Ahhrevenge

iTrader: (7)

I have an rx7 88 n/a with a straight pipe from downpipe to end.
I want to get rid of it and put an exhaust on it because it's too loud.
What are some things i can do to increase the power of my rx7 without adding turbo.

Please no rude comments or joke. Thanks.

ParadoxToday

well, with that straight pipe, your already losing power because your VDI (5/6th ports) arent opening.

InsomniacFC

iTrader: (4)

^^ +1.

There's a thread floating around here titled "beefy NA" that'll help out with the hp issue.

ParadoxToday

I suggest getting a Racingbeat full exhaust system, you will get a small gain in horsepower... and its not loud at all. well it gets loud'er' at WOT but its streetable and quite at low rpm.

.. hey that beats losing power and having a fart cannon right?

Also for your gaining horsepower issue, I dont suggest 'upgrading' to a cone filter,(unless you can fabricate a cold air box, or make piping to a cooler area) because the stock intake with a K&N drop in will gain more power because it is pulling in colder air, rather then the hot air from your enginebay.

If your really serious about it, you can beef up your fuel system, (fuel pump upgrade, injectors.. etc). and ultimatly go standalone and tune your car. If its a goal your serious about you can get a rather large street port and increase your numbers with a good tune.

Foxtrawt

so if you have a full exhaust system with no cats, or a stack exhaust with the cat taken out, your 5/6th ports wont open?

ParadoxToday

Ahh, see depends.

S4: No, unless youve rigged some other backpressure system to actuate the ports..

S5: Yea, because the Cat isnt needed... the airpump is.

Im assuming he has no aux ports opening because he seems rather new and hes asking how to increase power.. so you usualy think a person like that could not rig up their own backpressure system to actuate the ports.

Foxtrawt

hmmm, alright.. well, I'm new here and newer with rotaries, I've learned a **** load on these engines, but thats something I didnt know... the cat was out of my car when I got it, but I didnt know it wasnt letting the 5/6 ports open. How hard is it to make a backpressure system to sctuate the ports?
thanks

ParadoxToday

Well, honestly I dont know.. I have never done it.. Try researching on this forum.. you will find your answer,
https://www.rx7club.com/search.php?searchid=8198822
look through those topics you might find what you need... best suggestion is what i told the OP, Get a full racingbeat exhaust system, it has no cats but the presilencer has the air return adapter on it so you can have working VDI, you will notice a good boost in topend power around the 5k rpm mark with a functioning VDI.. Good luck

ericgrau

iTrader: (1)

1. Add a presilencer and quieter performance mufflers. Ditch the noisy header; a cat replacement pipe is almost as good according to Racing Beat, dynos and my own engineering sense.
2. Get your auxillary ports (aka 5th and 6th ports) working. Search forums for ways to activate it, such as using air pump pressure. Hope you still have your air pump.
3. Beyond these exhaust items adding more power is hard. You can tune it or get a street port. Do a forum search for more info. Other things that are easier but don't add much speed: Cold air cone intake, better oil, higher final drive ratio, weight reduction. Yeah a couple of those make you faster without adding horsepower, same difference. Again search for more info. Beyond tuning and porting your best option is probably to be satisfied with it or get a turbo.