Hey guys, help a chick out! I know my car (87 na manual) is lacking power, i'm thinking maybe my cats are clogged (or it could be bad fuel injectors) It idles wierd and just will not accelerate, grr... It also gets quite hot underneath and the heat is felt under the seats. I'm thinking about gutting my cats, but i want to make sure, so what are other symptoms of clogged cats. And i have never done anything like this before--i don't know how!-- so any steps on how do do this would help, or suggestions on how else to do this besides gutting my cats. Thanks!

-Jessica

 

You can check for disintegrating cats by lightly taping the cats with a rubber hammer. You will most likely hear something that sounds like gravel inside if they are coming apart. You can also shake them if you are strong enough and see if they rattle (they shouldn't) . As for gutting them....I just did mine...not that complicated but not easy to get all that stuff out either! You just take a hammer and a LONG screwdriver and keep poking and pounding that stuff until it comes apart. DON'T BREATHE THE DUST!

Todd

PS. If you can feel all that extra heat coming off them then clogged cats are a good bet. You might check with the N/A guys to see about the 6 ports.....you might have to do something to get them to work if you gut the cats (i'm not sure...mine's a turbo ).

 

Ok, to start with, if you are going to gut your cat, it's best to make sure it is dead first. If it isn't dead, it will make loud noises, scratch, and bite. The people from PETA will be all over you in seconds...

Oh, wait... you mean your catalytic converter on your car?

Unbolt the exhaust and drop it... take it apart at the joints... use a BIG scredriver and a hammer to break up the parts. DON'T breathe the dust!

With a stock cat-back (that's the part of the exhaust running from the catalytic converter to the rear of the car, not the spinal section of a cat... ) you will probably still have enough backpressure to open your six ports. You can test them by putting a dab of grease on the rod where it enters the actuator... take it for a "spirited" drive, and look to see if it got shoved up the rod a bit... if so, they are moving. Rotate them by hand, and see if they were opening all the way by seeing where the grease got moved to.

 

hmm, gut ur cats..u COULD do that, if ur from tennessee, and drive a 1979 camaro.

why dont you just havesomeone unbolt ur exhaust, and take out the whole assembly from ur MAnifold, all the way to ur Y pipe. then take it down to the local muffler shop, and have them bend up a pipe w/ the SAME flanges, same bends, and SAME diameter. and then just bolt up the Straight replacment pipe. NO cats, no weird uneccesary expanding and contracting of the pipe (from hollow cats) and NO problem. and if u EVER get E-check in ur part of Ohio (where is that, by the way?) you can bolt ur cats back up and Try to pass it.

thats what im gona do, Screw payin 180 bucks for a 'Race' pipe...ill have one made for 50 bucks.

chris

 

Well, in California if a cop checks to see if you have a cat, and sees a test pipe where a converter should be, 2000 dollar fine. However if you have a hollow cat, you will at least pass a visual and at the very least can BS your way why the car smells so bad.
If your cat is still good, and you still want to straight pipe you can either buy a cheap new cat and hollow it or have a muffler shop make you a test pipe. Do not hollow a good factory cat!!! Most aftermarket ones are garbage.

 

good thing she lives in little old ohio where we dont have smog issues. besides if a cop pulls u over and askes where ur damn Cat is... it probably means he doesnt KNOW about RX7s....so u can BS.

cuz anyone who knows our cars, knows they have at LEAST 2 cats...(Freakin mazda)

so just tell him, you had it imported from japan, and its not Made to american specifications, and its EXEMPT from emissions laws. hehe, doesnt have to be TRUE, just as long as you sound like u know what ur talkin about.

theoretically, all cars after 1975 should have a Cat... i used to have a 78 blazer that had a 350, true duals, NO CATS...and it came from the factory that way. so thers lots of loop holes. and, whos the cop to say that ur car wasnt supposed to have cats... unless hes a Freakin walkin encyclopedia of RX7 trivia.

if he gives you **** about having a 'TEST' pipe on your car, just TELL him thats exactly what you are doing; Testing your car, and ur doing a test drive, and u were Just about to take it back to the mechanic.

wehres theres Doubt, theres a way out!

chris

 

hahaha

That was so incredibly cheesy and stupid, yet I found it so funny. lol

My main cat is clogged. Still trying to decide what I want to do about it. I may pull it off and have a pipe made to replace it, leaving the precats in hopes that it'll help with the noise until I can afford a more permanent solution.

 

Every one said that there were no girls into their RX-7s as much as we were. A few days later one popps up wanting to gut her catz. how cool is that?

 

Just to let ya guys know,,, I have a straight pipe, 0 cats.. and the stock exhaust on my 86 Base N/A .... And my acuators open at about 3800 ...... EVERY time =)

 

Cats we don't need no stinking Cats !!!

