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Max safe boost? [Merged 10-6]

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Getting ready to up the boost on my car and im just wondering what is a safe level of boost to run without pushing it beyond its limits. Not looking for anything suoer conservative but dont wanna push the limits as well. Ive done all maintainence needed and checked the compression and made sure the motor is sound. Ill be tuning with an SAFC and MTXL wideband as well. Let me know what you guys think, was gearing around 18 - but will go more if i can :)

Mods:
ebay 16g
550's
2g MAF
VSRF Front Mount
2.5 turbo back exhaust
hallman MBC
1g BOV
 
Safe boost levels for what you have on your car would be 18-20 psi. As long as your tuning with your SAFC and WB are accurate you could go up a little more. But for safe boost levels, stay under 20.
 
You need a logger and wide band to find out what a safe boost level to run on your car is. What's good for other people cars might not work for yours.

Ill be tuning with an SAFC and MTXL wideband as well.

Tuning your car is trying to achieve your target AFR and boost level without knock so that's how you will find safe level of boost.
 
I agree you should at least have a wide band. I'm in the same ball park as you right now at least I will be when my 550's get here. But I'm shooting for 18 psi.
 
I'd also agree on getting atleast a wideband before you starting trying to up the boost.

Also I don't see a fuel pump in your list. That will be a restriction even before stock injectors.
 
I have a 1992 GSX 5-spd. Car came with the 13g turbo though. I have a FMIC, MBC, 450's, SRS full 3" exhaust, ported 2g manifold, BPR7ES plugs gapped to .028, and have just done a ton of maintenance to it including a full timing job and adjusting the CAS and TPS properly. Just curious how much psi this turbo is efficient to and what is safe? I had it at 17, and I thought I read it is only efficient to 17.5 or something? Any help would be great. Thanks guys.
 
I'm just curious as to what kinda duty cycle my injectors are seeing? I'd like to keep them below 80%. I have it at 14psi right now. Was gonna bump it to 15, or whatever you guys believe is safe and efficient? Thanks.
 
I dont see a manual ecu or fpr on that list. Maybe u forgot to mention them.

Not having the manual ecu i bet that thing launches like my grandma.

I never got to mod the car with my 13g..That little bastard was fun tho..Pretty sure 70k miles and me learning how to use a boost controller killed that thing real quick.LOL

I always wanted to be a 13g killer gsx.I lost to a crx that did 13s by a fender because i shifted to 4th..ITs not that it cant support 17 psi its really that its not gonna keep that psi untill redline so your power curve comes on strong from 2k to 5k ish and then just drops.
 
Has a manual ecu***

I said I had 450's, that pretty much tells you I have a manual ecu no...?

And, it actually launches like a bat out of hell, even when it was at 9psi haha.
 
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Has a manual ecu***

I said I had 450's, that pretty much tells you I have a manual ecu no...?

And, it actually launches like a bat out of hell, even when it was at 9psi haha.

No i just assumed idiot previous owners didnt mod it right..With the manual ecu it should launch like a bat out of hell.

At least its got the right ecu.Thats one of the first mods i tell people, manual ecu and 450s with the manual fpr.
 
I would do an AFPR, but, I'm in college and I spent a lot of money just taking care of the previous owner's ####-ups and what not. I did all the work with fellow DSM'ers, and it cost me about a grand just to get it reliable (that's just parts cost, b/c labor was free thank the heavens). But, the car is great for now, I know they have their problems. Just don't wanna be pushing the 13g too hard, but, also want to be as fast as I can on that lil' guy. I'll be going bastard 20g this summer, afpr, wally 255.
 


I was there remember..I really loved the 13g at that time.



Another thing to note is that the 5cm turbine housings which come from the factory on DSM 13G's is smaller than the .49 turbine housing on T25's from a manual-trans 2G. The T25, despite a more unreliable thrust system, will actually have more turbine flow than a 13G.

Means the t25 may flow more than the 13g.The t25 is unreliable..Whats it like 330 on a 13g or some shit?
 
Lmao, I plan to be rolling. I did a head gasket on this motor as well, and the compression is 150-155 across the board. Pretty nice if you ask me. I had to do a head gasket b/c my crank trigger plate and my crank sprocket had worn out keyways. No clue how that could've happened. But, I thought I read you can make more hp on a 13g than a t25? I checked the 13g for any play and it is mint. Can you say anything more about a shift box? Thanks again guys.
 
Dont base your tuning off of desired boost, every car is different. a car running 15 psi with solid AFR numbers is a lot more desirable than a car running 16 psi that is running rich or lean with knock.

i would also suggest an aftermarket fuel pump and afpr if you are wanting to really dial in your tune, bigger injectors will only flow what your stock fuel pump and fpr will let them.
 
You need a logger and wide band to find out what a safe boost level to run on your car is. What's good for other people cars might not work for yours.



Tuning your car is trying to achieve your target AFR and boost level without knock so that's how you will find safe level of boost.

I agree with his reply, the safest way to acheive this would be either electronically retard your timing by 10 degrees or so then move closer to base timing from there as you get closer to your desired AFR 14.7 is the proven best AFR for gas mileage, drivability etc. etc.
 
I could go on and on about the shift box, so why dont you pm me about it and ill fill ya in?

Because it would be completely useless since it's a 5 speed. It states it in the first post.

No the turbo cannot support 17psi, it's not in that it can't hold pressure to redline, it's that its out of its efficiency range. Blowing hot air into the intake will make it slower than running lower pressure and keeping intake temps down.

That turbo really isn't meant for much boost.
 
I'd run it around 15 PSI just to be safe, plus be careful not to max out the duty cycle of your inj. aand I'm sure any higher boost would cause the turbo to boost drop at higher RPM'S
 
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