Volvo T5 Aquamist tips needed for new user

[Jardon]

Hi all,

I have a 2001 V70 T5 (ME7 electronic throttle). This a 2300cc 5cyl in line engine which produce 250bhp/250ftlbs as standard - this is with peak boost of 0.7 bar. It now runs peak boost of 1.4 bar with a larger turbo (Ported and clipped Mitsubishi TD04 19t instead of standard TD04 16t ) and gets a little hot: IAT's 55C at 6000 rpm and above 40C from 4300 rpm even with a 10C ambient.

The intercooler is standard, injectors are 460cc, free flowing exhaust and manifold.

I make 0.7 bar at 2500 rpm, 1 bar at 2700 and 1.2 bar at 3000 rpm. The peak of 1.4 bar is reached at 3900 to 5000 rpm and I have 1.1 bar at 6000 then 1.0 bar at 7000. I change gear at 5500-6000 rpm as the torque is fading after that and this shift point make best use of my small but ridiculously responsive turbo.

I have fitted the 1s kit but was curious what might be the best jet size (I used 0.7mm but it sounds quite large) and what boost to activate at (from 2500 rpm sound quite early). Also what mixture of water/meth would be suggested? I had not planned to tune for it as I would have thought my IAT's are high enough to cause the ecu to retard timing - or knock with the same result. The cooling/higher octane should by default free up some lost power at the top end.

Many thanks for some advice, Huw.

[Richard L]

If I based maximum fuel delivery of 2300cc/min. I suggest using water to fuel ratio of 10-15%.

10% ... 230cc/min or 0.5mm nozzle)
15% ... 345cc/min or 1mm (1s canonly supflwo 330cc/min)

0.7mm is about mid way. I cannot see why you shouldn't continue using the 0.7mm jet.

[Jardon]

Originally Posted by Richard L

If I based maximum fuel delivery of 2300cc/min. I suggest using water to fuel ratio of 10-15%.

10% ... 230cc/min or 0.5mm nozzle)
15% ... 345cc/min or 1mm (1s canonly supflwo 330cc/min)

0.7mm is about mid way. I cannot see why you shouldn't continue using the 0.7mm jet.

Hi Richard,

My injectors never see more than 80% duty so I based my calcs on 1800cc/min max - this would be at WOT only and I found the car hesitated slightly with the 0.7mm jet/0.9 bar. I decided that IAT's were my main concern so have fitted the 0.5mm jet with great success - 50/50 keeps my IAT's below 40C no matter how hard I drive even wih the ambient above 25C. An amazing difference when you consider they were 55C+ with 10C ambient!

Thanks, Huw.

[Richard L]

In this case, 80% of 2300cc/min = 184cc/min

10% = 184cc/min ........ 0.4mm
15% = 276cc/min ......... 0.7mm

I think the 0.5mm is a good choice.

[Jardon]

Thats what I came up with and I think I'd sooner be at the 10% end if I not mapping for it - I am getting my map tweaked tomorrow and may ask if a little more ignition advance is possible. I hadn't planned to ask for less fuel as I have no failsafe other than my clever Bosch ME7 ECU which should close the thottle/retard/reduce boost at the first sign of knock. I don't think theres much headroom in the existing map to allow an increased ignition advance. Good idea?