B4 Legacy Mods

[Jono24]

Hi, I'm reasonably new here and been reading every page on the web i can find about my model and modifications i can find.

My B4 is the Rev A, it has the vf26/vf27 turbo combo (it's a manual). I've put some 4 pots on the front and a genome strut brace and that is it so far.

Now the tricky part, getting more hp. an exhaust and a piggy back is my train of thought, but i'd like to hear from others with experience (please don't suggest single turbo) as to how loud the exhaust will be and how reliable the engines can be expected to be after these mods (how much more stress on the engine and where?).

a 255 lph walbro is also on the shopping list.

I've been looking at a rage 2.5" system turbo back, (twin 2.5" dump pipes, 2.5" y-pipe, 2.5" back to muffler), I want to know if other people have run similar and what they would do differently (the aim is more usable hp without to much noise), i.e, would you have another resonator in it? magoo muffler in chch here said to expect $1200 for said system.

For a piggyback i'm keen on an hks f-con. i know these are probably on the expensive side but i've only heard good things about them (i know they can only be tuned by hks dealers...) and i do need this car to be reliable (understanding regular maintenance is always necessary). if you have any other suggestions on a piggyback that can handle the twin turbos i'm listening

I've found the guys on ozliberty were getting 200-220kw at the wheels with similar sort of stuff but haven't heard how long these cars last and where they crap out, i understand the single turbos put out this sort of power reliably (? am i wrong here) on standard internals so where is the weak point in the twin.

also will the hks f-con be able to control boost? i haven't heard if they can, if they can that's great but otherwise i'll probably need a boost controller (won't i?)

thanks guys

[Scoobydoo]

A number of people have used the Zerosports Sequential controller to good success. Although it won't increase your power as such, it will give it a nicer delivery so it won't feel like there's a big loss of power between the two turbos (called Valley of Death, if you're not aware). This is a common upgrade for the people who like the TT systems.

That exhaust system should be good, but no idea on how loud it would be. My suggestion would be to get it, and if it's to your liking (and your wof-issuers liking) then sweet, but if it isn't, then get another resonator put in afterwards. Easier to do that, than get it put in, decide it's too quiet, and have it removed!

[aim]

Extracting more power from these is always a bit of a gamble - it depends on how it's been serviced and how it's been treated. They're actually really reliable cars if you treat them well and service them regularly... stock. No third party can guarantee you a reliable increase in power. If you want to 'feel' more power, the upgrade scooby suggested is a good one, it can give you more of a kick or deliver a smoother torque curve and hopefully eliminate that VoD. And in general make the earlier revisions a much nicer car to drive.

Or you could buy a Rev D and have no VoD in the first place. I believe people have more success extracting power from the BL/P legacies than the BE/H. If you want more powerful cruiser, buy an H6 BL and turbo it

[D-Style]

Have a look at Fortyone.co.nz for a few different J-Land exhaust brands. A good number are nice and legal for road use.

Zerosports Controller and CAI mod.

Samco Turbo-I/C pipe kits are good if you can find one.

Boost control is best left to a EBC which have RPM point Control like an Apexi AVC-R. That way you can keep the primany boost the same and raise the Secondary boost a little more.

Piggy-back computers are limited, but do offer some adjustment. there are a few Haltech, Unichip, Trust. Get the one with the best local support and knowledge with turning.

I would suggest, dropping the sump and giving the sump and oil pick up a good clean.

Theres a good reason why so many people are going to tell you to go single turbo. After you blown and replaced a primany turbo and/or BEB a few times, you see why people sugguest it.

If you want big gains and must keep the TT setup, you will be going into the R&D mods = $$$

In short theres only a few simple mods you can do, and even then the risk of the primany going tits up increases. Some have had no troubles after mods, some have..its the subaru game of chance.

[Jono24]

thanks for the help so far, forgot to mention i have another vf27 coming and i plan to swap the bb chra out and put it in the vf26 primary (these primaries are journal/thrust bearings from everything i've read and are a direct swap with the secondary).

Thanks D-style for the tip on cleaning out the sump and pick up, i hadn't heard of that but it sounds completely logical and a source of half of the primary turbos crapping out early (poor maintenance!).

From what you've also told me is that the first and major weak point of the engine is that primary turbo. and a td04 primary hybrid is sounding better and better to get what i want. (i'll keep an eye out for cheap td04's and vf18's to bastardise).

i've seen an avc-r on tm so will keep look out for those (been eyeing one up already).