right so some more about this uh bmw project we got in so this is uh an m4 s55 engine
it's had some work done to it in the past by wt motorworks and basically at the point where
they've kind of maxed out the stock turbos or hybrid turbos i think was on this car
and are looking for a you know a more powerful option
obviously hybrids can really only go so far because you've got the limitations of the stock
size of turbine housing and then the you know even with newer compressor covers and things like that
you've there's some limitations involved so that's when realistically the only option is to go to an
aftermarket type turbo like a garrett or an efr and that's what we're going to do on this so
the m4 s55 engine have twin turbos from standard electronically wastegated
that's kind of what we're going to stick with so there are others i've seen
usually in the states where they've got single turbos or big external wastegates
and things like that and it can all be done but the issue becomes actually controlling
the turbo boost control and things like that and you want things as much as possible to work with
as many oem parts as possible and that really is important when it comes to you know the boost
control and if you can keep it if you can keep the stock engine ecu controlling the stock type
electronic actuators to control the boost it's going to be far more reliable and you'll end
up with most likely a far better performing kit i think a lot of the time those kind of
fabricated kits they either don't necessarily make the power they should
make or it's never really something that's um kind of done time and time again
the results aren't necessarily always that either believable or you know there's many downsides to
kind of going away from that oem boost control it's just it's just not not not the best way to
do it so we're going to try and do it with the keeping the electronic actuators so if we take a
look underneath the car now you'll see where the stock turbos are how it all works and then the
space we've got to work with in terms of getting some garage turbos in there so when warren dropped
the car off um he stripped it down partially but i wanted to leave the subframe on um the original
plan was just to whip subprime off because yeah it's not a big job but i think actually having
seen it now we can do all of the work and leave the subframe on um it might make prototyping a
little bit more difficult but you end up having to imagine where less parts go uh and that's
some of the problem again obviously we've got the steering column and the steering rack down and off
and we have to kind of uh take that into account when we're you know mocking this kit up so we want
to remove the least amount of parts that way we can ensure that it's going to fit the best
so the two stock turbos obviously they're quite small because there's two of them so they don't
need to be half as big um the way the down pipes work um kind of move around an engine mount which
sits here um and it all fits quite well you know there's plenty of clearance over to the uh chassis
leg here you've got the stock electronic actuators on and there's plenty of room for turbos of that
size and it's not really an issue obviously we've got to try and fit in a tubular manifold
three inch downpipes much larger air intakes the the garrett turbos have a three inch intake the
intakes on these turbos are tiny i know that there are kind of aftermarket ones which are larger
um but we're basically gonna have two much bigger turbos in here so if you kind of uh
imagine what that looks like and then when i take these out in a minute
and put one of the garrett turbos in you'll see the kind of challenge we've got
right so we've got one of the stock turbos on the bench and one of the garrett turbos
and obviously it's quite a bit bigger that's part of the challenge not only that as standard
the garrett turbos are pneumatically controlled pneumatic wastegate and the bmw ones are electric
so we're going to have to adapt the electronic wastegate actuator onto the garrett turbo
it's not going to be that hard to actually fit that onto there part of the challenge is going to
be that again that actuator is so much bigger than a pneumatic actuator and we're also fitting in
two much bigger turbos it becomes a bit of a challenge to basically cram it all in um
how the so this is the um front turbo i think i'm pretty sure this is the front one um
and as you can see like the the gases come out of the manifold
down into the turbine housing and then actually down and out um it's not the best in terms of flow
uh but it means they get the wastegate in there nicely that sits in the top it's perfectly
designed to fit side by side with another turbo as you can see the intake of that turbo
fits you know nicely up against each other i mean i'm not 100 sure if these the right way
around but even if they're not you know you can kind of see how it works that they're designed
to sit next to each other that one can easily sit in front of there that one can go there
and the garrett ones obviously aren't designed to work that way they're airing air out the back and
that gives us a bit of a challenge in that when you look at the the width of that turbo
this turbo is wider than that one and we've still got a whole weight we've still got
get whole exhaust downpipe out here whereas this one's already coming down
so yeah it's yeah it's going to be a squeeze to get it all in there
but um yeah that's that's part of the challenge so we'll throw one on the car
in the engine bay and uh have a look at what kind of space we've got to work with
it's already a bit of a squeeze getting in there but i'm anticipating that
so we are going to want the front turbo to sit as far forward as possible really
and that is going to be somewhere there i would imagine so
in terms of overall width obviously they're not quite a lot wider than the stock ones it's just
going to be that way that down pipe for the front turbo that's going to cause us most
of the problems we're going to have to get the front turbo as far forward as we get it and the
rear turbo as far backwards as we can get it to allow us to have plenty of room for the downpipe
of that front turbo it's a similar issue to what we had with the skyline um although on the skyline
i think you've got the advantage of being in a position where
you can kind of modify the car a little bit more than you might normally want to
so on this we're trying to keep all of the original fittings where we can as well
so all the original oil return fittings all the original oil feed fittings
coolant we want to try and keep as much of that as possible on the skyline kit that was more of a
it's a more accepted aftermarket part we want this to be as much of a bolt-on part as possible
so there's quite a lot to think about and the first thing really
is going to be trying to set the turbos in a position where they're going to work so
kind of it's going to be a case of throwing a head flange on there or you know two separate headlands
um getting a collector getting a flange tacked on and uh yeah trying to set that turbo position so
that'll be the first thing we do in the next episode i guess so
yeah thanks for watching and keep your eyes peeled