vf27 ball bearing primary t with p18 exhaust housing . plus other turbo sh1tnanigans

[lachlan]

so i just finished my vf26/ 27 ball bearing primary turbo . pretty easy really . cut a spacer out of 1mm alloy sheet and drill and tap 2 m5x.8 holes . . 3 of them line up already and im looking at it going this exhaust housing looks like a runt compared to the vf27 one . like this is **** . looks like one off a 1 liter diesel stationary engine .

i like big housings on turbos . well i hate exhaust back pressure at any stage

im aware all of this is a waste on a car with green afm and grey injectors lol . might fix that one day

look inside the inlet ans its a p14 . google confirms this is right for a 26 . lame . so im eyeing up the spare vf27 p18 housing i have . thinkin the bolt pattern looks similar .

one bolt is the same . one bolt is in fresh meat . one bolt is 30% in another hole . good enough for me

and the entry needs port matching to the primary up pipe anyway . the up pipe is the sixe of that gasket hole

next problem

no waste gate in this housing . theres the castings but no flapper etc . so im pondering how much work it is to uninstall the flapper etc from the p14 housing and re install it in the blank p18 housing

i turned this

into this in about 1 minute flat . turns oout a vf14 has a p18 exhaust housing and already has a wastegate fkn chur

cut the 2 useless bits off and started porting it .

to be continued ...

on another note . who can tell me anything about this . it fits in a lathed out vf26 backing plate . exducer diameter is bigger . inducer is the same and does anyone want it ?

vf27 for comparison

lastly i pulled apart a vf27 for a look . coz thats what im like . fk the bearings are tiny . got them all back in tho

[Jono24]

I'd be interested to see how this bb-p18-vf27 goes as a primary. BB and larger ex housing maybe equal in spool to a vf26 with more potential?

[lachlan]

Yea in reality the entire engine has to breath through the puny ill fitting p14 housing except for the 1 %of the time you drive it on both turbos . I figure it will be more econimic and nicer to drive off boost aswell as better on boost .

I rekon even just tapering the inlet of the p14 would have a noticable effect

Really needa compare on a car that is already running vf 26 27 combo .

Quite interested in exhaust back pressure throughout the rev range also . I rekon I could max these grays and green before I got high enough boost for it to be higher than egbp .

[Guest]

Is that p18 similar in size to a vf24 etc p18?

[Marky]

What you're doing there

I like it

[telemekas]

The VF25/26/27 use 6200 ( 8 blade- cut back) turbine wheel.

The VF13/16/17/18/19/20/21/31/32/33 use 4600 (9 blade -36mm exducer) turbine wheel.

The VF14 uses 5700 (9 blade- 39mm exducer) turbine wheel.

So you can only directly interchange turbine housings that use the same turbine wheel.

[lachlan]

Looks the same ... it spins and doesnt scrape when pushed and pulled on . Appears to have the same clearance around it .

If the inducer diameter and the radius on the edge of the blades is the same then it will work wont it ?

I have a 26 wheel and shaft spare . Ill poke it in and post photos

Edited November 24, 2015 by lachlan

[lachlan]

some photos and carry on as fas ac i can tell the diameter of the 27 vs 14 wheel is within .3 of a mm .

from the ass . but end . 27 wheels in a 27 rear housing and a vf14 rear . but which is which dun dun dun

vf 26 exhaust wheel in a 26 27 and 14 rear housing

and some things i did with a router

[slystiguy]

Do a compound setup

You wont'... you've changed

[lachlan]

There is no need for a compound setup on a petrol . Ever . You can run 60 psi plus out of a single stage . Diesels however love compound setups . 120 psi out of 3 stages

[natho]

i just put my modded primary turbo on this weekend. i believe the exhaust housing is a p18 - it's a ported one that billsy used on his setup a while ago. vf32 ball bearing chra, vf31 comp cover which is a straight fit. slightly laggier than the stock vf33, with a stronger midrange prior to transition. unfortunately i still have some work to do to minimise the VOD, but i'm leaving this until the rest of the mods are done. up next are dump pipes (still stock), a ported ecv and ported exhaust housing for the secondary.

if all of that doesn't keep me happy, it'l be time to convert to a single turbo.

[lachlan]

So I finally fixed the car and started thrashing it .

It works . It doesnt make real boost till 3k . But thats what I wanted . Its at 3k at 100 kph . So it drives nice like a single turbo setup . During normal driving it just drives nicer and not light switch boost .

In all fairness it prolly does need the vf27 rear housing as telemekas said .

Other points .my ecv rod is way too tight . It opens well before 4k

Id like a rev d

What is the rpm limit of a rev d engine ?

Id like to do a lot of exhaust manifold pressure measuring . Run out of things to write . Theres more . Just havent worded it yet .

I really dont see how subaru had all those parts in the setup and got it so wrong . Its like the engineers and programers were trying to make each others lives difficult

[natho]

i found with my modded primary turbo i needed significant tweaks to wastegate duty cycle. i did this in the tune, but you could use a manual boost controller instead.

i looked at using the vf27 in the ported exhaust housing that i have, and while the centre fits the housing, the same doesn't work the other way - the vf31/32 centres don't fit the vf25/27 exhaust housings. i never ended up trying it, i figured the extra space would create more lag, but who knows?

pretty much given up on the TT now and going single again soon. while the ported turbos and ecv do help, nothing gets away from the changeover, and worse, how long it takes the ECV to close again, which is a real problem if you want to shift and end up just on the primary again. it's either 4000rpm or 6500-7000rpm.

[boon]

I have to agree hugely with something you mentioned in here - when you force the entire engine to breath (exhale) through a straw it seriously hurts the in-vacuum power.

While a huge ****-off turbo adds a bunch of lag, it also makes the car drive a whole lot better when you're just pottering around...

[natho]

Guess i'll find out for sure, I have a single VF30 going on in the next few weeks.

I've spoken to someone else who did this and apparently his EJ208 off boost with a GTX3076 feels like a TT on 5psi.

[Guest]

Unless like my car it just felt like a n/a car as the transition into boost was so rapid and smooth you didnt notice it. With the single scroll you could feel the spool up.