408 Stroker/6.7 LQ9 Escalade EXT
11-12-2018, 06:46 AM
#1
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408 Stroker/6.7 LQ9 Escalade EXT 
Hello I have a Caddy EXT with a fbo forged 408 LQ9 flattop Cp pistons with pnp 799s and a Ported Tbss intake 238/246 109 cam. I've been told since I have bigger cubes I need to go square port right now my truck made 450rwhp and 418rw thru a built and stalled 4l80 2wd. All this time I've been chasing HP and now learning torque plays a big part having a 6000lb land yatch. I really would like to get in the 500whp and nice torque that would get this baby moving before going F/I. Track times is terrible 9.2 in the 8th trapping 72mph (not expecting to run 9s in this thing) I was getting toasted by fbo and tune only pick ups 🤦🏾. what set up you guys suggest?
11-12-2018, 09:27 AM
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11-12-2018, 04:19 PM
#4
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I'm not versed on procharger sizes, but I think you'll want a large one lol......
it's my belief that when you start this far behind the 8-ball(extremely heavy vehicle) to get great gains, you need to look into large amounts of boost.
I dont onow what a lsa blower will max out, but would require the head change your considering, or at least adapters.
procharger sure does sound cool.....
it's my belief that when you start this far behind the 8-ball(extremely heavy vehicle) to get great gains, you need to look into large amounts of boost.
I dont onow what a lsa blower will max out, but would require the head change your considering, or at least adapters.
procharger sure does sound cool.....
11-12-2018, 08:21 PM
#5
TECH Resident
Cathedral are good for low rpm torque and rectangular are good for high rpm hp. There are some big aftermarket cathedral that would be great for your application, but at the price point you'll be most of the way to a supercharger or turbo which will get you even more power. If you go boosted rectangular is the way to go since it'll move more cfm.
11-13-2018, 07:46 AM
#6
But even a 9.2 @ 72mph seems really REALLY slow for a mild 6.0, that cam is fairly large for a truck and will be sluggish down low especially with the taller 1st gear of the 4l80e unless you have a 3500+ stall or say a 4.56 gear.
What Rpm is it shifting at? and what stall are you running?
If it were me and I had the MONEY Id swap the cam and throw a turbo on it , 15lbs of boost would get you a reliable 750 ish at the wheel with good fuel and tune. Or any other way you wanna boost it they will all cost about the same if you do it right.
Last edited by Ls7colorado; 11-13-2018 at 08:08 AM.
11-13-2018, 08:44 AM
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Cathedral heads will be more than enough head flow for a boosted application, especially his ported 243's and will give better low end like stated above witch he needs with a 5500lb truck
But even a 9.2 @ 72mph seems really REALLY slow for a mild 6.0, that cam is fairly large for a truck and will be sluggish down low especially with the taller 1st gear of the 4l80e unless you have a 3500+ stall or say a 4.56 gear.
What Rpm is it shifting at? and what stall are you running?
If it were me and I had the MONEY Id swap the cam and throw a turbo on it , 15lbs of boost would get you a reliable 750 ish at the wheel with good fuel and tune. Or any other way you wanna boost it they will all cost about the same if you do it right.
But even a 9.2 @ 72mph seems really REALLY slow for a mild 6.0, that cam is fairly large for a truck and will be sluggish down low especially with the taller 1st gear of the 4l80e unless you have a 3500+ stall or say a 4.56 gear.
What Rpm is it shifting at? and what stall are you running?
If it were me and I had the MONEY Id swap the cam and throw a turbo on it , 15lbs of boost would get you a reliable 750 ish at the wheel with good fuel and tune. Or any other way you wanna boost it they will all cost about the same if you do it right.
Last edited by Cadillac_Edd; 11-13-2018 at 08:50 AM.
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11-13-2018, 08:59 AM
#8
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Hello I have a Caddy EXT with a fbo forged 408 LQ9 flattop Cp pistons with pnp 799s and a Ported Tbss intake 238/246 109 cam. I've been told since I have bigger cubes I need to go square port right now my truck made 450rwhp and 418rw thru a built and stalled 4l80 2wd. All this time I've been chasing HP and now learning torque plays a big part having a 6000lb land yatch. I really would like to get in the 500whp and nice torque that would get this baby moving before going F/I. Track times is terrible 9.2 in the 8th trapping 72mph (not expecting to run 9s in this thing) I was getting toasted by fbo and tune only pick ups 🤦🏾. what set up you guys suggest?