I had to wire my actuators open

But I am having a straight pipe made from the maniflod back... Should be a little step up in power and be able to blow flames. If not I guess slighty bigger injectors

Jessica do you want to blow flames out the back with those cats gutted? might happen

 

hey thanks for all the advice. I like the sound of getting simple, cheap, straight pipes made like Chris said. I am kind of worried about getting an e-check later, but i just had it done and won't need it for another two years (our e-check station is in elyria) I'll have to tell my friend about the pipe too, he wants one. I still might gut them though, my car is so quite, sometimes if i walk away i can't hear her, and i would love that loud sound when i get up to those high rpms on the highway. just that sound and sense of speed and power is exhilarating. and Flames shooting out would be cool and i get lots of looks. I also love the looks i get from guys when they see a chick getting out of her awesome sports car.

As for the cops. I have no problem with them, especially in my hometown, they all know me. and it is easy to talk my way out. I've been stopped by cops 3 times in my year or so of driving and haven't gotten one ticket yet.

ragtop, i liked your joke too. I had to laugh. i may hate cats but i would never really gut one, maybe shoot one with a hose when i'm washing my girl.

And yes boys, i do love my car and i'm trying to learn as much about her as i can. I've only had her for 3 months. Sorry i'm not on here much, but i don't have online at my home. i'm sure i'll be back to ask more questions.

Thanks guys!

-Jessica

 

bwaahahhha Brad, I don't know why, but that made me chuckle.

I put on some headers and a pre-silencer, but hey if you can get the straight pipes made for $100 or less, by all means go for it. Much better than pounding the cats, plus you never know if you will need them (if they are still in good shape). Just make sure the ports are opening after whatever you decide....

 

Ahh whoever that was looking at gutting your cat. Well I have the same setup on my 90 GXL. I gutted the 2 cats. If you do that, just make sure you have no exhaust leak as those nasty fumes will just leak in your car and make your new clothes smell like the car everyday. A trick i learned is that always drive with the a/c on and always close the door when the car is on. Also never walked behind the car with no cat as it will stink you up very quickly.

Last advice about gutting your cat is that your car will sound really really funny. It sounds like something is echoing. Instead of the nice exhaust note like zoom zooom. You get these rattling sound. Sounds like crap if you ask me, but works good

 

okay, i have an offer to get a cheap new cat, but my question is... which one would give me more power, gutting my cat, getting a pipe made, or buying a new one?
right now i have VERY little power so anything is an improvement, but what would give me the most???

Thanks
-Jessica

 

Hi all, but this is the first reply I have made on this forum.

Bolting in a test pipe will net the highest horsepower gain. Of course a good header would also help quite a bit (such as racing beat's).

When you hollow the catalytic converters, you leave empty cavitys where the catalyst used to be. These cavitys are big empty spaces that mess with exhaust gas velocity. You want your exhaust to be moving as fast as possible to make higher horspewer. But, like everyone said, hollow cats are a lot more legal than a test pipe. And depending on whether you know someone in an exhaust shop, they can bend you up a test pipe and weld on a couple of flanges real cheap. But, its also kind of illegal for them to do that unless the car is going to be for "offroad use only." Dont we all just love that saying?

Anyway, hope I may have helped a bit,

Jason

 

Wanna talk clogged...I've got an 88 SE w/ all original exhaust(yes, all original..including mufflers)...
...The most power would be the straight pipe...the gutted cat would be cheapest, and the new cat would be a lil bit of both. A new cat would give you a nice gain(depending on which aftermarket cat you get) but it will cost a little bit of cash too...
Its all in how ya see it. I think I'm just gonna do a Superflo system hooked into either APEXi N1 Duals, S&R Motorsports 3" catback, or RB cat back.....Good luck.

 

hey, i dont think she is talking about a Bonez hi flow cat...i could be mistaken, im sure the guy down at the muffler shop told her about just REPLACING the old cat w/ one he 'sells for $86.99 all day long. its a Catco universal fit converter'.

Champagne, DONT get the universal converter, if u ever plan on buying a new Cat for ur car, it MUST be made specifically for the RX7...cuz our rotaries have no valves and what not, the exhaust still comes out of the engine PIPING hott...its hot enuf to MELT the monolith element inside Plain Jane universal converters. and, whiel were on the topic of Exhaust parts not Lasting... NEEVER get a glass pack for ur car, sure its striaght thru, and might sound like a good idea. but w/ the heat coming from the exhaust, that muffler will burn out in a matter of hours, maybe days if ur lucky.

