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Discussion Starter #1
I am wondering how much boost my setup can take without leaning out. I don't have a wideband O2, otherwise I'd find out for myself. Anyone else been down this road before or have a current setup thats similar?

Here's my current setup:
5s chrisk shortblock 9:1 CP pistons
Completely stock gen2 3s head
Gen2 fuel rail/injectors/fpr
Gen2 intake/exhaust manifold
Gen2 USDM ECU
Street Brawler 50trim
Stock intercooler
Stock exhaust
 

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My suggestion is to run it at the minimum boost that your system will allow. That turbo will very very quickly out gun your stock fuel system. Just run it at the wastegate spring until you get proper control!

Hope all is well,
 

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Discussion Starter #3
The wastegate spring is a 10psi spring. Currently it's on the wastegate, and with my stock exhaust and stock intercooler I'm measuring a MAX of 5-6psi at the intake manifold.
 

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baktasht said:
Here's my current setup:
5s chrisk shortblock 9:1 CP pistons
Completely stock gen2 3s head
Gen2 fuel rail/injectors/fpr
Gen2 intake/exhaust manifold
Gen2 USDM ECU
Street Brawler 50trim
Stock intercooler
Stock exhaust
I don't think I've ever seen such a mismatched setup. Why would you build a stroker bottom end and leave the head stock? You would have done better to run a stock bottom end, with a ported head and cams. Better yet, you could have done all bolt-ons to a stock motor, and been money (and horsepower) ahead. That 50 trim doesn't like stock Ve 3SGTE's. Didn't you also have a 46 trim? I'd put that on in place of the 50.

I'm sure the stock exhaust and intercooler are the reasons for your low boost on the wastegate spring. Didn't I see you post that you are getting a Berk intercooler soon?

If you are on a budget, I'd get a section of 2.5" pipe welded in place of the stock secondary cat, which will greatly improve your exhaust flow.

To answer your original question, you should be safe at 10PSI on stock fuel. You can probably go beyond 10PSI, but I wouldn't do it without a wideband.

I'd get your setup a little more optimal before I started cranking the boost though. Fix the exhaust and replace the IC, and see if the SB is making closer to it's spring rating without a boost controller helping.

Ken
 

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Discussion Starter #5
Ken,
Well, it was not my plan to be on my current setup. The motor blew and I got laid off, all within a very short period of time. I was on a nemesis, wolfkatz tffr, 850cc injectors, greddy sidemound, and vmax center exit exhaust. Next was going to be cams. I had to sell everything to buy a shortblock. and I was lucky enough to find a chrisk 5s shortblock for a good price (still new, but from the first owner that decided to move away from his mr2 project). So now I'm back up and running, but all my goodies are gone :(

Oh well, life goes on.

I was on a 50trim originally, then moved to a 46trim when I decided to stick with a near stock setup, but then the motor blew and I bought the stroker, so I traded another guy for his 50trim since I knew I'd be doing more modifying and bettering the VE for the bigger turbo later on anyway.

It'll all come back together slowly. It's just not a priority right now like it used to be. For now the majority of my money and time is going into the business.

As for my original question. I was thinking about the same 10PSI that you suggested. I just didn't know for sure and wanted the advice of others who know better. I don't want to push the current setup into unsafe territory until I have the proper setup to do so.

Thanks for the input guys!
 

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As you and Ken both kind of aluded to, why not just take it somewhere and have a quick dyno pull done with AFR to see where you are at? Be sure to sneak up on it by doing a pull or two at light throttle...

My Two Cents...
 

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baktasht said:
Ken,
Well, it was not my plan to be on my current setup. The motor blew and I got laid off, all within a very short period of time.
Ok, that makes a lot more sense now :)

baktasht said:
As for my original question. I was thinking about the same 10PSI that you suggested. I just didn't know for sure and wanted the advice of others who know better. I don't want to push the current setup into unsafe territory until I have the proper setup to do so.
Thanks for the input guys!
Just get it on a dyno with WBO2 and see where you are at.

You're welcome!

Ken
 

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A $50 dyno pull is a lot cheaper than a new motor, as you are now surely aware. I know it seems like dyno/tuning time is getting "nothing" for your money, but after a motor swap, even if it means selling a part off your car to afford it, one dyno pull is worth much more than the actual cost.

Hell, you may even post on your local board and see if somebody has a stand alone wideband (innovate) that they would come let you use for 20 min?
 
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