RB25 Turbo Upgrade

[716RB]

I have been doing some research for a few months now regarding the upgraded turbo setup I want to put on my rb25 series 1 swapped s13. I think I have pretty much come up with a finalized list of pieces necessary for the build and just wanted to post and see if there were any necessary components I have missed or possibly small items I overlooked because I am still relatively new to these engines.
The list is as folows:
-Raw Brokerage 450 hp Billet Turbo with Upgraded High Flow IWG
-Nismo/Jecs 720cc Injectors (Already Purchased)
-AEM Series 2 ECU
-Deatschwerks DW 300 Fuel Pump

These are the items I have finalized. Also looking to do some poncams but thinking that'll be after the initial setup is finished. What I am unsure of is what minor work to be done. The engine has roughly 60k on it and I will be changing the exhaust and intake manifold gaskets in the process. I have read that the stock head gasket can handle high power and have also read it cannot so any insight is helpful. I am looking to reach between 400 and 450 hp and run 20 psi of boost. I already have the Greddy Intake manifold as well. The turbo will be used on the stock exhaust manifold.

[outlaw7]

Although I can't give you any solid proof that I personally have achieved, the miles of pages I've read all seem to say that 450hp is peanuts for a stock rb25 engine, but going much higher and at higher rpm is when things start to get near their limit. Of course tuning is everything. You might consider upgrading the FPR if it hasnt been done yet as well.

[716RB]

I know it is a reachable goal I am just unsure of small things like the FPR you had just mentioned. I am just trying to avoid installing the Turbo, ECU, fuel pump and Injectors and go to get it tuned and have something s*** the bed because I didn't know about something small.

[Darius]

You probably won't need a new FPR unless the stock unit runs too high of fuel pressure at idle and you can't lean it out enough. I ran my stock FPR on 420 whp for a couple years and never had an issue.

One thing that WILL s*** the bed is the ignition system. Plan on replacing the coils with LS2 coils and get that headache out of the way before you get it on the dyno and you can't push the boost past 15 psi because it starts misfiring due to weak stock coils that are nearly 20 years old.

[716RB]

Alright awesome, thanks. So LS2 are the way to go? Most of what I have read about mentioned spitfire coils.

[ben h]

definitly go ls2 coil packs way cheaper then spit fires and put out more spark power and there only 210$ shiped for 8 with wireharness
http://www.ebay.com/itm/OEM-IGNITION-CO ... 60&vxp=mtr

[716RB]

Would my goals be fine on stock MAF setup or would I have to go MAP?

[Darius]

Would my goals be fine on stock MAF setup or would I have to go MAP?

With a Z32 MAF, I believe many people were pushing 500+ whp. I was running about 420 whp on mine and it still had capacity left, so I'd believe it.

[716RB]

Yeah that seems to be the general answer I have come across. Now I plan on getting the AEM wideband sensor and gauge to help increase engine safety but is it completely necessary for tuning and such to get an IAT sensor?

[Darius]

Good question. Some guys run air temp sensors and others run into tuning issues with them. I personally like having that input and haven't had trouble with tuning so I keep it enabled.

[716RB]

I could always add one post-tune correct? Since it merely monitors intake temps it shouldn't be an issue I wouldn't think?

[Darius]

Honestly, an air temp sensor is like $20 from O'Reilly's, so I would recommend installing one. I drilled and tapped the charge piping directly, followed by some RTV sealant on the threads, and it has held nearly 40 psi of boost.

[716RB]

Oh wow didn't realize you could set one up for that cheap. I was thinking it would be comparable to the AEM UEGO Wideband sensor that I am looking to install since I am going to be using AEM series 2

[Darius]

Nah, it is just a GM air temp sensor. Even the "Haltech" air temp sensors are just a marked up GM sensor. Same thing. You just establish the relationship between voltage and temperature in the AEM software so you could really throw any sensor in there that you knew the "curve" for.

[716RB]

Ah, most of that confused me a bit seeing as anything electrical hurts my brain. BUT, I will pick up said sensor and find a friend who is good with wiring and such to get it installed. Thanks for the advice.

[chad b.]

I will tell you what I would do, and you can take it for what it is:

I would def. buy a good fpr. An Aeromotive or a Fuel Lab. I personally wouldn't trust a stock fpr running twice the fuel pump to it. I don't think the stock coils will give you any problems. I made 500whp @ 21psi with sock coils with no misfires or blow outs. I did, however, replace them with SplitFires because it allows you to open up the gap on your plugs for better idle. Yes, you can buy LSx coils. What they aren't telling you is the wiring involved and making a bracket/mounting/etc. Yea, the SplitFires cost more, but they are made for your specific engine, direct replacement, and have an excellent track record. Not saying they work better, but they are easier, and look 1000x better in the bay vs a homemade bracket with plug wires. As for the MAF/MAP question: the AEM is made to run a MAP sensor with the help of an IAT. You will need both. The z32 MAF (N62) can monitor enough air to make more power than that turbo you bought could ever produce. You can even get them in aluminum housings for a blow through setup. Just always consider your surroundings. How many tuners close to you not only know the AEM software very well, but are also very knowledgable of the RB and what it wants and needs to start, idle, drive, and make good power? I had a 30-6620 on my car and sold it for an Enthalpy setup. I personally think an AEM standalone is not made for street cars. They're way too complicated and involved. Plus they will not simulate or read narrow band O2. That being said, your car will never start, idle, or drive as good as it would if it were running a stock mapped ecu. This is my opinion based on personal experience. Take it for what it's worth.

