Aftermarket exhausts

[robedwards99]

Hi all.. I\'m new to the forum and I am currently seeking my first RX7!

I have Group 20 in Southampton on the case (anyone have any  experience of them??) looking in Japan for me, and they are sending me details of vehicles that suit my spec.

I am looking for a totally standard/unmodded Type R, but many I am seeing have aftermarket exhausts fitted.

I have read somewhere that this can be a major factor in shortening the lifespan of the engine, can anyone tell me more about this??? Are some exhausts ok?? Are some a big no-no??? or should I bide my time and wait for one to come along with the standard exhaust??

Any advice would be much apreciated

[ro284]

Hi mate, i know of some in the area, i live just down the road from you in Christchurch, i will pm you my number,
Bob

[scooby_si]

wouldn\'t worry too much certainly if it\'s only a back box normally it\'s time to look for an ECU for anything past a backbox & induction but otherwise not worth ruling out an otherwise nice car cause it has these....IMO
ECU is always nice thou
Si

[robedwards99]

Maybe I posted THIS in the wrong place as it\'s had no response as yet.

[scooby_si]

probably just not much folks can say really, AKA noone wants to say it\'s fine & then it goes pop hard to say anything concrete about a car without seeing it or havign someone knowledgable do so for you & of course while more info would help the real key question is what is it worth bidding to i\'d buy it for ¥100 but ¥1,000,000 would make it an expensive price in the UK....
Si (not much help either lol)

[scooby_si]

NB more info would help of course i\'m just not very good at the valueing thing.......

[ro284]

Rob you have pm

[robedwards99]

I should get some more info emailed tomorrow.. I will update in here then.

[robedwards99]

Back to the exhaust.... I just found this info on another site.

These cars, when fitted with just a few bolt on modifications, are capable of tremendous horsepower gains, but these modifications must not be lightly undertaken. Proper fuel enrichment to accommodate intake and exhaust flow improvements MUST be provided. If you are purchasing a modified car, make sure fuel enrichment has been taken into account.

Improper modification is another reason the 3rd gen. has a bad reputation for engine longevity. Initially, people were opening up the exhaust, raising the boost, and popping an engine at low mileage. The rotary engine will not tolerate detonation (pre-ignition) that is caused by an overly lean fuel mixture. If the fuel mixture is not adjusted (via an ECU "chip" or replacement) along with exhaust and intake modifications, then engine problems may occur.

A downpipe alone does not require any fuel enrichment. A downpipe, free flow muffler, and free flow intake combo will probably require more fuel to be safe. If the main cat has been removed, fuel enrichment is absolutely required.

[James S]

as Si says you will probally be ok with a back box and induction kit without any fuelling adjustment as long as the cat is still in place. if the cat has been removed make sure it has an ecu to deal with it!

:wave

[scooby_si]

yeah that sounds like a good little summary & i\'d advise anyone to look at ECU very early on the mod list.....
I do have an exhaust/catback i gota stick up for sale thou http://www.smileycentral.com/?partner=ZSzeb008_ZNxdm46052GB\' target=\'_blank\'>http://smileys.smileycentral.com/cat/7/7_18_4.gif\' border=0> lol
Si

[clive]

Originally posted by robedwards99
Maybe I posted THIS in the wrong place as it\'s had no response as yet.

Hi Rob and Welcome to Mazdarotaryclub.com.

The only way you will hurt your car is by doing to many mods as this will raise boost levels so the stock ECU cant adjust the fueling to compensate.

You will know this is happening because the car will fuel cut and actualy switch off the engine as you accelerate, and this IS bad for your engine.

Provideing you have a Jap import ( UK model ECU\'s arn\'t as tollerant) you can fit a Cat Back aftermarket exhaust / induction kit and they normaly will normaly be OK with a Cat removal as well, the above will happen if it\'s not.

If you are doing these mods your most important  upgrade will be a boost gauge so you can see if its boosting to high, look for 1 bar boost Max to be safe.

Any further mods will definatly require a programable ECU , with the Apexi PFC being the most popular by far on cars in the UK for this task, provideing your not going mad with mods you can litteraly plug these in and they will work out what is going on by reading the values of the electrical imput it\'s being fed and keep your engine safe.

Hope this helps.