Hi all


I have a 2004 WRX that has 105,000 miles on the clock. It was my intention to have it mapped a while ago but I haven't got round to it yet. I have a TD04 Hybrid turbo to fit and I need to know what supporting mods I should start buying for the remap.


I am aiming for as close to 300bhp as possible. If I got less than this I think I would be slightly disappointed. I don't mind spending money on parts but I don't want to spend hundreds on just one part if it will only increase power by 2bhp.


I appreciate that the mapper will give input and recommendations but I thought I would first see what people think. At the moment the only things I have are the TD04 Hybrid and a PPP sports cat and back box.


Thanks

 

Full or partial decat.
Definitely get rid of standard up pipe.
Next level up of injectors,440?not sure.
Better panel filter.
3 port boost solenoid and a new fuel pump
This I think is minimum to get 300.
Cheers
Justin

 

To make the most of it without breaking the bank, I'd also include ported, polished and wrapped headers and a Harvey trick up-pipe, plus a turbo blanket. Stock headers you can pick up cheap second-hand (£30 or so) and you can port & polish them yourself. This together with a decent wrap etc will maximise heat retention and speed up the exhaust gases, thereby reduce spool and increasing power, efficiency and response.

The gains won't be massive but appreciable nonetheless, for relatively little outlay.

 

I'd be abit worried mapping a 105,000 mile engine to 300 bhp, just my thoughts.

As has been said

Performance panel filter dry not wet

Sports cat

Uprated injectors

And most importantly uprated fuel pump

You should get close to 300 with all that.

As for polished and wrapped Exhaust manifold, the standard one is good for nearly 400 bhp, so not sure if thats even worth doing as your after 300bhp.

Turbo blanket and wrapped exhaust manifold will increase power slightly, but i can't see its helping in large amounts of power. You best spending your money on things listed in my option. I'd be interested see what others say.

 

Porting and wrapping the stock headers is more of an effort to get the turbo spooling quicker and improve resonse and not really for an overall power increase (shiftin the power band left). Hence using a hybrid td04 rather then just bolting on a bigger turbo to get bigger power numbers. Exactly the route im going once ive reseaerched exactly what billet/hybrid td04 im gona go for. I want a car that makes a really good quality 300hp rather then one that just says a bit more then that on a sheet of paper.

I am goin for pump, sti injectors, y pipe, perrin turbo intake, panel filter, ported stock headers wrapped, sti up pipe wrapped, prodrive sport cat with wide neck mod, 3 port boost controller, remap.
Really want full boost by 2500 and to pull to about 6k at which point id want to be changing gear in my wrx anyway.

Sub subaru do you know exactly what was used to make your hybrid?

And technopug thanks for the help in my thread the most popular seems to be the 19t conversion. I am going to discuss exactly what the company use in the conversion that have quoted me just shy of £500. And see if they have any data before and after etc.
Also going to add heat blanket to the list as well. Thanks.

 

headers.

 

Which company have quoted you?

 

There are a few mods which I will definitely be doing and these are.


1. TD04 Hybrid
2. Uprated Fuel Pump
3. K&N Panel Filter
4. Uprated Plugs
5. Sports cat, deresonated centre, prodrive back box


There are then other mods which I have heard about but which I don't know if they are worth it. e.g. is the small bhp gains worth the cost.


1. Sti pink injectors - £120 ish
2. Sti top mount intercooler and undertray if it fits my scoop (I won't fit Sti top scoop) - £150 ish
3. Some sort of uprated cold air intake by Perrin £315 ish


I don't know what a three port boost solenoid is and how badly I need it?


I don't know what a trick up pipe is and how it differs from the Sti up pipe?

I hear what you are saying about the high mileage and risk of a remap but I guess it is a risk even on lower mileage cars. I also hear of cars just suddenly going wrong so I don't think anything is safe. The only alternative would be to sell WRX as it is and buy an Sti but I don't have the money for that.


Unforunately I don't know too much about my TD04 Hybrid. I bought it off someone in my local club.

 

A trick up pipe is designed for a specific turbo so is optimum diameter for spool but not to small to limit top end power. Very worth while in any application.
And for what the cost it would be mental not to

 

Thanks for the explanation. I need to replace the existing up pipe that has a cat. However, do you think the trick up pipe is worth the cost of £165 over the Sti one second hand for around £50?

 

Only you can decide that. If you want one, better to save up now, rather than have to swap out the up-pipe again at a later date.

 

Sorry for a revival but upon reading a few threads of some hybrid td04 builds, I'm not seing a final post with the results and would like to see the outcome?? As I'm thinking of going the same route. I have a td05 16g in the garage but may sell it to put towards a hybrid
Thanks in advance

 

Very few about unfortunately. I think the hybrids were more popular back before second-hand VF35s became so readily available. Quite a few results from Forester XTs about but not many from Imprezas.

Also, "Hybrid" is not very specific- does it have a 17t compressor or 19t or 20t? Has the turbine been changed - 9/10 or 11 blades? Cut back? What pre and post exhaust is being used. Etc.

All things being equal with a mapped standard TD04, you should expect 10-15% more bhp/lbsft throughout the rev range but the turbo should pull through to 6k, rather than dropping off at 5k.

Very much half way between a TD05/Vf35 and a TD04. You'll start to lose out at higher revs versus the bigger turbos as the smaller turbine remains the same size and that becomes the limiting factor. But the pay off is that spool and low-down power is improved for the same reason; smaller turbine will will build boost quicker.

In truth though, the numbers aren't so important. You should be looking at boost coming in before 2.5k and full boost near to 3k. That would equate to 300lbf/ft at 3k with the ability to hold that to 6k. Should make for a really nice daily drive with instant pick-up throughout the rev range in any gear.

 

Thank you for the informative reply. Il try and source one but sounds like chances are slim. Getting one made is nearly 500 apparently, so with everything else that comes with it I could sell up and get an sti. If I get impatient I guess il stick the 16g on.
Cheers again

 

You could build one yourself for a lot less. It's only a matter or swapping the compressor housing and wheel at it's most basic form.

Also, if you have one built for £500, it will include a full rebuild. So you'll effectively have a brand new turbo. How much do brand new TD05/Vf35s cost?

 

Well the 16g might be roughly the same (guessing) but seems as the vf35 are 350 used I'm guessing alot more!
I see your point 👍