[mixeds14]

This guy^^^. I believe the coils are a matter of opinion. U making it sound like its a job to do the wiring when it's super, super easy..yeah u have to choose we're or how to mount them but that's up to u..Which it's not that hard. Just a bit of time and some creativity..
I have mine in the stock location using the stock coil boot ans spring n they work flawlessly.. Even my idle got better in stock form..
Beside ls coils are available any were and in every auto store for cheap vs a split fire if u ever happen to burn one, goog luck buying just one, more like all six so in theory the ls coils would be cheaper the spitfires in the long run..

[716RB]

The person I was planning on having tune my Car works mostly with AEM. I don't think he has much experience with the RB platform but he says he an tune both MAF and MAP and says MAF wouldn't be an issue as long as whichever I runs oils flow enough air. As far as the coils I'll decide when I get there. I don't mind a small project so the LS2 might be an option. I was drawn to AEM because of it's tuning options and capabilities and I feel like anything else would just require much more in additional components but I am probably wrong because I do not know a whole lot about tuning. I appreciate all the advice everyone. Trying to figure all this out isn't easy.

[Darius]

You'll be fine with the AEM. I have a Haltech which is nearly the same thing and the car is very streetable meaning it never stalls or lugs or any of that nonsense. It is key to have a knowledgeable tuner.

[chad b.]

Wow, mixeds14, I never said the SplitFire coils were better in any way than the LSx coils, nor did I say that wiring them up is a "job". I stated the facts. The Splitfires are a direct replacement, whereas the LSx coils require wiring, a bracket made to mount them on, and plug wires. Yes, we're all aware that GM parts are readily available at the local auto parts stores. I just wanted to give the dude a head's up so he'll know what's involved to install the coils. To the OP, if you are dead set on a stand alone, the Haltech Platinum Pro is a way easier ecu to configure, set up, and tune. Those ECUs are engine specific, unlike the AEM, therefor there is way less bs to calibrate and less unneeded options that you will never use. The AEM and Haltech will both require the same sensors to run which are an intake air temp sensor and a MAP sensor. You will also need a boost solenoid if you want to control boost via the ecu. The AEM EMS will require swapping out the trigger disk in the CAS with an AEM disk.

[716RB]

Would a Walboro 255 be sufficient for my application or should I definitely go with the DW 300?

[716RB]

Bump on the Walboro 255 info

[mixeds14]

Y not get the stealth 340(aem). A bit more money but better product n more pump. Just in case u feel like turning up the boost later on, one less thing u have to worry about..

[chad b.]

A Walbro 255hp was good to about 480whp on my car on pump gas with -6 feed and return line. I swapped it out for an Aeromotive stealth 340.

[716RB]

I had just spoken with raw brokerage again regarding the turbo. Previously I was informed by one of the salesman that there was an upgraded internal wastegate available for those looking to run higher boost levels. This most recent conversation informed me that this option is not available, and as far as I am concerned never existed because this different salesman seemed to have never of heard such a thing and informed me that the wastegate would be close to stock specifications. If I were planning on running 20 psi with my greddy manual boost controller would this upgraded turbo work with said wastegate? I feel like everything I had planned may have just come crashing down due to this information.

[TimTurboZ]

I bought a walbro 400 pretty inexpensive. I have a aeromotive fpr. Ls2 coilpacks aswell

[TheRoadShark]

I had just spoken with raw brokerage again regarding the turbo. Previously I was informed by one of the salesman that there was an upgraded internal wastegate available for those looking to run higher boost levels. This most recent conversation informed me that this option is not available, and as far as I am concerned never existed because this different salesman seemed to have never of heard such a thing and informed me that the wastegate would be close to stock specifications. If I were planning on running 20 psi with my greddy manual boost controller would this upgraded turbo work with said wastegate? I feel like everything I had planned may have just come crashing down due to this information.

I think you're over-thinking things. The WG actuator just controls when the WG opens, so as to stop building boost. The OEM RB25 WG is set to 5psi. That just means that the turbo will only build 5psi - UNLESS you connect a boost controller to increase that. Your boost controller is what allows the turbo to build more than 5 psi, up to the max that the turbo can produce. You're fine.

Increasing the spring tension on the WG just increases the minimum boost the turbo can produce - not the maximum (IIRC). Only really necessary if you want your turbo to always spool up to 20psi (or whatever), with no way to reduce it. Boost controller does the same thing, except you can turn it back down, too.

[TimTurboZ]

get a 38mm wg unless you go past what it can take and you have boost creep issues. then sell it and purchase a 44mm wastegate. my 38mm turbonetics wg came with 4 different springs for different psi/bar ratings. i still use a manual boost controller though.

[716RB]

It is an internally gated turbo. That's one of the reasons I am deciding to go with it so that I can avoid modifying my manifold for an external gate.

[TimTurboZ]

They make 35R's internally gated, I'm sure if u look around you can find an internally gated turbo for you power goals.