Speedtech Twin Scroll N54 bottom mount kit Released

JimboFresh206

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Jan 29, 2018
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Yeah from the pics it looks like his Garret sits higher, and the drain is at a better angle, the BW sits pretty low, and the hotside is what is pretty tight on mine.

I'll try and send a pic later of the WP and rad hose clearance with it moved forward, it is tight, but fits good imo.

For anyone wondering about what I was talking about with the s257 I found the pics of how much I had to port it, and how much it wanted to create a nasty throat.

Another thing I noticed is that BWs sand casted hotsides are no where near as nice as the old style investment cast pieces that used to come standard. I blew through 4 or 5 large pockets of sand, that would have more than likely became friends with my turbine wheels at some point, just like sugar in a tubular mani.


I'm really curious to compare this to someone running one un ported, so if your out there I wanna know lol
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Also, here's the connectors I used for the ADVs, they are working flawlessly, I think alot.of the problems people have had with them, is due to resistance issues when splicing the harness. I know I've run into this in the past with other cars, so I wanted to stay away from that, PM if you want the part numbers for the plug housings and pins :)
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135iSleeper

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May 7, 2019
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I'll report if the water pump can retain the stock location with the precision 6062 when i get to my build.
Nice setup 135isleeper, I plan to wrap everything similar to yours.
Good luck with the install. Yes, the precision looks like it will sit a little different as JimboFresh206 mentioned. Also thanks, I went a little overboard but I thought it would be good to protect the water line since it goes around the hot side of the turbo.

I don't see the inlet fitting with pretty much any turbo and the water pump in it's original home, the relocation bracket worked find for me, fan fit etc... I would just use it :)
It was definitely a tight fit for the inlet fitting on the turbo but it did go on without too much issue. You can see in the image below that there was still a decent amount of room to the front of the turbo and the inlet elbow in the kit fit snug. It probably has a lot to do with the placement and size of the GTX housing as you mentioned.
 

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135iSleeper

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May 7, 2019
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JimboFresh206, I also had to do some grinding to the inside of the manifold for port matching my gasket and turbo (it was only a very small amount compared to your images). The kit didn't come with a gasket for the turbo to manifold so I decided to get one since I felt it would make a better seal than just the high temp gasket maker so I wanted to make sure everything flowed properly.

As far as the ADV sensors, I followed the directions I was given from SpeedTech but I have noticed that I get some interesting O2 related codes after driving for a while. It's definitely possible that the splicing of the wires and having them all bundled up could be causing resistance issues. I even went the extra mile with soldering them stagger and putting individual sleeving around each to try to avoid the issue. I like your idea on how you just changed the connectors. Sent you a PM for the info. Thanks!
 
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JimboFresh206

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Pm replied :)

From the past it was the solder itself that had too much resistance, the oem plugs attached to a set of old 02 leads make it nice and easy to swap sensors too since I only have like 10" of lead from the 02 to deal with (spinning and twisting the wires sucks)

Yeah I was pretty shocked to see how much I had to take down, Jeff warned me about it and I had seen it before on other BWs.

Makes me want to pull the s366 of my 6er and port/gasket match it too lol.

Also fwiw I can pull the turbo with the mani still on the car, just replaced the rear drivers side stud with a nordlock bolt.

I used the oem BW gasket and had the face of the hotside machined down a touch for a nice RA and to hopefully not upset the alignment of the other hot parts... Seems to be working well, and I can have the turbo out in less than an hour! Woo hoo
 
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rac

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Nov 14, 2016
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Will this kit work for RHD?

No. For a bottom mount you need to move the turbo either forward (google leadfoot racing n54), or backwards like 135i2 did. None of the centrally placed ST bottom mounts will work without modification.
 
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JimboFresh206

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Same here, just made the Leavenworth cruise and back, WOT the whole time at elevation, didn't miss a beat :)

With the s257, lag is pretty much non existent, even on just on 12lbs and almost no tuning, an FBO 1er that we went with couldn't hang

@birrcrin who's tuning yours? I'm stuck playing on WG and wanna go fast too lol
 

Jewgo

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Nov 6, 2018
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Same here, just made the Leavenworth cruise and back, WOT the whole time at elevation, didn't miss a beat :)

With the s257, lag is pretty much non existent, even on just on 12lbs and almost no tuning, an FBO 1er that we went with couldn't hang

@birrcrin who's tuning yours? I'm stuck playing on WG and wanna go fast too lol

I am in the same situation (stuck on gate at 12psi). My e-tuner is non-existent. I am not liking the e-tuning process at all. So I am thinking about going to solo motorsports in ATL to get a dyno tune but being from southeast LA, it is about an 8 hour drive.
 
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WOT808

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Abacus38

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Nov 2, 2016
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Make sure you completely drop to the subframe to install this kit. I'm helping someone install the kit who didnt fully drop the subframe and man its a huge PITA. You can get away with not dropping it going top mount but for this bottom mount kit you got to drop the subframe.

Heres a video on how to do it
 

JimboFresh206

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^this was my main motivation on replacing that rear drivers side stud with a bolt.
 

Rafinha

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Jul 8, 2019
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S257 is pretty much the same as the EFR 7670, minus the upgraded CHRA and turbine material. A bit laggy below 2.5k rpm, but pulls all the way to the redline.

Anyone tried this kit with the newer G series turbo from Garrett? They are fairly compact and flow really well, would be perfect for this platform.

I will be trying this kit with a Garret GTX3071R, already ordered the kit just waiting now
 

The Convert

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Make sure you completely drop to the subframe to install this kit. I'm helping someone install the kit who didnt fully drop the subframe and man its a huge PITA. You can get away with not dropping it going top mount but for this bottom mount kit you got to drop the subframe.

Heres a video on how to do it
Not sure about this kit, but I’ve installed fftec and motiv bottom mount kits without dropping the subframe and didn’t have any issues.
 

Payam@BMS

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Oct 27, 2016
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Not sure about this kit, but I’ve installed fftec and motiv bottom mount kits without dropping the subframe and didn’t have any issues.

How did you do that? I couldn't get the FFTEC bottom mount out without removing the subframe. Maybe if you fully removed the motor mount?
 

doublespaces

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Dear God I wouldn't want to try this with subframe in. Some parts are already frustrating enough. Stuff gets tight. Angles get weird. Tools don't fit, even though you've got the right sizes. IIRC, I spent about $1500 in tool refresh prior to my single install.