jeff p

just installed my Bonez HF cat . took the car for a test drive and noticed some improvments.

(1) exhaust note is a little louder but nice deep tone with the trust catback and HKS down pipe.
(2) turbo noise is louder kind of a high pitch zing noise."must be spooling faster getting about 1/2 pound of boost increase, but no creep. just smooth transition". now have a 10.5 -8.5- 10 psi pattern.

install was nice and easy. no problems at all. one thing I did keep was the old air pipe with the check valve on the end so operation of the air pump would be stock. Thanks for the advice (rynberg) just use the supplied tube from rx7.com to attach it to the cat.

over all I love it . more power, quicker turbo spool, and no smell at all out of the tailpipe. just clear hot exhaust. even my stock cat had a little odor at start up but cleaned up quick. now I hope I can pass smog with it next year LOL.

Jeff

rotarymandan

iTrader: (15)

I was thinking about getting this cat too. Are you in northern Cali? I know that there is a shop around here who sells this cat, and he claims a 20whp increase over the stock cat. From your post it didn't sound like it gave a huge increase in power, but my question is: was it worth the cost? Thanks

adam c

iTrader: (2)

Sounds good Jeff . What were the costs for the cat and other parts?

moconnor

iTrader: (14)

I had similar impressions when I installed mine. Had a very small increase in noise and noticed a power difference.

A few weeks ago I swapped it out for an SMB metallic, which seems to flow significantly better - the car certainly pulls harder and is very loud under WOT (but only slightly louder than the Bonez at idle or cruise).

Used these are a pretty good deal, but if buying new it may be worth thinking about the SMB. Though, it is not fully clear the SMB (which also has an airpump attachment) will pass smog. I'll find out in August.

(BTW, I'm selling my Bonez for $150 - local pickup only.)

SINxSELEKTAH

iTrader: (2)

is this cat C.A.R.B. approved?

FDeez

As much as I'd like a metallic substrate cat, I'm concerned about boost creep with the stock turbos.

I'm running a Bonez HF cat right now and I passed smog last year.

jeff p

rotarymandan: I am in So. Cal. if you are going to buy one get it from rx7.com mine was $465.00 shipped with the gaskets and stud kit. plus I had mine heat treated for another $120.00 "nice upgrade". I would say the power incease was about 10 to 15 HP seat of pants dyno! but the turbos spool up quicker and the car responds so much better. I would say it well worth the money.


adam c: $465.00 shipped with the gasket kit. plus $120.00 heat treating with grey Ice 2000 degree coating. also your cheep bastard airbox kit works great with my mods and the smog man can't tell anything is upgraded.

jeff p

Senxselektah: I was told OBD 1 cars dont need a carb number for the cat and rx7.com said its never been an issue with smog and a lot of people pass without any problems.

moconnor: I would not use the SMB cat without a computer upgrade. I think its to much for the stock ecu to handle. but I was told it flowed better than the Bonez. but for the street the bonez is the best unit to buy.

FDeez: glad you passed smog. I hope I have the same results. my exhaust is very clean right now. just clean hot air out of the tailpipe can't smell any fumes at all

moconnor

iTrader: (14)

The SMB may be too much for the stock ECU. It definitely flows better that the Bonez - I got a 0.5 AFR increase from 4.5-6.5k rpm. Strangely, the AFRs were the same above 6.5k rpm but that may be because of the small SRM intercooler than I am using. I will be installing an M2 large this weekend, which should help high rpm airflow.

However, given the closeness in price of the Bonez vs. the SMB new (I had assumed that a new Bonez was only $300 or so new), the SMB is arguably a much better choice for someone with an upgraded ECU. It is perfectly streetable (only very slightly louder than the Bonez at idle and at cruise, though it roars at WOT).

Only caveats would be possible creep (I got some creep at 13 psi, none at 12psi) and its unknown emissions status.

rynberg

As noted above, OBD-I cars can swap out cats with no issues. And your car should pass with the Bonez.

jeff p

Moconnor: I think the SMB is a great cat and a good choice if you have an aftermarket ECU... I am sure it flows better than the bonez. but I don't think it will pass a visual inspection with a downpipe in the Los Angeles area and the noise level will surely get you police attention on the street. so I still think the bonez is the best choice for us in Cali.

rynberg: Thanks for your help with the airpump tube. everything works great!

tphan

just sold mine...