Intake Manifold Flow Tests: LS1, LS6, TBSS, BBK, Dorman LS2, 102 Fast LSXRT & more
02-27-2017, 08:40 PM
#21
thank you for taking the time to get this tested. im very impressed with this. it stayed ahead of the tbss intake until about .600" of lift and even not that far behind at .650" lift. like you stated before, that intake is widely regarded as being the best performing factory intake and dyno proven to make more power over the ls6. i am really curious as to how much more it can
i think that right there would be enough to say that its an improvement over the ls2 since, and please correct if im mistaken, the ls6 performs better then ls2. i am just deducing different things that i have gathered and stored in my collective memory......
i think that right there would be enough to say that its an improvement over the ls2 since, and please correct if im mistaken, the ls6 performs better then ls2. i am just deducing different things that i have gathered and stored in my collective memory......
02-27-2017, 09:37 PM
#22
The LS2 intake performance is less than expected. The runners will leak air internally. This is due to the manufacturing process GM used of two pieces and sonic welding. The LS6 intake has been shown to outperform the LS2 in various dyno tests, despite the LS2 having a 90mm snout for a 90mm TB vs LS6 78mm. Dorman didn't directly copy the GM LS2, its obvious they made changes. The LS1 Fuel rail fits the Dorman LS2 for examplet.The TBSS intake stomps the LS2 in flow and Hp, the Dorman LS2 flows better than the TBSS clearly some changes were made.
We need a dyno test to really see what the Dorman LS2 will deliver. Flow numbers help but the acid test is the performance.
My 99 TA is getting valve springs tomorrow but will have to have a new clutch & fuel pump before being top notch condition to do dyno testing. So it might be 2 months before I can get any dyno numbers.
Last edited by 99 Black Bird T/A; 02-27-2017 at 09:55 PM.
02-28-2017, 08:33 AM
#24
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I will try to share what I learned.
The LS2 intake performance is less than expected. The runners will leak air internally. This is due to the manufacturing process GM used of two pieces and sonic welding. The LS6 intake has been shown to outperform the LS2 in various dyno tests, despite the LS2 having a 90mm snout for a 90mm TB vs LS6 78mm. Dorman didn't directly copy the GM LS2, its obvious they made changes. The LS1 Fuel rail fits the Dorman LS2 for examplet.The TBSS intake stomps the LS2 in flow and Hp, the Dorman LS2 flows better than the TBSS clearly some changes were made.
We need a dyno test to really see what the Dorman LS2 will deliver. Flow numbers help but the acid test is the performance.
My 99 TA is getting valve springs tomorrow but will have to have a new clutch & fuel pump before being top notch condition to do dyno testing. So it might be 2 months before I can get any dyno numbers.
The LS2 intake performance is less than expected. The runners will leak air internally. This is due to the manufacturing process GM used of two pieces and sonic welding. The LS6 intake has been shown to outperform the LS2 in various dyno tests, despite the LS2 having a 90mm snout for a 90mm TB vs LS6 78mm. Dorman didn't directly copy the GM LS2, its obvious they made changes. The LS1 Fuel rail fits the Dorman LS2 for examplet.The TBSS intake stomps the LS2 in flow and Hp, the Dorman LS2 flows better than the TBSS clearly some changes were made.
We need a dyno test to really see what the Dorman LS2 will deliver. Flow numbers help but the acid test is the performance.
My 99 TA is getting valve springs tomorrow but will have to have a new clutch & fuel pump before being top notch condition to do dyno testing. So it might be 2 months before I can get any dyno numbers.
02-28-2017, 08:35 AM
#25
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Wow. Nice work..
I'd love to see what a stock ls6 intake does, and the tpis ls6 for that matter.
Great headflow btw.
A bit dissapointed the truck intake is almost as good as an ls6 style 90mm intake is. Or maybe really a bit impressed. Didnt know the tbss intake was that good.
I'd love to see what a stock ls6 intake does, and the tpis ls6 for that matter.
Great headflow btw.
A bit dissapointed the truck intake is almost as good as an ls6 style 90mm intake is. Or maybe really a bit impressed. Didnt know the tbss intake was that good.
02-28-2017, 11:26 AM
#26
I will try to share what I learned.
The LS2 intake performance is less than expected. The runners will leak air internally. This is due to the manufacturing process GM used of two pieces and sonic welding. The LS6 intake has been shown to outperform the LS2 in various dyno tests, despite the LS2 having a 90mm snout for a 90mm TB vs LS6 78mm. Dorman didn't directly copy the GM LS2, its obvious they made changes. The LS1 Fuel rail fits the Dorman LS2 for examplet.The TBSS intake stomps the LS2 in flow and Hp, the Dorman LS2 flows better than the TBSS clearly some changes were made.
We need a dyno test to really see what the Dorman LS2 will deliver. Flow numbers help but the acid test is the performance.
