Boost Problems.
 

So as the title states. I currently have a Walbro 255lph fuel pump, 750cc secondary injectors, moved the secondaries into the primaries, FD turbo plugs, BHR ignition, the BNR upgraded greddy turbo kit, AEM tru boost, and Cobb AP. These are my mods that relate to fuel air and spark so here is my problem. I am currently running boost at 10psi, as I boost it feels great but once I reach 6k rpm, the boost seems to drop and everything just starts to feel like crap. I already read in the BNR turbo blog that bryan is making an actuator, and also read a bigger intercooler just wouldnt be practical, so I already checked for boost leaks and changed my silicone couplers, what else could be going on? thanks, any suggestions are a ton of help.

Tune?

The kit is designed for 6ish psi, I assume you're outflowing the effciency of the turbo for this application. I believe a friend of mine had this same problem...

tune? or you need the upgraded actuator?

^This. http://www.mazdamaniac.com/portal/smiles/doobie.gif

Hey Jeff I need a intercooler, can i get your contact of where you get yours or let me know if i can get one through you?..sorry for the thread jack

Are you telling me the tunes OK?

ok well the tuner said he is having problems cause the turbo cant even pass 6k, as far as psi I called greddy and asked them what is the limit and they said 14 psi, 6psi is what the stock wastegate is set at, so I assumed 10psi should be ok. The thread about the BNR turbo bryan keeps saying that the intercooler is the restriction but another thread said the intercooler caused overheating issues so im confused but I have a brand new garrett intercooler.

So if everyone is saying the tune, then I will have to just give it back to the tuners and tell them it's their fault. LOL

hey if anyone is looking for an intercooler i have a garrett 24x10x4 intercooler(measurement is with endtanks) 600hp 900ish cfm

I seriously doubt the stock greddy intercooler would be the restriction, I have run near 2 bar on smaller intercoolers. That intercooler should work just fine on any greddy or greddy hybrid at 10psi.


You mentioned it feels like crap and boost is dropping, doesn't sound like a turbo/intercooler issue... Boost will drop off if the tune is off or there is some sort of other setup issue...

some ideas for you

* tune - would have to be seriuosly whack to cause very low boost but nevertheless it's a possibility . Does the engine run smoothly at the lower boost or is it rough ? What AFRs are you seeing past 6k ?

*What type of clamps are you using ? Tbolt or screw type ? Some T bolt clamps are known to leak . Screw type are less sturdy but they don't leak .

*who installed the kit - can you be sure all the vac hoses are piped up correctly ? If not draw us a sketch and post some pics of what you have and we may see an error.

*Actuator . The stock actuator will do what you are describing to a certain extent anyway but you should still see 5psi at least .

* have a read of this thread - might give you some ideas once you get the initial issue sorted .
https://www.rx8club.com/series-i-major-horsepower-upgrades-93/getting-most-out-your-greddy-turbo-without-breaking-bank-172542/

* keep that intercooler - although the Greddy IC is not your issue . Later when you get sorted you may want to try it . 10" deep is ok as long as you mount it high enough to leave a 2-3" gap below it to allow air to the rad.

No - I am telling you that you are correct.

:) Wasn't sure if it was a cryptic way to say it was one of your customers and the tune was OK ;)

ok so tomorrow I will be tightening the actuator arm and doing away with the VDI. I just had a question, the local tuner on island doesn't seem to interested in helping me to fix the cars problems or anything of that sort, but he will dyno tune it for me for a pretty good price. What I mean that he isnt interested is that there is this boost problem so every time he tries to dyno he calls me to tell me to fix it, but the last time i asked him to just find the problem and fix it, I get a call from him telling me to pick up my car cause there is no room and to fix it and send it back. I am aware Mazda Maniac is a reputable tuner(this question is not personal) but would I be getting just as great of a tune from you MM, it seems the tuner with the dyno knows quite a bit of the rx8 but uninterested in my situation, and MM is a sure fire tune but does the dyno matter? I am just wondering cause this is taking quite a while to just get set on my way to a good tune. thank you

So the engine is running fine - just not making much boost is that it ? If it is not running fine don't go tweeking up the boost .....

well, it seems im getting a bit of misfire so im taking off my bhr coils, the engine does run pretty fine, i can totally feel it dropping on turbo side, so im gonna tweek the actuator, i really wanna drive my 8, ive had it for 6 months and driven it 1 week total.

Seems kinda backwards...

Does your tuner know how to adjust the Dwell to suit the BHR coils ?

obviously not, he said he had to advance timing a lot of my car(04) so he told me change it back to stock

Mazda Maniac are you open to tune my car? Im kinda tired of going back and forth with my car. I know your busy but just asking cause im getting the run around from hawaii people.

what island are you on, who is doing the tuning?

I ask because I spent a few years on Oahu, and I can tell ya there are only 2 or 3 people competant to tune a rotary there, and they arent people you'll find at shops - they are just guys at home like you or me, and even those(as of a couple years ago) wouldnt have had a clue about the Renesis and its nuances - aka modern tuning

well, this is at a shop. I didnt wanna drop names but sonics. They are hella busy so personal service is hard. They are super cool but I understand time is money. If there is anyone in Oahu that can tune a COBB AP for my car please let me know. thanks.

sonic motorsports? off nimitz, near sand island? purchase MM's tuning service....

MM tuning service is the only way to go for a custom turbo tune..(unless you put in countless hours of understanding how to tune a FI'd 8) be patient and it will be worth it..i have a MM tune myself

Idiot me, I tried to adjust the actuator arm but it was so damn hard to
put back, so nothing there. But I did order the MM calibration so I'm in good hands now. Cheeeeeeee huuuuuuuu

hard ? how so ?