I need help with costom exuast setup
09-11-04, 07:18 PM
#1
Drifting Is Fun
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Location: Houston,Tx
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I need help with costom exuast setup
I need a new exuast for my car it is an 85 rx7 12a. I need it to still pass inspection but I would also like a power increase as well. I was thinking a RB road race header with 2 cats one for each rotor then collecting into one borla muffler. The cats I was thinking about were dyna max there specs look pretty good but there price is around $150 a peice. If it is loud it is fine with me just as long as it passes inspection. Oh if I use 2 cats could I get rid of the airpump? Any advice would be greatly appreciated thanks. 
09-11-04, 07:43 PM
#2
FB+FC=F-ME
Have to keep the airpump if you run cats.It only takes 1 or 2hp to run and the cat(s) will melt down/clog without the oxygen provided by the airpump and ACV to distribute it.
Id stick with a single catylist.Just get one thats large or made for a rotaries heat.2 parallel cats will just take up more room and make the exhaust more complex.
Heres what Sport Compact did on a stock 83 w/12A a few years ago.....
Stock 12A,all smog gear intact.
RB standard header.
Random Tech catylist(their largest core is exactly the same length as the RB presilencer,so it bolts up perfectly between the RB header and the stock midpipe)If you use a Bonez or other,smaller cat,youll have to weld a little to fit the gap.
RB Powerpulse muffler.Use any muffler you like,but Itll likely be loud and not hold up for as long as the more pricey RB.They really are bulletproof and quiet.
They went from 1400PPM of hydrocarbons to only 4PPM.Well enough to pass CA emissions(120PPM),let alone any other state.
Although technically not legal in CA since the header wouldnt pass visual inspection,they proved that HP could be made without removing any smog devices and they cleaned the car up A LOT,while increasing power.They made about 10-11hp more than with the stock manifold,pellet catylist and muffler.
Id stick with a single catylist.Just get one thats large or made for a rotaries heat.2 parallel cats will just take up more room and make the exhaust more complex.
Heres what Sport Compact did on a stock 83 w/12A a few years ago.....
Stock 12A,all smog gear intact.
RB standard header.
Random Tech catylist(their largest core is exactly the same length as the RB presilencer,so it bolts up perfectly between the RB header and the stock midpipe)If you use a Bonez or other,smaller cat,youll have to weld a little to fit the gap.
RB Powerpulse muffler.Use any muffler you like,but Itll likely be loud and not hold up for as long as the more pricey RB.They really are bulletproof and quiet.
They went from 1400PPM of hydrocarbons to only 4PPM.Well enough to pass CA emissions(120PPM),let alone any other state.
Although technically not legal in CA since the header wouldnt pass visual inspection,they proved that HP could be made without removing any smog devices and they cleaned the car up A LOT,while increasing power.They made about 10-11hp more than with the stock manifold,pellet catylist and muffler.
09-12-04, 08:51 AM
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That was what I was gonna do but the cops around here are checking for that kinda stuff. And I don't like racing beats high prices and I am not going with pacesetter.
09-12-04, 08:43 PM
#5
FB+FC=F-ME
Theres nothing wrong with running a clean rotary!:-)
You can have your cake and eat it too.If you dont have to pass visual smog inspections and the only thing that matters is the sniffer test at the tailpipe,then your got it made.Here in CA,the reffs will flunk your smog test if you add ANYTHING to the engine that isnt CARB certified,even if it doesnt affect the tailpipe emissions!
Sport Compact proved that the RB headers dont affect smog output,but they are still illegal to have in CA because RB didnt get a CARB certification for them (headers delete the precats,which do nothing anyways once the engine is fully warm)
If visual inspection isnt an issue,it can be cheaper than getting a full RB exhaust.You only need the header,and the cat will help cut noise so you dont HAVE to buy a Primaflow to get it decently quiet.Just get a Magnaflow or somn'.
You can have your cake and eat it too.If you dont have to pass visual smog inspections and the only thing that matters is the sniffer test at the tailpipe,then your got it made.Here in CA,the reffs will flunk your smog test if you add ANYTHING to the engine that isnt CARB certified,even if it doesnt affect the tailpipe emissions!
Sport Compact proved that the RB headers dont affect smog output,but they are still illegal to have in CA because RB didnt get a CARB certification for them (headers delete the precats,which do nothing anyways once the engine is fully warm)
If visual inspection isnt an issue,it can be cheaper than getting a full RB exhaust.You only need the header,and the cat will help cut noise so you dont HAVE to buy a Primaflow to get it decently quiet.Just get a Magnaflow or somn'.
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