My 99 TA is getting valve springs tomorrow but will have to have a new clutch & fuel pump before being top notch condition to do dyno testing. So it might be 2 months before I can get any dyno numbers.
The LS2 intake performance is less than expected. The runners will leak air internally. This is due to the manufacturing process GM used of two pieces and sonic welding. The LS6 intake has been shown to outperform the LS2 in various dyno tests, despite the LS2 having a 90mm snout for a 90mm TB vs LS6 78mm. Dorman didn't directly copy the GM LS2, its obvious they made changes. The LS1 Fuel rail fits the Dorman LS2 for examplet.The TBSS intake stomps the LS2 in flow and Hp, the Dorman LS2 flows better than the TBSS clearly some changes were made.
We need a dyno test to really see what the Dorman LS2 will deliver. Flow numbers help but the acid test is the performance.
My 99 TA is getting valve springs tomorrow but will have to have a new clutch & fuel pump before being top notch condition to do dyno testing. So it might be 2 months before I can get any dyno numbers.
02-28-2017, 03:27 PM
#30
Yes, I would love to test other intakes! Shoot me a PM please an I will see about part w for another 4 to 6 intakes.
Btw my LG G4 phone just did the boot loop of death so im on a tablet and its hard to type...sorry for the typos
Btw my LG G4 phone just did the boot loop of death so im on a tablet and its hard to type...sorry for the typos
Last edited by 99 Black Bird T/A; 02-28-2017 at 09:33 PM.
02-28-2017, 09:00 PM
#32
We can do stage 2 of this testing I checked with the shop. I will have 2 more tests of my own. If we can get 2 to 6 intakes to test that world be great. I would need the send to cover shipping and i will cover the cost of flow testing. It may take a few weeks so please be sure you're ok with that.
I will get my Dorman LS2 Peak ported for one of the tests.
Darth, thanks it's been a lot of fun testing and seeing the results. I think the DormanLS2 will make a nice subtle upgrade over the stock LS2. Dyno would be the ideal way to confirm.
1970RS. I would be happy to get antests.or other intake tested if someone can provide one. I would ship it back as soon as the test was done.
Wanna body, I would be delighted to arrange a test for the BBK if one is provided for me to test. Will ship back asap after testing.
5LTR ETR That soundx great! I want to text. Dorman LS6 very much. I have a ported LS1 TB to ensure it gets the same sort of test the 92mm intakes get.
Codyvette PM sent, I would love to test a TPiS LS6!
Taman86 PM sent i would love to test an LS6 and the adapter!
If i missed anyone please pm me and we will try to get the 2nd phase of testing lined up.
I will get my Dorman LS2 Peak ported for one of the tests.
Darth, thanks it's been a lot of fun testing and seeing the results. I think the DormanLS2 will make a nice subtle upgrade over the stock LS2. Dyno would be the ideal way to confirm.
1970RS. I would be happy to get antests.or other intake tested if someone can provide one. I would ship it back as soon as the test was done.
Wanna body, I would be delighted to arrange a test for the BBK if one is provided for me to test. Will ship back asap after testing.
5LTR ETR That soundx great! I want to text. Dorman LS6 very much. I have a ported LS1 TB to ensure it gets the same sort of test the 92mm intakes get.
Codyvette PM sent, I would love to test a TPiS LS6!
Taman86 PM sent i would love to test an LS6 and the adapter!
If i missed anyone please pm me and we will try to get the 2nd phase of testing lined up.
Last edited by 99 Black Bird T/A; 02-28-2017 at 09:14 PM.
02-28-2017, 09:17 PM
#33
5LTR all intakes were tested bolted to the cylinder head. The WARR 92mm TB was mounted on the intakes for the testing except the LS1 intake. I plan to retest the ls1 intake with a ported tb. I think the tb helps the runner a little bit. The tb blade is zip tied open. The head is flowed then the various intakes & tb bolted to the cylinder head and tested. At the end the cylinder head is tested again to make sure the test has stay consistant.
Dyno testing all of this would be ideal but is beyond my budget for this many intakes.
All ls intakes reduce the flow of the intake port the question is by how much. Intakes are basically fancy restrictor plates
The only exception might be ITB stack intake like a kinsler or panther efi itb stack.
Dyno testing all of this would be ideal but is beyond my budget for this many intakes.
All ls intakes reduce the flow of the intake port the question is by how much. Intakes are basically fancy restrictor plates
The only exception might be ITB stack intake like a kinsler or panther efi itb stack.
Last edited by 99 Black Bird T/A; 02-28-2017 at 09:31 PM.
03-01-2017, 03:48 AM
#34
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Im into audi's as well. And you just dont see this kind of dedication or skills on euro car forums..
They make diy's for plug changes and brake changes etc. Nothing hard or interesting really.
Good thing i have an ls1 gbody bu'
Thanks again for the great work
They make diy's for plug changes and brake changes etc. Nothing hard or interesting really.
