I've got to agree with these guys about the "no lag". I could not feel the difference between the stock or a 3.5" ETS intercooler. I definitely felt a power increase.

229hp w/ intake, catback and UICP <--- strangely, didn't gain any from these parts vs. another stock Evo X.
253hp added FMIC <--- no tune

 

You're right that's very general, there are more variables than just "cubic feet" at play. But he does admit that there is more volume to fill, and you need more boost to fill that space with velocity. The irrefutable fact is that it takes additional time to fill that space, no matter how small. When someone goes WOT and says there is no lag just power they are not thinking in terms of overall balance of the low, midrange and throttle response - or drivability. When I put my foot down at any rpm I expect instant feedback, not a moment's hesistation.

 

My car spools as fast or faster than stock so I can confirm what Michael is saying. Sure it might be the combination of parts all flowing more air and being less restrictive that gets me that end result, but very few people are going to take a competely stock car and JUST upgrade the intercooler.

The fact remains that the stock intercooler can and will give you heat soak after repeated runs. Even on a road course where you have higher airflow, the stock intercooler just can't keep the superheated stock turbo air from reducing power as the intake charge gets warmer. People that avoid upgrading their intercooler can continue to do so believing that they are gaining a couple hundred RPM's of spoolup, but don't cry when I pull away from you like you are parked with my GT3076R and FMIC...

Is it the first mod to do to a car? Maybe not, but is it a logical step after doing a full exhaust, intercooler pipes, and increased boost/tune? You bet!

If anyone wants to compare some real world values of Stock turbo spoolup, let's see what RPM people are getting 20 PSI at in 3rd and 4th gear when starting from a 2000 RPM roll. I'll report back tonight after my drive home, I'll need this data when I compare the larger turbo I'm installing.

 

It's always good to see a thread turn the right direction. Thanks everyone for chiming in!

 

Reporting back:

3rd gear = 20 PSI by 3200
4th gear = 20 PSI by 2800

I'll double check again tomorrow in the daylight hours but as soon as I hit 20 PSI I let off the gas and those were the RPM's I was at. I'm thinking the type of turbo is going to have a much larger impact on the spool times but we will see. If those with Dominator 2 and FP Red turbos can chime in, that would be some interesting data points. I'm curious what a bone stock Evo X does in the same situation as well, or someone with similar mods to me minus the FMIC.

 

The poster referenced it very clearly when he attempted to relate to the turbo's measurement .. CFM .. I'll just use the older 16g turbo as reference

14.7psi boost (2bar absolute on the chart) .. in fact when you look at the scale you should already know .. that EVEN a 1 cubic foot increase in volume is going to be negligible increase time taken to fill it up You won't even feel it .. let alone a moment's hesistation

Just to diss Michael from ETS ](because he's not answering my PMs ) Stock FMIC doesn't heat up until the 3rd or 4th run .. it has ALSO a 1.5psi drop in boost

I'm using an ETS 3" core .. so my comparison is with that .. but it will be similiar with many aftermarket FMIC if they are worth their salt..

The temperatures are consistent 20F or so LOWER than stock FMIC (Stock diverge after about 4-5 runs) ..

Boost pressure drop is CONSISTENT 1.5psi drop across the rpm band (versus stock 1.5psi at 2500rpms increasing to 3psi at around 6000rpms)

Keeping everything stock except for the FMIC .. you actually would 'feel' a reduction in lag from the colder charge air alone ..

 

Bigger FMIC = more lag.
I put an AMS FMIC on my Evo VIII and spooled 300rpm later.
Bigger volume core = longer to charge.

Why is this even a debate?

 

Because its a myth and we're trying to debunk it ??

Bigger is volume subjective .. volume measurements in units compared to what a turbo can fill is negligible ..

 

So the $125,000 dyno is a liar, but you have your stuff straight?
300rpm on a 16G is not negligible.

 

I think it's possible that both sides may have a point here, but how many people are going to just install a FMIC upgrade on a totally stock car? I think a well sized upgraded FMIC matched to your power goals is still one of the best investments you can make for consistant power be it street, dyno, strip, or road course use to avoid heat soak. Like I mentioned before, once you have all the other intake and exhaust components opened up to create more HP, any delay caused by increased volume of the intercooler (within reason) should be countered by the denser, colder intake charge reaching the engine. This is especially true if you are raising boost levels above stock, and the stock turbo on the Evo X is known for pumping hot air when pushed to it's limits.

I would love to see some turbo spoolup numbers from those with the stock intercooler as outlined earlier for comparison purposes.

 

Seems like it really depends on the combination of items you have on the car. I hope to get an intercooler to cool things better when car is under stress (tracking).

 

I'll get some numbers in the morning. I have the AMS intake, Nisei upper and lower intercooler pipes, a MBC and a catback on the stock intercooler.

 

OK here ya go...with the stock intercooler and the mods in my sig:

3rd gear = 20 PSI by 3150
4th gear = 20 PSI by 3000

This was after several pulls in each gear, every pull gave me the exact same result. I did the same thing, WOT from a 2000rpm roll, let off at 20psi and immediately look at the tach.

 

I installed an intercooler today and noticed later spool up immediately, hopefully a re-tune can work it out.

 

yeah, you're right!