FMIC Lag....
28 February 2011, 01:28 PM
#31
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Alcazar: Not sure what thread you're reading? Maybe a visit to Specsavers is in order 
Tidgy: WRC cars and road cars are completely different. You will also note that on the WRC cars they have done all they can to minimise the pipework length, nothing like most FMIC that people fit to their road cars. Do you really think Cosworth skimped on a FMIC kit?! Have you seen the spec? I daresay that TMIC they use is more expensive than most FMIC kits anyhow.
I think you will find that my first post is accurate and answers the OP's question. Alcazar's statement that it is a "Myth" is incorrect and won't find any reputable tuners agreeing with him.
Even a FMIC salesman will tell you that there is a difference in throttle response between a TMIC and FMIC, it's just logical. Nobody in the know is going to deny that there isn't.
Tidgy: WRC cars and road cars are completely different. You will also note that on the WRC cars they have done all they can to minimise the pipework length, nothing like most FMIC that people fit to their road cars. Do you really think Cosworth skimped on a FMIC kit?! Have you seen the spec? I daresay that TMIC they use is more expensive than most FMIC kits anyhow.
I think you will find that my first post is accurate and answers the OP's question. Alcazar's statement that it is a "Myth" is incorrect and won't find any reputable tuners agreeing with him.
Even a FMIC salesman will tell you that there is a difference in throttle response between a TMIC and FMIC, it's just logical. Nobody in the know is going to deny that there isn't.
what do you notice about the air intake pipework?
it now goes from the back of the engine bay, to the front into the intercooler, then out of it back behind the engine and manifold, isn't that longer than most front mount pipework?
its not just the cost of putting the front mount in, its also a redesign of the entire air intake system thats where the expense is, for a normal tuner car then can just take the old one out job done. Besides which, would cosworth pay full price for the parts? i bet they get one hell of a discount.
28 February 2011, 02:28 PM
#32
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Someone who has been from a TMIC to an FMIC on both a classic and a new age here
1) Boost threshold - Point at which turbo kicks in (or achives specified level of boost)
No difference between the two.
2) Lag - Delay in response to throttle transitions - No quantified difference between TMIC and FMIC that are representative of everyday driving scenarios as far as I'm aware. Some say they feel a difference, some don't. I didn't. If there is a difference it's too minute to be consequential for everyday driving (maybe people who drag the car might feel differently(?) ) AND....
3) If you have upgrade to an FMIC at the right level i.e. when charge temps mean that the TMIC is struggling, then the FMIC will allow the mapper to lean out the mixture slightly and add more ignition advance. My classic took 5 degrees of extra ignition advance gained 20bhp and 30lbs ft torque after a Hybrid FMIC was fitted (no other changes). I'm pretty convinced that the increase would have more than negated any increases in lag, which I couldn't personally discern.
4) Most tuners I have spoken to have said that, although it's adequte to certain levels, a TMIC is fundamentally in the wrong place i.e. on top of a baking hot engine.
The idea, however, that FMICs significantly increase lag IS an SN myth. If there is a difference, it's small and has yet to be convincingly demonstrated (more of a subjective thing I suspect), in contrast to the effects on charge temps and power/torque, which have been convincingly objectively demonstrated by Harvey et al repeatedly.
If you don't need an FMIC, dont bother, as they are a faff to fit, but if you do need one, don't let innuendo about massive increases in lag put you off. With a quality FMIC, the right supporting bits and a good map: It. Does. Not. Happen!
Ns04
1) Boost threshold - Point at which turbo kicks in (or achives specified level of boost)
No difference between the two.
2) Lag - Delay in response to throttle transitions - No quantified difference between TMIC and FMIC that are representative of everyday driving scenarios as far as I'm aware. Some say they feel a difference, some don't. I didn't. If there is a difference it's too minute to be consequential for everyday driving (maybe people who drag the car might feel differently(?) ) AND....
3) If you have upgrade to an FMIC at the right level i.e. when charge temps mean that the TMIC is struggling, then the FMIC will allow the mapper to lean out the mixture slightly and add more ignition advance. My classic took 5 degrees of extra ignition advance gained 20bhp and 30lbs ft torque after a Hybrid FMIC was fitted (no other changes). I'm pretty convinced that the increase would have more than negated any increases in lag, which I couldn't personally discern.
4) Most tuners I have spoken to have said that, although it's adequte to certain levels, a TMIC is fundamentally in the wrong place i.e. on top of a baking hot engine.
