Pros and cons of front mount intercooler please..
03 July 2016, 04:14 PM
#93
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Yep
Yep that's my old car .....
I'm using the Grimmspeed tmi taken from that hatch and installed in a new MY2016 Sti running a 2.35 and the same Xtr2.5 turbo.
Now pushing 475bhp @ 1.65bar. Lovely road car.
Grimmspeed make quality kit.
I'm using the Grimmspeed tmi taken from that hatch and installed in a new MY2016 Sti running a 2.35 and the same Xtr2.5 turbo.
Now pushing 475bhp @ 1.65bar. Lovely road car.
Grimmspeed make quality kit.
Have a read of this . . .Grimmspeed TMIC producing good results
https://www.scoobynet.com/scoobynet-...ner-tales.html
https://www.scoobynet.com/scoobynet-...ner-tales.html
03 July 2016, 05:12 PM
#94
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The airflow into the scoop looks pretty reasonable. The only way I can see you'd have any problems is if the air pressure in the engine bay gets higher than that from the scoop (that'd do a pretty good job of killing the airflow through the intercooler) but I'm led to believe the engine bay is designed to flow air out through the transmission tunnel.
http://www.type-ra.com/subaru-forum/...parison.11447/
03 July 2016, 06:08 PM
#96
The airflow into the scoop looks pretty reasonable. The only way I can see you'd have any problems is if the air pressure in the engine bay gets higher than that from the scoop (that'd do a pretty good job of killing the airflow through the intercooler) but I'm led to believe the engine bay is designed to flow air out through the transmission tunnel.
http://www.type-ra.com/subaru-forum/...parison.11447/
At what speed was the air flowing ??? Reports and tests I've read over the years suggest the scoop becomes far less effective at speeds above 120mph...
Also, the issue regarding scoop airflow is worse in earlier cars. This would be the reason the scoop grew in size over the years I would imagine.
03 July 2016, 08:12 PM
#98
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At what speed was the air flowing ??? Reports and tests I've read over the years suggest the scoop becomes far less effective at speeds above 120mph...
Also, the issue regarding scoop airflow is worse in earlier cars. This would be the reason the scoop grew in size over the years I would imagine.
Also, the issue regarding scoop airflow is worse in earlier cars. This would be the reason the scoop grew in size over the years I would imagine.
03 July 2016, 08:30 PM
#99
On full runs to get the proper figures we run the tunnel at 80MPH, then extrapolate the values up to 100MPH.
03 July 2016, 08:34 PM
#100
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When doing visual checks you run the tunnel speeds low, because you have to stand in the airflow with the smoke wand, even at 30MPH its hard work to stand up and hold the wand. We tend to run them sub 30MPH when doing that.
On full runs to get the proper figures we run the tunnel at 80MPH, then extrapolate the values up to 100MPH.
On full runs to get the proper figures we run the tunnel at 80MPH, then extrapolate the values up to 100MPH.
03 July 2016, 09:23 PM
#102
some of the front mounts on the market are so bad you would be better off with a stock TMIC.
Proper IC core material is expensive to manufacture, so whichever position you use the results will be determined by how efficient the core material is and how much airflow that core is able to flow.
The airflow through a FMIC on a stock layout is pretty dire as you have the air con and water radiator in the airflow path, then it has to get past a very wide flat fronted engine. The downside to the TMIC is you have the gearbox in the way of the exit airflow.
Like most things the normal road car solutions are big compromises, if you are building a proper competition car then there are big gains to be made from packaging designs, just looking at the WRC Impreza solutions shows you how to make it work efficiently.
If you look at the size of my TMIC and then compare it to most FMIC on the market, it's tiny, yet it will outperform them because the core is efficient and the airflow through it is very good. Now think about the benefits of weight distribution, weight in total and pipe lengths and the TMIC makes a very good case for itself compared to most FMIC in use.
From my own experience, over 500BHP is easily achievable on a good TMIC, my own has amazing charge temp control, once on the move it sits at ambient air temp and doesn't climb much on load. Heat soak is obviously an issue but you also get significant heat soak on a FMIC too, for most its an irrelevance, worst case scenario is sprinting and I've yet to have any issues. I've seen my competitors with FMIC using CO2 extinguishers to try and reduce their own heat soak issues.
