Trading Torque for Horsepower. Intakes and powerbands
 

I've got about 1100 miles on the new 427 setup and I'm considering changing intake manifolds. I know the stock intake can support plenty of power. I think a member here has made 1700whp through it. However that doesn't mean all aftermarket intakes don't have their place.

I seem to have a plethora of torque, especially with the new 3.73 gear. I still drive the car on the street occasionally, and traction is still an issue. I have to drive with 12psi in the rear tires to get any traction at all. Only after a burnout can i do 60 rolls at full power.

I'm going to use my last dyno chart for a visual aid. This dyno is from a previous impeller wheel in the same blower. (The new impeller design should make a little more power, but I haven't dyno'd it.) I'm curious if a change of intake only, (not swapping my cam) would shift the powerband up more. Even if it costs me some torque down low. See how the power stops climbing at 6000rpms and starts to fall off? Is this a characteristic of Intake manifold or Camshaft?

A friend of mine swapped his stock intake for a holley hi ram. He went from 750 to 830 and lost 0 torque. I think he gained a few actually. 416 p1sc, e85. I'm thinking there is another 100whp to gain just with an intake swap.

What do you guys think? Anyone have any before and after charts of intake comparisons?

Given your extra displacement and heads, I'd be surprised if that wasn't the intake manifold holding you back, especially at higher rpm.

I'm with Larry. With your cubes and heads I would say the intake is a little under sized and you may notice a nice gain switching it up. I'll be following, as always, and good luck.

Since I wanted to push more boost than I thought the stock LS3 manifold could take, I first purchased a Fast LSXr but didn't install it as BTR was touting the new cast Equalizer which I figured I'd try. This chart is from the start of a dyno tune several years ago but the session was stopped well short due to finding (actually, the dyno found) a nail in one of my rear tires. One huge difference for me is how hot the Equalizer gets, and it does heat soak my injectors if I shutdown, wait 10-45 minutes. I'm working on my ITT tables that many tuners zero out (that's a no-no). Time to finish a real dyno tune to see what the setup will make.

I appreciate the feedback people. Dreksnot, no offense, but I can't really draw a conclusion from the chart, based on all the variables. I'm sure things would look very different had you finished tuning. Besides, our setups are drastically different as far as power curves go.

Does the BTR move the TB position? it's half the price of the LOD...

Goals

Sorry for the lack of explanation earlier. The BTR Equalizer is supposed to provide more power (torque) high end, like over 6,000rpm, which is where they claim it's better (than others). It is not supposed to lose much low end but I went cathedral ports in my heads to help that cause. My plot was to show that it appears their claims might be true as you can see the power plateau and not really dump like my LS3 setup. Yes, it was a different setup but I'm banking that what BTR said is mostly true.

Yes, the TB is slightly more forward (toward the front of the car) and has a slightly up angle (maybe 15-20deg).

The stock LS3 manifold is really good on stock cube NA stuff. It works well on boosted stuff up to maybe 750hp.
Beyond that, youre giving up a fair amount against the Holley or similar.

Just do an elbow on a Victor and run a 105mm tb. Way cheaper than the LOD or Holley.

Do you think the blower is big enough to feed the 427 at higher RPM ?
I'm not familiar with your blower setup.

I went with bigger turbo's and the BTR to change the powerband on mind,which it did and I love it.But still can't put big power down on the street till 90+mph on 20" Drag radials, It's better with the 17". Before I peaked around the same as you at 5500-5600RPM, now it pulls hard till 7000rpm(1100RWHP so far with a 6L90) which is perfect for me and still does 900+ rwtq between 4500-5500RPM.
But if I want more,then I'll have to go with bigger turbo's again.

Have you looked into this?
https://frankensteined.net/shop/low-...take-manifold/
Rpm makes great power with them.

https://youtu.be/YgftEd96Alc
Different motor but gives you a comparison between intakes and dyno numbers.

It has made 1280 on a 376, which i realize is not the same motor, but i dont think its maxed out. I can still spin it several thousand rpms faster (have the larger lower and smaller upper pulleys here). Since street traction seems to be lost anyhow, i may do just that. I’d still be willing to make it more efficient with a better intake tho.

No price listed, but i think they just raised pricing anyway. If you have to ask, you probably cant afford it…

Will that require cutting the hood?