325i Manifold and T3 flange:UPDATE boost gunkys have a LOOK

[oldroydsr4]

Hi all

Just wondering if any body has the dimensions for a m20b25 manifold pand t3 flange. Solidworks models would be great .

Just to note this won't be a batch thing so i'm not using it for personal gain.

I just have access to a cnc machine at work and thourght i would have a go making my turbo manifold.

Cheers

[Ant]

Dave, there's a link to these on any post Alex (turbo brown) has made dude

Go for a log, and use a T4 flange for a HX40, you know you wanna

[oldroydsr4]

Hi ant

I managed to find some dimensions on e30tech so i'm going to have a go.

If i fail, no loss.

contact you soon

[Gunni]

Dave, there's a link to these on any post Alex (turbo brown) has made dude

Go for a log, and use a T4 flange for a HX40, you know you wanna

I feel a split housing should require a split manifold.
otherwise spool up time is delayed. And transient response.

Not going to say anything bad about the HX40 ,

[Ant]

split or proper pulse tuned Gunni ?

a log is fine where space is an issue, and given a big enough hotside would not present a restriction to the engine @ higher Rpms

two of the 2.7T engines I built have comparable turbos ( big trim Hx35 on 18cm, big trim HX40 on 19cm ) spooled within 200 rpms of each other to the same boost levels, the 35 is on a split pulse equal length tubular, the 40 on a simple log.

Perhaps more issues will come to light once the boost levels increase, however it was an interesting back to back comparison @ the time.

Good topic to debate Gunni

[Turbo-Brown]

I've got the T3 flange drawing kicking about if you're still in need

[Gunni]

split or proper pulse tuned Gunni ?

a log is fine where space is an issue, and given a big enough hotside would not present a restriction to the engine @ higher Rpms

two of the 2.7T engines I built have comparable turbos ( big trim Hx35 on 18cm, big trim HX40 on 19cm ) spooled within 200 rpms of each other to the same boost levels, the 35 is on a split pulse equal length tubular, the 40 on a simple log.

Perhaps more issues will come to light once the boost levels increase, however it was an interesting back to back comparison @ the time.

Good topic to debate Gunni

How was transient response, i.e
driving at 3k and then drop the hammer,,
or 4k and so on.

I´ve read a few articles posted by the turbo manufacturers and there it always states that using pulse tuning through the split housing has benefits,

HX40 and 35 I belive can have the same hotside while the compressor is different. can´t really remember on that.

did you log any of it?
I´m really interested in this topic to be honest

[oldroydsr4]

Progress today.

i Wrote the program and will hopefully get the parts made tommorow (boss is out for the day )

I will also do a few designs on solidworks and see which you lot think is the best way to go.

[oldroydsr4]

Hi all, just thourght i would post my progress.

Step 1: Mill side of plates for datum edge on the CNC machine. (please note machine is pretty old so you have to manually change tooles etc)



Step 2:Write program, including centre drill for mounting holes, initial 22mm holes to check cutter wear, followed by full size 34mm holes and finally outside shape.






Step 3: Drill holes accordingly and use the surface grinder to achieve a perfectly flat finish.



Step 4: Flanges finished!! .



Now here is my fisrst design, feel free to be constructive. However a spagetti style manifold isn't really possible

Its using a T4 flange as Ant wants me to run a big HX40

[Turbo-Brown]

I would say smooth the headers off a bit like this:





And then make a smooth collector like this:



And you'll be laughing.

Those flanges look great!

Have you got something nice and sturdy to bolt them down to while you weld them? Guess you can machine them off flat again once the manifolds have settled after welding though

Keep up the good work!

[oldroydsr4]

Thats looks great.

Have found a supplier for 90 and 45 tube through work so will order parts asap.

I have a spare head in the garage and was going to use that for a jig.

[Ant]

V nice gents, I DO like the 3D modelling

[Turbo-Brown]

Tis fookin' handy isn't it?!