Good thing i have an ls1 gbody bu'
Thanks again for the great work
03-01-2017, 08:01 AM
#35
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5LTR all intakes were tested bolted to the cylinder head. The WARR 92mm TB was mounted on the intakes for the testing except the LS1 intake. I plan to retest the ls1 intake with a ported tb. I think the tb helps the runner a little bit. The tb blade is zip tied open. The head is flowed then the various intakes & tb bolted to the cylinder head and tested. At the end the cylinder head is tested again to make sure the test has stay consistant.
Dyno testing all of this would be ideal but is beyond my budget for this many intakes.
All ls intakes reduce the flow of the intake port the question is by how much. Intakes are basically fancy restrictor plates
The only exception might be ITB stack intake like a kinsler or panther efi itb stack.
Dyno testing all of this would be ideal but is beyond my budget for this many intakes.
All ls intakes reduce the flow of the intake port the question is by how much. Intakes are basically fancy restrictor plates
The only exception might be ITB stack intake like a kinsler or panther efi itb stack.
IIRC, every CFM frees up a potential 2 HP depending ont he rest of the combination being able to take advantage?
03-01-2017, 08:17 AM
#37
Totally get it. There was that hotrod magazine article a while back that compared all the cathedral intakes on an engine dyno. We know from that article how much better the TBSS did vs the stock LS1 intake. As far as I'm concerned, the intake that shows the least amount of drop vs open heads does the best.
IIRC, every CFM frees up a potential 2 HP depending ont he rest of the combination being able to take advantage?
IIRC, every CFM frees up a potential 2 HP depending ont he rest of the combination being able to take advantage?
So if you can avg 15cfm more across the flow chart, you'll typically pick up 25-30HP. Assuming, of course, you didn't increase CSA by some insane amount in the heads to get there. As far as manifolds go... I don't think they can be too big. The bigger they are, the better they can fill the cylinders. But runner length and design and overall volume determine where they are most efficient in helping the cylinder pick up additional flow.
03-01-2017, 08:24 AM
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That's about right.
So if you can avg 15cfm more across the flow chart, you'll typically pick up 25-30HP. Assuming, of course, you didn't increase CSA by some insane amount in the heads to get there. As far as manifolds go... I don't think they can be too big. The bigger they are, the better they can fill the cylinders. But runner length and design and overall volume determine where they are most efficient in helping the cylinder pick up additional flow.
So if you can avg 15cfm more across the flow chart, you'll typically pick up 25-30HP. Assuming, of course, you didn't increase CSA by some insane amount in the heads to get there. As far as manifolds go... I don't think they can be too big. The bigger they are, the better they can fill the cylinders. But runner length and design and overall volume determine where they are most efficient in helping the cylinder pick up additional flow.
Basically, the point I was making was that since he is measuring intake port flow through both the intake and the head, the flow numbers are meaningful and valuable.
And I agree, larger plenum is almost always preferable. That's where the ITB arrangement has the best potential - the earth's atmosphere is the plenum. Hard to get much bigger than that!
03-01-2017, 09:49 AM
#40
I think the most I've seen some builders quote is around 2.1 to 2.3 HP per CFM if everything in the combo is perfect. It's much easier to make less than that. But you can't make more. And I would assume that's race fuel, high RPM, and lots of compression, cam timing, and spark.
So an honest-to-god 320cfm head can make upwards of 700+HP at the crank. And 400cfm heads could do damn near 900HP. We don't see that too often. We see 380-400cfm rectangle port heads doing 700-750 a lot in streetable setups and 340cfm cathederal port heads doing 650-675...
So, I think that 1.75HP per cfm for the rectangle port and close to 2HP per CFM on the cathedral stuff is probably closer to what we'd want in a car we'd drive on the street in a well optimized combo. And part of that is head efficiency and the other part is just the plastic intakes aren't going to support 400cfm.
So the heads used here could support 610HP in a very well-optimized combo and probably somewhere between that and 530HP with a decent combo. And the FAST LSXRT would support 490HP at the lower end and closer to 560 at the very well-optimized combo.
Of course, flow through the manifold increases as the head flow increases. So the better the head, the better the power. A better manifold just helps optimize the combo.
So an honest-to-god 320cfm head can make upwards of 700+HP at the crank. And 400cfm heads could do damn near 900HP. We don't see that too often. We see 380-400cfm rectangle port heads doing 700-750 a lot in streetable setups and 340cfm cathederal port heads doing 650-675...
So, I think that 1.75HP per cfm for the rectangle port and close to 2HP per CFM on the cathedral stuff is probably closer to what we'd want in a car we'd drive on the street in a well optimized combo. And part of that is head efficiency and the other part is just the plastic intakes aren't going to support 400cfm.
So the heads used here could support 610HP in a very well-optimized combo and probably somewhere between that and 530HP with a decent combo. And the FAST LSXRT would support 490HP at the lower end and closer to 560 at the very well-optimized combo.
Of course, flow through the manifold increases as the head flow increases. So the better the head, the better the power. A better manifold just helps optimize the combo.