You have two choices, keep the S54 at 20 and destroy your oil pick up location or do it correctly and move the block to 30 degrees. This pretty much tosses out your 6 spd as it would be in a grotesque position in your new and very motor home wide drive tunnel you will have to fabricate. To say nothing of the Frankstein shift linkage you would have to fabricate. You could do a Getrag 265 5 spd but then you'd have to build a custom bell housing that 'clocks' the getrag 10 degrees. This is some serious engineering. If your installer has not done this before you will be funding his research project. I hope he is really, really talented before you undertake this journey. What is your budget for this installation cost?
2- Does the installer have access to break the software code(s) and avoid moving over the E46 EWS, ignition key, etc.

Lastly: Your stock diff will be fine if you don't frequent the drag strip.
Hello,
thank you so much that you are sharing you knowledge with me look like it is very bad idea the thing is base on what you are saying he would destroy my E9 and I had to spend money for his unreasonable project like you said I think installer wants to learn to see if it is possible to convert it to M3 or not and I will be the one funding his research project, I better stay away and rebuild my original engine and be over with.
thank you again you save 50K for me I am glad that we have a member like you and may I ask you how did you learn all of this is there any class for it or just research
Best regards
 
Here is also @JohnFBD 's S54 swapped e9 build thread:

Discussion regarding the S54 swap:

I'd stay with the M30 if you're not totally sure about what you're getting into, it's doable but it's lots of work to get it all buttoned up and working as it should.
 
Lotta work if you aren't familiar with doing a fully built restomod. If you're the type that want's to drop the car off and be called when it's done, just go in with your eyes wide-open. There are LOT's of details that need to be considered not to mention costly with a capital C. If you want to do it, have access to the people that can do it and have the time to wait and the money to spend, go for it!
 
again not a word about suspension /steering. Yes, @Gransin mentions a rack&pinion.... that is possible as race cars do... with mounting the fire wall some inches further back.
So what do you do with 333 HP in a oem E9 setup ? crazy i think. If you want that , buy a M3. Or a M3 with a E9 body on it :D
 
again not a word about suspension /steering. Yes, @Gransin mentions a rack&pinion.... that is possible as race cars do... with mounting the fire wall some inches further back.
So what do you do with 333 HP in a oem E9 setup ? crazy i think. If you want that , buy a M3. Or a M3 with a E9 body on it :D
Hello, it is funny, but you are right it is crazy when you think about it but anyway thank you for sharing your knowledge
 
Lotta work if you aren't familiar with doing a fully built restomod. If you're the type that want's to drop the car off and be called when it's done, just go in with your eyes wide-open. There are LOT's of details that need to be considered not to mention costly with a capital C. If you want to do it, have access to the people that can do it and have the time to wait and the money to spend, go for it!
Hello,
yes I am kind of guy that I like to pay and get it ready what I want but I guess this is not my thing he will destroy my E9
 
As I’m currently doing a M62 V8 swap in e9 Chassis, I can only say electronics (wiring and coding) is by far no problem. There are even DIYs for this, thanks to the e30 community. As example, a standalone management on original ECU is very easy doable (I have already programmed some of these)

But the real advantage, that give me countless sleepless nights are things like: calculate Steering geometries for R&P that the car drives like a nice restomod on the road (without moving firewall and that it’s not driving like a lawnmower), fitting the whole modern drivetrain or at least engine+gearbox into this very very small chassis in terms of space for engine, gearbox etc., fitting different parts like a e28 rearaxle and redesign whole rear suspension to accept a coilover system in the rear, strengthen the chassis to accept&handle the new level of torque and so on…

To transplant a modern engines to a E9 and let a shop carry out this work…I don’t know what is harder. To find a shop that is able to carry out this work (and engineering) or to collect all that money they charge you. If I remember right, the s54 converted E9 from FBDJohn was for sale for like 200-300k$?
 
Last edited:
As I’m currently doing a M62 V8 swap in e9 Chassis, I can only say electronics (wiring and coding) is by far no problem. There are even DIYs for this, thanks to the e30 community. As example, a standalone management on original ECU is very easy doable (I have already programmed some of these)

But the real advantage, that give me countless sleepless nights are things like: calculate Steering geometries for R&P that the car drives like a nice restomod on the road (without moving firewall and that it’s not driving like a lawnmower), fitting the whole modern drivetrain or at least engine+gearbox into this very very small chassis in terms of space for engine, gearbox etc., fitting different parts like a e28 rearaxle and redesign whole rear suspension to accept a coilover system in the rear, strengthen the chassis to accept&handle the new level of torque and so on…

To transplant a modern engines to a E9 and let a shop carry out this work…I don’t know what is harder. To find a shop that is able to carry out this work (and engineering) or to collect all that money they charge you. If I remember right, the s54 converted E9 from FBDJohn was for sale for like 200-300k$?
Thank you so much that you share your knowledge with me I thing no one will spend that kind of time to give you a car with right design and installation and I do not have a knowledge to know what hasn't been fixed like I had a ford cobra years ago with that kind of problem all I knew the car wasn't driving right but I didn't know what was wrong with it I end up selling the car very cheap I will stop doing this project and I will go with original engine I have to learn it is not the money will do the work I have to have a knowledge for that kind of project or pay top dollar and buy the ready one am I right?
god bless you and please stay around since we need the guy like you in here
 
Back
Top