Hey guys i plan on opening up my exhaust front to back on my JDM FD with a racing beat catback, bonez highflow cat and the HKS Downpipe I already have an aftermarket intake system (pettit)and im a little worried i might start to see some boost creep.

So i was just wondering with the high flow cat if i have created enough restriction to avoid seeing boost creep. I dont really want to port my waste gate as i see myself going single turbo in the near turbo not to mention i dont know of any rotary experienced mechanics to do the job (not saying there isn't any around me).


My next mods are PFC, Datalogit, Wideband then upgraded rad
Reliability mods have been done minus Silicon hoses

Thanks for your time your shared knowledge is greatly appreciated

 

You can probly search as a lot of people have written more in depth descriptions about it. I would wait til you get a power fc before you throw the high flow cat on. You'll probly see an obvious increase in boost from the down pipe alone

 

With similar bolt ons in my R1 when I was just starting out,Ii didnt see any noticeable boost creep. All the same, I'd take it easy until you have Boost controller PFC. Its just good insurance as none of our cars will always behave the same even with exact bolt ons

 

A boost controller is only good at controlling boost SPIKE. It doesn't nothing for boost CREEP. Spike is from opening the intake. Creep is from too little back-pressure... i.e. too much exhaust volumn which overwhelms the wastegate.
With that settled....I run a Bonez hi-flow and have no issues with creep. IMO it's generally accepted that a hi-flow cat does retain enough back-pressure and you shouldn't have an issue.

 

As always, Sgtblue is correct ...stated boost controller and PFC as items on the list to get to increase margin for safety as he ventures out in mods if he is worried now about boost issues.

I guess I should have been more clear as I assumed OP would understand.

 

Sorry for bumping an old thread, but this one is the most relevant to what I have going on. The above posters stated that a hi flow cat would not cause boost creep issues, but I am creeping with a high flow cat.


1993 FD Touring
Mods: HKS DP, Bonez Hi Flow Cat, HKS Cat back, HKS TwinPower ignition, Greddy SMIC, Stock modified airbox (bastard air mod), HKS Bov, Stock Sequentials, Apexi Power FC, 99 spec Ypipe, Fluidyne Aluminum Radiator.

It wants to creep close to 15psi. If I let it, then it will hit fuel cut.

Perhaps it is the colder weather causing this?

Thanks!

 

Are you sure its not boost SPIKE? You've opened the intake with the cheap-bastard mod, Efini 'Y' pipe and SMIC and you don't have a boost controller in place....at least you didn't mention it in your mod list. With the particularly cool/cold weather, SPIKE would be my first suspect. A manual or EBC is probably in order.

 

Hmmm I'll give that a shot. Main reason I think it's the high flow cat is because I didn't have issues until I installed it.

 

General rule of thumb is that no boost controller can lower boost past what the wastegate will naturally achieve. So a wastegate actuator with a 10 PSI spring will always have a minimum pressure of around 10 PSI regardless of what lower pressure the controller is set to.

 

Yep I had boost spike for sure. The Manual boost controllers per this write-up solved all my problems. Thanks guys!

https://www.rx7club.com/3rd-gen-arch...attern-242324/