MyE28.com

Hey all, I've done a fair amount of lurking around and searching, but haven't quite found the answers to some specific questions I have about turbocharging my '86 535is.

First off, the motor in the car is not the original. When my dad initially bought the car to flip before it was given to me, the motor was shot due to a head gasket leak and serious PO neglect. The entire thing was seized, so another M30 from a 7 Series was put in. We had to fab up a motor mount plate to bridge the gap because it wasn't a direct bolt in to the existing mounts. As well, the oil filter is mounted at an angle and can be accessed from the top as opposed to getting underneath the car. This leads me to believe it's an M30B35, but could I be wrong?

Secondly, I don't have a very big budget for the build, so I'd like to keep the transmission as an auto for now, and am very hesitant to dive into a standalone ECU like MegaSquirt. Could I get 300hp/300tq to the wheels with these limitations in mind? Would I absolutely need an intercooler, or could the engine survive without one? Can the tranny handle that level of power? My budget for everything would be around $6K, knowing full well that projects always go over budget and that I'm trying to keep my goals modest.

I'm trying to make this a fun weekend driver kind of car, so I can afford to keep it off the road while doing the install and any troubleshooting that will arise.

Thank you!

Welcome to the board.

So, you've got a 535is auto, they didn't make those until 87. If your car is a 85 it's not a factory built iS car. B35 swap, that's even better. Change the diff to a 3.91 or 3.73. It'll wake it up quite a bit. The car's pretty lethargic I'm sure. Do you have a reason why you don't want to 5 speed swap it?

Let's start with the basics before a fantasy turbo build. You're wanting 300tq out of a car with about half of that, due to the "antiquing process".

The e28 is a nice ride, but it's not necessarily a 300hp car. The m5 was made with a better suspension/brakes and it felt pretty alright when it was new, another 50hp would feel great in that car. I've seen many people dump 10s of thousands of $ into cars to try to get 300hp. It's not easy or cheap.

There are a lot of other cars that have that much power potential easily. Think 99 camaro/firebird/mustang.

Whats your calling for the e28 to exceed the limits of its platform? The car wasn't built for a lot of torque or hooning.

Not to sound wrong but I'm just trying to write something that will reflect to people thinking that the e28 is just a bigger e30 with gobs of potential (the monster e30s have hundreds of hours of work put into them). It's not in your budget to build a beater e28 with a reliable tuned automatic 300tq for $6k if you have to ask. The transmission will need rebuilt plus the torque converter. There's half your $.

I'm not saying you cant do it. I want to see you fulfill your goals. But to be realistic, there is a lot of work and a almost indefinite amount of time learning to tune the shit. A AFM and begi are not gonna cut it, I don't care what they say. Sure it's awesome for a little while but not when the throttle meets the interstate and you wanna lay it down like the cars meant to be.

I think you'd be surprised what the car feels like with a proper differential and transmission combo. If you wanna go turbo- tune the car with megasquirt so you know what's going on, then make boost.

HTH, I'm just speaking my mind.

Thanks for the welcome, and the honesty.

I'm not necessarily opposed to a manual swap. My intention was to keep it auto to lower the cost of the build, especially since the torque converter was rebuilt a year or so ago back when this was my only vehicle. It was slipping, not shifting, etc. I'd like to get some use out of it before I pull it out, honestly.

I'm also very hesitant to do a standalone ECU as I had mentioned before. Is the performance really that dismal with Motronic? To be frank, reading others talking about MegaSquirt and the like goes above my head. If I can do this without needing to learn how to operate/tune a standalone, I'd like to.

Okay, so my goal with a budget of $6K isn't feasible. What can be done at that price point, and what am I looking to spend approximately to reach my initial goals?

My reasoning for looking at a turbo build is to see where I can take my dream ride to while keeping it (mostly) reliable. I'm not looking to drag race or anything like that. I've got the euro conversion ready to go and am looking into body, paint, and interior as well. I'm making this into my dream car and am curious just where I can take things as far as power goes.

Thanks again for the trouble!