2.4l dohc engine + srt4 Turbo - only 4 psi?

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kd0
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2.4l dohc engine + srt4 Turbo - only 4 psi?

Post by kd0 » Sun May 13, 2012 6:11 am

well i got a 98 dodge neon w/ a 2.4L DOHC engine out of a 96 dodge stratus, but it has the 2003 dodge neon SRT-4 turbo in it (manifold, wastegate, turbine/compressor) it has a walbro fuel pump, and different injectors, but im not sure which. It has an intercooler and a BOV

anyway, it has an aftermarket autometer boost gauge, an AEM air/fuel ratio meter, autometer tach/oil/fuel pressure/pyrometer

problem is, i thought this turbo puts out far more PSI then what im getting

she holds steady at 4-5 psi, which is the waste gate actuator spring if im not mistaken?

don't the SRT-4's boost up to say, 11-14 psi or so? is something missing from this setup that would cause the low boost?

he told me to hook the manual boost controller back up to it, and the most i should run is 8psi with it, but im a little confused about why its at 4psi anyway, or is there something in the actual 2.4L DOHC SRT-4 engine that helps make 11-14psi that this engine doesnt have?

I realize this particular stratus engine probably wouldn't hold up to 14 psi so perhaps that is the reason? Anyway the car seems to run great, a/f ratio is 14.8-15.2 most of the time, so its about neutral, and doesnt go lean under 4psi of boost.

if someone thinks they might know the reason please chime in, if you got experience in turbo applications involving these engines, or the srt-4 stock turbo components

if i could remember how to get ahold of the guy i bought it from i probably would just ask him haha.

i dont know much about this car or the turbos on neons or the srt-4's so before i go playing with a boost controller i just want to get some facts from personal experiences i cant seem to generate from my google searches for this particular issue.

i have included a picture of my engine bay, maybe something is missing?

please ignore the 2nd picture where you see the cheap boost controller, i was trying to figure out how to hook it up - but decided not to go through with it until i learn more. Thank you for any and all help, I appreciate it

kd0
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oops, heres the pictures

Post by kd0 » Sun May 13, 2012 6:11 am

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2drSRT4
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Post by 2drSRT4 » Sun May 13, 2012 10:38 pm

I don't know about how those manual boost controllers work, but what it sounds like, you're complaining about the amount of boost you should boost on a stock 2.4. The NSRT4 boosts more because they have a much better bottom end and have a lower compression. I wouldn't boost over 12 on a stock bottom end that I know is in perfect shape. Most people won't go over 8 psi though. And looking at your manual boost controller tubing, it looks like you have a nipple that isn't connected properly. I don't know if that affects it or anything... I haven't ever messed with a manual boost controller.
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kd0
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Post by kd0 » Sun May 13, 2012 11:53 pm

ah yes, please ignore the boost controller in the 2nd picture, i've decided not to use it

thank you for the prompt and polite reply, so that is why it doesnt boost like a srt-4, well thats good, i dont think this block could take it with its stock internals haha

i hear people tossing around 8psi or so as a good number if your afr is good under boost, at idle mine peaks to a top of 15.2, from around 14.6 or so, hovers in there. i havent checked it under 4psi of boost yet but i suppose 12 or so would be ideal or maybe 11.5?

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Post by srt4eh » Mon May 14, 2012 1:29 pm

I'd feel more comfortable in the 11s for afr. Like they said on neons.org...it's more about torque than psi. Just think 8psi on a srt4 turbo puts down a lot less than 8psi on a 50 trim...
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Post by 2drSRT4 » Mon May 14, 2012 7:26 pm

Like Ed said, for air fuel ratios try to aim for 11s or so. 12s if you've got a really good ignition system like an MSD DIS2 with granetelli wires and plugs gapped right. But for a street driven car, aim for mid 11s for air fuel
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Post by 1genRTturbo » Mon May 14, 2012 8:37 pm

if you have a stock stratus bottom end, dont run more than 8psi. you'll bend rods if you go much more. the manual boost guages work ok, but they are finiky at best. they work on the assumtion that boost signal is fed to it, and they "bleed" off some of the presure so that the return signal to the wga is less than what it should be, allowing your turbo to boost higher. it tricks your wga is what im sayin. and 11's or 12's are your sweet spot for a/f ratio. mine runs just shy of 12's consistently at this point.
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Post by kd0 » Fri May 25, 2012 2:51 am

ah alright then, im not sure what kinda power it would be putting out to the crank even

a stock stratus motor from 96 is suppose to do 150hp i think and like 160tq?

the only modifications this motor has is a intercooler, dsm turbo from a srt4, and it looks like the egr is blocked off, along with nothing but a muffler and big custom exahust piping it looks like, maybe 3 inches, or 2.5? and i cant seem to locate the cat converter??

so under 7 or 8 psi im not sure what it would put out, but im not going to go over 7 psi i dont think to be extra safe, and get a decent boost controller, this ebay one is pretty old it seems, and the vaccume hoses might of been leaking as well since when i first tried it, it jumped up to 10 psi or so. so i quickly let off of it.

I have a manual boost gauge, its an autometer phantom, but this manual boost controller is pretty crummy,

im going to be ordering a GrimmSpeed - look those up, it seems to be a superior manual controller, its a bit pricey though when a fella could build one himself.

kd0
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Post by kd0 » Fri May 25, 2012 2:53 am

kd0 wrote:ah alright then, im not sure what kinda power it would be putting out to the crank even

a stock stratus motor from 96 is suppose to do 150hp i think and like 160tq?

the only modifications this motor has is a intercooler, dsm turbo from a srt4, and it looks like the egr is blocked off, along with nothing but a muffler and big custom exahust piping it looks like, maybe 3 inches, or 2.5? and i cant seem to locate the cat converter??

so under 7 or 8 psi im not sure what it would put out, but im not going to go over 7 psi i dont think to be extra safe, and get a decent boost controller, this ebay one is pretty old it seems, and the vaccume hoses might of been leaking as well since when i first tried it, it jumped up to 10 psi or so. so i quickly let off of it.

I have a manual boost gauge, its an autometer phantom, but this manual boost controller is pretty crummy,

im going to be ordering a GrimmSpeed - look those up, it seems to be a superior manual controller, its a bit pricey though when a fella could build one himself.
fuel pressure is about 24psi at just normal driving, and under throttle it jumps up past 40psi, is this good fuel pressure?

kd0
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Post by kd0 » Fri May 25, 2012 2:56 am

i cant seem to figure out what wheels are on this car either, they have a giant R stamped on the center cap

im also not sure what kinda BOV that is either, it has exit points all the way around it, like one big piston just releases it, theres no type R or anything i can see on it, ya know how some of those type R or greddy ones have kind of a horn lookin cone on em haha

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Post by srt4eh » Fri May 25, 2012 10:56 pm

looks like a Tial BOV and it's not a dsm turbo from a srt...it's just a srt turbo
98 Neon R/T, 00 Neon, 06 Jeep GC SRT-8
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Post by 2drSRT4 » Tue May 29, 2012 11:35 pm

Ed is right, does look like a Tial. I like that style. And Ed is right again, it's a factory SRT4 turbo
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