how much power does miltek high flow cat add?

[lask8ter134]

well i recently just purchased a miltek high flow cat and I am going to install it this weekend, I am expecting gains of at least 10-15hp and 15-20 tq. Does this sound reasonable?? and how much more gains is there out of a testpipe?

pros and cons too, because I know a testpipe is not street legal here in CA. Thanks

[RedS-line]

there was some tuner magazine that showed that a good high flow cat was almost as effective as a testpipe. however, gains on the testipipe were closer to 5-10 and a the cat was more like 4-9. If you make 10 hp you should be happy.

[golfvdude]

Did you buy the one in the classified?? That was an awesome deal. I figure since you have a reflash and such, it would warrant a greater gain than stock. I don't think that's out of the question but In either case, there should be an improvement. I would say more like
5-8hp and 10-15 tq. Either way, it's better than stock!

[QTC]

Someone dyno'ed their car before and after (w/ a Milltek HFC) and it showed 0 gains. However it does quicken up the response.