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You've had no such issues, then you have and its a very common thing.
Of course you can make sure the pipes don't blow off with some decent installation, but you can't deny its a common problem. When the front pipes blow off you get get a lot of stones and **** going into the engine if you are unlucky.
The TMIC simply wont allow it to happen because of the mechanical installation of the pipework.
I'd suggest you need to learn to read and digest...
None of the hoses/pipes of my FMIC kit have ever blown off.
The hose from the turbo to either a FMIC's OR a TMIC's first inlet pipe is a common component in both setups... So has nothing to do with your so-called weaknessess of FMIC kits' hardware.
This is clearly a topic that has many people devided. So what do people running a FMIC do about a CAIK. Doesn’t the pipe work get in the way for a true in wing Kit which I think is possibly the best place to put it to get cool air running to it. There are pros and cons of both set ups surely?
As you can see from ten mins sitting in que at strip the temps went nuts,
My stock airbox equipped car with stock Sti topmount performs alot better i will get a log of that to compare, (This could be down to the Maf being the temp sensor, having it in the manifold would be more relevant to intercoolers)
I also drive a stock(ish) Bug Sti daily so can confirm that there is a noticeable difference in response with the 2.
Another log showing a comparison of my Chevron TMIC with a good quality APS FMIC.
These logs were taken at the 22B.com/MLR Teesside sprint in 2014, my car with the Chevron TMIC and Chevron wing mounted CAIK is compared to Fred Walton's car fitted with an APS DR725 FMIC and APS underwing CAIK.
Same event, same day, both in the same queue for the start.
My ACT trace is the one solid coloured (pink), starts on the line at 44 degrees C, peak on the run is 45.6 degrees, lowest on the run is 37.8 degrees.
Freds ACT trace is the one not coloured in (yellow), starts on the line at 57.6 degrees C, peak on the run is on the start line (heat soak from the water radiator). lowest on the run is 44.8 degrees.
My TMIC suffers less from heat soak and has lower initial temperature from queuing. My highest charge temp is lower than Freds lowest. After the run is over my charge temps continues to drop as i tootle back to the pits, Freds starts to climb again due to heat radiation from the water radiator.
My rpm trace is in blue, as is my gear selected. Freds are in red.
Having seen some actual data, I'm not sure I buy the "fmic is better" mantra as much as before... Perhaps it's better than a standard STI TMIC (at least in terms of flow due to bigger core cross sectional area etc etc), but that Chevron kit seems to be very good (in fact, better than the APS kit according to the data in terms of cooling).
On the subject of lag, I've been in the "FMIC can't possibly add lag" camp for a long time as well, because of the pipe + core volume being something like 20 litres, which is of only 20 revs worth of "intake stroke swept volume" (assuming 100% efficiency), which takes something like 20/4000/60 = 0.30s @ 4000rpm, which probably wouldn't be massively noticeable, however, I now think I've made mistakes in my assumptions, namely:
- if we assume the boost pressure is 1.5 bar instead of 1 bar, it means that we have to fill the pipework + intercooler with 20*1.5 litres of air (= 30 litres -> 0.45s to sweep)
- This is the biggie: I've also assumed previously that it's just a matter of pumping 20(or 30) litres of air, but of course it isn't, because we're in effect filling a pressure vessel that is constantly emptying as well (air escaping into the cylinders)!.
Given the second point there, I can well believe that it takes *far* in excess of 0.30/0.45 seconds to fill to full volume, and here of course a tmic with it's much smaller volume will be significantly better.
I swear I used to think there was a "rubber band" effect when I fitted my FMIC (i think i even posted about that on here back in like 2008), but then I managed to convince myself that I was imagining things, because "0.30" seconds... I now am almost certain that I'm significantly wrong in my previous assumptions.
Perhaps those engineers at Subaru knew what they were up to anyway?
There are a few things to be considered, ultimate thermal transfer capacity matters when you are doing sustained high power runs that would overcome something with a smaller capacity.
There is no benefit of having a large capacity if you aren't ever going to use it, it just adds negatives such as weight and reduced response.
What you should aim for is what is suitable for your requirements, enough capacity at the peak loads you will actually encounter whilst providing a good control and low resistance to keep the airflow optimised for the average load range.
The perfect solution would be no intercooler, if you could get away with it, but that's rarely going to work on a road car on pump fuel.
0.3-0.4s doesnt sound a lot, but in car dynamics its a lifetime when you are using the throttle to rotate the car accurately, its the difference between a balanced slight oversteer exit and time sapping understeer. My car was far too heavy and low powered to compete with what i was up against on paper in the sprints, but the whole package of great brakes (stock with suitable pads for the temperature range), traction (DCCD controller i mapped myself) and punch out of the corners (engine, turbo, good engine mapping and IC design) made a massive difference. My setup in a classic weighing 400kg less would have been bonkers fast.
