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E_Jay_Twenty
09-22-2011, 10:49 PM
Hey guys,
I just bought my first 240sx 2 days ago. Its a 1992 SE coupe with a blacktop sr20. I come from the Subaru world over at NASIOC.com, Ive been a subaru guy for the past 5 years and decided I wanted a new toy.
So that being said I'm not all that familiar yet with the sr20. My question how many pounds of boost should I run on this setup-
s13 blacktop sr20
s15 sr turbo
Greddy intake for S15 turbo
Z32 MAF
Greddy VSPL front mount
Apr diverter valve
Walbro 255 LPH fuel pump
Deatschwerks 550cc injectors,
Greddy divorced o2 housing
Rsr downpipe
High Flow cat
Apexi Noir exhaust,
Heres what the seller posted about the setup:
"Tuned ECU For this setup. Max recomended boost is 1.0 - 1.1 KPA with BKR7E plugs."
He said the current plugs in the car should be replaced because they arent the bkr7e's. Then he told me to get those plugs and I'd be good to crank it up to 16 lbs. Im not going to unless I hear some suggestions.
Any suggestions on how many pounds of boost to run? Not sure if I wanna just take his word for it because some people dont know what they are talking about. Id rather have some more insight from other people.
Thanks and if you need any more info Ill try to gather what I can from the seller,
Garret

E_Jay_Twenty
09-22-2011, 10:51 PM
annnnd I think he meant BAR not KPA

DeeezwasRiceSauce
09-22-2011, 10:52 PM
18psi or like 6psi with proper wastegate.. too much for your ecu.. not gona juice your injectors gona drain your battery until your distributor is stripped. max 15psi

E_Jay_Twenty
09-22-2011, 11:04 PM
Im also looking around on the forums, someone posted this:

Preferrably just shoot for low 300whp setup and just run less boost.
550cc
T28 or 18G turbo.
Z32 Maf
Rom Tune ECU

SLiDe_WaYz
09-22-2011, 11:19 PM
12psi is what I would stop at on stock head gasket.

Speaking from experience lol

DeeezwasRiceSauce
09-22-2011, 11:30 PM
Im also looking around on the forums, someone posted this:

Preferrably just shoot for low 300whp setup and just run less boost.
550cc
T28 or 18G turbo.
Z32 Maf
Rom Tune ECU

this is a dry tune you'll make 200hp and like 450 tq.

negrosx13
09-23-2011, 12:10 AM
12-14 is good,its getting colder by the week. So you gonna have little bit creep,but depends on if your running ebc or mbc. Im pushing 13-14ish with mbc and i seen it creep 15 then down back to 13-14psi. just be aware of your gauges

fliprayzin240sx
09-23-2011, 01:44 AM
I'd ask to see if its a mail order rom tune or not. If its mail order, might wanna get it on a dyno to double check the AFR with that tune before I decide to crank up the boost. For the most part, 500cc injectors will be maxing out around 300hp on most setups I've seen. 1 Bar on S15 turbos should yield you about 280 ish.

Anyways, what made you decide to jump from one rod knocking engine to another one?

WaWa
09-23-2011, 03:30 AM
id probably just run 10-12psi MAX with a stock head gasket and bolts.... also i heard alot of things about boost creep on this thread so i will let you know that another thing thatll help it just a lil bit would be to get an o2 housing or dump pipe as people call it... they're about 150 bucks and i know Tomei USA is a good brand and i'll stand by them on that.... hit me up if you have any more questions

E_Jay_Twenty
09-23-2011, 07:54 AM
I was told it had a street tune with this setup

cotbu
09-23-2011, 09:27 AM
The headgasket doesn't have a boost rating on it, so how does it know when to blow?
Why do stock NA engine blow headgaskets?

Tuning is not just a word we use to take your money.

SLiDe_WaYz
09-23-2011, 09:45 AM
id probably just run 10-12psi MAX with a stock head gasket and bolts.... also i heard alot of things about boost creep on this thread so i will let you know that another thing thatll help it just a lil bit would be to get an o2 housing or dump pipe as people call it... they're about 150 bucks and i know Tomei USA is a good brand and i'll stand by them on that.... hit me up if you have any more questions

The Tomei turbo elbow with the dump pipe isn't 150$.... You might want to double that price and then ur around the ballpark for a brand new one.

OkiDori17
09-23-2011, 12:47 PM
How long have you had the car?
If you've just gotten it, I wouldn't try cranking up the boost quite yet.
If you can't trust the guy knowing one thing, how do you know he installed everything correctly. I would drive it around and make sure everything is running right before I'd go for more power.
But 12lbs is around all I would go. The stock head gasket was made to run 6-7lbs (stock), how do you think it'll like doubling that?
If you have the cash try picking up a good head gasket and not only will your engine be safe, but you might learn a thing or two from replacing it.
A BIG thing I've learned from the SR is it's far better to be safe than sorry, being sorry costs too much. =]

WaWa
09-23-2011, 01:57 PM
The Tomei turbo elbow with the dump pipe isn't 150$.... You might want to double that price and then ur around the ballpark for a brand new one.

they're $190 for brand new tomei turbo outlet (elbow pipe, dump pipe, etc.) whatever other names people have for it but here's the link and like i said its around $150 i was 40 bucks off and that was just from memory from when i looked it up for my s15

EXPREME OUTLET PIPE for SR20 (http://www.tomei-p.co.jp/_2003web-catalogue/000_expreme/each-product/sr20_outlet-pipe_en.html)

jr_ss
09-23-2011, 03:26 PM
The stock head gasket was made to run 6-7lbs (stock), how do you think it'll like doubling that?


I drove around for a year and a half with ARP's and a new OEM headgasket at 11-12psi on my T28. The stock headgasket isn't the issue, it's the clamping force. Stock headbolts will not like it, but ARP's with a stock gasket, I wouldn't hesitate to run it.

cotbu
09-23-2011, 06:53 PM
How long have you had the car?
If you've just gotten it, I wouldn't try cranking up the boost quite yet.
If you can't trust the guy knowing one thing, how do you know he installed everything correctly. I would drive it around and make sure everything is running right before I'd go for more power.
But 12lbs is around all I would go. The stock head gasket was made to run 6-7lbs (stock), how do you think it'll like doubling that?
If you have the cash try picking up a good head gasket and not only will your engine be safe, but you might learn a thing or two from replacing it.
A BIG thing I've learned from the SR is it's far better to be safe than sorry, being sorry costs too much. =]

This is funny considering the stock boost on a redtop sr20 is 11psi

I drove around for a year and a half with ARP's and a new OEM headgasket at 11-12psi on my T28. The stock headgasket isn't the issue, it's the clamping force. Stock headbolts will not like it, but ARP's with a stock gasket, I wouldn't hesitate to run it.

So true, but i've only witness lifted heads twice. I do agree head bolts suck.
Studs do get a recommendation.

So as rich a the stock tune gets, I'd only run max of 13psi which is all I could run with my setup, as I was maxing out the mafs voltage, It is not boost specific but more so a flowing issue. Also at the time I raised the base fuel pressure for added security. I also screwed around with the SAFC. So yeah I've been there and done that, Still on the same engine, No rebuild pushing 20psi High boost, and Daily boost is 17psi. Tuned via Nistune. Today it is rainy as hell and I turned the boost controller off. Habit but the gate is set at 14psi so it like 17psi but Not.

The OP's setup should be good for 14psi or even 16psi, but He needs to verify that tune. Take a look and see if it has a daughterboard, dump the bins send them to any tuner that is willing, get them verified or pay for a retune. Your setup is so common I'm willing to bet there.s a shelf tune that will work wonders lol.

PS I had deatschwerks 555cc injectors for like 3-4yrs never leaked but when I upgraded to a GT2871r they flowed 582-585. I was making 350hp. So if those injectors aren't new they should be flowed or replaced.
:lfault:

cotbu
09-23-2011, 06:57 PM
I think I'm ovulating or something.=p