The idea, however, that FMICs significantly increase lag IS an SN myth. If there is a difference, it's small and has yet to be convincingly demonstrated (more of a subjective thing I suspect), in contrast to the effects on charge temps and power/torque, which have been convincingly objectively demonstrated by Harvey et al repeatedly.
If you don't need an FMIC, dont bother, as they are a faff to fit, but if you do need one, don't let innuendo about massive increases in lag put you off. With a quality FMIC, the right supporting bits and a good map: It. Does. Not. Happen!
Ns04
Last edited by New_scooby_04; 28 February 2011 at 02:32 PM.
28 February 2011, 04:02 PM
#34
The idea, however, that FMICs significantly increase lag IS an SN myth. If there is a difference, it's small and has yet to be convincingly demonstrated (more of a subjective thing I suspect), in contrast to the effects on charge temps and power/torque, which have been convincingly objectively demonstrated by Harvey et al repeatedly.
If you don't need an FMIC, dont bother, as they are a faff to fit, but if you do need one, don't let innuendo about massive increases in lag put you off. With a quality FMIC, the right supporting bits and a good map: It. Does. Not. Happen!
Ns04
If you don't need an FMIC, dont bother, as they are a faff to fit, but if you do need one, don't let innuendo about massive increases in lag put you off. With a quality FMIC, the right supporting bits and a good map: It. Does. Not. Happen!
Ns04
I have no axe to grind here - in my Newage, I went from TMIC to FMIC (one of Harvey's) then back to TMIC because the (slightly) reduced throttle response for me detracted from the overall driving experience. It wasn't cheap to revert back so I wouldn't have done it unless it bothered me.
And for those who claim it was just because it 'wasn't mapped properly', perhaps worth adding that it was mapped by Andy Forrest, Bob Rawle and Paul at Zen, and that Bob Rawle told me that the reduced throttle response I was experiencing 'couldn't be mapped out and was simply due to the laws of physics'.
Using an MD321H, I consequently ran over 400bhp on a TMIC mapped by Paul Blamire during which the engine clocked up 60,000 trouble-free miles. When I sold the old girl at 92,000, she was still running as sweet as a nut. Yes, I know I could have had an extra few ponies with a FMIC and had I been tracking the car, I would have gone this route. However, for me, the driving experience on the road was ultimately more important than maximising horsepower.
28 February 2011, 04:28 PM
#35
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Some good points here (as always by NS04). However, I would argue that if it is noticeable enough to detract from the overall driving experience, then a reduced throttle response IS significant.
I have no axe to grind here - in my Newage, I went from TMIC to FMIC (one of Harvey's) then back to TMIC because the (slightly) reduced throttle response for me detracted from the overall driving experience. It wasn't cheap to revert back so I wouldn't have done it unless it bothered me.
And for those who claim it was just because it 'wasn't mapped properly', perhaps worth adding that it was mapped by Andy Forrest, Bob Rawle and Paul at Zen, and that Bob Rawle told me that the reduced throttle response I was experiencing 'couldn't be mapped out and was simply due to the laws of physics'.
Using an MD321H, I consequently ran over 400bhp on a TMIC mapped by Paul Blamire during which the engine clocked up 60,000 trouble-free miles. When I sold the old girl at 92,000, she was still running as sweet as a nut. Yes, I know I could have had an extra few ponies with a FMIC and had I been tracking the car, I would have gone this route. However, for me, the driving experience on the road was ultimately more important than maximising horsepower.
I have no axe to grind here - in my Newage, I went from TMIC to FMIC (one of Harvey's) then back to TMIC because the (slightly) reduced throttle response for me detracted from the overall driving experience. It wasn't cheap to revert back so I wouldn't have done it unless it bothered me.
And for those who claim it was just because it 'wasn't mapped properly', perhaps worth adding that it was mapped by Andy Forrest, Bob Rawle and Paul at Zen, and that Bob Rawle told me that the reduced throttle response I was experiencing 'couldn't be mapped out and was simply due to the laws of physics'.
Using an MD321H, I consequently ran over 400bhp on a TMIC mapped by Paul Blamire during which the engine clocked up 60,000 trouble-free miles. When I sold the old girl at 92,000, she was still running as sweet as a nut. Yes, I know I could have had an extra few ponies with a FMIC and had I been tracking the car, I would have gone this route. However, for me, the driving experience on the road was ultimately more important than maximising horsepower.
I wondered when you'd pop up!
