thanks

 

I'm bringing this topic back from the dead.

Has anyone actually tried switching compressor housing to the anit-surge one on their 35r? If so has it helped the situation at all?

I'm getting major surge in 5th, 4th and a little bit in 3rd at only 19psi on my stock block gt35r w/.63 exhaust housing and the precision 'bullet' sytle proted compressor housing. Its to the point where I can't even smash the gas @ 4k RPM in 4th without getting surge. In fact the only time it doesn't surge during WOT is when I do a drag pass from 1st-4th and thats just because I'm only below 5.5k RPM once in first gear.

 

I'm running a GT40R in my other car.
Considering welding the surge housing shut for better spool.

And I will be running 2 BOV's. One at the compressor exit and one after the intercooler before the throttle body to take care of any surge issues.

I may also stagger the springs inside the BOV's to make one open easier than another. Needs experimentation.

 

For the majority of us with the same turbo, there is no situation. As to why you are experiencing surge, there is almost certainly another reason or issue to be addressed. If you haven't already done so, I might suggest consulting Precision in order to find just what differs with their ported housing. Also, which cams are you using and how are they set?



Unnecessary - a needless expense, begging to be a nightmare.

 

I'm running stock cams. I have 280's sitting on the shelf but I'm not ready to install them yet.

Don't really know why my precision turbo would be different then others. Are you running the same turbo? what is your surge like? I don't think there is anything wrong with my setup, just that is spools much faster then other 2.0ls. See the GT35r spool up thread for more details.

 

There is one potentially aggravating factor right there. The 280s will do far better in your engine than sitting on a shelf.


I am running the same turbo (less ported housing), and I have no surge anywhere.



And that is the major aggravating factor. If it spools too quickly, it will surge regardless of what you do. As for why it may spool too quickly, the first thing I'd address is the tuning. If the ignition timing is too far retarded, it will spool very quickly. Aside from surge, the downside to this is extremely high EGT, which will eventually take its toll on the exhaust valves, manifold, and turbo. What method of tuning are you using and who tuned it?

 

Ok, I reread and now recall the discussion on GT35R spool answers, and I see that you are tuning the car yourself - talking about how fast it spools. Are you retarding the timing as I suspect?

 

no, I'm actually advancing the timing, a lot. I tried dropping the timing back to near what the stock map was and it didn't do squat for helping the surge. All it did was make the car slower, spool didn't really change much.

 

Ok.

When you install the larger cams, you should see a reduction in spool time, a reduction in surging issues, and more power.

Git-R-Done

 

Are you absolutely positive it's surge and not diverter valve/blowoff flutter?

 

I figured the 280s would shift the VE more to right side of the map and help out down low. I just wanted to run mid 11's the way the car is before I go and add more power up top.

so your on a stock 2.0 block, with the exception of cams and headstuds and you have ZERO surge, even in 5th gear on the highway.

 

yes. originally I thought that what it was because I was hearing the BOV flutter when it happened but then I realized the pressure wave would be going back and forth in the charge piping making the BOV flutter.

 

but I like my spool time the way it is and I don't want more power... yet. whhhaaaa

 

Correct, i get this on my car when im in 5th or 6th gear at a low rpm.

 

That is correct - no surge whatsoever, no BOV flutter either.


Shaddup and do it.