11-13-2018, 04:15 PM
#9
TECH Resident
After watching the video I'd start by pulling the running boards and changing the wheels. That thing is huge to start with and adding weight isn't helping you any. Unsprung weight is the worst and that's all your wheels are.
11-13-2018, 04:55 PM
#10
TECH Fanatic
I would call one of the "cam" designing experts and have them spec you a camshaft. IMO the cam you are running is way wrong for a heavy vehicle. I think your setup would benefit more from something more like 222/228 .590/.590 114 +4 .
Torque is what you should be looking for with your heavy truck, build high torque , and HP will follow with the foundation you are building
Torque is what you should be looking for with your heavy truck, build high torque , and HP will follow with the foundation you are building
11-13-2018, 07:59 PM
#11
I have a similar heavy setup with a 2500 6.0 suburban running a BTR stage 3 truck cam, 243 heads milled and ported, TBSS, 4.56 with TrueTrac, and 1 7/8 headers, E-fans and all. Weight is truly our enemy. I'm right there with you at a 76 mph trap and I'm stock displacement. Get a cheap set of 16 inch aluminum wheels for racing.
To get real speed requires boost or juice. Since your bottom end is built a procharger is easiest for boost. The Fa1 would be awesome. Turbo has more potential and possibly cheaper but more work. N2O is the quick and dirty way. Keep us posted so we can see how it does.
To get real speed requires boost or juice. Since your bottom end is built a procharger is easiest for boost. The Fa1 would be awesome. Turbo has more potential and possibly cheaper but more work. N2O is the quick and dirty way. Keep us posted so we can see how it does.
11-13-2018, 10:41 PM
#12
Just by listening to that run the stall is not flashing high enough for that cam, and it is shifting at what sounds like 5500 ish rpm? Could be wrong but it sounded very low.
those heavy tall wheels are Probabaly costing you a few mph and a few tenths also.
those heavy tall wheels are Probabaly costing you a few mph and a few tenths also.
Last edited by Ls7colorado; 11-14-2018 at 06:05 AM.
11-14-2018, 12:26 AM
#13
TECH Senior Member
Racing this overdressed Avalanche is like taking a 747 air racing....
11-14-2018, 06:26 AM
#14
A Whipple or magunson 2300 or 2900 blower for torque down low to get that weight moving out of the hole and a corresponding camshaft for your application would be my advice setup. Fasterproms(jeremy formato) just did a setup like that on his escalade and it runs 10s I believe.
11-14-2018, 10:03 AM
#15
OP what was the 60 foot time?
I definitely agree with the others different wheels wheels for the track will help.
Maybe if there is enough piston to valve clearance, degreeing in the current cam with 2 to 4 more degrees of advance would help as a band-aid to bring the power on sooner and move the torque curve lower in the rpm range. I'm not sure on the P to V clearance with that big of cam. Hopefully some of the more expert members like JoeNova, Darth, PooterSS, Chevelle, KCS and many others will comment.
For what it's worth, NA I think the cam is too big for getting a heavy SUV off of the line. My 416 has a custom cam by Darin Morgan from Reher-Morrison that makes 400 wtq at 2,800 rpm, 450 wtq by mid 3,000 rpm's and has great stupid fat truck friendly torque curve. With the current set up, I think a custom cam by someone like Darin Morgan or Cam Motion will get the torque curve where your SUV needs it.
I definitely agree with the others different wheels wheels for the track will help.
Maybe if there is enough piston to valve clearance, degreeing in the current cam with 2 to 4 more degrees of advance would help as a band-aid to bring the power on sooner and move the torque curve lower in the rpm range. I'm not sure on the P to V clearance with that big of cam. Hopefully some of the more expert members like JoeNova, Darth, PooterSS, Chevelle, KCS and many others will comment.
