Like title says. I ported my WG and still have boost creep. It is ported to apprx 30mm. I used an exhaust valve for the flapper door. Any other ideas as to why it could still be creeping? Thanks

 

The actuator may be sticking or leaking?

 

how would i test that or check it? Thanks

 

heres how big i ported it

 

That sucker shouldn't be creeping. How big is your exhaust/intake? That port looks excellent too. You can test the actuator by using a hand pump and attaching it to the actuator and check to see if it is opening properly.

 

I have the apexi gt spec exhaust and DP. The exhaust is 3" and DP i THINK is 2 3/4 but not 100% positive on the DP i made a TID that is 3"

 

nvm i see pics

i dont see a picture and on aaroncakes how to it says to go to 38 mm

http://www.aaroncake.net/rx-7/s4wastegate.htm
but then again its s4

 

Get bigger secondary injectors and learn to love the creep. Seriously though the intake/exhaust combo you have is most likely what is causing the creep. I have seen a few who modified the stock manifold with an aftermarket WG. Maybe something like that. Like this thread. https://www.rx7club.com/showthread.p...rnal+wastegate BlueTII did something similar with his BNR as well.

 

Damn, if you're still creeping (beautiful port btw, CNC mill or how did you do it?) I might as well just go straight to an S5 turbo. I ported mine a while ago, but since my wg is now sealing properly and my twin scroll is working I boost like crazy. I doubt I can beat that port.

 

what if i have a s5 turbo and im still creeping to like 15-16 psi btw i have 3in dp highflow cat to rb catback

 

did you port it? While the stock s5 WG is better than the stock s4, I doubt it's better than that beautiful port job shown above. If you're creeping to 15psi with stock fuel, you better fix it real quick or your engine will pop soon.

As for OP, only real good suggestions is to follow Aaroncake's writeup as linked to above. Or buy an s5 housing/manifold and port the crap outta that one.

 

I'm gona pull it back off and port it more I guess

 

Nope sorry still running stock turbo.

Dont waste your time. Honestly the problem isnt in your WG. Well maybe some, but even after we installed the Tial 38 on my car I got over boost. So what we did was restricted the exhaust some by welding small plates on the downpipe. Apparently there is alot of exhaust flow and after welding some plates on the exuast the back pressure stopped my over boosting problem.


Not a good idea. During cruise my car intake temperature reads 5 degrees Celsius. This is with outside temperature around the 40 degrees Fahrenheit.
When I floor it (still at the same 40 degree temp) and I reach 12 psi, My intake temps reach 68-72 degrees celsius...I dont even wanna know what happends at 15 psi like this guy says.

The fact that you can add fuel to the car doesnt mean you can boost what you want. The turbo is just way too small and doesnt really like to hold boost after 6k rpms. Exhaust temps are high as hell and it does affect your intake temps. I mean the turbo is only next to the intake

 

Nope.. i've got a 38mm, and i found that at stock 7 psi it doesn't open it enough, with a FCD and the wastegate seeing 11psi, it opens enough to keep it at 11psi.
it's my personal magic number. but when i went to 38mm i wanted to keep it at 7 psi. GOAL FAILED.

Another option i have used it to get some old carb springs from autozone HELP! section, and hook them on the wastegate door actuator and stretch them to the body, i could hold 7 psi in 2nd and 3rd like this, although it did creep to fuel cut in 4th gear with about 1 degree C outside. (33F) i'll take pix in a day.

 

I only said BlueTII was running a BNR I didn't say you weren't running a stocker. I was also joking about learning to deal with it. Do you have a front mount? Those intake temps are CRAZY! I see about 70+-10 degrees cruising with 60-70 degree day. I don't really ever see above 100 when I am driving very hard though. A lot of times my intake temps drop in boost.

 

I apologize if my next question has been answered. I am posting from my phone.

If I am unable to keep boost from creeping what should my next step be? Aftermarket WG? Upgrade injectors (or have mine sent out to be cleaned) ? Thanks again for all the help. This boost creep is a pain in the ***

 

Maybe something like 2-N-D Pink said about restricting the exhaust might work.

 

test the wastegate actuator, they do still fail.. make sure the diaphragm is holding pressure and not bleeding it off through a pinhole leak/crack.

 

I read on here that there is a way to test the actuator with a air pump. Is that true. I looked last night for a how to but was unsuccessful. Any help with that would be appreciated

 

Absolutely, find an attachment or adapter that can be easily sealed to a vacuum line. I used one like this:


The tip screws on so it could be used with a threaded hand/foot pump. There are two common thread types though so make sure you'd get the right one.

 

Nice job porting the gate. I have a failsafe solution to your problem. Take the back plate off the turbo, cut a hole out where the flapper is and make sure the flapper when it opens actually opens further then stock and into the new hole you just made. Now weld a tube over the hole and plumb that back into your down pipe 18" or so further downstream. Now make a little divider and weld it to the backing plate effectively separating the turbine discharge hole from where the waste gate used to flow into the same hole. This solves a couple problems. 1: Being it allows your flapper to open farther. 2: It gives your waste gated exhaust a straighter path instead of the hard 90* out the flapper hole, then 90* out the down pipe. 3: It also keeps high heat and velocity of the exhaust existing the turbine from inhibiting waste gate flow. It also enhances turbine discharge if you port the turbine discharge to be shaped like a smooth cone from the turbine wheel to matching diameter of the downpipe. I've suggested this to several friends over the last 10 or so years and all of them it worked and they had rock steady boost of 7 psi on large hybrids running 3" or larger exhaust running after market EMS so no TID. My buddy DCEE on this forum did it about 7 or 8 years ago, you might be able to find his write up. He has a 13b turbo'd 1st gen with a T04E hybrid.

~Mike.............

 

[QUOTE=2-N-D-pink;9844917]Nope sorry still running stock turbo.



Dont waste your time. Honestly the problem isnt in your WG. Well maybe some, but even after we installed the Tial 38 on my car I got over boost. So what we did was restricted the exhaust some by welding small plates on the downpipe. Apparently there is alot of exhaust flow and after welding some plates on the exuast the back pressure stopped my over boosting problem.




any pics of what you welded? thanks

 

SERIOUSLY?? stupidist damned advice I've ever heard.. add a bunch of performance enhancing devices, then weld RESTRICTORS to cancel them out so you can control boost. WTF?? Yeah, go ahead and downgrade every thing you've done, screw doing it the right way and maintain performance.. REALLY? You think a free flowing 3" exhaust with RESTRICTORS performes better then stock 2.25"?

~Mike...........

 

^^^ that was my thought, but I'm not going to weld a dump pipe into my costly stainless system either. That's why once I can I'm just going to get an S5 turbo and manifold. That's my advice for flo here, too.

 

Dump pipe, improves boost control and adds performance in every aspect.. hmm ok, your car, your choice.....
BTW, if you decide to make that S5 turbo a hybrid, your still going to have problems with boost control, even after its ported, unless you restrict your exhaust of corse, which would lead to the question, WHY BOTHER UPGRADING ANYTHING OR MOVE TO AN S5 TURBO? LET ALONE A HYBRID??