The engine doesn't care where you mount the intercooler, all it cares about is having the coolest air into the cylinders, throttle response is a result of the turbo design and the lag between throttle application and the resulting airflow, engine spec and engine mapping.
Proper IC core material is expensive to manufacture, so whichever position you use the results will be determined by how efficient the core material is and how much airflow that core is able to flow.
The airflow through a FMIC on a stock layout is pretty dire as you have the air con and water radiator in the airflow path, then it has to get past a very wide flat fronted engine. The downside to the TMIC is you have the gearbox in the way of the exit airflow.
Like most things the normal road car solutions are big compromises, if you are building a proper competition car then there are big gains to be made from packaging designs, just looking at the WRC Impreza solutions shows you how to make it work efficiently.
If you look at the size of my TMIC and then compare it to most FMIC on the market, it's tiny, yet it will outperform them because the core is efficient and the airflow through it is very good. Now think about the benefits of weight distribution, weight in total and pipe lengths and the TMIC makes a very good case for itself compared to most FMIC in use.
From my own experience, over 500BHP is easily achievable on a good TMIC, my own has amazing charge temp control, once on the move it sits at ambient air temp and doesn't climb much on load. Heat soak is obviously an issue but you also get significant heat soak on a FMIC too, for most its an irrelevance, worst case scenario is sprinting and I've yet to have any issues. I've seen my competitors with FMIC using CO2 extinguishers to try and reduce their own heat soak issues.
The engine doesn't care where you mount the intercooler, all it cares about is having the coolest air into the cylinders, throttle response is a result of the turbo design and the lag between throttle application and the resulting airflow, engine spec and engine mapping.
03 July 2016, 09:47 PM
#103
some of the front mounts on the market are so bad you would be better off with a stock TMIC.
Proper IC core material is expensive to manufacture, so whichever position you use the results will be determined by how efficient the core material is and how much airflow that core is able to flow.
The airflow through a FMIC on a stock layout is pretty dire as you have the air con and water radiator in the airflow path, then it has to get past a very wide flat fronted engine. The downside to the TMIC is you have the gearbox in the way of the exit airflow.
Like most things the normal road car solutions are big compromises, if you are building a proper competition car then there are big gains to be made from packaging designs, just looking at the WRC Impreza solutions shows you how to make it work efficiently.
If you look at the size of my TMIC and then compare it to most FMIC on the market, it's tiny, yet it will outperform them because the core is efficient and the airflow through it is very good. Now think about the benefits of weight distribution, weight in total and pipe lengths and the TMIC makes a very good case for itself compared to most FMIC in use.
From my own experience, over 500BHP is easily achievable on a good TMIC, my own has amazing charge temp control, once on the move it sits at ambient air temp and doesn't climb much on load. Heat soak is obviously an issue but you also get significant heat soak on a FMIC too, for most its an irrelevance, worst case scenario is sprinting and I've yet to have any issues. I've seen my competitors with FMIC using CO2 extinguishers to try and reduce their own heat soak issues.
The engine doesn't care where you mount the intercooler, all it cares about is having the coolest air into the cylinders, throttle response is a result of the turbo design and the lag between throttle application and the resulting airflow, engine spec and engine mapping.
Proper IC core material is expensive to manufacture, so whichever position you use the results will be determined by how efficient the core material is and how much airflow that core is able to flow.
The airflow through a FMIC on a stock layout is pretty dire as you have the air con and water radiator in the airflow path, then it has to get past a very wide flat fronted engine. The downside to the TMIC is you have the gearbox in the way of the exit airflow.
Like most things the normal road car solutions are big compromises, if you are building a proper competition car then there are big gains to be made from packaging designs, just looking at the WRC Impreza solutions shows you how to make it work efficiently.
If you look at the size of my TMIC and then compare it to most FMIC on the market, it's tiny, yet it will outperform them because the core is efficient and the airflow through it is very good. Now think about the benefits of weight distribution, weight in total and pipe lengths and the TMIC makes a very good case for itself compared to most FMIC in use.
From my own experience, over 500BHP is easily achievable on a good TMIC, my own has amazing charge temp control, once on the move it sits at ambient air temp and doesn't climb much on load. Heat soak is obviously an issue but you also get significant heat soak on a FMIC too, for most its an irrelevance, worst case scenario is sprinting and I've yet to have any issues. I've seen my competitors with FMIC using CO2 extinguishers to try and reduce their own heat soak issues.
