Something I've just realised, FMIC has given the furby a real sense of turbo lag. Was doing some playful drag racing on Sunday, against a Paxo and a mini-moto (see my other thread with vid clip )

Realised that my usual style of quick acceleration wasn't working, as I more or less let the clutch go, and was down at 1500rpm with no clutch to slip and help. The paxo beat me also as I missed 2nd, but I can't blame that on the FMIC.

I've found over the last month or so that to get the best acceleration some serious pre-throttle work is needed before you think about releasing the clutch, We're not talking lots of time, perhaps less than half a second more, but in times of need, its one the things I've noticed which is different.

How is the Forge FMIC affecting lag? I know there's an extra 3 feet perhaps of extra pipework + the intercooler itself. Has it changed much? I do know with mine its got 50mm wide pipework right from the turbo outlet, through the FMIC and right to the inlet manifold, which coupled with the hybrid might exaccerbate(sp? ) the lag symptoms.

Easy to drive around, but I just wondered what others have experienced with the Forge one - and John yardley too I guess, as he's the only one running the same FMIC as me, but with different turbo outlet pipework I suspect.

It's a very interesting point, Jason

After some driving with mine, I've made two observations:

1) The engine sounds different. I'd appreciate Colin's views as well as others who've fitted the Forge FMIC. The sound change is hard to explain. It's almost lost its PD-like sound, sounding more like a generic tdi.

2) The way boost comes in has changed. Yes, there is a bit of lag, and I think Neil at TSR spotted it straight away on the RR - he said he thought something's not right as if the car didn't want to go. Give it some beans and about half a second later, it takes off. In fact, whilst it may have lost some of its punchiness, it's a lot smoother and pulls harder at the top end. A brief test revealed there's no trouble hitting 5k rpm now :eek:

Ohh and a side effect is my clutch is slipping more now than it ever has, so I guess there is more torque than before, but it just takes a fraction longer to build up.

I need a new clutch Any suggestions? (JBS's stuff, Sachs.....) :confused:

[cough] JBS [cough]

Its not bad - shame you never got to try mine out properly on Saturday. Clutch is just so forgiving and just THERE all the time, solid as a rock. (if you know what I mean? )

Edit: And I concur your engine sound change - Especially on boost-up - totally different note from what my ears can tell me (comparing to remapped PD100 which was the last time I ran an SMIC on a PD)

I need an undertray to help sound deaden a bit.

FFS will you two stop whinging!

of course the engine will sound different, the air has to travel a different path, theres not as-much back pressure either...

the lag is because the forge i/c is over twice the capacity of the oe item..(apart from mine ) not sure on pipework tho.

Cant say i have noticed the lag but have only had it fitted since last Thursday, so more testing probably needed.

I have found it is keener to rev and if you blip the throttle during downchanges it is much more responsive and it revs easily to 5k rpm as Xavier said.

On the whole i have found it much more responsive and it feels there is more power and more importantly the power is not lost due to heatsoak. 4th gear acceleration right up to near 5k rpm is pretty impressive now.

Engine noise is perhaps a touch louder and i can hear the turbo whistle a bit more.

IIRC with the Forge FMIC, when tested it only lost 1psi boost over standard, but dont know if this would be a cause of lag.

The lag effect i dont like is from the ASR so I usually switch it off unless it is raining. ASR seems to dull the cars responses.

I'm not whinging - I like it.

Just something I wondered if anyone else had fun adapting to?

Twice the capacity makes sense. Think mine might be 3 times just due to not using any OEM pipework at all.

Ovbiously it will take the turbo a fraction of a second more to reach "terminal boost" pressure due to the extra space it has to fill, but its not noticeable when your over 2500rpm, and only marginal if your under that.

but im glad that people are happy with their fmic... big to forge is in order

I quite like the new engine note since having the fmic fitted. Sounds more like a low level purr. I quite enjoy turning the radio off to listen to the new sound on a long run after listening to the same cd's over and over. I wonder what it's going to sound like when I get the Miltek turbo back exhaust fitted this friday.

Boost gauge ?

Boost gauge ?

I have, yup. And you can't really use that as a guide tothe lag, as it appears to boost up pretty quick and smoothly on the guage - Its just IF I had had a guage on my old setup it would have shown a slightly more instantaneous turbo response to the throttle. We're only talking tenths of a second and after a while I'm going to think "what lag?"