Giant LS3 Intake Manifold Dyno Shootout!
03-07-2018, 07:47 AM
#41
10 Second Club
Torque always noses over before hp peak, that's how it works. Torque will be falling but if rpm is climbing and horsepower doesn't take a drastic dive it'll still be faster shifting higher. Only the tow truck intakes give up hard after 6600. Several of the intakes in this test appear like they would excel with a 7500+ shift point even with the baby cam and stock heads, but we can't tell how far because the test was ended early, that's the point people are trying to make. A set of valvesprings and another 500+ rpm would have offered much more valuable data.
No, the ls3 intake isn’t some amazing high performance monster
However for Cam only ls3’s with a Cam that’s specd within the same operating range as Stock it’s a very good fit for that. It is great for cookie cutter builds. It is not great for high HP builds.
03-07-2018, 08:06 AM
#43
03-07-2018, 08:13 AM
#44
10 Second Club
Yet almost every graph there aside from those "bigger" intakes they're peaking a little before 6500 in that test.
And torque has already nose dived long before.
So lets see these graphs of yours and your intake excelling all the way to 7500 ? Maybe if you could prove it to people more would try ?
What cam etc ?
And torque has already nose dived long before.
So lets see these graphs of yours and your intake excelling all the way to 7500 ? Maybe if you could prove it to people more would try ?
What cam etc ?
This Cam was pretty mild. It has a bigger one now but I haven’t had a chance to re dyno
03-07-2018, 10:21 AM
#47
I have potential for huge gains with better high rpm tuning. This is stock ls3 heads and intake, hooker exhaust manifolds, and a wide center cam with 226* intake duration on an LS2 stroker.
Even if I was able to just hang onto 470whp to 7200 rpm my car would pick up substantially. If peak was shifted higher, and more power was made...it'd be a different world. Potential 50hp+ gain at 7000 rpm.
Even if I was able to just hang onto 470whp to 7200 rpm my car would pick up substantially. If peak was shifted higher, and more power was made...it'd be a different world. Potential 50hp+ gain at 7000 rpm.
03-07-2018, 11:16 AM
#49
Similar to mine. 226/242 on 117 ICL 113.5. I don't think I should be out of cam above 6000 rpm. In fact...being such a wide center I expected it to carry power pretty well.
Stock LS3 heads can support 550whp pretty easily too..I don't think they're a heavy restriction.
Stock LS3 heads can support 550whp pretty easily too..I don't think they're a heavy restriction.
03-07-2018, 11:54 AM
#50
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I have potential for huge gains with better high rpm tuning. This is stock ls3 heads and intake, hooker exhaust manifolds, and a wide center cam with 226* intake duration on an LS2 stroker.
Even if I was able to just hang onto 470whp to 7200 rpm my car would pick up substantially. If peak was shifted higher, and more power was made...it'd be a different world. Potential 50hp+ gain at 7000 rpm.
Even if I was able to just hang onto 470whp to 7200 rpm my car would pick up substantially. If peak was shifted higher, and more power was made...it'd be a different world. Potential 50hp+ gain at 7000 rpm.
Assuming a F-Bomb T56, first gear is 2.66, second gear is 1.78, I'll pick a rear gear of 4.11, but it really doesn't matter what rear gear ratio is for this exercise.
At 6800 RPM, you're at 335 lbs of tq. Do the gear multiplication to get to the tires, and you're at 3662 lbs rear tire tq. So, you up-shift from 1-2, and you land at 4550 RPM and 450 lbs of torque, which gear multiplies out to 3292 pounds rear wheel torque.
So, you're WAY past your power peak (6000) RPM and you STILL lost 360 lbs torque on the upshift, even though you landed RIGHT ON PEAK ENGINE TORQUE. SO it's still to your advantage to stay in the lower gear at 6800 RPM.
Projecting your torque curve out to 7200 RPM and 300 lbs of torque, you're finally to the point at which it's no longer a loss to upshift. You'll land at 4800 RPM, still right in the meat of your torque curve, and ride that curve down again.
The 2-3 shift isn't so big a split, so you shift right around 6800, which is 2450 in both second at 6800 and third at 5100.
3-4 shift is pretty much the same as 2-3, where you're right at 1850 in both gears.
How much more is the above going to be true for an intake that peaks at or near 7K and then carries? That power past peak is more important than it's being credited. At least in the 1/4 mile. Again, autos do a better job keeping the engine right at peak power, but to say an engine is done when it hits peak is leaving quite a lot on the table for performance.
