SStrokerAce, update on LT1 intake?
Registered User
Joined: Oct 2001
Posts: 282
From: IL
Originally posted by SStrokerAce
Moss,
The LT1 intake lacks in what is called intake pulse tuning in the RPM range we run them in. Intake pusle tuning is basically physics at work making fake boost at certain RPM and cramming more air/fuel into the cylinder therefore making more power. You can see up to 5-7psi extra so in essence it's like a blower. If you ever wonder why a 500cu in Pro Stock motor makes 1350hp on gas and carbs with no extra help it's because they make very good use of this "faux boost". In fact F1, MotoGP, NASCAR motors which all have very high Volumetric Efficiency use this intake pulse tuining to their advantage. For a definition of Vol Eff go here http://www.auto-ware.com/combust_bytes/eng_sci.htm
Here is some more stuff on VE http://www.epi-eng.com/ET-VolEff.htm
A quote from that is what we are tring to shoot for here:
"For contemporary naturally-aspirated, two-valve-per-cylinder, pushrod engine technology, a VE over 95% is excellent, and 100% is achievable, but quite difficult. Only the best of the best can exceed 110%, and that is by means of extremely specialized development of the complex system comprised of the intake passages, combustion chambers, exhaust passages and valve system components."
This is how a Nextel Cup motor with 358cubes and a flat tappet cam can make more TQ than most 383 LT1's. 540ft lbs and they are tring to build HP with those motors. On top of that they are restricted to certain intake sizes due to rules on the intake manifold castings they can use.
Bret
Moss,
The LT1 intake lacks in what is called intake pulse tuning in the RPM range we run them in. Intake pusle tuning is basically physics at work making fake boost at certain RPM and cramming more air/fuel into the cylinder therefore making more power. You can see up to 5-7psi extra so in essence it's like a blower. If you ever wonder why a 500cu in Pro Stock motor makes 1350hp on gas and carbs with no extra help it's because they make very good use of this "faux boost". In fact F1, MotoGP, NASCAR motors which all have very high Volumetric Efficiency use this intake pulse tuining to their advantage. For a definition of Vol Eff go here http://www.auto-ware.com/combust_bytes/eng_sci.htm
Here is some more stuff on VE http://www.epi-eng.com/ET-VolEff.htm
A quote from that is what we are tring to shoot for here:
"For contemporary naturally-aspirated, two-valve-per-cylinder, pushrod engine technology, a VE over 95% is excellent, and 100% is achievable, but quite difficult. Only the best of the best can exceed 110%, and that is by means of extremely specialized development of the complex system comprised of the intake passages, combustion chambers, exhaust passages and valve system components."
This is how a Nextel Cup motor with 358cubes and a flat tappet cam can make more TQ than most 383 LT1's. 540ft lbs and they are tring to build HP with those motors. On top of that they are restricted to certain intake sizes due to rules on the intake manifold castings they can use.
Bret
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Joined: Oct 2002
Posts: 6,518
Originally posted by 96speed
Ken/Bret,
Are you keeping the stock hood?
What kind of TB are you using?
Ryan
Ken/Bret,
Are you keeping the stock hood?
What kind of TB are you using?
Ryan
His TB is a AS&M Monoblade, but any 58mm would work great.
Bret
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Joined: Oct 2002
Posts: 6,518
Originally posted by SS Mark
Maybe its just cause its late or that I didnt read that closely, but are you saying this intake will basically make boost? How would this work with a stock internal LT1?
Maybe its just cause its late or that I didnt read that closely, but are you saying this intake will basically make boost? How would this work with a stock internal LT1?
What happens is that the intake runners act like a organ pipe in essence. They tune for a certain frequency, and with that cause a pressure wave that if you put a gauge on the intake/head port would show a increase in port pressure much higher than atmosphereic pressure, akin to what a blower would put out. That's why I call it "faux boost" it's not really a blower at all, it's just doing the job of a well tuned intake manifold much much better than the LT1 version can do. Because we allow the motor to make much higher VE's than the stock intake does.
You can still run more compression etc.... just like any NA motor, so don't be worried about that, this "faux boost" is happening in your motor now, but at a higher RPM and at lower pressures, we are just increasing that to make more power. What's wrong with that?
That help?
Basically it's like if you had a extra 50hp, so however the stock bottom handles that. It's RPM that kills motors not HP.
Bret
Registered User
Joined: Jul 2002
Posts: 659
From: North, SC, USA
So basically, if I don't build a custom intake for my car, the best that I can do with my lt-1 intake is port match it, and go. Is this a restriction? I want to make around 400+ rwhp n/a. If there is some easy horsepower in the intake, I'll try and get it. I skipped that part during the first build, but not this one.
I've already port matched it to the heads.
I can build an aluminum intake, I have the fab stuff, so if there is a thread somewhere on the best way or blueprinted directions on how to make one, let me know.
D Moss
I've already port matched it to the heads.
I can build an aluminum intake, I have the fab stuff, so if there is a thread somewhere on the best way or blueprinted directions on how to make one, let me know.
D Moss
Advanced Tech Moderator
Joined: Aug 2001
Posts: 2,262
From: Nashville
Originally posted by dmoss69
I can build an aluminum intake, I have the fab stuff, so if there is a thread somewhere on the best way or blueprinted directions on how to make one, let me know.
D Moss
I can build an aluminum intake, I have the fab stuff, so if there is a thread somewhere on the best way or blueprinted directions on how to make one, let me know.
