Spike with Greddy Profec II

[Drumfreak]

Just installed the Greddy Profec II EBC last night which was a breeze. Now comes the tuning. I figured out what all the functions do in theory but don't know quite yet how to fine tune them. I have the warning set at 10 psi and the limiter set to reduce by 20% It still spiked to a peak of 11.8 psi at one point today. The gain was set to 8 and the start boost was at zero. With the gain all the way down it still spikes, but when the gain is all the way down the boost goes from 7 to 9 psi in 3rd gear. When the gain is at 10 the boost in more consistent. I thought installing this unit would get rid of the spike. It's less than before but still problematic. Does the limiter not stop the spike in time? Whats the best way to start tuning this unit? I know it takes some time but I would appreciate some advice. I should mention that I do have the ATP 6psi WGA and this can't help with my spike situation.

 

[Drumfreak]

Bump. I know this is a pretty technical question/post but please help, thanks.

 

[mspHtown]

http://www.msprotege.com/forum/showthread.php?t=123664225

 

[GhostMercury]

thats alot of work

 

[Drumfreak]

http://www.msprotege.com/forum/showthread.php?t=123664225

Thanks for searching for me.

 

[Drumfreak]

I have the limiter set at 10 psi and set to drop by the max % possible and when in the PSI setting it's 20% but I still spiked to 11.8 yesterday. The only function I havent touched is the start boost. It's set at zero but why increase it since that will cause more spike. Does the limiter even do anything?

 

[mspHtown]

mine does the same damn thing. allows it to go past the limited value i set. i also have spiking issues.

 

[Ryoga28]

You'll want the start boost set roughly where the stock boost is (not the spike). Also for the "set", you want to calculate it based on your stock boost and your desired boost level. For example your stock boost is 7psi and you want 10psi, the the calculation would be (10-7)/10 multiplied by 100 to get the percent.

Now you want to adjust the "set gain" starting from 5 and increasing by 5 if the boost keeps climbing after your desired boost level. For example, you hit 10 psi on 4th gear and is steady but slowly increases to 10.5 or so.

As for the limit you want to set it to +1 of your desired boost. So if you wanted 10 psi, it should be at around 11psi. And the percent should be 4%

 

[Ryoga28]

mine does the same damn thing. allows it to go past the limited value i set. i also have spiking issues.

It's somewhat normal to get a +1 spike on the greddy ebc because that's how the stock msp is. Keep in mind that the Greddy EBC is a bit more sensitive in recording boost that the standard non digital gauges out there.

 

[Drumfreak]

It's somewhat normal to get a +1 spike on the greddy ebc because that's how the stock msp is. Keep in mind that the Greddy EBC is a bit more sensitive in recording boost that the standard non digital gauges out there.

It does seem more sensitive. I have my old boost gauge still hooked up and it will stop at around while the Greddy will register around 11.

 

[Drumfreak]

You'll want the start boost set roughly where the stock boost is (not the spike). Also for the "set", you want to calculate it based on your stock boost and your desired boost level. For example your stock boost is 7psi and you want 10psi, the the calculation would be (10-7)/10 multiplied by 100 to get the percent.

Now you want to adjust the "set gain" starting from 5 and increasing by 5 if the boost keeps climbing after your desired boost level. For example, you hit 10 psi on 4th gear and is steady but slowly increases to 10.5 or so.

As for the limit you want to set it to +1 of your desired boost. So if you wanted 10 psi, it should be at around 11psi. And the percent should be 4%

So do I want to leave the START BOOST setting at zero or should I try raising it?

 

[GhostMercury]

from what i read put it at stock boost. but i could totally be wrong

 

[Boosted03MSP]

This si why i stay away from EBCs. Still get spike just like a MBC> I have a dual stage TurboXS MBC and get little to no spike(less than 1psi) . Hope someone can help you tune it.

 

[Drumfreak]

This si why i stay away from EBCs. Still get spike just like a MBC> I have a dual stage TurboXS MBC and get little to no spike(less than 1psi) . Hope someone can help you tune it.

I essentially paid 300 bucks to not have to stop, open my hood, and turn a dial. Instead I can just press a button while driving. That's my opinion so far but hopefully this thing proves itself worthy. I at one point had the turbo XS dual stage mbc and it spiked to 11 or more just to see 7.5 psi.

 

[geomatics_tech]

my start boost is at 25 (2.5 psi) this will smooth the transition into boost a lot, try raising the start boost to limit the spike.

 

[Ryoga28]

my settings for 10psi is 25%; start boost 70; set gain 35; limit 11.5; limit % 4.

Holds steady at 10 psi and spikes to 11.5psi.

 

[Scott]

I had very similar problems when I had a Profec II spec B. It spiked to frightening proportions. Had it set to 10psi, and it usually only spiked to 11 or 12. So then I turned it down to 8psi, and it spiked to 9-10...until one day the car kicked back hard. I glanced down at the unit, and to my amazement, I saw a 17.8psi peak.

I don't know what was more shocking...seeing that number, or wondering how my engine didn't pop. It was at that point that I wrote off Greddy electronics.

 

[Ryoga28]

I had very similar problems when I had a Profec II spec B. It spiked to frightening proportions. Had it set to 10psi, and it usually only spiked to 11 or 12. So then I turned it down to 8psi, and it spiked to 9-10...until one day the car kicked back hard. I glanced down at the unit, and to my amazement, I saw a 17.8psi peak.

I don't know what was more shocking...seeing that number, or wondering how my engine didn't pop. It was at that point that I wrote off Greddy electronics.

17.8 peak....Is your actuator working? A +1 spike over the desired psi is normal even on a MBC. If you hook up a MBC and have the greddy ebc reading the boost, it'll probably have similar results.

 

[Scott]

My actuator was replaced after I returned the engine to stock.

 

[Drumfreak]

my start boost is at 25 (2.5 psi) this will smooth the transition into boost a lot, try raising the start boost to limit the spike.

I did that and it does limit the boost. I just figured better boost response would equal more spikeso I left that setting at zero. I have the START BOOST at 10 and it barely spikes to 10 psi so I'm starting to feel good about this unit. I still need to go driving and do some tuning though.