745i turbo transplant in my 535is

[grey ghost]

The wealth of data here is amazing, and scary at the same time.
As I want forced induction, and have a donor car, the more I read the further away I go from actually pulling the trigger and swapping it over.
I know I can do the swap, and having what I need made is not an issue either, but the opinions of those with significant experience tells me NO, Don't DO It. Go with a TCD kit.

My thing is this, I paid near nothing for my 745 with everything on it, and the TCD kit is 5K.

Now trust me when I tell you that I would love to wake up christmas day and have a TCD stage 3 kit under my christmas tree, but thats not going to happen.

Decision decision........

[winfred]

you can look at the possibility to sell off the 745 bits off to less enlightened people to fund a modern build, or...... do the swap and upgrade to better bits and pieces as funds allow, the factory bits are just so primitive by current standards and it really doesn't cost a ton to build a really fast car any more, i think its the golden age of forced induction with so much good stuff available and cheap via the internet you can blow anything

[demetk]

IMO, free is free, and the learning experience is priceless.

[Jsanders]

I bought a 533i with a 745i setup on it. While I realise it's not the bees knees, it is my first turbo setup and I find it a good gateway into the forced induction world.

[George]

IMO, free is free, and the learning experience is priceless.

Except that its not. Call me a perfectionist, call me anal but there is no way I would every throw any of that equipment on without having it rebuilt.

I deal with turbocharged cars everyday as part of my job. I've caused them to fail in quite a few different manners. There is no way I'd put a 30 year old K27 turbo without having the entire unit rebuilt. At the point of the rebuild, you need to ask yourself, why am I not upgrading the compressor to something that was designed in the 2000's and not the 70's?

This begs the question, why am I trying to make power with a 2" inlet to the turbo? which begs the question, why am I using a non-adjustable wastegate. Which begs the questions why am I using the factory ecu and so on and so on.


Its a slippery slope.

[winfred]

thats kinda what i wanted to say i modified a 745 exhaust manifold on my redneck mill and damn that outlet port is tiny, about the size of the exhaust port on the head except 5 more are going through the same hole, serious choke point

IMO, free is free, and the learning experience is priceless.

Except that its not. Call me a perfectionist, call me anal but there is no way I would every throw any of that equipment on without having it rebuilt.

I deal with turbocharged cars everyday as part of my job. I've caused them to fail in quite a few different manners. There is no way I'd put a 30 year old K27 turbo without having the entire unit rebuilt. At the point of the rebuild, you need to ask yourself, why am I not upgrading the compressor to something that was designed in the 2000's and not the 70's?

This begs the question, why am I trying to make power with a 2" inlet to the turbo? which begs the question, why am I using a non-adjustable wastegate. Which begs the questions why am I using the factory ecu and so on and so on.


Its a slippery slope.

[demetk]

This begs the question, why am I trying to make power with a 2" inlet to the turbo? which begs the question, why am I using a non-adjustable wastegate. Which begs the questions why am I using the factory ecu and so on and so on.

For some of us who just want stock turbo pressures, all of the above will work just fine. That extra 60-70 hp feels just great and is all I want at the moment. At that level, you're not stressing the engine so you can run no fuss-no muss reliably for many years. I never had to worry about my 745 all the way up to 300k until I retired it due to rust. The rebuilt turbo had 175k on it.

Also, being able to repurpose usable components is a very worthwhile endeavor in my books.

[demetk]

you can look at the possibility to sell off the 745 bits off to less enlightened people to fund a modern build

grey ghost, send them to me so I can turbo my e23.

[Jeremy]

I never had to worry about my 745 all the way up to 300k until I retired it due to rust. The rebuilt turbo had 175k on it.

Also, being able to repurpose usable components is a very worthwhile endeavor in my books.

Yes, but taking parts from a runner of known condition is a bit different than using parts with unknown history/mileage. I've seen more than a few 745i builds on here that started great, but became a real hassle of replacing parts as they broke in short order after the build.

At the very least, if you're intent on using the 745i parts, send the turbo off for a rebuild with the later compressor wheel. You'll have modest results, but if you have modest expectations it might work out alright in the end. It seems that very few people are satisfied with low/moderate levels of boost though, so consider yourself warned.

Jeremy

[grey ghost]

you can look at the possibility to sell off the 745 bits off to less enlightened people to fund a modern build

grey ghost, send them to me so I can turbo my e23.

This may very well happen.
I'd love nothing more than spending three or four days taking my time bolting on a TCD kit.
But that doesn't seem likely on my budget. I guess I'll either have to use my 745 donor or simply stay NA.

[marc79euro645]

with a megasquirt2 to allow tuning you can get 350hp,350 tq
thats lots of fun, get an m102(81-83) early jetronic style intake tube w/ recirculating intake, also m102 wastegates have stronger springs=higher boost. bigger injectors, arp studs, wideband, clutch, fuel pump,exhaust. It still ends up costing to play!
marc