Quick hp sanity check
Thread Starter
Teching In
Joined: Dec 2013
Posts: 18
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Quick hp sanity check Original plan was big power and boost, went with a stage 3 truck cam with plans too boost later. I've changed goals and want NA and a fun daily.
LQ4, 2400rpm stall, built 700r4, 3.73rear, 275/40r18 tire, truck intake, long tubes, 2.5dual exhaust with x pipe
Goal 475-500 crank
I want this to be very reliable long term so I'm trying to get quite a bit of power from as small cam as possible. Not wanting to go to double springs and aggressive lobes.
Would a lsxrt intake, BTR stage 3 truck cam(218/224, Lift .553/.553), and stage 2.5prc 706/862 heads get me there or will I need to go to a bigger cam?
Holdener seems to be at 500 with rec ports and a SS2, and or stock 706 heads, stock truck intake and a big comp 459 cam. So I'm assuming if the 2.5 PRC heads get me about the same flow as stock rec port, but almost a point higher compression, and a lsxrt intake flows better than a stock truck, it should maybe net me out around the rec port with ss2 cam? Should have PTV clearance in abundance and could mill a bit to get to 11:1 compression to help the cause.
Alternatively, given the above setup, what's the least cam I can run for 500 crank with good heads and intake on an lq
LQ4, 2400rpm stall, built 700r4, 3.73rear, 275/40r18 tire, truck intake, long tubes, 2.5dual exhaust with x pipe
Goal 475-500 crank
I want this to be very reliable long term so I'm trying to get quite a bit of power from as small cam as possible. Not wanting to go to double springs and aggressive lobes.
Would a lsxrt intake, BTR stage 3 truck cam(218/224, Lift .553/.553), and stage 2.5prc 706/862 heads get me there or will I need to go to a bigger cam?
Holdener seems to be at 500 with rec ports and a SS2, and or stock 706 heads, stock truck intake and a big comp 459 cam. So I'm assuming if the 2.5 PRC heads get me about the same flow as stock rec port, but almost a point higher compression, and a lsxrt intake flows better than a stock truck, it should maybe net me out around the rec port with ss2 cam? Should have PTV clearance in abundance and could mill a bit to get to 11:1 compression to help the cause.
Alternatively, given the above setup, what's the least cam I can run for 500 crank with good heads and intake on an lq
Last edited by SthTxLQ4; Jun 22, 2024 at 10:25 PM.
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Joined: Jan 2022
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Original plan was big power and boost, went with a stage 3 truck cam with plans too boost later. I've changed goals and want NA and a fun daily.
LQ4, 2400rpm stall, built 700r4, 3.73rear, 275/40r18 tire, truck intake, long tubes, 2.5dual exhaust with x pipe
Goal 475-500 crank
I want this to be very reliable long term so I'm trying to get quite a bit of power from as small cam as possible. Not wanting to go to double springs and aggressive lobes.
Would a lsxrt intake, BTR stage 3 truck cam(218/224, Lift .553/.553), and stage 2.5prc 706/862 heads get me there or will I need to go to a bigger cam?
Holdener seems to be at 500 with rec ports and a SS2, and or stock 706 heads, stock truck intake and a big comp 459 cam. So I'm assuming if the 2.5 PRC heads get me about the same flow as stock rec port, but almost a point higher compression, and a lsxrt intake flows better than a stock truck, it should maybe net me out around the rec port with ss2 cam? Should have PTV clearance in abundance and could mill a bit to get to 11:1 compression to help the cause.
Alternatively, given the above setup, what's the least cam I can run for 500 crank with good heads and intake on an lq
LQ4, 2400rpm stall, built 700r4, 3.73rear, 275/40r18 tire, truck intake, long tubes, 2.5dual exhaust with x pipe
Goal 475-500 crank
I want this to be very reliable long term so I'm trying to get quite a bit of power from as small cam as possible. Not wanting to go to double springs and aggressive lobes.
Would a lsxrt intake, BTR stage 3 truck cam(218/224, Lift .553/.553), and stage 2.5prc 706/862 heads get me there or will I need to go to a bigger cam?
Holdener seems to be at 500 with rec ports and a SS2, and or stock 706 heads, stock truck intake and a big comp 459 cam. So I'm assuming if the 2.5 PRC heads get me about the same flow as stock rec port, but almost a point higher compression, and a lsxrt intake flows better than a stock truck, it should maybe net me out around the rec port with ss2 cam? Should have PTV clearance in abundance and could mill a bit to get to 11:1 compression to help the cause.
Alternatively, given the above setup, what's the least cam I can run for 500 crank with good heads and intake on an lq
Thread Starter
Teching In
Joined: Dec 2013
Posts: 18
Likes: 0
While I get your point, I suppose I could've distilled my entire post down to this: If BTR is advertising 410hp @ 6000rpm on a stock 5.3 with stage 3 truck cam, would an additional 40 cubic inches of displacement, 70cfm of head flow, a full point in compression, and a FAST get me 80-90hp on the same cam?
Answer to that question, after chewing on this for a few days, is it'd be close, but I'm down to hear opinions. 2.5 706 heads flow pretty damn close to the LS3 Rec Ports, the stage 3 truck cam is on the surface pretty similar to a stock LS3, with the small chambers compression would be pretty close to a LS2/LS3 compression as well.. LS3 vettes with CAI, cat delete, longtubes, and a tune are usually around 430whp/500 crank. Also found some old 2010s posts kicking around about PRC Heads putting down 390-420 on stock cam LS1 cars.
It'd be a bit of an unusual build for sure as most people are, and for good reason really, going to be shoving in a big cam before going to upgraded heads.
Might go for it, might not, just had some thoughts dancing around and figured I'd float it out there for some guess opinions and keyboard dyno numbers
Answer to that question, after chewing on this for a few days, is it'd be close, but I'm down to hear opinions. 2.5 706 heads flow pretty damn close to the LS3 Rec Ports, the stage 3 truck cam is on the surface pretty similar to a stock LS3, with the small chambers compression would be pretty close to a LS2/LS3 compression as well.. LS3 vettes with CAI, cat delete, longtubes, and a tune are usually around 430whp/500 crank. Also found some old 2010s posts kicking around about PRC Heads putting down 390-420 on stock cam LS1 cars.
It'd be a bit of an unusual build for sure as most people are, and for good reason really, going to be shoving in a big cam before going to upgraded heads.
Might go for it, might not, just had some thoughts dancing around and figured I'd float it out there for some guess opinions and keyboard dyno numbers
Last edited by SthTxLQ4; Jun 25, 2024 at 11:51 PM.
