Exhaust Valve Motor Thingy In Boot Of My Na 33 Gts

[Samon]

Hi all,

I was poking around in the boot of my 33 the other day changing one of my reversing globes, and noticed (not for the first time, but never bothered to investigate before ) this motor mounted beside where the jack is stored. It looked all factory, and you can see it is supposted to pull a cable.

I did a bit of searching and saw a suggesstion somewhere that it could be some sort of exhaust valve actuator... so i got my dad to give my car some revs while i watched it... nothing... anyway i got him to watch it while i gave it some SERIOUS revs... and he exclaimed that it moved... sure enough i got him to rev it HARD... i.e. 6500ish RPM, and yeah it does move somewhere around the 4000RPM mark i think.

There is no cable attached to the motor, and obviously no exhaust valve or whatever hooked up to it, but i'm wondering whether it would be worth hooking up. My exhaust was FREAKING LOUD... then i got EPA'd for noise pollution, now it's just LOUD (i.e. bang on 90dB but it looks crappy with a single 2.5" piece of black pipe where there once were two massive 3.5" stainless cannons ). I would like put the rear half of the 3" exhaust system back on (they cut the old one at the same place where they put the flange for the two-piece 2.5" system), and wondered if i could put some sort of exhaust valve (i.e. APEXi ECV or similar) in between and connect the cable up to this motor... that way under say 4000 RPM it would be nice and quiet.... possibly even having a bit more backpressure for the down-low torque that it misses with a larger exhaust (we're talking NA here...), but then if I'm really giving it some stick it would be open enough to allow more top-end power where i really dont care about noise... lol if i get EPA'd again i'd just disconnect the cable to the exhaust valve motor . The best of both worlds???

it would be something like (excuse the crappy ASCII art):

                                     [exhaust motor thing]
                                              !
_________                                     !
|         |                                    !          /=====[3.5" Cannon]=(
| RB25DE  |====[CAT]=====[RESONATOR]======={[VALVE]}=====(  2.5"
|_________|          2.5"             2.5"            3"  \=====[3.5" Cannon]=(
                                                           2.5"

Is this motor standard on all 33's? was there a factory option for a variable exhaust? I have done a lot of searching and found a fair bit on them for the 34's, but not much mention for 33's. Can anyone see a problem with my idea?

[jonzie26]

are you sure that its not the motor for your aerial?

[Samon]

are you sure that its not the motor for your aerial?

Absolutely. Why would the aerial be going up and down depending on the engine RPM?

After a fair bit of searching, it would appear that some models came out with a kind of exhaust 'flap' that opened and closed to increase backpressure down low and provide maximum flow high up in the rev range. I've actually got an APEXi ECV valve fitted in the exhaust, but no cable hooking it up to the motor yet (lol been there for months now though!), so it just stays wide open (VERY LOUD).

Gonna be turbo-ing 'er up very shortly (got everything to do it, just gotta find some time!), so I'm fairly sure I'll want maximum flow all the time anyway.

[jonzie26]

Just a suggestion. I also have a flap in my raer muffler. but i put it there. I have a Varex muffler on my gts-t. it is a very nice piece of work. with the valve closed it is super quiet, then with it open it is loud, but not to loud to get attention from the police.

[(B1) MR_fanny]

my mate had an n/a 33 and it had that factory exhaust flap you talk about

[(B1) MR_fanny]

my mate had an n/a 33 and it had that factory exhaust flap you talk about. something about controling exhasut back pressure

[ignuz]

yea my old R33 with the stock exhaust, I noticed that when looking down the rear twin tips, one was open and one was shut.

The other one opens when you really give it the gas.

Doesn't serve any purpose now though if you replace the exhaust as there's no flap there to control anymore.

[NISZILA]

All it does is close one pipe off at low revs and open it at higher revs on the stock muffler. It is a vacuum valve. If you have replaced the exhaust, then this will do nothing for you as your valve is not longer there

[Jack88]

mine too has the actuator set up but it already had an after market exhaust on it so no flap in the muffler.i had never seen antoher 33 with this on there before.

[Brianfidge]

I’m currently paying off a 33 and had a look the other day and it’s got the motor and standard real muffler that’s got a valve inside was trying to figure out if it was off a switch or not but if it opens at a certain rpm I would say it would open up to release pressure or something

[niZmO_Man]

Huh? Since when did Nissan bother to have variable mufflers in the 90's?

[Rusty Nuts]

42 minutes ago, niZmO_Man said:

Huh? Since when did Nissan bother to have variable mufflers in the 90's?

They just DID mate, suggest you direct that inquiry to Nissan, although who gives a f#ck now.