Has anyone use a catalytic converter 3inchs or more inlet pipe diameter not outlet,like SARD or Maganflow on a street car with 4inchs down-pipe and 3,15inchs TOP Fuel cut back exhaust system.This compo is to be done due to strict rules of the police in my country.Note that the car will have on street approx.700hp.On dyno the exhaust will be removed for up to 1000hp.

Do you think this compo is safe on street??I talking mostly about back fire and sound...What do you suggest with what supporting elements??

 

I think you're going to have a tough time finding that particular combo...... but to answer your magnaflow high flow cat question: Yes, I've used them and have no complaints. It's a very small cat-con and a true 3" inner diameter. I did have one fail on me after 4 years, the material inside broke apart. Still, I passed emissions all the time, but that doesn't necessarily have to do with the cat, rather the condition of the cars running at the time.

 

Randomtechnology sells a universal 4" catalytic converter. Wouldn't it be better to get a custom made 3"~4" exhaust instead of Top Fuel 80mm setup?

 

I was going to make a custom one but i thought that ready brand exhaust would be better and had smoother and not very loud sounds.If i put that Random catalytic converter won't cause any back fire on the street?Will it make the exhaust sound smoother?

 

The Top Fuel 80mm is not quiet. A 700~1000hp setup with 272+ cams is not going to ge quiet. Trust, HKS, Kakimoto, Blitz and a quite a few more Japanese companies sell 80mm exhaust systems that are 94dB complient but that was with normal cams and not highlift long duration cams.

Research silencers and submufflers (resonators) so you can make a good purchase. Buy those two items and then take them along with the catalytic converter of your choice to a shop that uses mandrel bent piping. Unless you request Titanium turbing you should be able to get a good custom fit exuast for $600~$800.

 

I think you are wright,i will buy a catalytic converter but 3,5 or 4inchs pipe diam?My down pipe will be 4icnhs.And make a resonator 3,5inchs?All i can do custom but the muffler i have search and can not find anything.Someone told me about RC muffler 4inchs but usd800..tooo much.Are you sure in the end that will not cause ANY back-fire that is my main problem??

 

Proper tuning will solve the backfiring. I will try to find some links to exhaust parts for and post them later.

 

try contacting horsepowerfreaks.com looks like they may have a 4inch inlet pipe muffler. they use it for their 3.5 inch tbe http://www.horsepowerfreaks.com/pric...t/EVO8_Goliath

 

Thanks i tried days ago and they told me that mufflers and catalytic converters are not in stock nor that they will have and recomended not to use any of those bigger that 3inchs pipe on street.But exept that i found that they are a very good company and they get back to everything you ask fast.