325_driver 422 Report post Posted April 30, 2021 (edited) So the n46 is a tad smokey, no surprise so it got me thinking in the e91 i'm debating swapping a 325i motor into the 320i since i have all the required components available through someone wrecking one near me Anyone gone through this process before? Edited April 30, 2021 by 325_driver Quote Share this post Link to post Share on other sites
M M 250 Report post Posted April 30, 2021 I doubt anyone would notice, I would just put it in and not tell anyone. 1 1 Quote Share this post Link to post Share on other sites
KwS 2429 Report post Posted April 30, 2021 14 minutes ago, M M said: I doubt anyone would notice, I would just put it in and not tell anyone. Thats really bad advice. Not only should the car fail a WOF, and could be stickered by the Police, but your insurance will be void. The process isnt too hard, especially if its all bolt in OEM gear. You'd need to check with a certifier if you need a driveshaft hoop or no, otherwise make sure the rest of the car is up to scratch too (good brakes, since it will have to undergo a brake fade test). 1 Quote Share this post Link to post Share on other sites
325_driver 422 Report post Posted April 30, 2021 6 minutes ago, KwS said: Thats really bad advice. Not only should the car fail a WOF, and could be stickered by the Police, but your insurance will be void. The process isnt too hard, especially if its all bolt in OEM gear. You'd need to check with a certifier if you need a driveshaft hoop or no, otherwise make sure the rest of the car is up to scratch too (good brakes, since it will have to undergo a brake fade test). haha ^ I think there was sarcasm in his comment =D well it seemed it I think it's worth doing the swap to be honest the more i think about it i think the n46 tarnishes such a great car 1 Quote Share this post Link to post Share on other sites
KwS 2429 Report post Posted April 30, 2021 You wouldnt go the whole hog and just M54B30 it? If you're going to all that effort i'd go for the biggest improvement you can Quote Share this post Link to post Share on other sites
325_driver 422 Report post Posted April 30, 2021 4 minutes ago, KwS said: You wouldnt go the whole hog and just M54B30 it? If you're going to all that effort i'd go for the biggest improvement you can at the moment the decision i was weight up is because i have a set of matching CAS DME box, long block etc for a decent price. Wish i was going to 330i but that kind of changes the budget substantially haha if i was going full hog, it's 335i, but it would be better off just buying one of them haha Quote Share this post Link to post Share on other sites
nick496 269 Report post Posted April 30, 2021 Granted, it's a little different. But did it in the E30. As MM says, unlikely to be picked up by anyone who doesn't know what they're looking for. It says BMW on the engine cover still. But I'm done it the right way, to avoid any potential legal issues, which is as KwS says: 34 minutes ago, KwS said: Thats really bad advice. Not only should the car fail a WOF, and could be stickered by the Police, but your insurance will be void. The process isnt too hard, especially if its all bolt in OEM gear. You'd need to check with a certifier if you need a driveshaft hoop or no, otherwise make sure the rest of the car is up to scratch too (good brakes, since it will have to undergo a brake fade test). Providing you can use the driveshaft etc out of the donor, shouldn't be too much of a hassle to get it all certed. Quote Share this post Link to post Share on other sites
Sammo 2550 Report post Posted April 30, 2021 Driveshaft Hoops needed when an engine swap results in 'significantly' more power - indicated at 50%. https://www.lvvta.org.nz/documents/infosheets/LVVTA_Info_07-2016_Drive-shaft_Safety-loop_Requirements.pdf No fun at all, especially if you have a two piece shaft (two hoops) - had to do this in my E46 for the manual conversion cert process and cost me a fair few pingers. Couldn't find the literature but I thought an engine swap with 20% plus more power requires certification, regardless. Was going to say N52B30 all the way but then I saw how piss weak the 320i is - an N52B25 should be a big improvement and just under that 50% mark. I ensured all my modifications were LVVTA certified and declared to my insurer - not worried about WOFs so much as insurance. Lot of people rolling around in $$$$ cars with uncerted coilovers - basically handing the insurer a get out of jail free card. 1 Quote Share this post Link to post Share on other sites
nick496 269 Report post Posted April 30, 2021 Yeah, you're right Sammo, I recall there being discussions about such a swap given the chassis also had the same engine from factory, so might not require hoops. But couldn't find anything to back that up. I'd say expect to put them in, but chat to your certifier about it. Quote Share this post Link to post Share on other sites
Kodachrome 158 Report post Posted May 9, 2021 (edited) How is the 50% increase calculated? Paper specs? Crank or whhels? I'm going from a M30B25 to M54B30, 150 to 234hp, at the crank.. In theory. Edited May 9, 2021 by Kodachrome Quote Share this post Link to post Share on other sites
gofaster 101 Report post Posted May 9, 2021 (edited) I'm booked for the Cert process for my N54 powered 130i in a couple of weeks. Will update After a discussion on a FB Low volume vehicle cert page, adding the turbochargers may warrant driveshaft hoops unfortunately. Edited May 10, 2021 by gofaster Updated info Quote Share this post Link to post Share on other sites
Bandit 194 Report post Posted May 9, 2021 10 hours ago, Kodachrome said: How is the 50% increase calculated? Paper specs? Crank or whhels? I'm going from a M30B25 to M54B30, 150 to 234hp, at the crank.. In theory. 50% is 50%. 2 Quote Share this post Link to post Share on other sites
Allanw 1072 Report post Posted May 10, 2021 I'm pretty sure that ANY capacity increase requires a cert anyway - regardless of power output. Quote Share this post Link to post Share on other sites
Kodachrome 158 Report post Posted May 10, 2021 (edited) On 5/10/2021 at 9:42 AM, Bandit said: 50% is 50%. Lol, sure, but whats measured? My old M30 prob didnt do 150hp. The new M54 might do 235hp (actually spec is 228hp in us). But those things could also be inverted, the new M54 without its intake ("hot" air intake in the E28) might do less and that M30 might have been singing along at like 165hp... which would mean the increase is not 50%, its definitely less. So IMO the only way this system could work is off measured values, not (unclear) paper specs. I've got an American tune on my M54 ECU (I do!), lets just quote crap USA spec detuned 88 octane, Cali-Smog restricted map then, so its definitely not 50%?? I suspect this system was put in place for people putting modern V8s into old muscle cars and going from 180hp to 400. Not people upgrading family lines in BMWs. Quote I'm pretty sure that ANY capacity increase requires a cert anyway - regardless of power output. Yeah but my question was about driveshaft hoops, which are specifically only required on a 50%+ increase. Which my change is within +/- 5% of. Edited May 11, 2021 by Kodachrome Quote Share this post Link to post Share on other sites
325_driver 422 Report post Posted May 10, 2021 9 hours ago, Allanw said: I'm pretty sure that ANY capacity increase requires a cert anyway - regardless of power output. Seems that way * copied from https://www.lvvta.org.nz/documents/suplementary_information/LVVTA_LVV_Cert_Threshold.pdf when compared with the OE engine, the replacement engine: is of the same or less cubic capacity; and has equal or less weight; and uses the same fuel (petrol, diesel, LPG, CNG); and uses the same unmodified attachment points and system (i.e. bolts-in); and uses the same family of block and cylinder head from the same vehicle manufacturer; and the block has the same number of cylinders arranged in the same configuration; and the cylinder head(s) has the same number of valves and camshafts; and the total power or torque increase, including any minor modifications, is no more than 20% over the OE engine specification Quote Share this post Link to post Share on other sites
KwS 2429 Report post Posted May 10, 2021 Also note change in block/head family (M30 - M54), and change in number of cams/valves requires cert. Quote Share this post Link to post Share on other sites