427 LS2 with the LS7 top end.
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From 2500-4500 you have one "TQ peak" and then at 4500-5000 it pops up to the "real TQ peak".
The real TQ peak is pretty good. 519, might as well say 520rwtq. Can do better out of 427 cubic inches but not much.
You mentioned your compression was rather "conservative" at 10.8:1.
The "dual TQ peak" is due to large runner cross section. Its because the airspeed is not high enough for the cross section. Is likely that if the cross section of everything was a little smaller, head intake together flowed 340CFM, heads not opened, etc that from 2500-4500 wouldve been useful tq increase.
DId you say that the intake mani and heads bolted together flowed the 386CFM?
Don't remember if that was you. It does appear they widened the runners in the manifold and removed any protrusions into the air flow path.
From the looks of things, you have a good airflow situation with moderate cam, guessing in the lower 230's.
Not 250 or even 240, but lower 230's is my guess on the duration.
Some of us where expecting at least 625rwhp, to match that or nearly match that of the LGM, and about 535rwtq.
If the problem is that you guys just didn't spend enough time in getting the tune dead ***** on, then the power is there, fixing that so the TQ peak is 535rwtq instead of 520rwtq means power will be on the positive side of 600rwhp.
The real TQ peak is pretty good. 519, might as well say 520rwtq. Can do better out of 427 cubic inches but not much.
You mentioned your compression was rather "conservative" at 10.8:1.
The "dual TQ peak" is due to large runner cross section. Its because the airspeed is not high enough for the cross section. Is likely that if the cross section of everything was a little smaller, head intake together flowed 340CFM, heads not opened, etc that from 2500-4500 wouldve been useful tq increase.
DId you say that the intake mani and heads bolted together flowed the 386CFM?
Don't remember if that was you. It does appear they widened the runners in the manifold and removed any protrusions into the air flow path.
From the looks of things, you have a good airflow situation with moderate cam, guessing in the lower 230's.
Not 250 or even 240, but lower 230's is my guess on the duration.
Some of us where expecting at least 625rwhp, to match that or nearly match that of the LGM, and about 535rwtq.
If the problem is that you guys just didn't spend enough time in getting the tune dead ***** on, then the power is there, fixing that so the TQ peak is 535rwtq instead of 520rwtq means power will be on the positive side of 600rwhp.
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From: New Braunfels ,Tx
Originally Posted by Big-DEN
From 2500-4500 you have one "TQ peak" and then at 4500-5000 it pops up to the "real TQ peak".
The real TQ peak is pretty good. 519, might as well say 520rwtq. Can do better out of 427 cubic inches but not much.
You mentioned your compression was rather "conservative" at 10.8:1.
The "dual TQ peak" is due to large runner cross section. Its because the airspeed is not high enough for the cross section. Is likely that if the cross section of everything was a little smaller, head intake together flowed 340CFM, heads not opened, etc that from 2500-4500 wouldve been useful tq increase.
DId you say that the intake mani and heads bolted together flowed the 386CFM?
Don't remember if that was you. It does appear they widened the runners in the manifold and removed any protrusions into the air flow path.
From the looks of things, you have a good airflow situation with moderate cam, guessing in the lower 230's.
Not 250 or even 240, but lower 230's is my guess on the duration.
Some of us where expecting at least 625rwhp, to match that or nearly match that of the LGM, and about 535rwtq.
If the problem is that you guys just didn't spend enough time in getting the tune dead ***** on, then the power is there, fixing that so the TQ peak is 535rwtq instead of 520rwtq means power will be on the positive side of 600rwhp.
The real TQ peak is pretty good. 519, might as well say 520rwtq. Can do better out of 427 cubic inches but not much.
You mentioned your compression was rather "conservative" at 10.8:1.
The "dual TQ peak" is due to large runner cross section. Its because the airspeed is not high enough for the cross section. Is likely that if the cross section of everything was a little smaller, head intake together flowed 340CFM, heads not opened, etc that from 2500-4500 wouldve been useful tq increase.
DId you say that the intake mani and heads bolted together flowed the 386CFM?
Don't remember if that was you. It does appear they widened the runners in the manifold and removed any protrusions into the air flow path.
From the looks of things, you have a good airflow situation with moderate cam, guessing in the lower 230's.