The engine doesn't care where you mount the intercooler, all it cares about is having the coolest air into the cylinders, throttle response is a result of the turbo design and the lag between throttle application and the resulting airflow, engine spec and engine mapping.
So..... when does a front mounted intercooler (let's say an expensive cored one) become a better option than a top mounted one of any description ?
You say over 500bhp is easily achievable on a good top mount.... does that mean there's a limit to how much power a top mount would work with??
04 July 2016, 11:01 AM
#104
The limit will be determined by the thermal capacity of the IC installation as a whole, be that front or top mount. I don't know the limit of my top mount. It's a well proven solution in Time Attack and sprinting at 500BHP, you would have to ask Chevron if its been used on bigger power than this.
04 July 2016, 01:53 PM
#105
The limit will be determined by the thermal capacity of the IC installation as a whole, be that front or top mount. I don't know the limit of my top mount. It's a well proven solution in Time Attack and sprinting at 500BHP, you would have to ask Chevron if its been used on bigger power than this.
Nicely dodged
Begs the question why so few big power builds use a top mount intercooler. Some of which are built and tuned by some pretty knowledgeable people...
Paul for instance who mapped your car, he ran a front mount in the ZEN car I believe didn't he ??
.SJ.
04 July 2016, 02:02 PM
#107
Only person who ran a tmic (size of a fmic) out of the tuners was andy f on his blue sti 5 type r think it was running mid 500s at the time
http://www.andyforrestperformance.co.uk/27032.html
http://www.andyforrestperformance.co.uk/27032.html
Last edited by banny sti; 04 July 2016 at 02:05 PM.
04 July 2016, 06:06 PM
#108
Originally Posted by banny sti
Only person who ran a tmic (size of a fmic) out of the tuners was andy f on his blue sti 5 type r think it was running mid 500s at the time
http://www.andyforrestperformance.co.uk/27032.html
http://www.andyforrestperformance.co.uk/27032.html
04 July 2016, 08:42 PM
#111
The usual reason people use a FMIC is cost and doing what everyone else does. Its cheap to use a FMIC, that doesn't mean its the best solution overall.
The best solution if using a FMIC is to get rid of the water radiator out of the airflow for the IC core and use a short pipe run, then duct the exit airflow out of the bonnet, as found on the WRC cars, but that's not a practical solution for the majority of people just wanting to tune their road car.
Guys like AndyF will back up what I say, what matters is the thermal efficiency of the install, its always better to try and keep the pipework volume to a minimum for throttle response.
On the group C Le Mans cars I've race prepared they have the intercoolers at the rear of the car, fed via the airflow down the side of the bodywork, they use highly efficient core materials similar to my TMIC. All that matters in terms of efficiency is the core material and the airflow through it, getting hung up on location is just not thinking it through properly.
When I first drove the Zen time attack car, prior to it being a dedicated competition car, it used a FMIC, I then drove it when it was beginning to become more of a proper competition car and it used a charge cooler, that wasn't up to the job. Paul then fitted a FMIC. There wasn't a decent TMIC on the market then and even if there was, because the car was going to be a dedicated competition car, it was easy to make a decent install of a FMIC. Even that was changed on his new TA car as the water radiators were moved to the rear of the car to improve the FMIC airflow (and weight distribution).
04 July 2016, 10:23 PM
#114
05 July 2016, 12:47 AM
#115
Originally Posted by banny sti
Correct
Unlike the monstrosity that is the Blob STi scoop, when on a Classic.
Last edited by joz8968; 05 July 2016 at 01:33 AM.
05 July 2016, 06:36 AM
#117
Holset was ran at 1.6 bar on the 2.5, I was seeing air temps about 15-20 degrees above ambient after long hard 4th gear pulls, I would say that was about the limitation of the small chargecoolers effecientcty. With a 16g and circa 350hp it as very good, I'm now putting my 7th turbo on the fourth engine in this car, a 20g on a new 2.5, I dare say it will cope very well with this turbo setup, and response should be good.
05 July 2016, 11:36 AM
#118
As it seems a really efficient TMIC works very well why has no one experimented with the scoop size to make it work even better? Or have they? I don't mean swapping a Bug scoop for a Blob scoop (or whatever) but actually fabricate an entirely different and more effective scoop. After all those scoops were intended for relatively low power road appications. It might look hideous but in a race scenario that's not relevant.
