[Boundless46]

I've been looking around for info on B48's with Big Turbo's but I haven't gotten much. PureTurbo's rates their turbo good for 350whp but I haven't found anyone running it. Ive seen a BigBoostTurbo post of a 420i on their kit getting 422whp 487tq. I have a 330i so I'm guessing I would get more power out of it.
Is anyone running a Big Turbo on their B48?
Power Output?
Problems faced throughout the process?
Anything helps!

[RMMAGA]

The stock turbo is good for 23-24 psi. If your not running more then that you will see no difference in power based on my experience

also will need to have good fuel, like e20 or better to take advantage of a larger turbo and run high boost like 25-26psi without issues with poor timing, I have run up to 26psi on my Taiwanese hybrid, but not really confidant to go higher then that on stock engine internals, I try to only make peak psi at 6000-7000 rpm to try to be easier on the rods and pistons, 3000-4000 for example I only run 21-23 psi, then taper it up to 25-26 by 6000

[Boundless46]

Originally Posted by RMMAGA

The stock turbo is good for 23-24 psi. If your not running more then that you will see no difference in power based on my experience

also will need to have good fuel, like e20 or better to take advantage of a larger turbo and run high boost like 25-26psi without issues with poor timing, I have run up to 26psi on my Taiwanese hybrid, but not really confidant to go higher then that on stock engine internals, I try to only make peak psi at 6000-7000 rpm to try to be easier on the rods and pistons, 3000-4000 for example I only run 21-23 psi, then taper it up to 25-26 by 6000

Do you know your power output?? I'm currently BM3 Stage 1 E30 all stock and came out to 250whp/320tq on a 95° day. I want to go Stage 2 but if I get a BigBoost turbo kit, they supply me with a custom downpipe and charge pipe so kind of pointless if I buy them now. I just want the most power out of my car but safely and not blowing up the intake manifold like couple B58 guys did

[RMMAGA]

no access to dyno here so I normally look at VD based on my logs on the same road sections for tuning using 3rd pulls, it is hot here DA is about >2200ft

the way I tuned it is so that I am running load limit form 3000-5500rpm, then hits boost limit at about 5500 to 7000, boost limit is set to 27 psi, load limit to 220-225, but normally you want it to tune the WGDC table to end up about 1-2 psi below the target which is why it normally runs about 25-26 psi even with a 27psi target.

also I recently loaded back the stock tune for fun to see A B with stock, and see how accurate VD is as well as the delta form stock, it looks bang on, about 170wph, car was rated 185 crank, so that feels about right as normally they are a bit underrated and with 10-12% drive train loss it seems correct

I also did a 12.65 quarter and 4.49 0-60 (4.22 1ft), that lines up pretty good with about 330-340wph

I think the intercooler is pretty strong (I think) I have seem boost spikes especially on gear changes up to 32 psi on mine and no issues yet

[Avaley]

I'd be worried about pushing past 350whp and the internals as they are not forged.

RMMAGA clearly has pushed his to 27 PSI but there is no way a B48 doesn't crack a piston head of bend a crankshaft at 30 PSI with big turbos.

The B48 has higher tuning potential than a N20 for sure, but no one has long-termed a big turbo B48 based on my knowledge but definitely pushing C45 territory.

[Avaley]

Originally Posted by Boundless46

I've been looking around for info on B48's with Big Turbo's but I haven't gotten much. PureTurbo's rates their turbo good for 350whp but I haven't found anyone running it. Ive seen a BigBoostTurbo post of a 420i on their kit getting 422whp 487tq. I have a 330i so I'm guessing I would get more power out of it.
Is anyone running a Big Turbo on their B48?
Power Output?
Problems faced throughout the process?
Anything helps!

I would stage 2 first with a catless downpipe, intake and high end exhaust first if I were you. I like AWE for high end quality and still great value. Best to play with the exhaust and intake before the turbos imo.

I see you are based in cali so there are emissions issues, but if you could delete the secondary resonator in the midpipe as well for a straight pipe.

I have mine in the shop now for a full stage 2 FBO build without a big turbo and based on the tuner and speaking with manufacturers, it should do 350 at the crank and 370 torque at the crank. Should be doing a mid 12s quarter mile and 4.5s 0-60.

This is just a hair faster than a B58 engine, but the next step would be big turbo, methanol, race camshafts, E50, nitrous, etc but imo at a certain point, you are better off buying a M340i / M440i or a Supra.

[Avaley]

Originally Posted by Boundless46

Do you know your power output?? I'm currently BM3 Stage 1 E30 all stock and came out to 250whp/320tq on a 95° day. I want to go Stage 2 but if I get a BigBoost turbo kit, they supply me with a custom downpipe and charge pipe so kind of pointless if I buy them now. I just want the most power out of my car but safely and not blowing up the intake manifold like couple B58 guys did

Just saw they are supplying everything, have you asked them about stock internals on the B48 running high boost?

