HP gain from MRT catted h-pipe?

Discussion in '1996 - 2004 SN95 Mustang -General/Talk-' started by mjh78, Jan 22, 2008.

  1. I have a Mac ss catback and jlt rai on my car. The catback I did not notice or expect a hp gain. The RAI I actually did notice some more pull on the top end. How much of a gain can I expect from a MRT catted h-pipe? The stock midpipe with those cats seems to be one of the more restrictive bolt ons on the vehicle. I would think a new h-pipe would offer a decent HP gain. Am I right?
  2. You are correct sir....... My last mod was a bassani x w/cats.
    It really brought my other mods to life. :hail2:
  3. I can hardly feel exhaust horsepower from my Bassani X. Plus, it's torque that you feel, not necessarily horsepower.

    As Shelby says, horsepower sells cars, torque wins races.
  4. love the quote. So you felt a good increase in torque with your midpipe?
  5. with a catted midpipe maybe 5-7 rwhp at the most, go cat-less and you can gain over 10. You're going to hear about 50 different opinions on this...
  6. :Word: A midpipe w/o cats will def net you a little more than a catted midpipe, but don't expect a tremendous amount.
  7. You gotta go WOT sometimes if you want to feel the difference Granma.:rlaugh:
  8. larger exhaust is the process of increasing flow (by decreasing resistance to flow), flow is mostly restricted (save for poor manifold scavenging) when it's at the upmost capacity, i.e. high rpms. Less restriction up there means more hp, i don't know what you guys are talking about mainly tq gains. Only reason you see more tq in an H pipe over an X is cuz the x flows better, the restriction of the H is causing more backpressure which low rpm tq appreciates.
  9. You will fell a little difference with a new mid pipe. I acutely had the same setup as you (mac ss catback and the MRT catted H pipe). It is a great combo and sounds amazing. Though I no longer have the Mac catback, I’m even happier with the performance of the magnapacks with this mid pipe. You can’t go wrong with MRT. If you are looking for a X I would suggest Magnaflow catted X but I like H pipes myself.
  10. My car put down 275 hp & 294 ft lbs tq with a catback, MRT catted H, & a C&L 85mm untuned. With my mail order Xcal tune my car put down 289hp & 311 ft lbs tq. Im not sure how much each mod gave me, but I know my car is supposed to have 305hp & about 320ft lbs tq @ the crank stock, so I figured it wouldve dyno'd roughly 260-265 hp at the wheels bone stock.

    The MRT is excellent quality & it has a nice exhaust note, & the cats mellow out the tone a little, but I would say the high flows may rob only 5-7 hp, but its not anything u will feel. I actually just received my Mac off road H today from UPS, so i will be catless pretty soon....
  11. That's the lowest I've ever seen with those mods on a Mach, horsepower-wise anyway. It's normally right on 297RWHP. Maybe the dyno was alittle off, or maybe the conditions.
  12. Could be, or maybe my car is a lemon?? I dunno. The 1st time I dyno'd my car on a dynojet, it put down 287 hp & 292 ft lbs. I dyno'd it again on a different dynojet & it put down 275 hp & 294 ft lbs on a cold evening??? Both of these were @ ricer shops that dont specialize in mustangs, so maybe thats why, but I doubt it... My A/F ratio is kinda lean too, so that could be another reason??? I am saving up for a real dynotune as we speak, & installing an o/r H pipe, so i will have some new numbers within the next month or so....
  13. do mustang gt's come with stock h-pipe configurations???
  14. I'd say the first place you dynoed would have put you right where you should be with a tune and those mods. Right around 300RWHP.
  15. What are the plans for the MRT???
  16. Probably gonna hold on to it 4 a little while, but I will let u know if I decide to get rid of it....I have to modify my H pipe to fit the crossmember for my torque arm, & since I wanted to go catless anyway, I decided it would be better to modify a cheap Mac h pipe rather than cut up the $500+ MRT H.
  17. Your probably right. Well see when i get my car tuned for real....
  18. Yup.
  19. I honestly didn't feel a increase in torque with my midpipe. I'm sure a dyno run will show gains in HP and TQ, but I just didn't get a SOTP experience. :shrug:

    WOT are for losers ;)

  20. So all those mods you did are for show only...............:shrug: