[Evan(CA)]

I apologize for my noob questions that are likely answered already and I am slowly researching on here more and more each day. However a thread of my own with my specific situation is nice to have.

I have always been a Z32 1990-1996 Nissan 300zx Twin Turbo Guy. I had a non turbo for my first car and literally 10+ in the subsequent almost 20 years now.

Given that, I am VERY familiar with turbo cars and wrenching on them. I have ALWAYS stayed away from the 96 300zx's because of smog. It's an absolute nightmare to find a shop that will let the visual stuff slide despite the actual numbers on the rollers being perfect.

How big of a deal is smog for you guys? I'm in California and boy does it suck for smog and motorsports in general.

I have only just recently started looking into modding this as I have so many toys. A 500whp 93 Z32, a 360whp 91 z32, 2009 Ducati 1098s motorcycle and more projects in between than I can remember. Everything from complete part outs to the uni-body and built all the way back up from there.

I am confident that I can do ANY mechanical work on the car but BMW's seem to "LOCK" their ECU's and force you to go somewhere with an OEM BMW scan tool. How much truth to this is there, especially when you start to mod?

Typically I'd start with standard bolt ons, air intake, full turbo back exhaust, off the shelf ECU tune. Manifolds are changed when the engine is out but downpipes are easily swapped in and removing the precats(1st set of cats) causes no issue in emissions despite having to actually run the car on the rollers at 15 and 25 mph. The main cats do need to be swapped back in for smog but it's quick and easy.

I know the turbo back exhaust has always been a headache for the 96 Z32's with pre and post cat o2 sensors. Do the aftermarket exhausts for the newer cars come with bungs for 02 sensors that negate this problem without throwing codes for the completely open exhaust?

Off the shelf ECU chips are generally thought of as garbage and a real tune on a dyno is the way to go. Are there any BMW specialist's in SoCal who do this?

Without creating noticeable turbo lag how big can you go with the sequential turbos? What's the ideal 1-2 punch? I don't mind it feeling like a turbo car to some degree as you would never know it's a turbo in it's stock form. Are upgraded recirc valves needed for upgraded turbos? Hell I don't even know if it's a MAF or MAP car that's how much I've actually researched modding the BMW as I NEVER thought I would.

However I'm between projects and was looking for a new DD. I was going to sell the BMW but I only paid 7800 for it with 114k and it's SUPER clean with m sport wheels I believe. So I can mod it or sell it for a profit.

Is an upgraded intercooler before upgraded turbos a waste? The cross-feed turbos on the Z32's and sequential set up here make them similar but at the same time apples and oranges to compare.

Are oversized charge and intake piping a thing with these? That's one of the biggest mods you can do on a Z32. Exhaust manifolds, turbos and 3" all the way back with 2.5" intake/charge piping. If you've seen a z32 engine bay that's as big as will possibly fit. They literally picked the engine first and designed the car around it so there is ZERO room to work so engine pulls are something that happens often but after all the proper deletes isn't very hard or time consuming.

I know the engine is fine for the power I want but what about the transmission and drivetrain? If I am going to blow up the autotragic I'll skip the project all together.

Do you use lightweight crank/flywheel/driveshafts at all? Those are other ways to easily free up HP and make the car more peppy with Z32's.

Don't flame me for asking for information I'm sure has been answered 1k times, I'm trying to find it as we speak but I am really just now getting serious about this.

I guess what I'm asking is where do things differ drastically and what are the work arounds, if any? Where do I start and where do I stop? I have no intention of this being my fastest car and don't want to sacrifice TOO MUCH reliability but am well aware that is part of the game.

This all really came about after deciding it's time for a new DD. It comes down to buying a new dual motor Model 3 and selling this for a profit, or modding this for a little (Subjective, I've had 9s cars & still have crotch rockets) more pep. Somewhere in between the 2 Z's 360whp-500whp would be nice. Closer to 500 as it's a big heavy 4 door sedan.

I'm not concerned about suspension, I have other vehicles for canyon carving. I simply want to have some fun while going about my day. A few stop light pulls and the need for just a flick of opposite lock when I want to around a corner. It pretty much does that now but wont pull through the slide if that makes sense.

[StradaRedlands]

I'm NOT an expert in modding, but from hanging out here a while, JB4 is really well liked: https://burgertuning.com/collections...es-n55-bmw-jb4
Charge pipe and a better intercooler are recommended as the factory ones are too small/brittle, so good upgrades regardless. Lots of discussion on downs/cats with lots of opinions. YMMV on that.

xHP is very respected and recommended for transmission flash. https://www.xhpflashtool.com/ That'll make the car feel better regardless of what you do.

Hope that helps point you in the right direction!

[Rickypalmtrees]

I have the MHD tune stage 1 but bought all stages and just waiting on my Intercooler and downpipe to go to stage 2 plus. I love the MHD tune. I already did the charge pipe (VRSF) and tune up and much more maintenance to accompany the mods. But I heard JB4 is a good tune as well. I keep the burbles on soft which is perfect. Good luck buddy!!

[NikMN]

Check e9x turbo section. You will find tons of information there same n55 engine. I had jb4 on my 335 for 3 years without any issues. If I were to do it again I would get mhd.

[jayster0966]

I live in CA myself and have a modded 11 F10 and Bootmod3 is the way to go for me. Even with my setup I just flash back to stock every 2 years and set the monitors to pass smog. Using race catted downpipes rather than catless makes everything alot easier.

[ChiltiCoatl89]

Upgrading all the plastic components that connect from the intake to the turbo and to the intercooler will be a pristine upgrade, and I did heard that upgrading the Intercooler is not at all a bad idea! cost less as well!