Fmic Question

[chopobo]

ok I just installed one of GKTECH's cooler kits onto my rb25det series 1

I've noticed the kick is alot harder on boost and I'm loving it

I've also noticed that idle sits about 100rpm higher (maybe resulting in the louder exhaust note on idle)

is this higher idle normal? or should I recheck the cooler pipes incase there is a leak?

cheers

[siddr20]

what is the exact idle?? around 800 mark..

It should be fine with 100rpm more..

Theres also an idle screw behind throttle body which you can adjust if you want to turn down or turn up the idle.

[Faid]

The harder kick on boost is purely because your engine is getting more oxygen to burn, thus out of the same volume of air and fuel in the combustion chamber it can burn more fuel hence make more power. My advise is a good wideband tune to get your AF ratios a 100% this would help a lot

[paulr33]

on standard boost you will gain no power, you will certainly have more throttle lag however

[AdamsR33]

A FMIC doesn't give more power.

[lastlineofdefence]

...just the ability to make more power

[hayai32]

Your idle issue would most likely be from the i/c but if it's only 100rpm it shouldn't be a problem (IMO)... As for performance gains...

I 'felt' like boost came on a little harder when i put a fmic on... Realistically I was probly just expecting/anticipating it would but there probly was no noticible change. A SMALL gain should result though.

However i don't see how lag would increase... The stock cooler/pipes are like 2min noodles (ie restrictive) so a quality fmic shouldn't increase throttle lag... if anything i think it should be equal or better... Might be wrong... Just a thought

[Cubes]

The harder kick on boost is purely because your engine is getting more oxygen to burn, thus out of the same volume of air and fuel in the combustion chamber it can burn more fuel hence make more power. My advise is a good wideband tune to get your AF ratios a 100% this would help a lot

I'd say because it lags slightly more and takes longer to pressurise the void... Then when it does...

[chopobo]

would an safc be enough for tuning afr's?

or do i need something with a better base like powerfc?

[paulr33]

safc is fine and suitable

[Faid]

The SAFC is enough for a safe AF ratio tune. sadly in my country we dont have a dyno. we tune our cars while driving on the airport or smth. but a proper tune on a dyno would be advisable. and a intercooler with bigger piping will increase throttle lag. its simple physics. to create high velocitiy in a small pipe with a pump (read turbo) you need more time to reach the same velocity in a larger pipe with the same pump at the same setting

[mad082]

and it is simple phsics that a fmic will give a little bit more power. it may only be 5hp, but it will be more. the air is cooler, so it will give more power. just because you can't notice it doesn't mean you have gained more power. it takes about a 10hp gain before you will start to notice it.

[Cubes]

mad082, under normal street driving conditions where you only give it a quick squirt through first or second the stock ic holds up .ok. its not until the stock ic becomes heat soaked that the air will be hotter.

The more boost one runs, the quicker the std ic will heatsoak.

[Munna1]

I was running 10psi before the intercooler upgrade and 10psi after and a big difference in power was noticed. Cant comment on the difference it would have made in stock boost though but I tend to agree with mad082's comment.

[cln]

after my fmic was fitted the car now idles near the friction point, anyone know a reason for this?

[fr0st]

and it is simple phsics that a fmic will give a little bit more power. it may only be 5hp, but it will be more. the air is cooler, so it will give more power. just because you can't notice it doesn't mean you have gained more power. it takes about a 10hp gain before you will start to notice it.

When you cool air down it also becomes denser, thus lowering the pressure. Your still cramming the same amount of air in the cylinder as before (higher boost & higher temperature vs lower boost and lower temperature) thats why you shouldn't see a increase in power. The main purpose of the IC to prevent hot inlet temps that you get with higher boost levels so you engine doesn't ping.

The gain is probably the result of putting a less restrictive cooler in, thats just a guess though.

[Cubes]

I was running 10psi before the intercooler upgrade and 10psi after and a big difference in power was noticed. Cant comment on the difference it would have made in stock boost though but I tend to agree with mad082's comment.

I've seen an r33 running 12psi go from 170 something rwkw to a flat 200rwkw just by fitting up the fmic.

You don't pick up that much power from simply cooler air.

[limpus]

Agreed that a fmic doesn't give you alot of extra power...but the cooler air would help slightly...also...being less restrictive than the sh!tty stock smic...you would expect some slight gains...

[Munkyb0y]

on a basically stock R33 rb25det (pod, 3"exhaust, stock boost), would using a R34GTT smic make any difference? Is it a worthwhile upgrade? or is the r33 smic good enough?

i could always go for a front mount, but running stock boost, i dont think it's required, and i dont want the added lag.

[benl1981]

on a basically stock R33 rb25det (pod, 3"exhaust, stock boost), would using a R34GTT smic make any difference? Is it a worthwhile upgrade? or is the r33 smic good enough?

i could always go for a front mount, but running stock boost, i dont think it's required, and i dont want the added lag.

Dont bother if stock boost. I'm running 10psi thorugh a r34 SMIC and it is fine. A FMIC at 10psi or less or even on the stock turbo is a bit of a showy thing rather than a performance gain.

Unless your on boost around a track for hours , then a FMIC might be worth it.