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Discussion Starter · #1 ·
Hi guys, the most boost I can run on my X is 24/25psi, any more and the boost spikes to 29/30 and goes into limp mode......
This is with a custom map and a perrin 3-port
I've fitted a Gizzmo MS-IBC and have the same problem......
If I connect the boost source direct to the W/G then I get 12psi, but still with a momentary spike to 14/15
Is the normal or do I have a WG/actuator problem?
Cheers, Ken
 

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Discussion Starter · #2 ·
Just checked the WG, perfectly free. With a pressure pump on the actuator it opens around 14psi, doesn't seem to be jerky or sticky. Preload was around 3 turns, took that down to one and the spiking is still there, any ideas?
May have to change the actuator to eliminate this, or is this a problem on the SST's that doesn't manifest itself on a manual car?
 

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Hi guys, the most boost I can run on my X is 24/25psi, any more and the boost spikes to 29/30 and goes into limp mode......
This is with a custom map and a perrin 3-port
I've fitted a Gizzmo MS-IBC and have the same problem......
If I connect the boost source direct to the W/G then I get 12psi, but still with a momentary spike to 14/15
Is the normal or do I have a WG/actuator problem?
Cheers, Ken
Do NOT GO WOT, GO DIRECTLY TO YOU TUNER, I was overboosting with my SST, kinda neglected it, now I'm
Building my engine. I wouldn't even drive it if I were you until it gets fixed. Trust me, any issue is an issue


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Discussion Starter · #5 ·
Cheers guys, but why would it be doing this with a boost controller, surely the tune's out of the loop? What would be the cause?
 

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Cheers guys, but why would it be doing this with a boost controller, surely the tune's out of the loop? What would be the cause?
I'm not sure, but I also had a Perrin 3-port when I was overboosting, not saying that's the cause because im going to run it again once the engines moving again so just because it's a 3-port doesn't mean it won't overboost


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Ken have you tried re-fitting your old 3 port again to see if there is a tune problem or the boost controller? it might need tweeking by a tuner mate?

I dont really understand it either? but my mate also had a tune from Indigo and it went to shit (he wasnt happy), in the end we got Matt over (TRL) last month to sort our cars.

I have to say... I wont be going to anyone else mate.
 

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I got tuned with the Perrin 3-port and the car is set to hit 26 psi. It does this fine in mild/warm weather. My tuner also gave me a cold weather map to use below about 40 degrees F because the car will overboost at cold air temps. Sure enough, the first time I accidentally tested at about 20F the car spiked to 28 psi and I hit a rather sudden throttle cut and ASC light went on (tuner disabled associated codes, so it didn't go full limp).

The cold weather map is set to peak at about 24 psi to make sure there's some error margin.
 

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TBH ive never heard about this weather/density/temp thing?? and never read about it either on the UK forums, but I understand in USA a lot of you guys live in much dryer and hotter conditions than us in europe. Here its never ever dry, so we dont have an issue the really, the air is dense all year round.
 

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TBH ive never heard about this weather/density/temp thing?? and never read about it either on the UK forums, but I understand in USA a lot of you guys live in much dryer and hotter conditions than us in europe. Here its never ever dry, so we dont have an issue the really, the air is dense all year round.
Well when you get tuned at 90F in the summer and then it's 20F in the winter it makes a noticeable difference in air density and tends to lead to boost spikes. It would definitely be nice not to need to worry about it, but as long as you take it into account it's not a huge issue.
 

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I got tuned with the Perrin 3-port and the car is set to hit 26 psi. It does this fine in mild/warm weather. My tuner also gave me a cold weather map to use below about 40 degrees F because the car will overboost at cold air temps. Sure enough, the first time I accidentally tested at about 20F the car spiked to 28 psi and I hit a rather sudden throttle cut and ASC light went on (tuner disabled associated codes, so it didn't go full limp).

The cold weather map is set to peak at about 24 psi to make sure there's some error margin.
I think that's what happened to mine. Cold weather, boost spiked in first. Clutches opened up and let's just say I never completed the shift to 2nd


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Just got done ripping my top off, :( head looks decent though. Turbo looks good too, so...what I'm saying is...don't let your boost spike thread turn into an engine build....like mine


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My tuner also gave me a cold weather map to use below about 40 degrees F because the car will overboost at cold air temps.
Folks, if "cold weather" maps involve BWGDC changes only, there's really no need for such a thing any more. Please take a look at RAX Patch. The IAT Adjusted BWGDC patch adds an extra boost control table...



With this, you can adjust your BWGDC by whatever you want, at whichever intake temperature you want. Summer/Winter should then take care of itself.

This IAT adjustment patch is available for most X ROMs (and Ralliart too... soon).

Rich
 

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Discussion Starter · #18 ·
OK, so put the 3-port back on running ECU controlled boost and all rosy again...... All I can think is the EBC controls boost only on duty cycle and tries to bring it all in at once and as the std turbo is so fast-spooling, the boost overshoots before it stabilises. With ECU control, my tuner has "softened" the way the boost comes in to give the trans an easier life and this is why it doesn't spike.
Having said this, I still don't see why the EBC can't control the spike, unless the WG actuator is sluggish which I will replace this week. I'd really like to have the option of multiple boost settings as the sprint series I compete in over here has a boost limit of 25psi, but I would like to run more on the road.
If I can't get the EBC to work on my car then I'll have to settle for ECU control, just means I can't reach the full potential of my mods if I have to have the tune at 25psi.........
 

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SST cars don't like external boost controllers. Period. One of the easiest way to tell if you should run from your tuner is if he recommends an external boost control method, either manual or electronic for your SST equipped Evo.
 

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Discussion Starter · #20 ·
Trouble is over here I'm only aware of one car fitted with an ebc! I'm a bit of a guinea pig........... His is a Greddy Profec, don't know if they're better than the gizmo?
 
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