Safest to buy forged internals kit but also could find a custom tuner to dial up the boost on the dyno with a big turbo, bet someone like CaryTheLabelGuy could build you a damn safe tune that does 400+ whp at a manageable PSI.

[Boundless46]

Originally Posted by Avaley

Just saw they are supplying everything, have you asked them about stock internals on the B48 running high boost?

Safest to buy forged internals kit but also could find a custom tuner to dial up the boost on the dyno with a big turbo, bet someone like CaryTheLabelGuy could build you a damn safe tune that does 400+ whp at a manageable PSI.

I have contacted BigBoost yet, I wanted to know if anyone was running it and do more research before I do. Upgrading to forged pistons and a big turbo would be a good ticket, but reliability would be key.
My main goal is to get low 7's 1/8th Mile.
My best run so far was 8.599 on all season tires with BM3 Stage 1. I will be getting better tires in the future. I do notice a lot of heat soak on my car, so would an Interchiller be my Best Buy? I've read that Pure has done it on an S55 and was going to do it on a B58 but I'm not sure if they did. Sub-Ambient temps sounds good

[Boundless46]

Originally Posted by Avaley

I would stage 2 first with a catless downpipe, intake and high end exhaust first if I were you. I like AWE for high end quality and still great value. Best to play with the exhaust and intake before the turbos imo.

I see you are based in cali so there are emissions issues, but if you could delete the secondary resonator in the midpipe as well for a straight pipe.

I have mine in the shop now for a full stage 2 FBO build without a big turbo and based on the tuner and speaking with manufacturers, it should do 350 at the crank and 370 torque at the crank. Should be doing a mid 12s quarter mile and 4.5s 0-60.

This is just a hair faster than a B58 engine, but the next step would be big turbo, methanol, race camshafts, E50, nitrous, etc but imo at a certain point, you are better off buying a M340i / M440i or a Supra.

On BM3 Stage 1 E30 Stock I got 253whp/314tq with like 95° ambient temp. I'm sure with Stage 2, catless downpipe & drop in filter a B48 will crack 320whp & close to 400tq. You got an Instagram I can follow the build?
Mine is @Boundless.F30

[Avaley]

Originally Posted by Boundless46

I have contacted BigBoost yet, I wanted to know if anyone was running it and do more research before I do. Upgrading to forged pistons and a big turbo would be a good ticket, but reliability would be key.
My main goal is to get low 7's 1/8th Mile.
My best run so far was 8.599 on all season tires with BM3 Stage 1. I will be getting better tires in the future. I do notice a lot of heat soak on my car, so would an Interchiller be my Best Buy? I've read that Pure has done it on an S55 and was going to do it on a B58 but I'm not sure if they did. Sub-Ambient temps sounds good

I think the B series has gone to heat exchangers. I haven’t had any issues with heat soak but have looked into the CSF heat exchanger which shows much lower temps based on their testing. The CSF works for both B58 and B48. Wagner makes one as well. IAT temps look much lower with the CSF but the 2.0L doesn’t have the heat of the B58 given the spacing in the engine bay and just less displacement. N55s had bad heat soak when tuned and big turbos but some of the issues were resolved by going to air to water.

I’ll follow you but I’m planning to post all my build info on this forum which should be soon

[Avaley]

Originally Posted by Boundless46

On BM3 Stage 1 E30 Stock I got 253whp/314tq with like 95° ambient temp. I'm sure with Stage 2, catless downpipe & drop in filter a B48 will crack 320whp & close to 400tq. You got an Instagram I can follow the build?
Mine is @Boundless.F30

Incase you hadn't seen:

This is Dronamashina 's car stage 2 e50 stock turbos.

[Avaley]

Originally Posted by Boundless46

I have contacted BigBoost yet, I wanted to know if anyone was running it and do more research before I do. Upgrading to forged pistons and a big turbo would be a good ticket, but reliability would be key.
My main goal is to get low 7's 1/8th Mile.
My best run so far was 8.599 on all season tires with BM3 Stage 1. I will be getting better tires in the future. I do notice a lot of heat soak on my car, so would an Interchiller be my Best Buy? I've read that Pure has done it on an S55 and was going to do it on a B58 but I'm not sure if they did. Sub-Ambient temps sounds good

Also do you have 6MT or 8AT? Either way, I highly recommend xHP transmission flash tune, you can scale up your torque for launches and definitely shifts faster.

