I'm thinking of putting on a Flowmaster or Magnaflow on my 01 Screw to up my HP. I stopped by the local muffler shop to get an estimate. The guy there said to keep the factory setup. He said the OEM equipment was pretty good and that he's installed Flowmasters and they haven't helped with with HP. In fact, he said they've hurt HP when towing. Not sure what to do now?

 

OK, no they dont hurt when towing. I have a v-6 and tow a 20ft bass boat with a 200hp engine. After getting my exhaust, it helped my hp and my low end, now what you might want to do is keep the stock pipes, change out your muffler and just add a tip IF they are going to keep your stock size pipes and it will save you some $$$. Otherwise go with a whole system. I have the flowmaster 50 series delta flow, and it has a nice sound even on my ***** v-6. I had the 40 series but it was WAY to loud inside when towing. If you tow often, then go with the 50 series delta flow and you will be happy, you will feel increase and 1-2mpg better depending on if you drive the same or not. Also look into an intake system, like a K&N generation 2 system (since you have a screw which has a v-8) and that combined with the intake will help a ton towing! Hope this helps, e-mail me if you have any q's sdf150guy@sbcglobal.net

 

Pudidog,

Don't know how well you know this guy, but does he have any Dyno sheets to back up what he is saying ?

Maybe I have my dyno sheet wrong, but what I read on mine and others :
The HP is par with stock when driving, but when towing the HP is reduced ??
WTF is that, how is he doing a Dyno pull with towing simulation ? The Dyno pull on an Auto is for 3000 RPM and above, if he is taking a dyno run and simulating weight by applying the break, I don't know how valid this is ( cause the truck to down shift when the load is applied and having a shift on a dyno pull is not something you do ).
Also HP is HP, the engine is going to produce X amount, weither it is towing or running empty. I don't know how HP is removed from an engine while towing, that is a strange one to figure out, if I have it all correct when looking at things. HP and TQ produced by and engine are there, not added and removed when doing things. This is one reason you get a truck weight before the dyno pull, so you know how much weight the drum should have, and run as close to 1:1 in the gear position as you can.

Maybe the problem he has had with systems is the way he bends pipe, and jacks up the xhst gas flow. I tried 2 muffler shops before I gave up and went to a speed shop and had them do the work on my duals, they under stand before and after with a dyno. The muffler shops told me all sorts of BS about duals, and "computer" problems and CELs being set after doing duals, and the gain is not worth the money ( ?? ).
Sounds like he is doing SOTP dyno work at his place, I'd find another shop to talk to about it, rather then listen to him with what sounds like BS to me. Either that or talk with Mike T and ask him.

Maybe I'm all wet on this, but I thought I had it figured out. If someone can tell me how HP is removed from an engine during towing I'd be more then willing to listen.

Talk with a tuner on this topic, and ask about cat backs, and duals to see which you want to do, at what cost. Also try to check around for another shop to have the work done at, this one shounds like he is good for swaping mufflers on soccor mom's mini vans, and that is about it.

 

Flowmasters can reduce torque a bit on our trucks that is why the Magnaflow and Borla are better systems for our trucks. I say go with the Magnaflow you will be much happier with it in the long run. I myself prefer and will only use Borla on my vehicles and have been using it since 1988 but have heard nothing but good things about Magnaflow which is very simalr in design to the Borla.

This is strictly my personal choice.

Richard D.

While your here check out my gallery:
https://www.f150online.com/galleries....cfm?gnum=2479