Troubleshooting boost loss
- Thread starter SuperPete
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High on Ethanol
Just Ain't Care
You are probably looking at the wrong metric for performance. Have you noticed changes in 0-60 times, or seat of the pants feels? Boost is not the best indicator of.....much unless used as a tool when you have an issue with drivability or performance.
On SCT I track primarily lambda, timing, intake temp, and knock. If I use my laptop and HPTuners then I track probably everything.
I'm any case of you have concerns or questions, I'd ask the tuner first. Because you are paying for their knowledge and if it's a locked tune, only they can change it.
On SCT I track primarily lambda, timing, intake temp, and knock. If I use my laptop and HPTuners then I track probably everything.
I'm any case of you have concerns or questions, I'd ask the tuner first. Because you are paying for their knowledge and if it's a locked tune, only they can change it.
I put Boost PSI on my SCT screen and I also log, both show low boost.
I have boost solenoid coming tomorrow, will replace that, tank of fresh gas and log again, probably send that log to GreatHead, to see what they say
I have boost solenoid coming tomorrow, will replace that, tank of fresh gas and log again, probably send that log to GreatHead, to see what they say
High on Ethanol
Just Ain't Care
Are you noticing any drivability or performance difference if you ignore the boost reading? I have actually made quicker 0-60 on less boost because my intake temps were lower. Also when I switched to E30 my boost never spiked as high. But if you actually have a boost leak, then by all means troubleshoot and swap parts as needed. When I datalog for Gearhead, I don't even think the log includes boost. But maybe I'm thinking of a different vendor. At any rate, I'm sure Matt will be of great help.
I am actually planing to go E30, finger on the trigger to buy a pump, missed a killer deal, Extreme DI has 20% off during winter $1400 for a pump, I missed by one day LOL
Anyway, maybe this weekend I buy it and go full bore with it
Anyway, maybe this weekend I buy it and go full bore with it
Yes. But there shouldn't be a loss of performance. Your ecu targets load, not boost. Colder Temps require less psi to achieve the same load. Also when you said 19 psi before I assume you were referring to a transient peak and not real loaded boost
When I first glanced your log the other day it was as a spreadsheet on my phone. I'm no pro, but now that I've opened it in livelink it looks to me that 1) your Turbo Wastegate Percentage was through the roof and 2) your intake temps were really high for winter driving with an upgraded IC (heatsoak maybe?). Dumb question but your air filter is clean, yes? Keep looking for boost leaks or blockages but if everything on the surface is OK then maybe a turbo is puking?
High intake tamps because of the heat soak, you are correct.
Filter not in the very bad shape but needs to be cleaned for sure, I will take care of that this weekend.
I am thinking to do smoke test myself to check for leaks over the weekend and I still thinking boost solenoid is possible issue, I have new one coming tomorrow will swap right away.
Why do you think waist gate is trough the roof, what would cause that?
19psi was peak not loaded boost, you are correct
Filter not in the very bad shape but needs to be cleaned for sure, I will take care of that this weekend.
I am thinking to do smoke test myself to check for leaks over the weekend and I still thinking boost solenoid is possible issue, I have new one coming tomorrow will swap right away.
Why do you think waist gate is trough the roof, what would cause that?
19psi was peak not loaded boost, you are correct
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My comments are based on the fact that my car is bone stock and takes 58%-63% WGDC to achieve a load of 1.6-1.7 (14-15psi). You're at 70%-87% for 1.5-1.6 load (12-15 psi) with upgraded exhaust. I also don't get nearly as much boost trailing off at high rpm as you do, which makes me suspect a weak turbo. But that's just me throwing out a half-educated guess. Environment plays a heavy role and what my car does here in Detroit might not jive with what you should expect in PA, particularly if you're up in the hills.
You're meeting or exceeding target TIP pressures so I don't think the solenoid will solve anything. Well, you were on the Jan 3 anyway. It can't **** you to try replacing it though!
SM105K
Streetlight Grand Prix Champ/ IG @fafomotorsports
He is correct, the upgraded intercooler is on the verge of being to big for the stock turbos.
FiveLeeter918
Ortiz Performance Sales
I don't know that I'd say it's "too big" for the stock turbos, but the added pressure drop is almost too much for them to overcome.
I gained 50hp with it, but it's harder to maintain boost without maxing the wastegate. Commanding 18 psi and when the converter locks it starts to taper off to 14 up top. I bought TurboSmart wastegates to try to hold pressure better but like everything else I have no time to install.
SM105K
Streetlight Grand Prix Champ/ IG @fafomotorsports
Just saying what Matt's has said before.
What intercooler did you go with? and can I get a link to it
ridered74
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luigisho
SHO Member
He got me before I found the link! 
Only specific up-sized one is the Gear Head intercooler. https://www.ghtuning.com/product/2010-2018-sho-flex-performance-intercooler/
Only specific up-sized one is the Gear Head intercooler. https://www.ghtuning.com/product/2010-2018-sho-flex-performance-intercooler/
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