FMIC/TMIC & battling Heatsoak

After switching to a FMIC setup I noticed that the slugishness that I experienced with my Perrin TMIC was still there on the hot days...especially in stop and go or slow (below 30mph) traffic. I tried wrapping the "hotside" of my FMIC pipes in an effor to keep underhood temps down but the problem was still there. In my latest effort to combat this problem I started playing around with the IAT ignition timing compensation tables (essentially reducing the amount of timing pulled based off of IAT) and I have seen/felt some better results.

 

I am wondering what tuning strategies everyone is using to compensate for a larger TMIC or FMIC and their added cooling ability. Since the air temp is being measured at the intake, is there any other IAT compensations I could "reduce" or is blow-through my only option?

Isn't water injection typically the answer for that?

Have you played with the AVCS yet? That makes a big difference in low end throttle response and spool. What turbo are you running?

Stock turbo, I am basically stage 2 with a FMIC. AVCS is definately something I woudl like to play with soon..I didn;t realize it might help performance in the heat...hmmm.

Stock turbo, I am basically stage 2 with a FMIC. AVCS is definately something I woudl like to play with soon..I didn;t realize it might help performance in the heat...hmmm.

It won't help performance in the heat however it will aid spool in turn which would reduce the affects of the higher temps. I generally averaged full boost (18.5psi) between 2500-2700 rpms in 70 degree temps on the stock turbo in 3rd.

Very cool..I am hitting peak about 100-200 rpms later.

 

Any thoughts on changing the timing IAT comp table? My thinking is that since the FMIC does a better job of cooling the air then the stock TMIC, I could relax the pulling of timing called on in the stock compensation map.

 

For instance..the stock comp table has more than 2 degrees of timing pulled at and IAT of 104 and almost 4 degrees of timing pulled at and IAT of 140. For reference my IAT gets to 140 after 2-3 minutes of idling in 60 degree weather.

 

I eliminated all - comp from 104 and cooler and halfed the - comp from 104 up...car feels a little less slugish and no knock.

Very cool..I am hitting peak about 100-200 rpms later.

 

Any thoughts on changing the timing IAT comp table? My thinking is that since the FMIC does a better job of cooling the air then the stock TMIC, I could relax the pulling of timing called on in the stock compensation map.

 

For instance..the stock comp table has more than 2 degrees of timing pulled at and IAT of 104 and almost 4 degrees of timing pulled at and IAT of 140. For reference my IAT gets to 140 after 2-3 minutes of idling in 60 degree weather.

 

I eliminated all - comp from 104 and cooler and halfed the - comp from 104 up...car feels a little less slugish and no knock.

As long as you are monitoring the knock, I personally would never do this. I figure what is the reason, better safe than sorry. The only place I would consider that would be at the track on high octane.

I gotta stop trying to squeeze every ounce of HP out of the stock turbo and just upgrade!

I beat my stock turbo seven ways from Sunday too. You always think there just a little more there somewhere. It's actually a great way to learn how to tune... and even more importantly how not to tune;).

i gotta stop trying to squeeze every ounce of hp out of the stock turbo and just upgrade!

 

+1!

I need to convince the wife that I need a new turbo/injectors/pump on a car with 20K miles..

I need to convince the wife that I need a new turbo/injectors/pump on a car with 20K miles..

 

No such issues here, but I do need to decide between 3 avenues of upgrade.

 

VF-52 and supporting mods

STI swap (someone had most of the parts needed for $900!)

FMIC and completely different big nasty turbo with supporting mods

 

In the meantime, I've been constantly tweaking my map as well to get every last bit or keep every last bit as the temps/humidity rise.

I am liking the new 68HTA turbo....great spool and pretty good top end, somewhere between an 18 and 20G but with awesome spool.

You mentioned you heat wrapped the outlet pipes but did you wrap the cool side piping? Wrap all the piping and you will beat heat soak as much as possible. Remember your piping cooled air back thru a hot engine compartment. I have all of mine insulated and it does make a difference. You could always install a water sprayer on the IC core too, not much help in stop and go but it worked well when I was running a top mount.

Interesting, when I thought about wrapping the hot side, it was to keep the heat in the pipe (and out of the engine). I never thought that wrapping the cool side would have the opposite effect, it will insulate the cool air from the hot engine..makes sense though. I think i have enough wrap to do it too..

With a FMIC I would consider relaxing the timing comp vs IAT table.

 

Myself and Edmundu both relaxed ours in the upper temp range (we also made changes in the lower temp range, different topic) because we were running alky injection.

 

Here is mine right now: (not that I suggest you use it, always monitor your car)

 

http://i248.photobucket.com/albums/gg194/littlebluegt/IATtimingcomptable.jpg

Thanks...I did the same thing..just a little less agressive than you and Edmundo did.

 

I wonder if a turbo blanket is worth the investement?

Thanks...I did the same thing..just a little less agressive than you and Edmundo did.

 

I wonder if a turbo blanket is worth the investement?

 

Maybe. Much easier to do on a turbo w/ EWG, then making it go around a WG actuator and WG and not touching anything.

I know this is an old topic but I was just curious what IAT is too hot? I have the x02 fmic and typhoon intake with the hot side and cold side wrapped in the engine bay and get up to 140 in about 5 minutes or more in the drive through at 40-50 degrees outside. I am going to try to cut the metal shield that came with the intake to try and utilize it as a cold box but was just curious what the general consensus is on when you should be worried.

 

Dave