To answer the question on what happens sat in traffic, its worse with a FMIC, you get more heat soak from the radiator. But in either case the engine map is designed to reduce ignition and add some fuel if the charge temps get high enough to be a problem. You should feel the engine is down on power when you get temps into the range where det could be a problem.
Its why cars like the WR1 often produce crap dyno figures on a rolling road that doesn't have sufficient cooling for a TMIC, the map pulls the power down to keep the engine safe.
If you have had a remap, that's one thing the mapper should ensure is setup properly and if required, enhanced to take account of your mods. If you cant go full chat from standing still in traffic without damaging your engine, the engine map is crap.
Now a log from a typical heat soak situation then run at normal road speeds.
The initial IC temp is from a hot stop then standing stationary to fill up with fuel and pay, followed by a typical drive up to cruise speed through a few town junctions, onto a motorway then off to an A road in traffic.
Ambient temperature is 20 degrees, cruise charge temp is 21.5 degrees, peak heat soaked temp at fuel station is 42 degrees.
Charge temp is always sitting almost at ambient during normal road driving cruise, in the winter it still has the same relationship, so you have charge temps of 2 degrees when it's 0 degrees ambient.
Hopefully all the info given, showing full flat out sustained track use, competitive sprint event use and finally normal road driving is enough to kill once and for all the myths around how a TMIC works.
Bear in mind also my turbo has no heat shield fitted, no turbo blanket and is not ceramic coated, its as bad as it gets in terms of heat soak into the IC sat directly above it. If i were to ceramic coat the turbo or fit a heat shield or blanket the numbers during stationary heat soak would be better.
Water temperature is also shown, that sits at thermostat temperature most of the time on cruise at 85 degrees, i never see over 90 degrees on the road. Fitting a low temp thermostat, which seems the rage at the moment is a bad idea, but that's another story for another thread.
What about the whole " scoop dont scoop at speed" thing then ?
Id imagine regular runs beyond 140mph would push you more towards fmic ?
Its nonsense, i've spent years going to the nurburgring doing 150MPH+ both in an STi5 and my current STi9, the TMIC airflow works. One section of the nurburgring is full throttle in 6th uphill for a very long time.
Its nonsense, i've spent years going to the nurburgring doing 150MPH+ both in an STi5 and my current STi9, the TMIC airflow works. One section of the nurburgring is full throttle in 6th uphill for a very long time.
Would also imagine the journey there involved some high speed autobhan runs too
I will only be running around 400hp anyway, so don't need all those annoying pipes etc in the bay, and I'm pretty sure the sti version will be up to it in my application.
One thing with regards to airflow... I think that in order to have decent cooling from a relatively small core volume, you will end up with pressure drop (because you'd need the air to in effect slow down a bit to havr time to dissipate the heat, and also the core will need to have lots of small holes through it (because you need to maximise surface area for the heat transfer). I'd suggest that unless there is pressure drop, the cooler wouldn't work very well (ie a bar and plate tmic wouldn't work well for tmic, for example, but might work well in a fmic application, because you can have a core volume 10x the size of the tmic (with the response issues etc that brings).
Having said that, I don't think pressure drop across a cooler is a bad thing, and it is kind of to be expected, because the cooler is an obstruction after all.
I will only be running around 400hp anyway, so don't need all those annoying pipes etc in the bay, and I'm pretty sure the sti version will be up to it in my application.
One thing with regards to airflow... I think that in order to have decent cooling from a relatively small core volume, you will end up with pressure drop (because you'd need the air to in effect slow down a bit to havr time to dissipate the heat, and also the core will need to have lots of small holes through it (because you need to maximise surface area for the heat transfer). I'd suggest that unless there is pressure drop, the cooler wouldn't work very well (ie a bar and plate tmic wouldn't work well for tmic, for example, but might work well in a fmic application, because you can have a core volume 10x the size of the tmic (with the response issues etc that brings).
Having said that, I don't think pressure drop across a cooler is a bad thing, and it is kind of to be expected, because the cooler is an obstruction after all.
This is where the money goes, the core material used in the Chevron TMIC is very expensive because of the design of turbulators in the core that transfer heat without the pressure drop. If you look at the core material and then compare it to other options you will see just how much greater a surface area is being worked. Making the end tanks and basic installation fabrication is relatively cheap and costs the same no matter what the core material, the money goes into the core itself.
