Jump to content
The mkiv Supra Owners Club

NO CATS


mrboost
 Share

Recommended Posts

I have asked this before, but just trying to get things straight in my head.

 

I want to remove both cats on my MKIV TT (95).  I not going to bother with cat replacements, I'm just going to chop them off and install some more stainless steel tubeing back onto the HKS Drager.

 

Now I believe I'm going to hit FC ?  I'm going to hopefully fix this with a jobbie from Mr Betts.  Can anyone see anything else that I should be aware off.  (NOT THE MOT_my mate mot's my car, NOT THE LAW_my car is to low for them to see+they have to catch me first+ they won't be bothered with my exhaust if they pull me, they are more likly be interested in my number plates and windows and funny blue lights underneath the car.)

 

Just anything to do with good old reliabilty, driveabilty, fc etc, etc

Link to comment
Share on other sites

Quote: from mrboost on 9:45 am on Jan. 9, 2002[br]I want to remove both cats on my MKIV TT (95).  I not going to bother with cat replacements, I'm just going to chop them off and install some more stainless steel tubeing back onto the HKS Drager.

 

 

Surely by the time you have made two short pipes and welded on flanges you may as well make one big one?

 

You could then keep the original cat assembly for MOT's, if not for you for the next owner.

 

regards.....

Link to comment
Share on other sites

Fit a boost gauge and an EGT gauge - keep an eye on both if you go above 1.4bar on stock T's your in serious trouble. 1.2 is still a bit high for standard fueling - might be worth investing in some uprated fueling....HKS AIC System? Or an Apex'i S-AFC.... the fitment of and FSE to raise fuel pressure could also benefit your higher boost.

Run Optimax or BP Super (IMHO BP SUL is the best SUL) + Optimax or Silkolene Proboost. Stock fuel map starts to run lean after 1bar....

 

Don't let you EGT's get above 940degC...have you got an intercooler? This would be useful to reduce the EGT's/increase power.

 

Hybrids would be a good idea as their efficiency range is normally around the 1.3 - 1.6bar range. As I understand it Hybrids will produce lower EGT's at a given boost due to efficiency gains...but it won't be lower by a lot!

 

Have you considered what your going to do come the MOT...??? ;) ;)

 

Only kidding,

 

What type of metal are you going to get your pipes made from? Chris Wilson has a kit ready to go which should keep boost undercontrol?

Link to comment
Share on other sites

Quote: from Phil Wall on 2:08 pm on Jan. 9, 2002[br]Chris W supplies a ring to put in cat free systems to help keep boost down.  I think it reduces the cross section to 2.5 inches in diameter.

 

He doesn't! I have never had a system that needed this except one "odd" one that seemed to make 22 PSI. It turned out to be hose lakage problems controlling the wastegate. Pipe sizes are configured to allow pretty safe boost levels without further restriction. A ring could be used to further limit boost, but so far it has proven unnecessary unles Brian Jackett ended up using one himself.

Link to comment
Share on other sites

Quote: from Phil Wall on 9:11 am on Jan. 10, 2002[br]Please accept my apologies Chris.

I must have misunderstood some previous posts.

 

No worries! Just don't want misinformation about them to spread ;-)

As far as I know only the one I mention above gave more boost than desireable, and that was a hose leakage problem (acting like a leaking wastegate).

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.