does an sti intercooler on a wrx running 340bhp really need i/c spray?
22 December 2008, 02:05 AM
#31
The water spray is fitted to some O/E Subarus simply to allow them to be homologated on rally cars. There would be no waterspray on road cars if it were not for the homologation requirements.
The purpose of the water spray is to dissipate heat after prolonged periods at a standstill. eg at the start line for a stage. The effect on ACTs while running is less signifigant and the weight of water that would be required to run it permanently is prohibitive.
The spray is on to the TMIC fins and for best results, this has to be in a very fine spray or mist.
It does NOT cool the turbo per se where the exhaust side needs to be as hot as reasonably possible and the compressor side kept cool.
sc00bystu:
Can you explain this please. Which front mounts cause lag and what sort of air charge temperatures have you observed on cars with TMICs and where and how were you measuring the temperatures?
While I know some cores, both TMIC and FMIC can be laggy it is often down to poor core design or manufacture or a mapping issue.
The point at which a Subaru will have a clear benefit from an FMIC will depend on the model and power output. Slanted TMICs 93-96 were probably inadequate well before 300 bhp. 97-98 cars probably around 300 bhp or marginally over and ver 5 and 6 cars around 320 bhp. On the New Age cars the WRX is comfortable to around 350 bhp and the STi a bit more than that.
If you are not monitoring ACTs on an ongoing basis in a variety of driving conditions on both TMICs and FMICs then I don't see how you can have an accurate opinion to compare what works or what does not or the effects on ACTs from applying the water spray, both on the move and after heat soak.
The performance of an intercooler is usually referred to as x degrees over ambient so you really have to monitor ambient too but the temperature over ambient is only slightly less in winter than in summer. On a good set up the difference is quite small, summer to winter.
Butty : Remember there will be a pressure drop across the intercooler core. How big a drop will depend on the quality, or lack of quality of core design and manufacture. Think about the phenomenom of carburretor icing. The temperature can be 20 degrees C but the carb can still ice up and especially so with the right relative humidity.
Also be aware for those of you that are not, that a mix of 50% water/metanol will be more effective in disipating heat than straight water. Latent heat, evapouration and all that.
The purpose of the water spray is to dissipate heat after prolonged periods at a standstill. eg at the start line for a stage. The effect on ACTs while running is less signifigant and the weight of water that would be required to run it permanently is prohibitive.
The spray is on to the TMIC fins and for best results, this has to be in a very fine spray or mist.
It does NOT cool the turbo per se where the exhaust side needs to be as hot as reasonably possible and the compressor side kept cool.
sc00bystu:
front mount equals lag!
its in the perfect place for instant responce pluss it doesnt get hot enough in the uk to matter!
its in the perfect place for instant responce pluss it doesnt get hot enough in the uk to matter!
While I know some cores, both TMIC and FMIC can be laggy it is often down to poor core design or manufacture or a mapping issue.
The point at which a Subaru will have a clear benefit from an FMIC will depend on the model and power output. Slanted TMICs 93-96 were probably inadequate well before 300 bhp. 97-98 cars probably around 300 bhp or marginally over and ver 5 and 6 cars around 320 bhp. On the New Age cars the WRX is comfortable to around 350 bhp and the STi a bit more than that.
If you are not monitoring ACTs on an ongoing basis in a variety of driving conditions on both TMICs and FMICs then I don't see how you can have an accurate opinion to compare what works or what does not or the effects on ACTs from applying the water spray, both on the move and after heat soak.
The performance of an intercooler is usually referred to as x degrees over ambient so you really have to monitor ambient too but the temperature over ambient is only slightly less in winter than in summer. On a good set up the difference is quite small, summer to winter.
Butty : Remember there will be a pressure drop across the intercooler core. How big a drop will depend on the quality, or lack of quality of core design and manufacture. Think about the phenomenom of carburretor icing. The temperature can be 20 degrees C but the carb can still ice up and especially so with the right relative humidity.
Also be aware for those of you that are not, that a mix of 50% water/metanol will be more effective in disipating heat than straight water. Latent heat, evapouration and all that.
Last edited by harvey; 22 December 2008 at 02:21 AM.
22 December 2008, 02:13 AM
#32
BANNED
Join Date: Nov 2008
Location: UK
Posts: 272
Likes: 0
Received 0 Likes
on
0 Posts
id say no not at all, ur pref at end of day if u want water peeing inside your engine bay then yea. at the mo im trying to come up with an idea to get the air passing back into the engine a bit more cooler watch this space :-?
22 December 2008, 07:50 AM
#33
Scooby Regular
Join Date: Jun 2008
Location: Midlands
Posts: 393
Likes: 0
Received 0 Likes
on
0 Posts
Sorry, cooler than the air temp in the engine bay.
