Hey guys,
I was just wondering what are the options for our primary cats? I know E-Shift used to make a complete set; but i guess they discontinued those. And i read about the pre-cat deletes...which i am iffy about, mainly because of the check engine light and air fuel ratios. I have a third highflow cat from RT already... what do you guys suggest?

 

moved to the performance section.


I think that another company makes them, I think it was ATLP....

 

I think the pre-cat deletes should be fine. They don't set off the CEL because they come with O2 simulators. It also shouldn't mess with the A\F ratios because it's on the post combustion end of things.

 

I concur.

 

send me a pm if you want highflowing cats made

 

well, i thought the vehicle runs on information provided by the o2 sensors/ atleast the primaries. So if the car is running too rich at a specific moment; it would richen up the combustion and vise versa if it was too lean.

 

precats: www.rv6-p.com

I'm currently waiting to install mine

 

WOW 15HP, but BAD for Planet EARTH brothers and sisters.

 

^^ It evens out because of all the people that bought the toyota prius

 

Will the pre-cat deletes cause the vehicle to fail inspection? Are they legal?

 

it will result in failure of emissions if they put in the tailpipe sniffer. you have a better chance if you leave the 3rd cat in. these are made for "off road use"

 

I believe my inspection place uses the harness for newer cars and not the sniffer, which Is for older cars if i'm not mistaken. My next inspection isn't due for another 3+ years. If the deletes would be a rather simple/quick swap I may consider picking them up. Maybe even in the RV6 combo deal as I'm getting a j-pipe anyway.

 

what does "off road use" mean? i live off of dirt roads, so am i good?

 

"off road use" means that it is designed for track use only. technically not allowed on the street

 

great products..no CEL

 

if i already have a j-pipe and race pipe from ATLP:

1. what mod would give me the biggest bang for the buck...the pre-cats or a catback exhaust?

2. would adding both be worth it, if not why?


i realize that one is $250 while the other is around $1k, but i have heard that adding the cat back to an already modded front end wont equal as much gains, especially adding the cat back and pre-cats together...

sorry for going off topic, i just didnt think it was that important to make another similiar thread.

 

Precats = 15-20whp(with catback exhaust). Catback 7-11whp.
Precats without catback would be around 13-18whp

Pre cats has the best money to hp ratio. But a catback would be nice. Since you stated that you are going to buy 1 or the other, just buy they both. The precats are only $250(IIRC) more. Or just buy the CB then wait a week and buy the precats

 

will pre cats void the engine warranty?

 

Whats the longs someone has been on the pre-cat delete w/no engine lights or engine problems.

 

no one has had any CEL's or problems due to the pre-cat deletes. the Oxygen sensors are tricked into reading the right levels so no CEL is on for the sensor. As far as engine problems, none have been reported yet...

 

Hmm... about 9-10k on mine... no CELs ever...

also gained a whopping 20whp on the dyno

 

Thats the thing i don't understand with the oxygen sensors being "tricked".
OBII computer solely operates off the O2 sensors. When the car is cold; "open loop" so the car runs on "limp mode" which is the preset factory specified air/fuel ratio map. Once coolant temperature sensor sends signal to ECM that vehicle is up to operating temp and O2s are warmed up ECM goes into "closed loop". And in closed loop A/F ratio varies and chances every msecs.

 

I don't think they o2 sensors are tricked. Because all they do is sniff the fumes to detect how much unburned fuel is in it or something. I was looking at the design of them, it looks like the o2 doesn't even go into the tube like other cars, and there is only a very small hole for some of the fumes to go in, i assume

 

I dont see how it could cause any prob, engine is breathing much better. Just a thought.

 

You can also put on the type s primary cats. They have a lower cell count and should provide some gain. I believe a couple of members here have done this with some success.

 

huh, i have not heard of this yet. i would love to see what those members think about it...

 

I would rather invest in PCD than type s cats, unless you live in CA

 

Ok; so i shall go with the precat deletes. lol

 

OEM UA6 Primary Cats = 900 Cell/Inch
OEM UA7 Primary Cats = 600 Cell/Inch
OEM UA6/UA7 Secondary Cat = 300 Cell/Inch

 

^ first tl with precat deletes... I guarantee it rofl... friggin making me install them same day they came in