i8acobra

1) what are the pro/con's of gutting the cats, not worried about smog.

2) overheating:
took out the stock fan for a 2950 cfm perma-cool fan, shroud is in there, car is overheating....could it be the thermostat? rad cap?

The Ace

1) Gutting cats: you gain a significant amount of HP, not as much as dropping a downpipe and/or midpipe though. Main con.....you dont care about the main con anyway, so....

2) Overheating: how have you connected the e-fan ? By a thermoswitch ? All the time ? How ? If the e-fan is indeed working as it should, and the car is still overheating, then it could be a number of reasons: thermostat, rad cap, air/coolant leak in hoses, radiator/cooling system needs flushing, or you could have water seals failure

Does the coolant overflow, or the car just overheats ?

scathcart

1) Pros: almost none. On a turbo, expect a boost increase and thus more power, but on an N/A, very little power (unless your cats were clogged).

Cons: You'll never pass emissions, its illegal, and you car will backfire and sound like ***.

2) Need more info on your car. Other mods, etc etc. You can check the thermostat by squeezing the hose with the engine running and warm. When you let go, you should feel a surge of fluid if it is working.
Rad cap is unlikely, but possible.

How did you wire the e-fan? How do you know its overheating? Do you have the belly pan and the plastic moldings in front of the rad in place?

i8acobra

heh, i should have included more info, jon's a ********....

i have an 86 n/a, only mods are the adapter and filter, and now the electric fan.

ok, on to business, cats: they are probably plugged...but i'm not sure, havent had a looksee, as for sounding like ***, are you sure? i would think it would have a better sound, then again, i'm new to the rotary...
also, with them gutted will the ports not open? if not, should i wire them open?

ok, electric fan: wired to a switch inside the car, i usually just turn on the car then turn on the fan. i know its overheating because the temp gauge is much higher than normal, all the plastic is in place.

thanks for the responces guys

RX-7Impreza

no sure about how it will sound, i dont have cats and mine soundsnice with stock mufflers, the ports will still open, if you ran headers alone you would have enough backpressure to open them so dont worry about it.

you can buy a thermoswitch at most autoparts stores

Justin

i8acobra

thank you justin, love your avatar btw, i'm not too worried about the thermoswitch at the moment, because if i cant get this thing to work, i'll go back to the stock fan, anyone know the cfm on that?

The Ace

Dont have gutted cats myself, but from almost every single post that I've read from guys that do have, they do not sound THAT bad, its just that the sound is more like a very noisy.....fart, for lack of a better word You essentially get the "fart-can" noise: prupruprupruprupru

As for the cooling problem, if you dont forget to turn on the fan , then it seems like something else is amiss. I think 2950CFM are enough (more than stock anyway), so no problem there. I would do the usual stuff first (flush, change thermostat and cap) just to make sure, and take it from there....

I had a cooling problem for more than 2 months, and it turned out that it was my turbo , which was dumping exhaust gases in the engine bay due to cracks. Go figure...

i8acobra

FART NOISES???!!!!! NOOOOO!!!!!!!! lol

SureShot

Make sure the thermostat fits. The spring loaded disc under the stat must close the bypass port, or guess what?

My 87 was showing overheating symptoms. What finally fixed it? Would you believe the water pump housing? The aluminum casting behind the pump was eroded by the turbulence of the high revving pump and too many years of running old coolant. The bypass valve seat under the thermostat had about a 4mm chamfer eroded away, and there was a 6mm hole eroded completely through the internal wall between the inlet and outlet side.
All this bypassing gives symptoms like a partially blocked radiator. I fabricated a repair with Bondo Marine Epoxy Putty Stick. It held for a year before I sold it.

scathcart

Its NOT your fan. I run the same fan on my 500 hp TII, and it keeps my car plenty cool.

Check for a clogged rad as well. Remove the plastic at the front of the car, and carefully (its gonna be hot) move your hand along the front of the rad surface. Try to feel for spots that are hotter than others. If this exists, you have a clogged rad, and will need to have it flushed. (an infared heat gun works great for this... but its expensive)

Check your oil bypass valve, located in the oil cooler. if it fails, the oil will not circulate through the cooler, and will make the car overheat. Again, using the same procedure as above, check to see the the oil cooler is hot as usual.

Change the thermostat to a Mazda OEM one. Its cheap insurance.

Gut your precats. Clogged precats will cause overheating, and leaving the stock main cat in place won't make your car sound like ***.
Yes, it will sound like a fart with gutted cats (all of them gutted). I know from experience, on my 90 TII and on my friend's 88 NA.
Better yet, buy a race pipe.

i8acobra

going to the dealership today for the mazda thermo

buy this buy that, i have about 600 dollars worth of bills coming up in about, 2 weeks. lol

but i shall gut the precat, (little more insurance? lol)

i8acobra

update: installed the thermo and new cap

car sits at about 3/4 now, as opposed to like 5/6, lol
grrrrrrrrrrrrrr....i'm pissed off......