03-07-2018, 12:23 PM
#51
You're pretty spot on there Darth.
I have 3.73's and F-body ratio T56 Magnum in the car now and shift usually just after 6500, go through the traps at 6500.
When I had 4.10's and the GTO MN12 ratios I'd regularly shift at 7000 and in the lights it's tongue was hanging out at 7200.
Little shaky, but you can see the tach on both of these.
Old (excuse the cluster I was in process of installing Speedhut gauges) -
New -
I have 3.73's and F-body ratio T56 Magnum in the car now and shift usually just after 6500, go through the traps at 6500.
When I had 4.10's and the GTO MN12 ratios I'd regularly shift at 7000 and in the lights it's tongue was hanging out at 7200.
Little shaky, but you can see the tach on both of these.
Old (excuse the cluster I was in process of installing Speedhut gauges) -
New -
03-07-2018, 12:28 PM
#52
9 Second Club
Of course if power can hang on for another few hundred rpm then that's fine but on some of the graphs it's obvious it is taking a nose dive....and equally obvious there's still some life left in it
We'd all love to see thousands of dyno tests and comparisons with different builds...but sadly none of the intake companies even offer them nevermind anyone else
The intake test is still valid and highlights where some shine..and where some fail which can still be applied across the board
Of course I'd prefer to see all the tests with boost too....but fat chance of that either.
03-07-2018, 12:30 PM
#53
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^ thats actually a really great explanation Darth.
I think the basis of this test covers a majority of the customers though. The part where it fails is in the fact that they are trying the intakes that are made for higher RPM gains in the same window as those that are not and trying to make it an apples to apples comparison, which it isnt. its a good baseline study of that setup and the selected intakes, but not the intakes as a whole.
I make my statement about not switching based on the fact that I dont need the higher peak power so the trade off is a big chunk of change for a setup the car isnt planned to grow into. I dont gain anything on my car as its not a race car ( i know who puts a stroker in a street car) so its money for an appearance mod which im all for, but in the end I cant justify it currently.
I think the basis of this test covers a majority of the customers though. The part where it fails is in the fact that they are trying the intakes that are made for higher RPM gains in the same window as those that are not and trying to make it an apples to apples comparison, which it isnt. its a good baseline study of that setup and the selected intakes, but not the intakes as a whole.
I make my statement about not switching based on the fact that I dont need the higher peak power so the trade off is a big chunk of change for a setup the car isnt planned to grow into. I dont gain anything on my car as its not a race car ( i know who puts a stroker in a street car) so its money for an appearance mod which im all for, but in the end I cant justify it currently.
03-07-2018, 12:32 PM
#54
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Nobody is saying it's done....but to hang on beyond where it really wants just for sake of hanging on also serves no purpose.
Of course if power can hang on for another few hundred rpm then that's fine but on some of the graphs it's obvious it is taking a nose dive....and equally obvious there's still some life left in it
We'd all love to see thousands of dyno tests and comparisons with different builds...but sadly none of the intake companies even offer them nevermind anyone else
The intake test is still valid and highlights where some shine..and where some fail which can still be applied across the board
Of course I'd prefer to see all the tests with boost too....but fat chance of that either.
Of course if power can hang on for another few hundred rpm then that's fine but on some of the graphs it's obvious it is taking a nose dive....and equally obvious there's still some life left in it
We'd all love to see thousands of dyno tests and comparisons with different builds...but sadly none of the intake companies even offer them nevermind anyone else
The intake test is still valid and highlights where some shine..and where some fail which can still be applied across the board
Of course I'd prefer to see all the tests with boost too....but fat chance of that either.
I'm still stumped as to why the ITB did not do better, unless the 50mm throttles are smaller than the runner cross section and served as choke points or the runner lengths were just wrong for the motor.
03-07-2018, 12:43 PM
#55
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^ thats actually a really great explanation Darth.
I think the basis of this test covers a majority of the customers though. The part where it fails is in the fact that they are trying the intakes that are made for higher RPM gains in the same window as those that are not and trying to make it an apples to apples comparison, which it isnt. its a good baseline study of that setup and the selected intakes, but not the intakes as a whole.
I make my statement about not switching based on the fact that I dont need the higher peak power so the trade off is a big chunk of change for a setup the car isnt planned to grow into. I dont gain anything on my car as its not a race car ( i know who puts a stroker in a street car) so its money for an appearance mod which im all for, but in the end I cant justify it currently.
