I have an early WRX fitted with a TD04 turbo as standard. Now I know these smaller turbos are better for low down torque but perhaps not so much power high rpm.

But I have also read that 97-99 uk turbo impreza's were fitted with the td04 and they performed better than the early imprezas. I've also heard of people removing TD05 and replacing with TD04 !?

So what's the better turbo to have? Of course it depend on your power goals. I have VOS chip in the post that should improve engine performance significantly, bumping my boost up to 16psi and giving a better AFR. I also have dcat and downpipe. I want to reach around 260 BHP but don't expect to want more after that. Will I be limited by the TD04? Should I source a TD05?

Any TD04 vs TD05 debate appreciated

 

tdo4 or tdo5 if you are only going to run 16 psi of boost id rather have the tdo4 , plus if your only after 260bhp the tdo4 is the best for you youll need a lot more mods to make the tdo5 perform better than a tdo4 , john banks mapped my car for a tdo4 a and as soon as got all my exhaust leaks sorted the car car was mint swapped to a tdo5 and hated it until i got an apexi ecu fitted now the car is mint

 

For 260, I'd go with the 04, It will run out of puff at the top end, but overall the car would be better to drive.

Dave.

 

Havnt the early WRX's allready have TD05 as std?

 

Not the wagons like mine. They used a TDO4 for more low-down power, the idea being that it would be more suitable for carrying large loads and towing etc.

 

Ahhhhh,i see-thanks

 

mine has the td05 and I don't like it

the turbo cuts in too late

I mean where can you drive a car over 100mph when this turbo really performs ?

:-)

 

I'll swap you a td04 for your td05 no problem

Andy

 

I had a 97 JDM Forester that had a TD04L turbo, but with twice the number of vanes than UK 99-00 Impreza turbos.
It may be this version of the TD04 that you are referring to - also fitted to Impreza JDM WRX wagons up till about 98? It gave extra torque at 2000-3000 rpm but lost out power from about 5000 rpm to the TD04 with fewer compressor vanes.

With very basic mods I moved from 240 up to 260 bhp, but not a lot more torque - still, with 160 rising to 240 lbft, it was good for towing and load lugging.
I raised the boost of this to 16.3 psi, falling to constant 11 psi and was still 8% CO at 6000 rpm in 3rd gear.
If 260 bhp is your target then it sounds like you already have the components available.

Nick

 

Val113r

I have my Bugeye TD04 turbo in the garage(not on the car)... as Andy F says I'll swap it for yout TD05

It's all in the (Bob Rawle) Mapping !!

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