D Moss
http://web.camaross.com/forums/showt...hreadid=205408
Advanced Tech Moderator
Joined: Aug 2001
Posts: 2,262
From: Nashville
Originally posted by 96speed
Ken/Bret,
Are you keeping the stock hood?
Ryan
Ken/Bret,
Are you keeping the stock hood?
Ryan
Advanced Tech Moderator
Joined: Aug 2001
Posts: 2,262
From: Nashville
Originally posted by Birdie2000
Is there any benefit from this for a forced induction motor?
Is there any benefit from this for a forced induction motor?
Originally posted by SStrokerAce
the FI setup cares about flow, it does not care about intake pluse tuning, it can't because any of the faux boost created by making the intake runner lengths the correct length and correct area is negated since they are opperating in a higher than atmosphere environment. A good intake tuning pulse can be up in the 5-7psi range but a FI setup is going to be above that most likely. That's my point. That's why if someone wanted one for a FI car I would steer them away from it because I don't think it's worth the money for them when a LT1 style intake could be set up properly instead for about 1/2 the money.
Both flow and plenum volume can be beneficial to a boosted setup but the runner length and size is almost negligible.
the FI setup cares about flow, it does not care about intake pluse tuning, it can't because any of the faux boost created by making the intake runner lengths the correct length and correct area is negated since they are opperating in a higher than atmosphere environment. A good intake tuning pulse can be up in the 5-7psi range but a FI setup is going to be above that most likely. That's my point. That's why if someone wanted one for a FI car I would steer them away from it because I don't think it's worth the money for them when a LT1 style intake could be set up properly instead for about 1/2 the money.
Both flow and plenum volume can be beneficial to a boosted setup but the runner length and size is almost negligible.
Registered User
Joined: Mar 2002
Posts: 4,827
From: Waynesboro, PA
Ok, I must have missed the original thread on this thing.
Is this a modded LT1 intake or is this a custom fabbed piece???
Is it supposed to be a "bolt on" in the essence of bolting the intake to the heads???
Do you have any estimations on what this intake will do to a powerband, area under the curve, and top end???
Is this a modded LT1 intake or is this a custom fabbed piece???
Is it supposed to be a "bolt on" in the essence of bolting the intake to the heads???
Do you have any estimations on what this intake will do to a powerband, area under the curve, and top end???
Registered User
Joined: Oct 2001
Posts: 282
From: IL
Originally posted by SStrokerAce
The best way to explain this is in some old advanced tech posts on Intake Pulse Tuning.
What happens is that the intake runners act like a organ pipe in essence. They tune for a certain frequency, and with that cause a pressure wave that if you put a gauge on the intake/head port would show a increase in port pressure much higher than atmosphereic pressure, akin to what a blower would put out. That's why I call it "faux boost" it's not really a blower at all, it's just doing the job of a well tuned intake manifold much much better than the LT1 version can do. Because we allow the motor to make much higher VE's than the stock intake does.
You can still run more compression etc.... just like any NA motor, so don't be worried about that, this "faux boost" is happening in your motor now, but at a higher RPM and at lower pressures, we are just increasing that to make more power. What's wrong with that?
That help?
Basically it's like if you had a extra 50hp, so however the stock bottom handles that. It's RPM that kills motors not HP.
Bret
The best way to explain this is in some old advanced tech posts on Intake Pulse Tuning.
What happens is that the intake runners act like a organ pipe in essence. They tune for a certain frequency, and with that cause a pressure wave that if you put a gauge on the intake/head port would show a increase in port pressure much higher than atmosphereic pressure, akin to what a blower would put out. That's why I call it "faux boost" it's not really a blower at all, it's just doing the job of a well tuned intake manifold much much better than the LT1 version can do. Because we allow the motor to make much higher VE's than the stock intake does.
You can still run more compression etc.... just like any NA motor, so don't be worried about that, this "faux boost" is happening in your motor now, but at a higher RPM and at lower pressures, we are just increasing that to make more power. What's wrong with that?
That help?
Basically it's like if you had a extra 50hp, so however the stock bottom handles that. It's RPM that kills motors not HP.
Bret
Last edited by SS Mark; Jun 9, 2004 at 11:23 AM.
Advanced Tech Moderator
Joined: Aug 2001
Posts: 2,262
From: Nashville
Originally posted by Fastbird93
Ok, I must have missed the original thread on this thing.
Is this a modded LT1 intake or is this a custom fabbed piece???
Is it supposed to be a "bolt on" in the essence of bolting the intake to the heads???
Do you have any estimations on what this intake will do to a powerband, area under the curve, and top end???
Ok, I must have missed the original thread on this thing.
Is this a modded LT1 intake or is this a custom fabbed piece???
Is it supposed to be a "bolt on" in the essence of bolting the intake to the heads???
Do you have any estimations on what this intake will do to a powerband, area under the curve, and top end???
Banned
Joined: Oct 2002
Posts: 6,518
Originally posted by Fastbird93
Is this a modded LT1 intake or is this a custom fabbed piece???
Is this a modded LT1 intake or is this a custom fabbed piece???
Originally posted by Fastbird93
Is it supposed to be a "bolt on" in the essence of bolting the intake to the heads???
Is it supposed to be a "bolt on" in the essence of bolting the intake to the heads???
Originally posted by Fastbird93
Do you have any estimations on what this intake will do to a powerband, area under the curve, and top end???
Do you have any estimations on what this intake will do to a powerband, area under the curve, and top end???
Bret