Riptide

Took me a lot longer than it would have any of you I'm sure. Getting the injectors out was a pain in the ***. Took a while to clean up the area around the intake ports on the motor. Drove the car this morning to test. No CEL, seems to run fine. I can't obviously hear any leaks although I'm a newb so I may not notice one if it's there.

My impressions so far. The car feels softer down low. If I'm in 2nd gear lower in the revs it just doesn't have the snap it did before when I'd go WOT. I'm sure there are gains up top but it's a little harder to feel a small high end gain vs. a small low end loss. I'm guessing the fact I'm using an email tune might be responsible for this. Brenspeeds tunes are supposed to be good though so I'm a little puzzled.

Kind of a yawner if you ask me. I sure hope the longtubes don't disappoint like this, especially @ the price they want for them.

kingsofcrunk

I still don't understand how you could feel a loss of power by adding less air restriction to the engine. I mean, maybe you just think you lost power? When I first got my long tubes, I thought I lost power. But when I started timing my runs, I saw noticeable gains. Now I can def tell my car pulls stronger with them. Idk, I just don't know how power would be lost.

howarmat

its not loss of power.....its loss of torq

jahudso2

In reality, a loss in torque always equals a loss in power at that rpm. If you loose torque at 2500 rpms, then you loose horsepower at 2500 rpms, because horsepower is just torque times engine speed divided by a constant.

The butterfly valves increase engine efficiency at low load and low rpms by increasing air velocity (bernoulli effect) and inducing tumble into the intake air which helps the air and fuel to mix better.

Taking the butterfly valves out increases the airflow at wide open throttle which increases the volumetric efficiency at high rpms and high load (WOT), but you are still losing mpgs and partial throttle torque in highway and daily driving.

I still haven't bought these yet, so I don't have any personal experience, but that is the theory behind them.

USAF in Germany

Any mod that unrestricts airflow and exhaust will cause a loss of low end tq but gain hp at top end of the motor's rpm range. A good tune, better if it's a dyno tune, is best to optimize the gains

howarmat

correct, which is why changin mufflers and going to an o/r pipe do the same.

And JD is right too, since hp/tq relate you lose power to

Riptide

I've been told that tuners now are able to compensate for this and I shouldn't feel a low end loss at all. I've read other threads where people installed these and felt no low end loss.

I dunno what to think.

howarmat

this is true....when doug installed and tuned them on his car he posted the results and there was no real loss down low. This was long ago when they first came out with the plates too. But just because it can be tuned out for the most part doesn mean it was. even car is different so it might work better on some and not others. its not just a box you check and say ok the tune will now compensate for the CMDPs and have no loses. you are changing several values depending on other mods you have on the car.

Riptide

AFAIK there isn't much I can do about this without putting the car on the dyno and tuning it. Assuming it's a tune issue. I'm stuck with brenspeed's email tunes right now.

I have a theory as well that people who do this mod by itself are more likely to feel a loss in the lower range. If you do pulleys at the same time then the power they free up would probably help cancel out any noticeable low end loss from the plates making it harder to feel that.

Fresh_GT

Hmm, I was about to buy some of these, but then I saw the FRPP intake, so I'm gonna wait for that instead. As far as LTs, when I did my LT Kooks and off-road H, it seemed to pull about the same, but then I realized it was actually pulling hard in 4th like it used to in 3rd. Now 3rd is over so quickly second used to be.