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OK so I replaced my TD04 (remapped) with a freshly done TD04 hybrid w/billet compressor and got it mapped. Car is v5 WRX wagon, mods are sports cat downpipe, high volume fuel pump and aftermarket panel filter. While peak power is increased a bit, torque is DOWN, boost is DOWN, spool is SLOWER. Outcome is considerably worse than I'd expected. Dyno pics below, blue is old turbo and map, red is new. Any and all clues and advice welcome.
The red line on the second graph shows the boost and its barely hit 1.0 bar on new turbo. Not sure why that would be, but no wonder its no better, as the boost level is much lower than before. You have actually got a power gain despite this so I'm guess it IS flowing a little better (more efficient) at higher RPM. But I'd imagine it probably feels worse than before.
So need to check for leaks on exhaust side pre turbo and inlet side post turbo, and check that it wasn't struggling to make boost (e.g. mapper hit 100% on the boost control solenoid just to get anything). However the boost control is very poor on the new turbo so I'd suggest something amiss. Is the wastegate actuator arm tensioned enough? Wastegate completely closed with no pressure in the vacuum line?
Also how was RPM measured? Inductive on ignition lead? Looks like a bit of a misfire at 4800rpm if so, or could just be dodgy dyno.
Seems odd as my hybrid is mapped to 1.4 bar and boosts to that your mapper really should, of known why it was under performing who mapped it out of interrest
Last edited by Russell38; 14 February 2019 at 11:32 AM.
no, no sign of either. Actuator looks stronger that previous. Certainly opens faster because I can hear whoosh noise when it does. Not tried getting on boost with hose actuator hose removed to see if it feels better.
yeah there was some misfire. I've since changed plugs, though it might have been IACV, which I've also since changed. But boost was down from earlier in the rev range as well. Is there a simple way to check for boost leak? I can't smell exhaust fume at all.
from memory it just wouldn't boost to more than about 1 bar. Mapper said it does sometimes happen, but it does seem odd. I got piping changed post-turbo, and throtle body cleaned, so I'll take it back to him for a road mapping and see what comes of it
most garages should have a boost leak testing kit they can stick on it, little bit of pressure will show if there's air escaping anywhere. Also if it's leaking boost pressure it should stand out when mapping as the fuelling will be much richer than before and you'll have to lean it out in the map to compensate (or fix the leak being the better option). The wastegate preload should be adjustable, normally comes preset on a new turbo though and you should see at what pressure the actuator starts to move when doing the boost leak test.
if there was a problem with it not making the correct boost he shouldn't of carried on with the mapping. the turbo should be making 1.35 to 1.4 bar was there no feedback from the mapper with suggestions on what to do
Last edited by Russell38; 14 February 2019 at 08:36 PM.
What injectors are you on? A quick spot the difference between your spec and mine makes me think that that's the route cause. Might also be the reason why the mapper hasn't gone for more boost as the standard WRX injectors won't deliver enough fuel to keep the AFR healthy at higher boost (remember that the hybrid will be providing a higher mass flow rate of air than the standard TD04 will at the same boost, hence why boost has been turned down). I'm on 550cc STI pinks and it made something like 304bhp and 303lbft @ 1.3 bar.
I remember another guy on here who had the same spec as you and got circa 285bhp and was told that the injectors were maxed out.
What injectors are you on? A quick spot the difference between your spec and mine makes me think that that's the route cause. Might also be the reason why the mapper hasn't gone for more boost as the standard WRX injectors won't deliver enough fuel to keep the AFR healthy at higher boost (remember that the hybrid will be providing a higher mass flow rate of air than the standard TD04 will at the same boost, hence why boost has been turned down). I'm on 550cc STI pinks and it made something like 304bhp and 303lbft @ 1.3 bar.
I remember another guy on here who had the same spec as you and got circa 285bhp and was told that the injectors were maxed out.
if injectors where max'd out youd have thought the mapper would have mentioned it
To be honest, it will probably be running 440 injectors which I've seen a few people run around 350bhp region, although at that level they will be maxed out. 300 will be fine though.
To be honest, it will probably be running 440 injectors which I've seen a few people run around 350bhp region, although at that level they will be maxed out. 300 will be fine though.
I thought they were 380cc as standard on WRXs, were they bigger on earlier cars?
To be honest, it will probably be running 440 injectors which I've seen a few people run around 350bhp region, although at that level they will be maxed out. 300 will be fine though.
Originally Posted by LiamB
I thought they were 380cc as standard on WRXs, were they bigger on earlier cars?
Originally Posted by BrownPantsRacing
Ah right yes, you could well be right there. That could be an issue then but does seem weird the mapper didn't make this clear at all.
EDIT
1999 JDM v5 EJ205 WRX or EJ207 STI; wagon or saloon - injectors 16611AA370 although googling the part number throws up pink top feed (565) or yellow side feed (440 ?)
Last edited by Don Clark; 15 February 2019 at 01:16 PM.
Reason: googled part number
EDIT
1999 JDM v5 EJ205 WRX or EJ207 STI; wagon or saloon - injectors 16611AA370 although googling the part number throws up pink top feed (565) or yellow side feed (440 ?)
I'm sure they wouldn't have been 550's in a V5 WRX, but they could well have been 440s then. I seem to get conflicting info when I search.
if there was an up pipe leak,what would I expect to see? Would it match what the dyno read? Or if there was a leak after the turbo, i.e. a boost leak, would that be more of a match with what we saw?
13 February 2019, 09:19 PM
crap TD04 hybrid upgrade. Help.