I think the basis of this test covers a majority of the customers though. The part where it fails is in the fact that they are trying the intakes that are made for higher RPM gains in the same window as those that are not and trying to make it an apples to apples comparison, which it isnt. its a good baseline study of that setup and the selected intakes, but not the intakes as a whole.
I make my statement about not switching based on the fact that I dont need the higher peak power so the trade off is a big chunk of change for a setup the car isnt planned to grow into. I dont gain anything on my car as its not a race car ( i know who puts a stroker in a street car) so its money for an appearance mod which im all for, but in the end I cant justify it currently.
I get hung up on the phrase "power under the curve". most people say that but actually mean "torque under the curve". If you truly want to maximize "power under the curve" you'' put your peak power right int he middle of your gear splits.
Anyway, good stuff, and fun dialog.
03-07-2018, 12:44 PM
#56
9 Second Club
ITB's could be the angle of the runner, blade position, runner length or maybe a lack of physical plenum ? Open may not always be best.
But a vertical runner that then needs to turn into the port...is bound to have issues compared to the other styles that get a straight shot in
An ITB setup more like Jenvey's that crossover each other would be better to see....but the Edelbrock crossram is sort of heading that direction but seemed rather lacklustre.
But then....lots of things would be better to see.
But a vertical runner that then needs to turn into the port...is bound to have issues compared to the other styles that get a straight shot in
An ITB setup more like Jenvey's that crossover each other would be better to see....but the Edelbrock crossram is sort of heading that direction but seemed rather lacklustre.
But then....lots of things would be better to see.
03-07-2018, 01:10 PM
#57
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Thanks, man. And I agree with what you're saying here. Your intended RPM range is best suited for LS3 intake, and that's fine. But hammer would be an idiot NOT to rev out his.
I get hung up on the phrase "power under the curve". most people say that but actually mean "torque under the curve". If you truly want to maximize "power under the curve" you'' put your peak power right int he middle of your gear splits.
Anyway, good stuff, and fun dialog.
I get hung up on the phrase "power under the curve". most people say that but actually mean "torque under the curve". If you truly want to maximize "power under the curve" you'' put your peak power right int he middle of your gear splits.
Anyway, good stuff, and fun dialog.
though im was shocked the ITB didnt show better, was also shocked the low profile sheet metal did well it actually seemed like the more viable option in scenario, Ive got a heafty cam and I know with my intake im leaving some on the table, but is it enough to bother with and at that point does it matter.
03-07-2018, 01:12 PM
#58
I think the ITB's were just too short. This LS7 picked up tons of power everywhere with 50mm ITB's.
That said, I do think 50mm is a little small. The throat of the ITB is smaller than the flange on the intake, and nearly identical to the min CSA of the stock head.
http://www.superchevy.com/how-to/eng...t-intake-test/
FYI - I found the stock ls3 intake has ~10" runner length. I don't know the CSA of the stock intake runners.
Anyone know the length of the intake port itself from the back of the valve to the intake flange? 3"?
That said, I do think 50mm is a little small. The throat of the ITB is smaller than the flange on the intake, and nearly identical to the min CSA of the stock head.
http://www.superchevy.com/how-to/eng...t-intake-test/
FYI - I found the stock ls3 intake has ~10" runner length. I don't know the CSA of the stock intake runners.
Anyone know the length of the intake port itself from the back of the valve to the intake flange? 3"?
03-07-2018, 01:15 PM
#59
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Great explanation darth. Most don't get that and i suck at splainin it for them.
That thong should make way more power
Have you dyno'd it?
Which is exactly why you spin it harder. You're not gonna get there in the stock rpm range with a 6.2
I have potential for huge gains with better high rpm tuning. This is stock ls3 heads and intake, hooker exhaust manifolds, and a wide center cam with 226* intake duration on an LS2 stroker.
Even if I was able to just hang onto 470whp to 7200 rpm my car would pick up substantially. If peak was shifted higher, and more power was made...it'd be a different world. Potential 50hp+ gain at 7000 rpm.
Even if I was able to just hang onto 470whp to 7200 rpm my car would pick up substantially. If peak was shifted higher, and more power was made...it'd be a different world. Potential 50hp+ gain at 7000 rpm.
Which is exactly why you spin it harder. You're not gonna get there in the stock rpm range with a 6.2
03-07-2018, 01:22 PM
#60
10 Second Club
Shifting past peak makes perfect sense if you’re using more average Hp than if you shift at peak. That why you need to run them out on the dyno. Limiting the better intakes to 7000 is severely Restricting their potential