Losing boost at high rpm

[ahl395]

Good news is I'm not loosing boost anymore. On the boost controller there's a setting called boost correction factor. It eliminates boost in high rpm. Is was off I turned it on. Fixed the boost lost. I made two pulls about 5 min from each other and the car made boost pretty quickly. Then the third time I did a pull It was making boost but not as fast as it was making boost on the first couple of hits. Is the car pulling timing when that happens? If so why? Here's some videos

Interesting. That looks much better.

I still say your regular settings are out of whack though. Boost correction is used for when turbo systems boost starts falling off. Centri superchargers do not have this problem, as they build more boost with more RPM. In other words, I'm fairly certain you're fixing a problem you shouldnt have, which is being caused by your other settings. In any case though, it does look significantly better as is.

What are your boost correction settings? It goes by RPM which is typically not even hooked up. What did you use for start/end RPM? Or did you simply just turn it on? Here's the page on boost correction settings.

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[robmustang201528]

Interesting. That looks much better.

I still say your regular settings are out of whack though. Boost correction is used for when turbo systems boost starts falling off. Centri superchargers do not have this problem, as they build more boost with more RPM. In other words, I'm fairly certain you're fixing a problem you shouldnt have, which is being caused by your other settings. In any case though, it does look significantly better as is.


What are your boost correction settings? It goes by RPM which is typically not even hooked up. What did you use for start/end RPM? Or did you simply just turn it on? Here's the page on

Interesting. That looks much better.

I still say your regular settings are out of whack though. Boost correction is used for when turbo systems boost starts falling off. Centri superchargers do not have this problem, as they build more boost with more RPM. In other words, I'm fairly certain you're fixing a problem you shouldnt have, which is being caused by your other settings. In any case though, it does look significantly better as is.

What are your boost correction settings? It goes by RPM which is typically not even hooked up. What did you use for start/end RPM? Or did you simply just turn it on? Here's the page on boost correction settings.

Yeah it's getting there but your right, it still needs some adjusting. Diffrent car, tune and intake I can't expect his setting to work with my setup. Its weird because all I did was turn the boost correction on. It was off. I wanted to see if it was coincidence so I keep making 3rd gear pulls lastnight but I noticed after the 3rd pull, the boost wasn't climbing as fast. Felt like it took for ever to get to 10 pounds in 5th gear vs the first and second pulls I made the car was getting up there quick I'm trying to figure that problem out?.I'm gonna keep playing with it a little. I'm going start playing with the gate and the other settings.

 

[robmustang201528]

Did u look at both videos? First video boost was climbing quickly but by the 3rd pull boost started to climb slowly in 4th and 5th gear. @ahl395

 

[ahl395]

Boost will always build slower in higher gears. RPM rising slower = boost rising slower.

 

[jhatley7]

Did u look at both videos? First video boost was climbing quickly but by the 3rd pull boost started to climb slowly in 4th and 5th gear. @ahl395

Centri’s are not like turbo. Boost is a direct reflection of rpm with load. Being gated does help bring boost in earlier once you get it setup properly.

 

[robmustang201528]

Interesting. That looks much better.

I still say your regular settings are out of whack though. Boost correction is used for when turbo systems boost starts falling off. Centri superchargers do not have this problem, as they build more boost with more RPM. In other words, I'm fairly certain you're fixing a problem you shouldnt have, which is being caused by your other settings. In any case though, it does look significantly better as is.

What are your boost correction settings? It goes by RPM which is typically not even hooked up. What did you use for start/end RPM? Or did you simply just turn it on? Here's the page on boost correction settings.

Interesting. That looks much better.

I still say your regular settings are out of whack though. Boost correction is used for when turbo systems boost starts falling off. Centri superchargers do not have this problem, as they build more boost with more RPM. In other words, I'm fairly certain you're fixing a problem you shouldnt have, which is being caused by your other settings. In any case though, it does look significantly better as is.

What are your boost correction settings? It goes by RPM which is typically not even hooked up. What did you use for start/end RPM? Or did you simply just turn it on? Here's the page on boost correction settings.

You were right... its still loosing boost at high rpm. I think the adjustment I made helped but long story short, I'm taking it to a tuner in a couple of weeks for him to make the proper adjustments and give me 12lbs

 

[gimmie11s]

Belt slip.

Pull blower and inspect behind blower pulley.

 

[robmustang201528]

Got damn it I hope not. I have the 8 rib setup

 

[robmustang201528]

I gonna play around with it tonight. I recorded a couple videos of me doing a pull to 6500rpm and it hit 10lbs and didn't loose boost but once I go past 7000 boost drops

 

[gimmie11s]

Ah.... Yeah 8 rib shouldnt be slipping. This is a wastegated set up right?

As a test, why not bypass the WG completely and run x pulley that is known to give x boost.

 

[robmustang201528]

Yes wastegated. I was thinking about that. I was also thinking about turning the boost controller off and let the spring in the wasgate do the work. I'm just not sure what spring is in there. Pi did a couple 3rd gear pulls in it lastnight. It'll hold boost up until 65 6700 rpm then it'll wasgate the boost out pass 7000

 

[Tommy V]

Well it sounds like your wastegate is letting your boost drop depending on what spring your running.Turbo systems they use co2 to hold the wastegate closed after spring pressure is reached.

 

[ahl395]

Yes wastegated. I was thinking about that. I was also thinking about turning the boost controller off and let the spring in the wasgate do the work. I'm just not sure what spring is in there. Pi did a couple 3rd gear pulls in it lastnight. It'll hold boost up until 65 6700 rpm then it'll wasgate the boost out pass 7000

The wastegate spring is too light. I'm pretty sure I've already told you but you either need a heavier spring or a 4 port solenoid boost controller. You wont fix the problem until one of those happen.

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