Not 250 or even 240, but lower 230's is my guess on the duration.
Some of us where expecting at least 625rwhp, to match that or nearly match that of the LGM, and about 535rwtq.
If the problem is that you guys just didn't spend enough time in getting the tune dead ***** on, then the power is there, fixing that so the TQ peak is 535rwtq instead of 520rwtq means power will be on the positive side of 600rwhp.
I feel that the tune is doing fine. And the car drives everywhere. But your more than welcome to give us any tips on tuning. AFR is 13.1 across the board And Im in Texas 
Originally Posted by JMBLOWNWS6
I have no intentions of beating anyone's numbers. I could have been a BS lair and slapped motorsport 109 milled the heads and added more timing and made more. But why? To prove on the internet I can make 600+ RWHP? Like Tony Mamo sig says Tony "Morpheus" Mamo invites you to take the Blue Pill...welcome to the "real world" I feel that the tune is doing fine. And the car drives everywhere. But your more than welcome to give us any tips on tuning. AFR is 13.1 across the board And Im in Texas
I feel that the tune is doing fine. And the car drives everywhere. But your more than welcome to give us any tips on tuning. AFR is 13.1 across the board And Im in Texas TECH Apprentice
Joined: Oct 2004
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JMBLOWNWS6.
I was simply giving my own technical evaluation. Thats it.
How can someone mix technical talk with calling someone out, I'm still trying to figure that one out.
Do what you want.
SOmebody else is going to say the graphs look terribly close to a Fast90/408 combination.
I was simply giving my own technical evaluation. Thats it.
How can someone mix technical talk with calling someone out, I'm still trying to figure that one out.
Do what you want.
SOmebody else is going to say the graphs look terribly close to a Fast90/408 combination.
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From: New Braunfels ,Tx
Originally Posted by Big-DEN
JMBLOWNWS6.
I was simply giving my own technical evaluation. Thats it.
How can someone mix technical talk with calling someone out, I'm still trying to figure that one out.
Do what you want.
SOmebody else is going to say the graphs look terribly close to a Fast90/408 combination.
I was simply giving my own technical evaluation. Thats it.
How can someone mix technical talk with calling someone out, I'm still trying to figure that one out.
Do what you want.
SOmebody else is going to say the graphs look terribly close to a Fast90/408 combination.
(Just a joke) I would like to see a 408 making 570+ RWHP. Let me know. Because this isnt my first stroker nor will it be my last. BTW I do have another Z06 that is making 535 rwhp and its a 402 from TSP. I feel the time and effort put into this car is very pleaseing but I understand this is the net and someone is always a critic. But its understandable. I am also glad to say that the owner of this engine is very happy with the numbers. And thats all the really matters. But I wanted to share on here since this is some of the lastest and greatest GM stock parts modified GM has to offer. Now on a side note do you have anything like this? Not calling you out but it would be nice to compare. Thanks for your time. Maybe I came off wrong. But Im like that so dont take it personal. I will say this, We asked LME for a 427 and let them handle all the specs and compression and they delivered. All I really have to say about it. 
Joe M
Last edited by JMBLOWNWS6; Oct 25, 2006 at 05:40 PM.
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Joe,
Glad you didn't turn this personal, cause for me these forums are purely tech. sometimes talking tech can come across cold, but that is not the intention.
There was a few 540-560rwhp fast90/402's. Is all I was talking about. Theyre not going to the limit, but many do use larger cams in the 240-250ish range.
I'd love to have yours for sure. Never trying knock it, just some of us when we saw the flow of the heads and the short block design on the LS7 thought 600rwhp N/A world would be more common.
On your graph, wasn't knocking it, making a technical evaluation.
The one thing about most LSx graphs with LS1 thru the fast90, is no double hump TQ peaks. Normally the TQ peak looks like a hill and you might stay at or near the peak for 2000RPM.
With yours was a definiative double peak, and I saw that on the ford world in a situation where you had alot of flow IE: Holley intake ported and heads and intake flow high, say even over 300CFM as a unit. However the runner length on the holley optimize VE at a lower rpm point. So we get this double hump tq peak. Just saying I seen it before, how to fix it, now thats another problem. to say it differnetly, the runner length and cross section aren't "syncing" when it comes to the resonance tuning.
