Why does boost keep increasing past what I've set it for?

["Turbo-T"]

Here goes.

I recently installed a powerlogger and set the boost at 24 psi via the RJC boost controller.

When I go WOT boost according to the powerlogger usually goes to 21-22 and as high as 23-24.

However tonight once the trans hit 4th and the converter locked up, according to the powerlogger I managed to get up to 27.5 psi. it was brief but still...it has me worried.

According to my powerlogger, when in boost the psi tends to fluctuate.

Is this normal?

It's a TE-60 turbo with a .63 housing.

Is going to 27.5 some sort of boost spike? Or boost creep?

Any info?

Thanks!

 

[WSLN 6]

When would you ever use 4th gear with the converter locked? You should be using 3rd only on any abusive runs.
What ownpipe/wastegate combo are you using?

 

["Turbo-T"]

Terry Houston internal style. 4th gear/TCC was my foot in it WOT on freeway. I wasn't at the track. Should I let off as soon as it hits 4th?

 

[Boost231]

hold it in 3rd gear. If you have it in OD let out ASAP

 

[jasjamz]

How fast are you going when it hits 4th?

 

[WSLN 6]

You would end up short shifting if you were in OD as well.
I would make sure that your wastegate hole is ported to the maximum size for the puck.
You should not run out of rpm in 3rd with your converter locked unless you are doing over 145mph or so.

 

[jasjamz]

You should not run out of rpm in 3rd with your converter locked unless you are doing over 145mph or so.

Same thing I was thinking, unless it has 4.10s or something

 

["Turbo-T"]

How fast are you going when it hits 4th?

98-99 mph...that's on a 215/65R15 tire....is that about right?

 

[Red C5]

99mph and its shifting to 4th? Seems pretty early. I would think it's boost creep to answer the original question though.

 

["Turbo-T"]

Yes according to my powerlogger files, if I am WOT it will shift into 4th at 98-99 mph, both times the rpms were reading 4875 at the time of the shift.

When should it shift to 4th at WOT?