Jump to content

3 Inch Exhaust And No Cat. Will I Get Turbo Overspeed Issues?


patrol_maverick

Recommended Posts

  • Member
  • Member For: 12y 8m 3d
  • Gender: Male
  • Location: Taree NSW

I'm putting a BA Barra turbo into a Nissan Patrol. I have a factory FG manifold and dump pipe fitted, and will have a 3 inch exhaust fitted which wraps around under the sump, then will run down the passengers side of the car.

My concern is, if I have a free flowing muffler and no cat, am I going to have turbo overspeed/ overboost issues? I don't really want to throw more money at it and get the gate ported. Should I expect to have issues with it before/ after I get it tuned? I'm not chasing huge power, it's a Patrol, not a drag car ;)

**My apologies if this is in the wrong section. I wasn't sure if this should be in the turbo or exhaust section.

Link to comment
Share on other sites

  • Member
  • Member For: 18y 9m 4d
  • Gender: Male
  • Location: @ my laptop

overboost depends mainly on what your target boost level is, if you want to run 12 psi and can get 12 psi with some control over it, it is fine, but aiming for 12 and having 14 at 0 duty cycle is really an overboost situation and will be worse with cold air, but there are many cars running around like this and they just claim that's how it's tuned for

  • Like 1
Link to comment
Share on other sites

  • Member
  • Member For: 12y 8m 3d
  • Gender: Male
  • Location: Taree NSW

More than likely you will have issues

Can you elaborate a bit more?

If I were to get it tuned at 10psi, it should stay pretty stable shouldn't it?

Can't excessive exhaust flow/ lack of back pressure cause boost spikes? I thought that was the reason for porting the waste gate- to better balance the flow between the gate and turbine.

Link to comment
Share on other sites

  • Moar Powar Babeh
  • Lifetime Members
  • Member For: 19y 5m 8d
  • Gender: Male
  • Location: Perth

Your likely to have boost control issues with no cat.

The stock Ford intake and exhaust until used back pressure in the exhaust to prevent boost spikes/creep with the small stock gate.

I think your exhaust will be free flowing enough to cause issues.

In all seriousness if your skills enough to carry out the engine install your skills enough to have a crack at porting the turbo. There's plenty of info on this site and on the net to guide you.

Link to comment
Share on other sites

  • Silver Donating Members
  • Member For: 19y 2m 13d
  • Gender: Male
  • Location: North West Hot Hell,VIC

Ralph is right about porting the turbo yourself , but if you are not chasing big power why not just put in the std cat and not worry about over boost .

Link to comment
Share on other sites

  • Member
  • Member For: 12y 8m 3d
  • Gender: Male
  • Location: Taree NSW

Almost anyone can do the port.

how well?

have seen some jobs from specialist that did not work very well when combined with free flowing intake and exhaust

What was the reasons for it not working very well?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
  • Create New...
'