NVADER 54 Report post Posted January 30, 2015 I have a 96 750iL with a very average body and interior and have been offered a good condition, late model, short wheel base 728I. Would be very nice if I could grab it and swap my engine and running gear into the 728. Just wondering what the differences are in terms of engine mounting locations, suspension, transmission tunnel size etc. I'm assuming the engine bay is the same size so setting the engine mounts up can't be too difficult but the v12 tranny must be significantly bigger...has anyone done a similar swap that could shed some light on this? Quote Share this post Link to post Share on other sites
kiwi535 538 Report post Posted January 30, 2015 i would say,from a completely theoretical view point that it must be able to be done.All the 7 series bodies will be the same.If a swb had the V12 then yours will.You will need to swap just about everything over,driveshaft lengths is the only obvious stumbling block to me... Quote Share this post Link to post Share on other sites
aja540i 1906 Report post Posted January 30, 2015 I dont know a lot about the e38, but if its similar to e39 then the 6 cylinder will be quite different to the v8/12 models, possibly have to swap the whole front subframe, steering, suspension, brakes, etc. Plus it will need certing, so you want to use all factory parts if you can! Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted January 30, 2015 all can be swapped if you have both cars , just use the bmw parts websites like bmwfan.net.info cross reference each part http://bmwfans.info/parts-catalog Quote Share this post Link to post Share on other sites
Allanw 1071 Report post Posted January 30, 2015 Big job! May as well supercharge it and do a manaul conversion too Quote Share this post Link to post Share on other sites
allan 295 Report post Posted January 31, 2015 Can the front section of a e38 be removed like a e46? If so and the front sub frame is the same just swap the whole front suspension motor package over. Their is going to be some things i know that will need to be changed for sure it is a BMW after all haha. Quote Share this post Link to post Share on other sites
kiwi328i 118 Report post Posted February 15, 2015 What a mission. You would want to take everything off the front of the V12, everything north of the firewall and the transmission and throw it under the 728i. Work out what you have left. I am guessing the steering is different as well. It will be a load of work and you would want a large garage, under cover at least, because you are going to have lots and lots of parts hanging around. label everything and have containers for everything. Exhausts will be different obviously, but your front suspension will have to swap over as well. You would have to ask yourself if it really is worth it? Certification...and to think you will only have what you had in the beginning, a V12 E38, less than standard,. You may be going upwards from a 728i, but you are going backwards from a std 750i, to a 728i with a V12? That's how I would look at it. I would rather spend the money doing the body on your 750iL. It is supposed to be that length. Quote Share this post Link to post Share on other sites
NVADER 54 Report post Posted February 15, 2015 BMW did make a swb e38 750 but to my knowledge it was only sold in Europe so it would be cool to replicate it. Pretty soon I'll have the space to do a long term project but i don't have the will or the skill to be cutting into transmission tunnels/firewalls etc. You're probably right if i was charging myself for the time it would take to swap everything over but i wouldn't be. On the other hand, i can't paint or certify rust repairs so all of that would be a cost, then there's the reasonably shabby mid 90's interior that all needs replacing/fixing up, whereas the 728s is mint. But i appreciate the input. Was just an option that was put in front of me so thought I'd explore the option a bit Quote Share this post Link to post Share on other sites
kiwi328i 118 Report post Posted February 15, 2015 You can still make the most of that donor 728i. Move all the better stuff over, but tbh the 750il, stuff you would think is better? At the end of the day, your biggest calling card is the V12, that is the thing you have to secure. For a lot heartache, going to a swb version is not worth it I don't think. You can move all the better interior over from the 728i and you are half way there. But heck go for it, if you want to, mucking around with cars isn't always supported rationally. Having a LWB V12 probably isn't that rational anyway, so what the hey? Sometimes doing stuff with our cars, is because you want to, because you see the justification, and that's all that matters. Cheers 2 Quote Share this post Link to post Share on other sites
