I just installed my Helix DP and Apexi catback. Initial fitment seemed great and the car runs superbly. Then during the initial testing I am hearing a grinding/banging when performing a normal launch (from a stoplight not racing or anything just letting the clutch out and proceeding forward). I did a search and it seems that one other person has had a similar problem. In my searching I didn't find any solutions to this.

Does anyone have a fix for this clearance issue? It seems that the DP is hitting the chassis, not the lower braces. I will have another look this evening after work but I wanted to first inquire to see if anyone has a fix for this.

Thanks
NR

 

had same problem with mine. I had verstion two. the reason you are hitting is when helix made the DP, they made it with the jap spec cat in mind which is about 1/4" to 1/2" smaller our than US version cat. I had to buy the Helix hi flow cat and now no more rattle. Hi flow cat was also a big plus on HP gain and no CEL. I hope that helps. Good luck. Peace.............

 

Had the same trouble as you with a Helix DP.

My solution: bought an Ultimate Racing DP.

 

my helix DP solution. no probs since.
https://www.evolutionm.net/forums/sh...ighlight=torch

 

I have an extra gasket that I will add on tonight.

Everyone,
Thanks for the input!

 

I went with an RT HF cat.

With the stock cat, I used an extra gasket and it helped, but did have slight rubbing. Not an issue anymore.

Take care,

FB

 

would the cat delete/hi flow cat solution only work with helix products, or would a perrin cat delete work as well to get rid of the rubbing?

 

I too had this minor problem as well, but I was able to swap out the stock dp hanger bushings with the Kartboy units, and now the DP wouldn't even move to cause rattle. I highly recommend using Kartboy harden hanger bushings to go with the DP!