No Cats, OMG!!!!!!

[BigCarrot]

I took my converters and all three mufflers out today and put two Dynomax bullet mufflers in their place. HOOOOOLLLLYYYYY crap it's loud! It sounds like a freakin nascar! It sounds like a hog eating hickory nuts when it idles! Gotta love the lumpy 99 cam! I like it a lot, but I don't know how long I can take it. It sounds like a fireworks show when I drag it down to about 1800 rpms! I think it lost some low end torque, but it seems to pull harder on the big end. I sure get a LOT of attention when I'm cruising around!

 

[ElDiablo Viper]

I gained 7HP and 12TQ at the wheels. Make sure to install simms or you are down 30HP. Also VEC1 would hel to fine tune it.

 

[BlownViper]

Ipicked up almost 30 rwhp and 50 ft/lbs at the wheels with my 97

 

[BigCarrot]

I did the sims, I hope they are working right. Those things are a PAIN in the ace! The Corvette ones are a lot easier! Sean Roe, if you're listening. Those ****! I had a big *** of wires that I THINK are in the right spot, and two big boxes that had to go somewhere. Surely that design could be improved upon! Why not attach a plug to the end? Just food for thought. I'm buyin your blower asap! lol

 

[BigCarrot]

Ipicked up almost 30 rwhp and 50 ft/lbs at the wheels with my 97

WOW! That's a lot! You must have had some stopped up cats or something. If I gained that I'd be at 466/540! lol Don't think it gained that!

 

[ElDiablo Viper]

I did the sims, I hope they are working right. Those things are a PAIN in the ace! The Corvette ones are a lot easier! Sean Roe, if you're listening. Those ****! I had a big *** of wires that I THINK are in the right spot, and two big boxes that had to go somewhere. Surely that design could be improved upon! Why not attach a plug to the end? Just food for thought. I'm buyin your blower asap! lol

The sims fit perfectly in the frame. Two spots in the frame look like were made for it.

 

[BigCarrot]

Yeah, I foung those, but it says to keep it away from the exhaust. I did't know if they were heat sensitive or something. I just got frustrated with them. I'd be happy if they just had some plugs!

 

[ElDiablo Viper]

Now take the car out at night and go all the way to red line...back off the gas and see flame fly...VERY COOL.

See my Video with flames
http://forum.rallyfreak.com/zerothread?id=585

 

[Shelby3]

How do you handle the smog inspections in TX?

 

[viper spray]

No sniffer for inspections in Austin , just the cities that the EPA says have had too many days above a certain level of smog.

 

[BigCarrot]

I just go home to the folks' house and get ****** to do it. I say hi to uncle Jesse and Boss Hog on the way in and nobody asks any questions. lol I have old redneck friends that will pass anything I throw at them.

 

[Big Medicine]

Does it stink? I'm considering this w/ headers.

 

[monnieh]

ODBII just checks what the computer has for problem codes. No codes, you pass.

Pre 1996 I belive is ODBI and a sniff dyno is required.

 

[Viperfreak2]

What's a SIM? I still have cats, but nuthin else. Loud, hell yeah.

 

[BigCarrot]

Yeah, with the sims, which are 02 simulators, it will pass. It has a little bit of a gas smell, but it's not too bad. You can only smell it if you stand behind the car. It's MUCH louder without the cats. Almost gives you a headache, but it sure pulls on the top end!

 

[Viperfreak2]

Does this mean with sims, I can put an electric Y pipe at the back of the rockers and run one way through the back (stock muffler) and flip the switch and run sidepipes straight out??? I hesitated to do this because of the location of the O2 sensors.

 

[BigCarrot]

I believe you can. The cutout would just need to be after the first O2 sensors. I don't think these will work for the upstream sensors, but they might.

 

[GTS Bruce]

Syms from Jon B are plug in.Lift car and maybe take 5 minutes to install.No problems at all.Work perfectly Bruce

 

[BigCarrot]

***? Jon B told me he didn't sell products like that. He then proceeded to try to sell me some hi flow cats. That sorta irritates me! Sean Roe's may have been irritating to install, but at least he sold them to me!

 

[Vipermed 97.01]

How do you handle the smog inspections in TX?

I dont know about Texas but until about a year ago Fla had pretty strict emmission testing.90% of the Vipers leaving this shop including both of my own we would get so busy we would forget to reinstall the cats Not one failed test.and this is without sims.your Pcm will do its job of making the proper adjustments if it cant you will get a check engine light then you will need sims.even my 01 with no sims or cats passed with flying colors.we use to laugh at them first because they could never find the cats,i would explain that they were concealed behind the side sills.Then the supervisor would come out and say that the viper is the exception to the rule of actually visualising the cat."but trust me if he didnt have them it would fail"yea right.And ours was actually State run and controlled.

 

[BigCarrot]

LOL, I like it! Usually the guys working at a gas station aren't really MENSA material.

 

[carguy07]

Same here with the smog test. Numerous car with "empty" cats that passed with flying colors. One passed CA test with empty cat and an "off road" chip in it. Go figure.

 

[fearsuch]

so for a 2000 rt10 if I remove the cats will I need sims? and if I dont use sims will I loose power?

 

[GTSnake]

Big C,

How did you mount the Dynomax mufflers? Did you have to cut and weld to the existing 45 deg bend section? I'm thinking about doing the same thing since I have a restrictive Borla/Mopar muffler. Did you have a shop do it? I've heard that I need to find somewhere where they're experienced with stainless exhausts.

Thanx,

 

[BigCarrot]

On the SRT you'd need sims. I have a friend that did it. You will probably loose power without them, because the car goes into closed loop and richens it up way too much. It doesn't know what's going on, so it dumps a ton of gas to make sure it doesn't lean out. We cut the muffler and cat section out and mounted the Dynomax in it's place with about two feet of pipe behind it. We put a bend in the pipe to make up for the offset. Stainless is a little harder to weld, but not much. Any reputable muffler shop should be able to do it. Some places won't touch the cats though. There's your problem.

 

[ElDiablo Viper]

I dynoed my car w/o sims and I lost 30RWHP after the install of sims I gained back 37RWHP.

 

[GTSnake]

Big C,

I already have the RT cats on. Would the Dynomax fit behind the CATS in place of the muffler?

 

[BigCarrot]

Yes they will. A lot better flow, and better sound too!

 

[MbnViper]

I dynoed my car w/o sims and I lost 30RWHP after the install of sims I gained back 37RWHP.

hi ElDiablo, is -30RWHP with check engine light ? or no light ? no light here since i removed the cats,i have Roe sims but im waiting for the light to come on so i know my installation went ok.thanx

 

[RedEnuf93]

I have no cats, headers, 3" exhaust with side pipes and one Dynomax Bullet on each side.

The noise does not bother me, but the ears ringing all night does....

I drove thru New York, must have set off about 120 car alarms! Cool! I'll keep it this way a while, cannot hear wife nagging too well either!

Lauri