kulgan 1042 Report post Posted February 18, 2015 You can still make the most of that donor 728i. Move all the better stuff over, but tbh the 750il, stuff you would think is better? At the end of the day, your biggest calling card is the V12, that is the thing you have to secure. For a lot heartache, going to a swb version is not worth it I don't think. You can move all the better interior over from the 728i and you are half way there. But heck go for it, if you want to, mucking around with cars isn't always supported rationally. Having a LWB V12 probably isn't that rational anyway, so what the hey? Sometimes doing stuff with our cars, is because you want to, because you see the justification, and that's all that matters. Cheers What a mission. You would want to take everything off the front of the V12, everything north of the firewall and the transmission and throw it under the 728i. Work out what you have left. I am guessing the steering is different as well. It will be a load of work and you would want a large garage, under cover at least, because you are going to have lots and lots of parts hanging around. label everything and have containers for everything. Exhausts will be different obviously, but your front suspension will have to swap over as well. You would have to ask yourself if it really is worth it? Certification...and to think you will only have what you had in the beginning, a V12 E38, less than standard,. You may be going upwards from a 728i, but you are going backwards from a std 750i, to a 728i with a V12? That's how I would look at it. I would rather spend the money doing the body on your 750iL. It is supposed to be that length. It's no bigger job than any engine conversion. And it's one I plan on doing to my 740i when I find a decent 750il donor car. There are many reasons why a person might want to do this swap. Since getting a E38 my dream car has been the E38 750i. I personally think the shortie is a better looking car than the il and would handles the corners a lot better than the long wheelbase. And you cant get one in NZ. Yes, you have to swap the suspension, diff, transmission and engine but the good part is that all the mounting points are the same. Drive shavt will have to be shortened. The only issue will be electronics and wiring. The easiest option would be a aftermarket ECU. Something like MegaSuirt. Not original but a lot easier than putting two Original ECU's and DME's into the car. Eventually I'd like to do a Dinan twin turbo replica with a 6 speed manual. Ok, the V12 conversion is a serious possibillity. The twin turbo 6 speed is a dream. lol Quote Share this post Link to post Share on other sites
kiwi328i 118 Report post Posted February 19, 2015 It's no bigger job than any engine conversion. And it's one I plan on doing to my 740i when I find a decent 750il donor car. There are many reasons why a person might want to do this swap. Since getting a E38 my dream car has been the E38 750i. I personally think the shortie is a better looking car than the il and would handles the corners a lot better than the long wheelbase. And you cant get one in NZ. Yes, you have to swap the suspension, diff, transmission and engine but the good part is that all the mounting points are the same. Drive shavt will have to be shortened. The only issue will be electronics and wiring. The easiest option would be a aftermarket ECU. Something like MegaSuirt. Not original but a lot easier than putting two Original ECU's and DME's into the car. Eventually I'd like to do a Dinan twin turbo replica with a 6 speed manual. Ok, the V12 conversion is a serious possibillity. The twin turbo 6 speed is a dream. lol Would be nice to see that happen. It would be one of the more impressive projects if it came to light. Nothing quite like a really nice E38. Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted February 22, 2015 If a couple of members here can get the v12 in their E34s, im sure it cant be that much harder to drop it into the E38 SWB. iirc they all use the same steering, unlike the e39 that used rack and pinion on the sixes, so fitting the v12 setup shouldnt be too hard. a SWB 750i would be lush. The LWB is just too much car for around town here, the SWB is just much more manageable. 1 Quote Share this post Link to post Share on other sites
_ethrty-Andy_ 2132 Report post Posted February 23, 2015 My E38 is longer than my Hiace, and its just the SWB. I struggle fitting the hiace into holes some times LWB is madness if you work and/or play in a city 1 Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted February 23, 2015 I found the 750iL that had a while back with front and rear PDC was ok to park etc , nice easy steering and good visibility and beepings from the PDC etc but yes some parking spaces where just too small Quote Share this post Link to post Share on other sites
Michael. 2313 Report post Posted February 24, 2015 Considering 95% of this would be a bolt on and swap over job it's pretty easy. Quite a fun process if time and funds allow. Quote Share this post Link to post Share on other sites
Allanw 1071 Report post Posted February 25, 2015 Considering 95% of this would be a bolt on and swap over job it's pretty easy. Quite a fun process if time and the Mrs allows. fixed. 1 Quote Share this post Link to post Share on other sites
Michael. 2313 Report post Posted February 25, 2015 Hahaha touche 1 Quote Share this post Link to post Share on other sites