Tires are so key. I have stock runflats and i think Michelin PS4S on the M4 rims of another aftermarket rim 225/45/19 front 245/45/19 rear as a performance wider tire is necessary at stage 2.

While stage 1 i was already feeling the weakness of the runflats in launches especially around corners. Even going to a non runflat would be an improvement but if you are in cali, no excuse not to have a Ps4s on!

[RMMAGA]

I am also debating to build the engine, I am just not sure how easy it is, I got quoted about 3500 USD, for pistons and rods.

I am worried about the shop messing it up, the plasma coated cylinder walls needs some special attention to how they hone it, also I am not sure if they would need to balance the crank or not, not sure the shops here can do that well, does anyone know the common cylinders and rod like carillo for example, are they same weights as stock parts so should not need any crack balancing?

FYI there is no magic about the tune, I learned it when the lockdowns started and I was bored, at similar timing and AFR and boost and environmental conditions you will have similar power, so it not like some tuner can get you more or less power, a competent tuner should be able to give you what for your goals and your risk tolerance

it does look like B48 has a lot of potential, we do not seem to have any fueling issues as we have same fuel system as B58, my fueling data looks rock solid even running 27psi at high rpm, with my meth turned off, and I run like 12.2 AFR

also for the intercooler rad it seems more then capable, the difference in my IAT with meth on or off is only a few degrees, it almost like the low temp radiator is the same one as the one used on the B58....and yup it is

[SRHosein]

Originally Posted by RMMAGA

I am also debating to build the engine, I am just not sure how easy it is, I got quoted about 3500 USD, for pistons and rods.

I am worried about the shop messing it up, the plasma coated cylinder walls needs some special attention to how they hone it, also I am not sure if they would need to balance the crank or not, not sure the shops here can do that well, does anyone know the common cylinders and rod like carillo for example, are they same weights as stock parts so should not need any crack balancing?

FYI there is no magic about the tune, I learned it when the lockdowns started and I was bored, at similar timing and AFR and boost and environmental conditions you will have similar power, so it not like some tuner can get you more or less power, a competent tuner should be able to give you what for your goals and your risk tolerance

it does look like B48 has a lot of potential, we do not seem to have any fueling issues as we have same fuel system as B58, my fueling data looks rock solid even running 27psi at high rpm, with my meth turned off, and I run like 12.2 AFR

also for the intercooler rad it seems more then capable, the difference in my IAT with meth on or off is only a few degrees, it almost like the low temp radiator is the same one as the one used on the B58....and yup it is

I was looking at engine rebuild. Based on B58, most people are just doing pistons and rods. I believe B48 should be the same. I was looking at CP/Mahle/Supertech for pistons rods ect. See attached for an idea of the cost - CP and Supertech. Could not find Mahle pistons with 11:1 compression ratio. I may eventually do turbo and test limits. Most failures I am aware off are pistons. I have not heard of any other issues.

I may do turbo upgrade later this year and update you all.

[Boundless46]

Originally Posted by SRHosein

I was looking at engine rebuild. Based on B58, most people are just doing pistons and rods. I believe B48 should be the same. I was looking at CP/Mahle/Supertech for pistons rods ect. See attached for an idea of the cost - CP and Supertech. Could not find Mahle pistons with 11:1 compression ratio. I may eventually do turbo and test limits. Most failures I am aware off are pistons. I have not heard of any other issues.

I may do turbo upgrade later this year and update you all.

I'm glad someone is trying to push this motor to the Max! Definitely going to be pretty quick. Do you plan on taking it to a shop or trying to do it yourself? I feel like all that work would be a pretty penny.
I was thinking of bigger turbo upgrade but now y'all got me thinking of strengthening my motor.

[Avaley]

Originally Posted by Boundless46

I'm glad someone is trying to push this motor to the Max! Definitely going to be pretty quick. Do you plan on taking it to a shop or trying to do it yourself? I feel like all that work would be a pretty penny.
I was thinking of bigger turbo upgrade but now y'all got me thinking of strengthening my motor.

The big turbo will cost about the same as full parts + install for a stage 2 FBO.

I bought this equivalent for my 430i, plus an Injen air intake and an AWE exhaust all from Mike @ x-ph. https://x-ph.com/bootmod3-downpipe-c...48-combo-deal/

I suggest first going stage 2 FBO as those will mainly help your exhaust flow and improve air intake capability, likely won't require any internal upgrades and be the largest performance gain per dollar. Stage 2 FBO will probably cost something like $3,500 plus install. These bolt ons are ones you would do anyways if you were planning on going big-turbo IMHO as stock downpipe with cats, cat in midpipe will bottleneck a big turbo.