Funny enough I had you in mind when I composed that message! You're the only person I know who reported a detriment to driveability when doing the TMIC FMIC swap. There's exception that proves the rule I guess! I seem to recall you having a history with N/A cars? Some cars e.g. an M3 have such good throttle responses that it feels like they'll have your foot off when you prod the throttle compared to a turbo'd scoob, so I guess it's possible to be sensitised to throtle response if you've been spoiled in the past. Interestingly, on the classic I did a very crude experiment with the AVCR I was running. Before and after the FMIC fitment: 3500 rpm and then record time delay between application of WOT and full boost. I put the videos back to back and if there was a difference, it was tiny .... Unfortunately, my blasted old mobile phone on which I recorded the evidence died a death!
I do wonder if the objective difference in your car was as great as the subjective difference, BUT that said: it's what the person who drives the car thinks about it that matters most!
I found that the FMIC made such a positive difference to the way my classic came on boost, that I never looked back!
Just a thought, did you stick with a DV when you went to FMIC. I've run without one on both occassions, and some people - including Bob, IIRC - said that this might be beneficial to spool between gearchanges? Could this be the reason for our discrepant experiences?
Ns04
Last edited by New_scooby_04; 28 February 2011 at 04:30 PM.
28 February 2011, 04:40 PM
#36
Hi Matey
Yep, I think you've hit the nail on the head there - I have run a few NA cars, a couple using individual throttle bodies, which tend to give a lightening response. This means I'm probably overly sensitive (read ****
) about throttle response. I've sold the old girl now though and gone back to NA - Jap import FD2 Civic 
I did end up running with no dump valve and it did help a little bit, albeit at the expense of slightly jerky part throttle on boost (really needs a MAP sensor to sort that). Had I run a Classic, deffo would have used a FMIC. Like you say, I think there's a huge subjective factor about how a car feels to drive ( what a boring world it'd be if we all liked the same!) and I guess people need to experiment for themselves.
Are you running big power now? Seem to remember you had plans...
Yep, I think you've hit the nail on the head there - I have run a few NA cars, a couple using individual throttle bodies, which tend to give a lightening response. This means I'm probably overly sensitive (read ****
) about throttle response. I've sold the old girl now though and gone back to NA - Jap import FD2 Civic I did end up running with no dump valve and it did help a little bit, albeit at the expense of slightly jerky part throttle on boost (really needs a MAP sensor to sort that). Had I run a Classic, deffo would have used a FMIC. Like you say, I think there's a huge subjective factor about how a car feels to drive ( what a boring world it'd be if we all liked the same!) and I guess people need to experiment for themselves.
Are you running big power now? Seem to remember you had plans...
28 February 2011, 07:13 PM
#44
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Hi Matey
Yep, I think you've hit the nail on the head there - I have run a few NA cars, a couple using individual throttle bodies, which tend to give a lightening response. This means I'm probably overly sensitive (read **** ) about throttle response. I've sold the old girl now though and gone back to NA - Jap import FD2 Civic
I did end up running with no dump valve and it did help a little bit, albeit at the expense of slightly jerky part throttle on boost (really needs a MAP sensor to sort that). Had I run a Classic, deffo would have used a FMIC. Like you say, I think there's a huge subjective factor about how a car feels to drive ( what a boring world it'd be if we all liked the same!) and I guess people need to experiment for themselves.
Are you running big power now? Seem to remember you had plans...
Yep, I think you've hit the nail on the head there - I have run a few NA cars, a couple using individual throttle bodies, which tend to give a lightening response. This means I'm probably overly sensitive (read ****
) about throttle response. I've sold the old girl now though and gone back to NA - Jap import FD2 Civic I did end up running with no dump valve and it did help a little bit, albeit at the expense of slightly jerky part throttle on boost (really needs a MAP sensor to sort that). Had I run a Classic, deffo would have used a FMIC. Like you say, I think there's a huge subjective factor about how a car feels to drive ( what a boring world it'd be if we all liked the same!) and I guess people need to experiment for themselves.
Are you running big power now? Seem to remember you had plans...
I do indeed have a big (ish) power build now, yes. It's a forged 2.5 engine from APi with an SC46 turbo. It's billed as a 450/450 conversion, but they tend to produce more like 460/480 with the right set it (which hopefully I have). I'm running it in at the moment, will let you know what it's like when it's had then final map
Oh, you have a VTEC car.... no problem with throttle response on those babies!
28 February 2011, 07:26 PM
#46
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