hi guys,
i need to restrict some the smel and niose on my fd. now i run 3" dp,mp and greedy catback.
what high flow cat do you suggest?
i heard good things about bonez and i would be hapy to hear some comments.
i do not run the air pump. does it mater with the bonez?
thanks!!

 

I've been happy with the Bonez on my car. It's over 8 years old but still in good shape. Two of those years have been without an airpump and it doesn't seem to be affected. And I'm on the stock OMP.

 

Hey SummitRacing sell metallic cat that are 3 inch, since u don't have the air pump, just buy those cut your mid pipe and weld it on, it suppose to flow about 50 more than hi-flow cat and cost $130 or less, I believe those cats are the same cars smb use for thier cats which cost around $600 plus shipping from Aussie.
Khris

 

That's good news to me! How many miles are on it? I just bought a Bonez unit a few months ago. I had a HF cat from Gotham racing(not sure of the brand, but it is definitely different than the Bonez). It fell apart after 5 years and about 10K miles. Stock OMP, Pettit Unlimited ECU@ 15psi(twins) FWIW.

 

Almost same reply, Bonez hi-flow cat, about 3 years, no airpump, stock OMP, seems to be just fine.

 

It was on there when I bought the car, but at least 48,000 total. About 10k of that without an airpump.

 

Interesting... I've been looking for someone who was making more than 300ish whp with stable high rpm boost with a high flow cat. I have been running a Bonez cat for some time and think I may have a clogging issue... I made a thread about it. THREAD LINK

 

hi,
thanks for the replies.
it seams that most of you like the bonez. is there any WHP restriction with the bonez?
thanks

 

Yes, compared to a midpipe there is a restriction and reduced max power. Any catalytic converter will result in some restriction to the exhaust flow. That's not necessarily a bad thing in terms of preventing boost creep. The trick is getting a cat that is effective and stands up to the heat of a rotary.

 

thats why i am asking your opinion. i want to make sure i do not buy the wrong cat.
can you please give more info about boost creep? what is and when appears?
thanks!!

 

Removing a catalytic converter (installing a midpipe) usually in combination of a higher flowing cat-back system can result in too little back-pressure. That condition can overwhelm the stock wastegate. The surplus flow will then be forced to exit through the turbines, creating an unintended increase in boost pressure. That's called Boost Creep. Too much of that can cause a lean condition and detonation.
Porting the waste-gate to increase it's ability to handle the flow, or re-introducing back-pressure into the exhaust (via a cat) is traditionally the only way to control boost creep. On stock twins, the wastegate is internal and requires removing the turbos to access.

Don't get it confused with boost Spike. While both can lead to detonation, Spike is caused by opening up the intake side and can be controlled by a boost controller. Creep is from opening the exhaust side and is unaffected by a boost controller.

There are probably better, clearer explanations than mine available through a search.

 

This sounds like a great option.

 

I've used both the Bonez and SMB Cats on my car and both are quality products. My car does make a noticable amount more power with the SMB than the Bonez, however, the Bonez is much quieter.

 

bonez hf cat on my car. works great, no smell and passed california smog. fitment was great with my hks dp and greddy catback exhaust. bolted right up.


Jeff

 

thanks guys!!
i will try to find more info about the smb.