We'll see, i know theres alot in yours thats for sure. the heads wont be a sticking point till like 800-850HP engine.
Oh
Glad you didn't turn this personal, cause for me these forums are purely tech. sometimes talking tech can come across cold, but that is not the intention.
There was a few 540-560rwhp fast90/402's. Is all I was talking about. Theyre not going to the limit, but many do use larger cams in the 240-250ish range.
I'd love to have yours for sure. Never trying knock it, just some of us when we saw the flow of the heads and the short block design on the LS7 thought 600rwhp N/A world would be more common.
On your graph, wasn't knocking it, making a technical evaluation.
The one thing about most LSx graphs with LS1 thru the fast90, is no double hump TQ peaks. Normally the TQ peak looks like a hill and you might stay at or near the peak for 2000RPM.
With yours was a definiative double peak, and I saw that on the ford world in a situation where you had alot of flow IE: Holley intake ported and heads and intake flow high, say even over 300CFM as a unit. However the runner length on the holley optimize VE at a lower rpm point. So we get this double hump tq peak. Just saying I seen it before, how to fix it, now thats another problem. to say it differnetly, the runner length and cross section aren't "syncing" when it comes to the resonance tuning.
We'll see, i know theres alot in yours thats for sure. the heads wont be a sticking point till like 800-850HP engine.
Oh
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From: New Braunfels ,Tx
Originally Posted by KAOS
i bet with a carb style intake you would hit that 600 mark. it seems to help out FI guys a lot and would bet it would dominate on this setup. looks awesome. great numbers and good luck
But all in all the OWNER of the car is happy. And that is the bottom line 
Oh yea. SAE numbers are 568 rwhp and 508 TQ Last edited by JMBLOWNWS6; Oct 26, 2006 at 10:50 AM.
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From: Mpls., MN
Originally Posted by KAOS
i bet with a carb style intake you would hit that 600 mark. it seems to help out FI guys a lot and would bet it would dominate on this setup. looks awesome. great numbers and good luck
HiTech
Originally Posted by HTMtrSprt
I would agree.... the LSx style intakes will never allow the engine to make more than about 650-675 crankshaft HP so the cam in this motor is probably a litttle big on the intake duration and the runners are definitely too large in cross section for this HP level. The bummer is that there are now many different heads available out there that just aren't going to do anything for you unless you change the manifold to a Victor, Billet Bank, or some other sheet metal design and are willing to rev it up past 7K. The reality is that the LSx series engine has about maxed the tq/cubic inch ratio with known technology and the only way now to make more power is make it bigger or wind it higher.
HiTech
HiTech
The LS7 intake, while perhaps the best 'production' or plastic piece to date, still completely butchers the true potential of the heads. If someone came out with a sheet metal intake that was more of a production piece, they'd be rich.
piece to date, still completely butchers the true potential of the heads. If someone came out with a sheet metal intake that was more of a production piece, they'd be rich. IMO the reason most of the FI guys go with the carb style is durability. They are pushing boost pressures way past what a poly intake can take. FI is a whole different world.
Originally Posted by Greg Fell
The LS7 intake, while perhaps the best 'production' or plastic piece to date, still completely butchers the true potential of the heads. If someone came out with a sheet metal intake that was more of a production piece, they'd be rich.
piece to date, still completely butchers the true potential of the heads. If someone came out with a sheet metal intake that was more of a production piece, they'd be rich.
Nice numbers.... With a little more compression the torque would be better and maybe even a little more HP.
Why are you spinning it to less than 7K RPM? I plan to spin mine to 7200-7400rpm. Didn't look like the HP was falling off...
What rings are in this engine? I'm thinking about running some Total Seal file fit rings.
I have 11.25:1 compression and plan to run 91 octane. Healthy size cam. LS7 block/crank, forged rods/pistons, ported LS7 intake/LS7heads.
Why are you spinning it to less than 7K RPM? I plan to spin mine to 7200-7400rpm. Didn't look like the HP was falling off...
What rings are in this engine? I'm thinking about running some Total Seal file fit rings.
I have 11.25:1 compression and plan to run 91 octane. Healthy size cam. LS7 block/crank, forged rods/pistons, ported LS7 intake/LS7heads.