horsepower for less $

There are plenty of us that have swapped it in and have noticed an increase in performance. The smooth turning, equal-length runners and bigger volume are clearly superior in design.
 
waking this thread up again.... anyway this article http://www.jpmagazine.com/techartic...iter_engine_myth_busting_true_lies/index.html explains that a newer intake manifold actually will reduce hp due to loss of air velocity

I gained 2rwhp/4rwtq on the dyno with the '01 XJ intake swap on my 4.6 stroker, with a ~5rwtq gain from 1500-3300rpm. Gas mileage also improved ~1mpg.
The '99+ intake has a much larger plenum but smaller cross-section runners than the earlier manifold. While HP gains may be small, the increase in TQ lower down the rpm range is noticeable.
 
well my thinking of why it helped you is probly because you have a stroker and can actually use that larger displacement of air in the manifold. im not saying the difference is bad at all, every couple hp/tq counts so if it would help me id do it too. its kinda same concept as a tb spacer and everything else stock, it does nothing because the factory setup can already pull in as much air as it needs to use therefor it gives it the ability to pull in more even though it wont use it. from what they found on a stock 4.0 i'd stay away from the swap, in ur case i would also swap it in for sure
 
What everyone gains is going to be different. The conditions are always different. I have dynoed cars at 630 in the morning and then dynoed them at noon and seen a 15hp loss. Air temp is always a factor. This mod has been done and dynoed "enough" times to see improvements on the majority of people's rigs.
It always depends on how much its worth to you. Is 3hp/5ftlbs worth 50 bucks? MAYBE. What if the only one you can find is 100 bucks? Is it worth it now?
 
I have dynoed cars at 630 in the morning and then dynoed them at noon and seen a 15hp loss. Air temp is always a factor.

The dyno is supposed to correct for barometric pressure, air temperature, and humidity (usually to SAE standard on most chassis dynos). I think you're looking at raw uncorrected numbers.
 
The numbers out of a Dyno are open to discussion. Yes, they will give you a corrected to Sea Level/Standard Atmosphere/Humidity HP/Torque values which is really nice for comparing apples to apples. However, here at 7,000' altitude what I want to know is what do I really have to work with. Sea level numbers are sort of silly really...

The Golan Stroker I put in my 97 back in 2000 was rated at 300hp on the Golan Dyno. Sea Level. Here? Not so much. Unless you are running forced induction (and even then) altitude robs power.
 
The dyno is supposed to correct for barometric pressure, air temperature, and humidity (usually to SAE standard on most chassis dynos). I think you're looking at raw uncorrected numbers.
Ok, I probably am looking at the uncorrected numbers, but that doesnt explain the difference in power when nothing changed on the vehicle. Ive seen it happen more then once too, but hey one time it was because some jackass left a bottle of co2 opend in the dyno room after disconecting a halo sprayer. that really threw us for a spin until we walked out there and realized the cars just sucking in the co2.
 
Ok, I probably am looking at the uncorrected numbers, but that doesnt explain the difference in power when nothing changed on the vehicle. Ive seen it happen more then once too, but hey one time it was because some jackass left a bottle of co2 opend in the dyno room after disconecting a halo sprayer. that really threw us for a spin until we walked out there and realized the cars just sucking in the co2.

Nothing has to change on the vehicle to provide different dyno numbers. Temperature, humidity and barometric pressure all have an effect on horsepower and torque.

As you said, you dynoed in the morning (low temp) then again at noon (high temp) and saw a power loss...
 
However, here at 7,000' altitude what I want to know is what do I really have to work with. Sea level numbers are sort of silly really...

Yeah, if you're living at high altitude they're not much use to you. The important thing to remember is that the dyno should be seen as a tuning tool rather than looking at the absolute numbers for bragging rights.
Just use the same dyno before and after each mod (preferably under similar weather conditions to minimize any difference in correction factor) so you can make an apples-to-apples comparison. That's what I did with the '01 XJ intake swap.
 
Dino,
You are correct that the BEST use of a dyno is for tuning. Way back before the dawn of time (circa 1973) I built up a 2 litre Triumph 6 cylinder into a 2.45L. Three Weber DCOEs using the British Leyland S-5 LeMans cam. Used the dyno at the BAP-GON. to get the Webers correct. Anyone that has ever attempted to tune Webers will under stand. Between idle jets, emulsion tubes, main jets, air bleeds.... Well you get the idea. At the Time, provided you were willing to accept "used" parts, BAP-GEON would trade out the as shipped parts for the ones needed to set up the carbs provided it was done on the dyno. Made for a relatively quick setup. End result? 256hp. Not bad for under 2.5L.

Of course, this was done in Sacramento. Elevation 20'...
 
What everyone gains is going to be different. The conditions are always different. I have dynoed cars at 630 in the morning and then dynoed them at noon and seen a 15hp loss.

The dyno is supposed to correct for barometric pressure, air temperature, and humidity (usually to SAE standard on most chassis dynos). I think you're looking at raw uncorrected numbers.

Ok, I probably am looking at the uncorrected numbers, but that doesnt explain the difference in power when nothing changed on the vehicle.

Nothing has to change on the vehicle to provide different dyno numbers. Temperature, humidity and barometric pressure all have an effect on horsepower and torque.

As you said, you dynoed in the morning (low temp) then again at noon (high temp) and saw a power loss...
CHERBEAR, look at what dino said.
 
At the end of the day, I was very happy that I swapped in the newer intake. It also helped that I got it for only $53. The HP/TQ gains were small but just enough for me to notice a subtle improvement by the SOTP. More importantly, I was impressed with the ~5% improvement in gas mileage so it didn't take long to recoup the cost of the intake with the fuel cost savings.
 
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