Factory intercoolers are made to a tight budget, so are never going to perform as well as a high end core, what you need to ensure is the spec you want to run can be catered for with whatever IC you decide to use.
If you don't have an ECU monitoring charge temps, then you can install your own gauge and monitor it yourself, its very inexpensive to set up. That's what i did with my STi5 RA many moons ago now and how i knew the myths about TMIC lack of airflow at speed was garbage.
This is a picture of my charge temp display in my STi5 Type RA 555 WRC Limited i did hundreds of laps of the nurburgring in, taken 15 years ago.
Last edited by johnfelstead; 05 July 2018 at 09:54 PM.
factory intercoolers are made to a tight budget, so are never going to perform as well as a high end core, what you need to ensure is the spec you want to run can be catered for with whatever IC you decide to use.
For sure the OEM intercoolers are made to a price - eg pressed together rather than welded etc etc.
The chevron cores definitely do look the business, but sadly I'm not currently in a position to spend close to a grand on even the budget option... Too many kid shaped holes to fill
My thinking is that I'm aiming for 400bhp (more would be nice) from my billet td06-20g (yes, td06...), which hopefully shouldn't require massive boost pressure, so less heat to extract. Unfortunately, if the IC drops 0.1-0.2 bar across it at say 1.6 bar, then if I want to see a target boost of 1.5 at the TB I'll have to run 1.7 bar at the turbo end, with the extra heat etc etc, so a core that could do the same cooling (or better) at a lower pressure drop would definitely be beneficial. The problem is that I don't have data to back any of this up - the sensible option feels to be to run it with an STI IC and see if temps are a problem on road/track, and change IC if the data suggests there is an issue. But then this comes at the extra cost of a map tweak should the better IC be required - too many variables, argh!
The third option is to run it as is, and get some "baseline" data with the FMIC. This is also the least painful option in terms of cost and time (because it's all already there, installed), and would allow me to get the car on the road and mapped before uni starts again... SORN since march 2012 at the moment...
I currently don't have a temp monitoring system, but I'm half heartedly thinking of building
something with an Arduino (the little programmable hardware board with lots of inputs and outputs), but even a cheap thermometer like you had previously would work.
Oh, out of interest, what intercooler did you run on the RA?
Not sure if it's ever been explained but is there a great difference between the two Chevron TMICs they offer?
I think people look at aftermarket TMICs and aren't prepared to part with big money for them due to its size which is 'small' in comparison to buying a FMIC, getting a big core and lots of pipework, regardless of data logging proof showing the TMIC to be better especially with the Chevron item.
I think but not sure the one John Felstead has is heading toward a couple of grand. Tuners definitely push customers toward a front mount for the certainty and cost effectiveness it provides.
Trev
I think but not sure the one John Felstead has is heading toward a couple of grand. Tuners definitely push customers toward a front mount for the certainty and cost effectiveness it provides.
Trev
Yea kind of like saying single scroll headers spool best,
Then when folk with the twin scrolls show the results you pull out the Killer Bee Holyheader,
When you pay Gucci prices you get Gucci parts (Usually)
Spoke to Simon @ Chevron ref them both. Don’t think it would be fair on him to repeat everything he said. There are clearly advantages over the “race” v the “fast road” version. I won’t lie a large price difference also! It really all depends what your after. Again there are many pros and cons to both, then v a FMIC again. I personally see the facts as being facts (as presented by John). Of course all these things can be played with to suit people accordingly, so “facts” may not always be 100% factual but hay that’s life, must add not suggesting John is lying! Anyway upshot is it’s my money and will spend it as I wish and I will be putting a deposit down on the “fast road” version as soon as I’m back off holiday. Going back to the price, everyone has their own view of these things. Not everyone is mechanically savvy and wouldn’t take on fitting a FMIC themselves. Add to that cutting bumpers etc etc and some will be tempted to pay a garage to do it for them. Add that in and you have added a few hundred pounds to your bill straight away. Fitting a new uprated TMIC is a very easy job in comparison. The Chevron TMIC suits my ultimate plans very well, I don’t want to take a twinscroll motor and slow down it’s spool to drastically but want more grunt. The TMIC fits part of that plan nicely.
I have nothing to gain from giving false information Rorry.
Apart from anything else, frigging the data would see my engine going bang, not something i would risk.
Another couple of images for you, first the data trace from my run at Snetterton, second the engine map configuration for charge temp compensation.
As you can see my ECU map and the data match and the ECU is only pulling out a max of 0.94 degrees ignition at peak ACT, so you can see i'm not doing anything dodgy with the temperature scaling on the charge temps.
01 July 2018, 01:00 PM
