5AT Boost Creeping up from 7psi to 9+psi under 3rd to 4'th shift
 

I have a 5AT running a ST setup and My boost holds steady for the most part until i do the 3-4 shift at which point it goes up to 9 and sometimes almost 10 psi. I am on a stock block so this is scaring me a little. I'm also using a manual boost controller right now. I've read that you can do somethings to the wastegate to help this but most of that has been from people with 6MT's. Do you guys think an Electronic Boost controller would help this? Is this a common characteristic of AT's? And if so is this something I should worry about?

Which single turbo kit are you running?

On my 00' S4 with hybrids, I ran a manual boost controller and had the same problem only my boost increased with every gear. I think an EBC would help keep the boost consistent between each gear.

sorry for the dumb question but what are hybrids? are you running an AT?

higher loads will always cause your boost to go up. Unless you have a boost setting much higher than spring pressure and a EBC to smooth it out. A smaill range in boost is normal. if your boost is too high, you will need to go with a lower spring rate.

nm - post deleted

Hybrids are turbos that uses components from two or more turbos. For instance my stock Audi turbos were K03's and my hybrids were K04/K16's inside the stock housing. So basically instead of K03 wheels I had a K16 compressor wheel and a K04 turbine wheel inside ported stock housings. The Audi was manual but my G is a built 5AT.

so you do think a ebc would help? I know it should fluctuate a little bit but I'm hoping 3psi fluctuation is not normal.

it depends on a few factors such as how well your whole wg system is designed. I would go with a lower psi spring and use a good quality EBC, such as SBC ID to control boost.

good info... I've heard that you can port out the wastegate or something and that will help. Anything to this?

Is this a common characteristic of an automatic transmision? I thought i read that somewhere.

Boost spikes are very common on auto's. A proper WG is usually the solution from my readings in the past. Though thats just what I have read an I am no expert.

You could purchase a HKS EVC 6 with the EasyWriter software and program it to drop boost at a certain speed and throttle position.

Let me know if you need one or help setting it up.

-George
GT Motorsports

how is the apexi unit compared to the hks?

???