What's the most boost you've ever...
 

...fed a stock d15b7?

I have a Subaru rbh5 turbo on mine... stock internal wg... up till a week ago I was hitting a solid 7psi on my boost guage, then when I installed my intercooler, I was only getting 5-6 psi... >:( So, I completely closed my ghetto fab boost controller.

2 x (the boost you're used to) = fun

The boost guage went past 13 psi before I got scared, and got off it. Did this a few times, no ill effects. It should be noted that I have a wideband and made sure my afrs were okay during this ordeal. When I looked at my wb log, I noticed that the voltage from my map sensor climed steadily to 4.8v, then leveled off; indicating I had reached the limits of my map sensor. :o I can assume the boost kept climbing to an unknown level past that, until I let off the throttle.

How close to the breaking point of this engine am I?

Re:What's the most boost you've ever...
 

Depends...not all engines are the same...I ran 15 psi daily on my D15B2 with the Hack. The engine is still running great...A gurl a sold the car to is riding around with it.
If the voltage of the map is falling off...it probably could be that you might begin to run a bit lean on top...so be carefull..if it gets enough fuel you're ok.
Some engines break at 10 psi some brake at 15-16...There is a lot of variables that can cause that..weather...engine care, load, etc etc...also some engines may have come out of the factory stronger then the other.

Re:What's the most boost you've ever...
 

Oh how true that really is. I work at a Saturn dealership and during our pre-delivery inspections you can tell just by the sound which engines are tighter than others. Even on a road test one car will just rip harder than another straight off the truck. No two engines are ever the same even brand spankin new. I was boosting my D15B7 at 8psi non-intercooled supercharged psi for well over a year and took it to 256,000 miles without a hitch.

Re:What's the most boost you've ever...
 

I ran mine d15 w/ DPFI, non-intercooled with a fmu pretty high. First it was 6psi, then that got old so I turned it up to 9psi, and then 12psi. Once I had a problem with my wastegate and the boost probably got to about 17psi before I let off. I looked at the guage after letting off and it was coming back past 15psi :-\

Re:What's the most boost you've ever...
 

i hit 18psi on my b16 once or twice while in 4th gear cause my MBC vacuume hose broke. no detonation noises at all. i would'nt go past 11psi on a d15 though, i run 11-12psi on my b16, but b15 rods are weaker then the b16s'. you should be ok with 11psi and good fuel management.

Re:What's the most boost you've ever...
 

Like everyone else said engines are hit and miss, the d15 has pencil thin rods even compared to other D rods. I wouldn't push it much over 180whp. I know a guy with a D15 w/ihi rhb5 pushing 10 psi at 160/146 whp/wtrq for over a year.

Re:What's the most boost you've ever...
 

realy good tunning makes a world of difference in how long the engine will last. running a little richer on weaker rodded engines will keep them alive too like running 12/1 afr throughout the rev range.

Re:What's the most boost you've ever...
 

Yeah, i'm solid around 12.0/12.2 in boost (uberdata, 450cc injectors, Zeitronix wbo2)

Re:What's the most boost you've ever...
 

that's some good fuel management you gots der. :P

Re:What's the most boost you've ever...
 

Thats they key to a happy engine. Proper tuning! my high mileage jrsc b7 was tuned with Uberdata, 450's and a techedge wideband.