running bigger exhaust housings on turbos

[scoobygt]

got a vf26 turbo with a stuffed exhaust housing and i\'m wanting to know what would happen if I put a bigger exhaust housing on it off a vf20 I have lying round.. would it cause more lag or would I gain power or maybe even have quicker spool up?

[Guest]

How sensitive is your wrinklepiece? But really if you have it why not but I would think the diff would be negligible.

[funkytown]

You need to match the housing to the wheel first right... if not it will blow goats... massive goats.

If say you were going from a low AR to larger AR in the same turbine size inducer / exducer then you could start measuring gains / losses but would depend on a lot of things

[scoobygt]

its just that the vf26/27 combo was the best upgrade for the twin turbos and flowed the most out of all of them blah blah, I just didn\'t want to compromise any thing.

[scoobygt]

the vf13, vf18, vf20 all share the same exhaust wheels apparently, it\'s the secondary turbos that start changing sizes.

[Marky]

Sure it fits? Telemekas will be the man to answer if it\'s doable but I\'m 90% sure the early housings aren\'t straight swaps with the 25/26 centres

Bigger housing means later spool with more potential - for example like... google difference between .63 and .84 housing on a gt35

On a VF20/26/whatever good luck noticing it I guess - that said I\'m going to bastardise a VF27 into a 26 housing (relatively bolt-in) once it shows up, so I can talk

[scoobygt]

I am actually reading alot of info telemekas has previously written right now, i\'m all for more power up high but I don\'t like lag on the primary turbo!

[telemekas]

 scoobygt said:

got a vf26 turbo with a stuffed exhaust housing and i\'m wanting to know what would happen if I put a bigger exhaust housing on it off a vf20 I have lying round.. would it cause more lag or would I gain power or maybe even have quicker spool up?

The VF26 is a RHF4 (non ball bearing) with a P14 turbine housing.The turbine wheel is a 6200 (cut back design) hence a small inducer diameter.

The VF20 is a RHF4B (ball bearing) with a P16 turbine housing.The turbine wheel is a 4600 with a larger inducer diameter.

The seat depth of the VF20 turbine housing will need to be shaved approx 1-2mm to correctly align the the VF26 turbine wheel.

Therefore from P14-->P16-->with small inducer cutback wheel -->P18++ more top end at the expense of spool up

[scoobygt]

dam its not a straight swap over then :-[ how ever a vf31 with a vf20 exhaust housing is a straight swap??

[telemekas]

No!

The first generation TT turbos VF13-->VF20 have a 12mm seat depth.

The later generation TT turbos VF25-->VF33 have a 10.5mm seat depth.

So the P16 housing will need to be shaved 1.5mm to align the turbine wheel correctly.

Not difficult to do. Once you have had that done the C-clamp will need to be crimped in 1.5mm.

The VF31 with a P16 is a PE1016F equivalent.

[scoobygt]

haha jesus man you know your stuff!

[scoobygt]

i\'m thinking of getting 2 vf14 secondary turbos.. id use the vf14 chra with a vf13 cover and a ar 16 exhaust housing for the primary and also get the wg ported out with a bigger flapper.. then for the secondary id use the vf14 chra and get a ar 18 exhaust housing.. apparently this is the best upgrade you can do before going to tdo4 chra\'s!

[Marky]

 scoobygt said:

i\'m thinking of getting 2 vf14 secondary turbos.. id use the vf14 chra with a vf13 cover and a ar 16 exhaust housing for the primary and also get the wg ported out with a bigger flapper.. then for the secondary id use the vf14 chra and get a ar 18 exhaust housing.. apparently this is the best upgrade you can do before just buying a $300 VF22/3, wrx manifold and ecu

fixed your typo

[Guest]

Hypocrite tho dude... ;D

[Marky]

Oh agreed

Only reason I haven\'t is I\'m in a one-car household at the moment so can\'t have it off the road for the couple days it\'d take me to do the switcho changeo

Have patience haha

[scoobygt]

haha i wish man!