lets talk dyno graphs
6th Gear Member
Joined: Oct 2006
Posts: 10,551
From: Texas
Your heads are the limiting factor.. not the intake. The intake is one of the best there is for the 2vs. The only reason to swap it out is to have a more sturdy intake for a lot of boost/nitrous.
The power you gain/lose with an aftermarket intake is not even worth swapping out unless you crack yours and want a new one.
The power you gain/lose with an aftermarket intake is not even worth swapping out unless you crack yours and want a new one.
4th Gear Member
Joined: Sep 2009
Posts: 1,481
From: NC
I cannot say if it is the Bullitt intake (I have a 2001 Bullitt) on my car or not, but I also have full bolt ons, including long tubes and my motor hits it's peak HP at ~5800rpms and drops only ~2-3HP between 5800 & 6200rpms. My heads are bone stock. Before the cams and long tubes, it peaked at 5100rpms and dropped off 7 HP by 6000rpms. The difference between stock cams/exhaust manifold and new cams/long tubes at 6000rpms is ~57rwhp. The gains up higher in the rpms (above 4500) are VERY significant.
Every dyno will give different results so be careful about trying to directly compare other people's numbers to yours.
Every dyno will give different results so be careful about trying to directly compare other people's numbers to yours.
Last edited by TRUEBLUE3934; Jan 5, 2010 at 11:38 AM. Reason: add comment about my heads
6th Gear Member
Joined: Jan 2007
Posts: 5,884
From: MI
I cannot say if it is the Bullitt intake (I have a 2001 Bullitt) on my car or not, but I also have full bolt ons, including long tubes and my motor hits it's peak HP at ~5800rpms and drops only ~2-3HP between 5800 & 6200rpms. My heads are bone stock. Before the cams and long tubes, it peaked at 5100rpms and dropped off 7 HP by 6000rpms. The difference between stock cams/exhaust manifold and new cams/long tubes at 6000rpms is ~57rwhp. The gains up higher in the rpms (above 4500) are VERY significant.
Every dyno will give different results so be careful about trying to directly compare other people's numbers to yours.
Every dyno will give different results so be careful about trying to directly compare other people's numbers to yours.
4.6L Section Moderator
Joined: Nov 2007
Posts: 10,286
From: South Central PA
The bullitt manifold does help. Not sure how much. But usually people that dont have bullitt mustangs wont do a bullitt manifold upgrade just because they are expensive and you can get upgrades that are cheaper that will do the same thing. But yea, your bullitt manifold helps your cause.
4th Gear Member
Joined: Sep 2009
Posts: 1,481
From: NC
Sorry, I forgot to mention that I am running the HiTech Stage II cams.
I wish I had PP my stock heads while I was doing the cams, but that is water under the bridge now. A set of the new Trick Flow heads would be extra sweet. Maybe I'll save for a set of them next.
Yes, area under the power/torque curves are the most important! If you have to give up a bunch on low end power to gain a little peak power, it is not worth it for a street driven car. If you can make gains under the entire length of the curve, you have really done yourself some good. The cams and long tubes added a very significant amount of area under the curves.
I wish I had PP my stock heads while I was doing the cams, but that is water under the bridge now. A set of the new Trick Flow heads would be extra sweet. Maybe I'll save for a set of them next.
Yes, area under the power/torque curves are the most important! If you have to give up a bunch on low end power to gain a little peak power, it is not worth it for a street driven car. If you can make gains under the entire length of the curve, you have really done yourself some good. The cams and long tubes added a very significant amount of area under the curves.
6th Gear Member
Joined: Jan 2007
Posts: 5,884
From: MI
People get all caught up in the peak dyno numbers too much. This is a big mistake...especially with cams. The best performing cams are ones that have the broadest hp and tq curve. That's why most stage 1's (and some stage 2's) will perform best with stock heads, regardless of the peak numbers.
3rd Gear Member
Joined: Jan 2009
Posts: 570
From: Florida
you can't compare 2 different cars on 2 different dynos. Hell you can't compare the same car on different dynos. Dyno #'s can and will get manipulated by tuners to make a "happy customer". We all know that a Mustang Dyno reads higher than a dynojet but my car put down about 15 more rwhp on a MD than a DJ (320 vs 306), once again proving that dyno #'s don't mean squat.
The intake is part of the problem but the stock heads don't help. My car with ported heads made max power around 6k rpms. Ask yourself how how do you really want to rev that engine? Keep in mind that max power isn't where you always shift at. Everyone has their own opinions and research but from what I was told you want to shift at 10% over max hp. That may or may not be correct (probably not which explain why I'm so slow
), so that would put me at 6600 rpms, IMO that's plenty high, an aftermarket intake would put it closer to 7k.
Have you ever ran your car at the track with the cams? If so what did it run? the MPH should be the true way to tell the cars power. BTW my car on the DJ on a 100 shot made ~400rwhp (that to me is way off considering it trapped 120.3 mph) Which I think is what JayC traps on a 150 shot and he's over 450rwhp. On that same DJ I made 306rwhp NA and trapped 111mph, IMO that MPH is a tad high for 306rwhp. Hope I didn't confuse you just trying to show that you shouldn't put much stock in dyno #'s.
The intake is part of the problem but the stock heads don't help. My car with ported heads made max power around 6k rpms. Ask yourself how how do you really want to rev that engine? Keep in mind that max power isn't where you always shift at. Everyone has their own opinions and research but from what I was told you want to shift at 10% over max hp. That may or may not be correct (probably not which explain why I'm so slow
), so that would put me at 6600 rpms, IMO that's plenty high, an aftermarket intake would put it closer to 7k.Have you ever ran your car at the track with the cams? If so what did it run? the MPH should be the true way to tell the cars power. BTW my car on the DJ on a 100 shot made ~400rwhp (that to me is way off considering it trapped 120.3 mph) Which I think is what JayC traps on a 150 shot and he's over 450rwhp. On that same DJ I made 306rwhp NA and trapped 111mph, IMO that MPH is a tad high for 306rwhp. Hope I didn't confuse you just trying to show that you shouldn't put much stock in dyno #'s.
This gets my vote for the best post of the week award (seriously)
I have seen the same car make 268RWHP on a Dynojet and near 300RWHP on a Mustang Dyno and turn 110.5MPH at the track (which puts the truth somewhere in the middle).