been reading some posts about boost creep and how a ported wastegate is the best defense against it. I was thinking about the POV and from what I have read its sole job is preventing boost creep. Instead of porting your wastegate could you just install a POV?

-Ryan

 

I'm guessing you mean bov. blow off valve. I'd get a boost controller instead. I think bovs are mostly for show. they prevent turbo backspin yeah yeah yeah but our cars already have em.

 

No, there is such a thing as a pop-off valve, but from what I've heard, it will save your engine from overboost, but not the turbo itself (I think) Basically, if you have the stock 87-88 turbo, you need to port the wastegate or you will get boost creep. A stock airbox and 2.5 in downpipe will keep overall boost pressure down.

 

I emailed rx7.com and asked the same question, they replied that the POV is a last line of defense if the wastegate fails and should in no way be used to try and control boost....

Forget porting the wastegate...it's too time consuming...I've said this sooo many times on here, I wish people would try it, I've had great sucess. Got to www.jegs.com and buy a collector/header silencer and place it somewhere in your exhaust flow.....it will be able to keep the creep under control...it keeps mine under control even when it's 20 degrees outside.

 

Will this take away HP?

 

sweet thanks, I will take a look at that.
oh and for you guys that don't know what a POV is go to this link:
http://www.rx7.com/cgi-local/3catalog.cgi?cat=9&part=4

 

It's give and take...yeah I'm sure it does filter away a couple ponies up top, BUT, you also grab some low-end because of the slight increase in back pressure...

 

Hey Pressurized, how much do those silencers reduce boost creep? Under 12 psi? What mods do you have? Also, what does the exhaust sound like?

 

do you by any chance have a link that will take me right to the product you are talking about instead of searching the entire website for it?

 

http://www.jegs.com/cgi-bin/ncommerc...546&prmenbr=76

They have different configurations, I have the 3-disk for the winter then when summer comes I'll switch to a 1-disk...

 

hey pressurized, thanks for the link, what mods do you have and what psi are you boosting?

 

Well, that depends I guess on your mods.

Here are mine:

Intake
FMIC
DP
MP
CB
and I have the M2 ECU which is tuned to run 13psi.

So, after installing the MP I got boost creeps up to 18psi!! So I tried to figure out a way to get the boost down, and people on here mention 'restrictor' plates. So, I got one of these thingies. Now my boost on a warm day sometimes doesn't quite make it to the 13psi it's tuned for, and on really cold days it might go slightly over 13psi....

As for sound, it's a lot quieter at idle, and deeper...but at WOT it's still pretty 'killer'

 

that sounds perfect for me because I wanted to put on an intake, DP, MP, CB and Power FC and wanted to keep the boost between 10-12psi if I get an FD. Anyway, where in the exhaust do you insert the silencers? do you just un-bolt the MP and insert them there and just re-bolt it or is there something else you do?
I also thought the M2 ECU couldn't support a MP, do you have any problems running that ECU?

 

According to that rx7.com link, they say

"A great safeguard against wastegate failure or boost creep, the pop off valve releases any boost above your desired limit and helps protects your motor from a costly rebuild."

 

Haha...I think M2 isn't telling us a lot about their ECU's. There are people on the forum running larger injectors, midpipes...and even non-sequential on their ECU...I think they just make those calims to be absolutely safe I would suggest sticking with the Power FC though, the M2 unit is nice and has been serving me well, but I'm going single soon and there's no way it can support that...

As for the position of the silencer, I put mine right where the MP meets the exhaust....just because the exhaust has a much larger diameter so I can remove it easily if I want too...

 

Again, I'm not guaranteeing that this will work for everyone...but for $50, it's worth a try!!

 

pressurized, I know this is off the subject but with those mods have you had to replace the stock clutch yet. I read that it can only have around 300 RWHP and with that set-up you are putting out more than that.