Ditto, you will NOT get 30 hp out of longtubes. Low 20's is more like it.

 

Ok, well 20-25 is not bad I guess for 1100 bucks, just not enough gains there for the MAC system.
Stainless is the best, then ceramic coated right? what about wraping the headers to reduce under the hood heat? or is that old School? LOL
I have been out of the performance market for over 25 years so I am a bit taken back with all the new stuff.

 

I've been researching this quite a bit, and talked to several tuners that most of us are familiar with here on the forums. ALL of them said that HP gains on long tubes for cars WITHOUT a power adder are way inflated. While torque often goes up 12-15ftlbs, HP rarely exceeds 10-12 HP, and one said the usual gains are 8-10hp. I was stunned, as it just didn't seem to fit the collective wisdom. There are a LOT of reports from owners stating 20+hp, but so far I haven't seen a dyno before and after with JUST the longtubes. Most folks have added something else, like the CAI or UPDs.

I'm not saying folks are exaggerating, but I'm getting a bit suspicious that noone's got evidence, other than the posted sheets from the manufacturer. In MM&FF this month, they saw a 1hp gain after adding longtubes, although the torque went up a bit. When I added cams, I lost nearly 10ftlbs of torque, and had been thinking about LTs as a way to gain some of that back.

Not trying to incite anything, but I had cash in hand ready to purchase longtubes and dump my shorties, but the research just isn't backing things up. I went through the same thing with cams, listened to the conventional wisdom instead of my tuner and a few other aftermarket shops that I called, and got 10 horsepower less than ALL the claims out there. Obviously I'm a bit gun shy now. Anybody got a before and after dyno sheet with just the longtubes?

John

 

I hear it's a bad idea and that if you want heat reduction coated is the way to go.

 

I talked to Brenspeed the other day and they said people typically see increases in HP of about 10-15. This may have only been for catted midpipes, since that is what we had been discussing.

Also, Mustang Enthusiast magazine did a before and after dyno of a car with an intake, tune, and catted headers which showed an increase of 40HP and 35 ft-lbs. General consensus is that intake/tune is good for 25 HP, which would indicate the catted headers freed up about 15.

Also, isn't it true that the PEAK horsepower may only increase by a bit, there will be increases throughout the RPM range that won't effect the peak HP, but will help acceleration considerably?

 

Your last point is the more important one, and you are dead on: the increases throughout the RPM are easily measured gains at the track. That's why despite the dearth of "facts" regarding peak HP (I get Mustang Enthusiast but don't recall the article mentioned. Month/year of that issue?), I'm still considering longtubes to help get me into the mid-12s without a power add. I can use a few horsepower across the board, and especially the torque. My peeve here is that I read some of the claims but can't back them up with some kind of measurement. It's my hard earned money, ****it!

The only thing left really, beyond the LTs, are ported heads...but that's another thread...

John

 

Jwgroovin,all I can say is with more practice at the track,and using track tips from frequent drag racers on this site,you should hit high 12's using your current combo. LT's and CMDP's will bump you to mid 12's. Add Heads-then low 12's. Maybe 12 flat with some serious suspension work and weight loss(a-arms,k member,tubular rad support,lca's,uca's,anti squat's,etc).

 

tape also holds moisture and will help rust occure

 

Also doesn't allow the headers to expand and move around as they heat up. I suspect the bigger issue might be the elevated temps(compared to unwrapped exhaust) the headers subjected to while wrapped, compared to say a cast exhaust manifold, you are talking pretty thin stuff that is repeatedly heated and cooled and gets brittle over time. Coated headers can expand without being constrained by a wrap and the metal is further protected from the higher than normal exhaust temps because they are typically coated inside and out.