My muffler guy wanted me to buy his Universal cat instead of installing a straight pipe. hes like 'nah, thisll work on ur car, its what u got now' i told him 'no, these are special converters' HE SAYS "naw, its the same as this one, I SELL THESE FOR $87 ALL DAY LONG" i told him "no you dont understand, normal cars have exhaust temperatures of 900-1200* F...MY car runs at 1700* F....CONSITANTLY...taht cat will burn out, melt and get clogged" i forget what he said, cuz i didnt wanna hear his speil...all i said after that was 'look, just put the cut out on.'

i got tired of my cut out, so now what im going to do is:

Unbolt entire exhaust from Manifold to where Y pipe meets mufflers.

GUT pre-cat #1,

have Custom straight pipe 2.5" dia made from Precat #1, all the way to where Driver's side of Y pipe meets muffler.

Have Arospeed Bomb muffler mated w/ intermediate pipe in order to bolt up to end of DRiver's Side of Y pipe.


this way, i will have a tuneable muffler, it will mount and hang just as easily as the original one w/ the same fit and finish. and i will still be technically legal. i will have a catalytic converter (gutted) just for looks. so if a cop gets down on his hands and knees, gets dirty in his uniform, and SOME how manages to see up under my car, despite the fact that it practially scrapes on speed bumps: He wont be disappointed!!!

and he will say 'WELLllll then...everything seems to be in order, heres your liscense and proof of insureance back...you have a good day, and be careful out tehre'

(Can you tell, ive been pulled over enuf times to know their lines? haha!)


i suggest you try my methods...youll find that you will have ur Custom "off-road use only" exhaust w/ a Seemingly legal catalytic converter. and when Echeck rolls around, you will still have your complete original exhaust to bolt back up, including the TWO other working cats: Precat 2, and the Main cat. DAMN IM GOOD! as for the 6 ports working, just wire them open, save urself the trubble. if take off from a stop like mom does, you wont have any problems. the fact that you lose low end tork when the 6ports arent workin, is offset by the FACT that we have a stock heavy flywheel.

anywho, sorry this is SO long, if u got any Questions, let me know here, or PM.

chris


PS: just for ***** and giggles, i drove my car around w/ NO EXHAUST, open off the manifold...GODDAMN! ive never felt it so fast in my life. my 6PI is wired open, so once it wound up to about 3000 rpm..that thing would set u back in the seat!...i could take off from a stop sign, turn right, and floor it as soon as the clutch was released; it would speed upslowly up till 3000 rpm, which was about where i pass the Apex of the corner, about 14 mph, then she BUSTED OUT man! tires blazing, smoke whisping off the tires, *** end hangin out, winding up to 7000 in NO time...grab second, car straitens back out. BTW...its loud as a **** w/ open manifold. grabbing 3rd, that baby SQUATS Hardcore man! it is alot faster getting up to highway speed, and 40-80 mph... enjoy!

 

Thanks again guys!
the reason i would get on cheaper is because my dad is actually willing to pay for over half, so if i get a new one i'm going to check our rx7.com or if you guys know of another place i can order a good cat for rx7's. And this week i'm going to check out some muffler shops and see what they have to say about making a pipe. And i'm still not that worried about the cops around here at least. if ever need be i'll keep my cats. Thanks again!

-Jessica

 

I cant much vouch on the going faster part with open from the manifold ( 6ths probably werent even opening) but I will vouch for the my babe be louder than hell. At idle it was about as loud as my friends 79 camaro chevy 350 sb /w straights at idle. Revving past 3000 was just scary, the stereo couldn't even drown it out with teh windows up. I feel bad for whomever was next to me.


BTW always tighten your exahuast well w/o too much torque. I over torqued and must have broke the bolt. Driving down the road, I run over my own exhaust. Not the brightest thing... but after I let it cool, you can open the hatch and the exhaust fits right up to the frotn dash. Only way I knew to get it home. haha, have fun all. I'm looking at a tranny install tomorrow!

 

What about a straight pipe for a s4 TII? Too loud? lol
I have racing beat cat-back exhaust on now. what do you think about going to a 3 inch exhaust to the y pipe? or is that useless?

 

I havn't read all of this thread so if I say somthing someone else says don't mind it. If you gut the cats the car will sound different meaning it will resonate, and I think it sounds kinda like a fart pipe to me. And another thing from now on when I post threads I'm going to start putting hot chick with big nockers in need of help, maybe I'll get better turn outs.

 

with a 3 in. from the turbo to the y-pipe it'll sure be a bit lounder, but not as loud as it would on an n/a, although you might get some boost creep and hit fuel cut and blow your engine without fuel mod

 

Do you guys realize how old this thread is? lmao...

 

nice call rotor13b...lmao 2 years old

 

wow...some clown must hav been searching and found it...

----------------->tykelley27

hehe