hey crew, just wondering... I put in my new turbo at the shop the other day, hooked everything up took it for a burn, wow what a freakin difference, its nutty fast again! The turbo i put in has a ported wastegate with a bigger flapper... Only problem is that the turbo does not spool up until about 4200 RPM.. could the wastegate be too big? I tried adjusting the boost controller a bit, but i know the stock turbo should be making alot more boost lower in the RPM... and this is only with a 2.5 inch downpipe!

Is my MBC screwed? Do i have it hooked up wrong?

MBC is hooked up as follows

vacumn line from the compressor side to the MBC and then from the MBC to the wastegate.... any ideas anyone?

Thanks alot!

Evan

 

Does your new flapper cover the entire wg passage? Can the flapper door still wiggle a little like stock the stock flapper to help seal?

Try running the line straight from the compressor housing to the wg actuator and see if the problem is still there.

If it still shows the same symptoms, try leaving the wg line off the actuator and see how fast boost builds but be careful to watch your boost!!

If it still shows the same symptoms you may probably have boost passing through the wg from the flapper not sealing fully.

 

Hey, thanks alot for the reply.. The wastegate flapper does not move, and it does cover the whole passage. Why would it matter if a little bit of exhaust still escaped? shouldn't there be enough exhaust to boost at lower RPM? or would it take over 4000 RPM to make enough to make the exhaust wheel move... engine is heavily ported too.. I will do those tests tomorrow and report

 

It's normal.

It makes very little boost in 1st gear, especially messing with an MBC.


-Ted

 

Would you suggest an EBC Ted? Would that make a difference?

evan

 

If you've read my previous threads on EBC, I wholeheartly believe they are superior over MBC's with the exception of costs.

I prefer closed-loop EBC's myself.
The A'PEXi AVC-R is one of my favorites.


-Ted