A big turbo would be the next step but based on my research 350bhp and 370btq is doable on the B48 without a bigger turbo and custom internals. If you want to push past 400 thats when the big turbo kit and forged internals comes in, but for me the cost benefit of big turbo isn't worth it as the total cost of the car at that point would exceed buying a 3.0L ($6500) without the M performance parts, as the 6 cylinder has even more tuning overhead and won't require the same cost to run reliably for the same output.

Basically i think if you can keep the cost of upgrading your car under $5k-ish and get to the stock 440i performance, its worth it otherwise for a new car that is over 50k all in cost, its smarter to either buy a M340i, C43 AMG, etc as at 60k price point those are hard to beat.

[Boundless46]

Originally Posted by Avaley

The big turbo will cost more than just stage 2 FBO.

I bought this equivalent for my 430i, plus an Injen air intake and an AWE exhaust all from Mike @ x-ph.

I suggest first going stage 2 FBO as those will mainly help your exhaust flow and improve air intake capability, likely won't require any internal upgrades and be the largest performance gain per dollar.

A big turbo would be the next step but based on my research 350bhp and 370wtq is doable on the B48 without a bigger turbo and custom internals.

https://x-ph.com/bootmod3-downpipe-c...48-combo-deal/

Yeah I'm definitely getting a chargepipe & downpipe soon as I already have BM3. I have been waiting on it since BigBoost kit comes with custom chargepipe and downpipe. 370tq is doable, I'm only 50lb away from it and I'm fairly stock. I'm just trying to think ahead and after Stage 2, I will be wanting more power
PureTurbo's is based like 10 minutes away from me lol so I will probably head down and see if they have any actual dyno graphs or any data on their product.
I understand I can always get a B58, but I got my car for $16k couple months back (coronavirus deals) and It would kind of be more money to trade in for a 340i that are going for $30k at the moment.

[Avaley]

Originally Posted by Boundless46

Yeah I'm definitely getting a chargepipe & downpipe soon as I already have BM3. I have been waiting on it since BigBoost kit comes with custom chargepipe and downpipe. 370tq is doable, I'm only 50lb away from it and I'm fairly stock. I'm just trying to think ahead and after Stage 2, I will be wanting more power
PureTurbo's is based like 10 minutes away from me lol so I will probably head down and see if they have any actual dyno graphs or any data on their product.

oh awesome, if you are that close to them I definitely suggest going in and building a strong relationship with them as they are WAY smarter than internet randos

[Avaley]

Originally Posted by Boundless46

Yeah I'm definitely getting a chargepipe & downpipe soon as I already have BM3. I have been waiting on it since BigBoost kit comes with custom chargepipe and downpipe. 370tq is doable, I'm only 50lb away from it and I'm fairly stock. I'm just trying to think ahead and after Stage 2, I will be wanting more power
PureTurbo's is based like 10 minutes away from me lol so I will probably head down and see if they have any actual dyno graphs or any data on their product.
I understand I can always get a B58, but I got my car for $16k couple months back (coronavirus deals) and It would kind of be more money to trade in for a 340i that are going for $30k at the moment.

crazy deal...I felt good about getting a good deal at the time and I paid about 46k before taxes title and fees for a brand new 430i xDrive, premium package, cold weather, + some other extras in 2017...this was the first car i bought

I would also avoid a 340i as the M340i one year later has notable upgrades, though those will be going for like-new prices at best but i'm still shocked you got basically my same car for that price...

[Avaley]

As an additional heads up, i see you are based in California so you will need a B46 downpipe if your car is US spec.

Make sure when you order you specify this as B46 downpipes as B48 will not fit a US spec 2.0L turbo 4.

[SRHosein]

Originally Posted by Boundless46

I'm glad someone is trying to push this motor to the Max! Definitely going to be pretty quick. Do you plan on taking it to a shop or trying to do it yourself? I feel like all that work would be a pretty penny.
I was thinking of bigger turbo upgrade but now y'all got me thinking of strengthening my motor.

I plan on doing it myself, I rebuilt engines before just not BMW ones.

[SRHosein]

Originally Posted by RMMAGA

The stock turbo is good for 23-24 psi. If your not running more then that you will see no difference in power based on my experience

also will need to have good fuel, like e20 or better to take advantage of a larger turbo and run high boost like 25-26psi without issues with poor timing, I have run up to 26psi on my Taiwanese hybrid, but not really confidant to go higher then that on stock engine internals, I try to only make peak psi at 6000-7000 rpm to try to be easier on the rods and pistons, 3000-4000 for example I only run 21-23 psi, then taper it up to 25-26 by 6000

The Taiwanese hybrid turbo is that similar to Pure turbos?
Or is it just the compressor wheel change to a 11 blade one and everything else on turbo stock?