TurboMazdaSpeed

Hi, Ok basic question....I have a single turbo setup with external wastegate, ATM its plumbed back into the downpipe for sound suppression, but i would like it to be vented back to the atmosphere.

So, Question: If i Re-Mod the wastegate pipe back to venting to the atmosphere again would it effect my tune at all?

Im running a microtech LT-10S, boost is at 8-10psi right now. My guess is it probably wouldn't really effect the tune since the wastegate pipe is beyond the intake / turbo and all, but im defiantly not a expert when it comes to tuning, just wrenching, lol.

Cars getting tuned in mid spring but in the meantime i drive it once or twice a month for fun

If anyone could let me know that would be great. If it would effect the tune ill just have to wait a day before i bring it in and do it, but would be nice if i could drive around with a open gate again with no worries

arghx

iTrader: (3)

It is possible that opening it up will affect the pumping efficiency of the engine which could affect AFR and the likelihood of knock.

TurboMazdaSpeed

hmm, weird.. that sucks. thanks

RX7(613)

iTrader: (9)

As stated above, wait till its your tuning time . Vent to atmosphere and retune.

Your afrs will vary, specially depending on your exhaust setup ( how straight flow or restrictive it is ).

why to you want atmosphere WG ?, things get loud quick.

zaridar

iTrader: (3)

YES this willl be very loud! I have mine this way... going back to the pipe when it all gets together...

TurboMazdaSpeed

Sounds accurate, dang. Well better safe than sorry!

Exhaust is full 80mm strait pipe to a huge steel wool packed greddy muffler --- for a bridgeport it is amazingly quiet once the turbo starts to spool

Personal preference, i love external wastegates, had them on my previous 3 cars (88 T2, 02 WRX STI, 1JZ FD3S)

Thats what the previous owners thoughts were too, lol. Then again he basically drove the car around bairly enough to break the engine in and then sold it to me

thewird

iTrader: (8)

A rotary vented exhaust sound is significantly louder then a piston counterpart. Just because you liked it with other cars, does not mean you will like it with the rx7 as well.

thewird

TurboMazdaSpeed

Had it on my 88 Turbo II , and my first T2 now that i think about it (my avatar pic from 06 lol) with a BIG external wastegate

They were both loud and i loved it! I had racing beat exhausts on both those cars also so so quiet when cruising loud when i want, perfect for my taste.

FD is odd weekend / track car only so loudness isnt a problem since i hardly drive it.

thewird

iTrader: (8)

Don't forget to check your local tracks noise regulations. They do exist for some.

thewird

zaridar

iTrader: (3)

well go for it then... im thinking it will affect your tune though since your o2 is probably in your downpipe...

black93RX7

Have had mine vented to atmosphere for several years, probably going to plumb it back in, just too noisy for a street car. People look at me like my car is gonna blow up.

TurboMazdaSpeed

hah... totally forgot about that, they do in fact have one. Maybe i should just leave it as is cars going on dyno this week! time to get rid of the break in tune.. excited to see what its going to make

zaridar

iTrader: (3)

nice..
good luck!