For what it's worth, NA I think the cam is too big for getting a heavy SUV off of the line. My 416 has a custom cam by Darin Morgan from Reher-Morrison that makes 400 wtq at 2,800 rpm, 450 wtq by mid 3,000 rpm's and has great stupid fat truck friendly torque curve. With the current set up, I think a custom cam by someone like Darin Morgan or Cam Motion will get the torque curve where your SUV needs it.
Last edited by 99 Black Bird T/A; 11-14-2018 at 10:19 AM.
11-14-2018, 10:41 AM
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or is the avalanche a underdressed EXT since Chevy came 10 years after cadillac. But I understand the weight issue. but this is my dream truck. I want to make it fast. I could easily get a s10 if I want a easy truck to work with. Help me, i don't need pointless comments like that.
11-14-2018, 10:43 AM
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OP what was the 60 foot time?
I definitely agree with the others different wheels wheels for the track will help.
Maybe if there is enough piston to valve clearance, degreeing in the current cam with 2 to 4 more degrees of advance would help as a band-aid to bring the power on sooner and move the torque curve lower in the rpm range. I'm not sure on the P to V clearance with that big of cam. Hopefully some of the more expert members like JoeNova, Darth, PooterSS, Chevelle, KCS and many others will comment.
For what it's worth, NA I think the cam is too big for getting a heavy SUV off of the line. My 416 has a custom cam by Darin Morgan from Reher-Morrison that makes 400 wtq at 2,800 rpm, 450 wtq by mid 3,000 rpm's and has great stupid fat truck friendly torque curve. With the current set up, I think a custom cam by someone like Darin Morgan or Cam Motion will get the torque curve where your SUV needs it.
I definitely agree with the others different wheels wheels for the track will help.
Maybe if there is enough piston to valve clearance, degreeing in the current cam with 2 to 4 more degrees of advance would help as a band-aid to bring the power on sooner and move the torque curve lower in the rpm range. I'm not sure on the P to V clearance with that big of cam. Hopefully some of the more expert members like JoeNova, Darth, PooterSS, Chevelle, KCS and many others will comment.
For what it's worth, NA I think the cam is too big for getting a heavy SUV off of the line. My 416 has a custom cam by Darin Morgan from Reher-Morrison that makes 400 wtq at 2,800 rpm, 450 wtq by mid 3,000 rpm's and has great stupid fat truck friendly torque curve. With the current set up, I think a custom cam by someone like Darin Morgan or Cam Motion will get the torque curve where your SUV needs it.
11-14-2018, 10:50 AM
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i was thinking about taking them off for looks but do the actually weight much? I thought they was plastic plus I'm 6'2 I never step on them lol
11-14-2018, 10:58 AM
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I have a similar heavy setup with a 2500 6.0 suburban running a BTR stage 3 truck cam, 243 heads milled and ported, TBSS, 4.56 with TrueTrac, and 1 7/8 headers, E-fans and all. Weight is truly our enemy. I'm right there with you at a 76 mph trap and I'm stock displacement. Get a cheap set of 16 inch aluminum wheels for racing.
To get real speed requires boost or juice. Since your bottom end is built a procharger is easiest for boost. The Fa1 would be awesome. Turbo has more potential and possibly cheaper but more work. N2O is the quick and dirty way. Keep us posted so we can see how it does.
To get real speed requires boost or juice. Since your bottom end is built a procharger is easiest for boost. The Fa1 would be awesome. Turbo has more potential and possibly cheaper but more work. N2O is the quick and dirty way. Keep us posted so we can see how it does.
11-14-2018, 11:04 AM
#20
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or is the avalanche a underdressed EXT since Chevy came 10 years after cadillac. But I understand the weight issue. but this is my dream truck. I want to make it fast. I could easily get a s10 if I want a easy truck to work with. Help me, i don't need pointless comments like that.
If you swap to lighter wheels at the track you'll gain around a tenth. Pull sound deadener and gain more. If you never adjust the seat swap in a manual track and gain some more. Lower it a couple inches and you'll cut wind resistance and you won't need the side steps. There's a laundry list of things you can do to drop weight and improve performance that nobody would ever notice if you don't point it out to them.