EVO IXMR

iTrader: (6)

Was in my friends car today and it was tuned for 31 psi arfs 11.3 to 11.2 with no knock counts..We did a part throttle pull today in the after around 2pm and there were no knocks or blinking check engine light has tephra v7..

Tonight we did a part throttle pull again started in 2 nd went to 3rd then 4th and the blinking happened at the top of 4th at 7k is it cause the boost spiked past the 31 psi due to the colder weather it's now at 33 degress compared to the 53 degrees in the afternoon??thanks.

Boosted Tuning

iTrader: (12)

When using V7, use the "MAF IAT WGDC Correction" table to make it so it pulls a lil WGDC in colder weather to prevent spikes.

EVO IXMR

iTrader: (6)

im on s.d..Also im not the tuner..

EVO IXMR

iTrader: (6)

Bump!!

buchnerj

iTrader: (19)

What is your question? The car is going to boost more, as colder air is more dense, thus leading to more being forced in by the turbine and increasing your boost. You should also see the car start to lean out a little in some instances. This is normal.

If it is a problem and you are starting to see more and more of it coming into the winter months, you must compensate in the tune, either upping the fuel in the fuel tables (alt and main maps if using a dual map tune) or lowering the boost (turn the manual knob down if MBC or dial it back with the EBC or ECU boost).

Is the car that is having this problem on Speed Density? If so, the IAT sensor should help compensate for this change in intake air temps. You installed it close to the throttle body, correct?

Earthen

iTrader: (6)

I live in Michigan, so when the cold weather comes, I just drop a pound or two on my controller. That is all you need to do.

Note: Just make sure your car has had time to warm up before you do any pulls.

EVO IXMR

iTrader: (6)

Installed in the middle off the upper pipe first section its between the throttle body and bov..arfs are 11.2 to 11.4 this is only on part throttle should get a bit richer and a full throttle pull correct..They never got lowered after it was on the dyno d.j but the tuner told him to lower it 1 to 3 psi..if the boost was set at 30.5 to 31 on the dyno what would it touch ion the street??

buchnerj

iTrader: (19)

In the middle of the UICP is alright, ideally you want it as close to the TB as possible so it can detect exactly what the intake air temps are as it enters the manifold.

Just drop the boost down a few psi, as stated before, that will solve the problem just fine. Only catch is that if it warms up again (during the day) then you will be running lower boost than you were tuned for and could run a little rich. This is not a problem at all, just giving you a heads up. What boost controller are you using?

Saying that the AFRs are 11.2 to 11.4 at partial throttle are one thing, but as you open up the throttle you are obviously letting more air into the engine. This will lean out the AFRs consistently as you keep accelerating unless you turn the boost source down. Just because you are in the correct AFR range for a partial throttle pull doesn't mean they will be in check in the higher RPM range. That will depend entirely on the tune and fuel tables in the ROM. Do you have a full pull to post, with AFR values? That could really help us tell you wether or not is is really an issue or not.

EVO IXMR

iTrader: (6)

Maybe it was a bit more then part throttle probably half cause the car was all over the road..lol.At the dyno when I was with him the afr's were 11.3 at redline 8,000rpms in 3rd on a 6 spd tranny..The pull he did with me was all the way to 7,700 'and afr's were 11.4 in 3 rd then 11.2 in 4th afs' are spot on it's more on the rich side.

He said he's even seen them 11.0 but he drives the car I don't..Maybe he should drop the boost down 1 psi to 2psi to balance out for the night cause were he lives it's still in the high 60's in the day and at night low 3o's it would be pointless to keep messing with the mbc for 2 psi it's only a 20 whp difference he still making good power..I didn't think it would knock if it spiked 2 psi but I guess he was tuned for 31 max and that would cause it..Also As you go to higher gears it would spike higher due to load the gauge is probably touching 33 in 4th which is a bit much..

buchnerj

iTrader: (19)

You would be surprised what a few psi of boost can do. When a tuner dials in a setup they aim for a consistent AFR range, and if that was on the lean side and you add a few psi of extra boost, and the timing running at peak load, you can knock.

I would just dial it back a psi and leave it.

Good luck

EVO IXMR

iTrader: (6)

[QUOTE=buchnerj;8818909]You would be surprised what a few psi of boost can do. When a tuner dials in a setup they aim for a consistent AFR range, and if that was on the lean side and you add a few psi of extra boost, and the timing running at peak load, you can knock.

I would just dial it back a psi and leave it.

Good luck
[/QUOTE

Thanks for the feedback and help.
That's very true I'm gonna lower it 2 psi for him cause In one month its gonna be in the high 40's then that would be 30 psi in 3rd and maybe the max 31.5 in 4th which is better then 33 in that gear. ..Hows your car doing are you having fun??

FJF

iTrader: (18)

FWIW, my MBC is mounted to the radiator and I don't open the taps until the oil is up to temp. There's little variance in boost pressure due to a change in temperature - ~95-20F. The spring in the MBC (the part whose properties change with cold temp) has a chance to get warm next to the rad.

BEISSEN

iTrader: (31)

Revived forbim having this similar issue but I only spike in 3rd and 4th even with the ebc off it spikes past wastegate which is 18psi. But in 5 th it holds 26-26.2 psi solid.