What cam and what CID?
Thread Starter
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
What cam and what CID?
First, what CID:
LS6 Heads ported/valve job for velocity
LS6 Intake ported w/ported stock TB
1 3/4 inch LG Longtubes
Forged rods and pistons in the 11:1 comp area
346, 383, LS2, etc?
Based on above (inc recommended CID):
What cam:
300+ shot of nitrous will be used
Want to maximize nitrous ability of cam (not worried about NA ability)
And the big one:
Do NOT want a lumpy, hard to idle cam. I like it almost non-existent....
What's the tech section recommend? I'm just trying to see how closely you guys align with my "plans."
Thanks.
LS6 Heads ported/valve job for velocity
LS6 Intake ported w/ported stock TB
1 3/4 inch LG Longtubes
Forged rods and pistons in the 11:1 comp area
346, 383, LS2, etc?
Based on above (inc recommended CID):
What cam:
300+ shot of nitrous will be used
Want to maximize nitrous ability of cam (not worried about NA ability)
And the big one:
Do NOT want a lumpy, hard to idle cam. I like it almost non-existent....
What's the tech section recommend? I'm just trying to see how closely you guys align with my "plans."
Thanks.
Drifting
Joined: Nov 2003
Posts: 1,539
Likes: 3
From: South al
First, what CID:
LS6 Heads ported/valve job for velocity
LS6 Intake ported w/ported stock TB
1 3/4 inch LG Longtubes
Forged rods and pistons in the 11:1 comp area
346, 383, LS2, etc?
Based on above (inc recommended CID):
What cam:
300+ shot of nitrous will be used
Want to maximize nitrous ability of cam (not worried about NA ability)
And the big one:
Do NOT want a lumpy, hard to idle cam. I like it almost non-existent....
What's the tech section recommend? I'm just trying to see how closely you guys align with my "plans."
Thanks.
LS6 Heads ported/valve job for velocity
LS6 Intake ported w/ported stock TB
1 3/4 inch LG Longtubes
Forged rods and pistons in the 11:1 comp area
346, 383, LS2, etc?
Based on above (inc recommended CID):
What cam:
300+ shot of nitrous will be used
Want to maximize nitrous ability of cam (not worried about NA ability)
And the big one:
Do NOT want a lumpy, hard to idle cam. I like it almost non-existent....
What's the tech section recommend? I'm just trying to see how closely you guys align with my "plans."
Thanks.
Thread Starter
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
300 SHOT none of the Above, I would However use a 370 ci Iron Block Or a 408 Iron Block ,I dont know how many Times u will be able to Spray A 300 Shot of Nitrous on it & it not come apart unless u go Forged Rods & Forged Pistons Your Stock Crank may be ok ,with the 346 ,383 or the Ls2 ,i would consider a High Lsa if u Dont want a lumpy cam jmo
Drifting
Joined: Nov 2003
Posts: 1,539
Likes: 3
From: South al
Yes that is what Texas speed recommend /Jon ,he told me that the Iron Blocks are gonna be Stronger than the aluminum but the aluminum will take the abuse ,he had twin turbo car with a 402 ,that made 1000rwhp & he had no girdle ,so it all is gonna go back to what kinda power your looking to get out of it ,i would think that the 346,383 364,will make north of 750 rwhp with the right setup that is with Fi /Nitrous /Blower/Turbo,u will have to go forged on these motors to spray 300 on it if u intend on spraying it everyweekend @ the Dragstrip,i think u can spray 300 shot on the stock bottom end ,i dont know how many times u will be able to do this without it coming apart,I have a Friend who owns an 02 Ls6 ,He was getting on it pretty good Driving it on the street & had a rod bolt come loose ,his rod came thru the block,this happend 3 days ago ,he is also looking to go with a 402 forged setup ,I also like the idea of going with a stroked motor to make more tq down low ,although when going big uhave to take in account ,big means ,$$$$ more money ,bigger headers ,Better Airflow a head change would be recommended if u are going bigger ,Although the 1&3/4 headers & the 5.7 ltr heads will fit on the 6.0 or the 6.6 ,it will be like trying to suck a whopper thru a coca cola straw
Last edited by fsuforever; Oct 6, 2007 at 11:05 AM.
Le Mans Master
Joined: Feb 2006
Posts: 5,488
Likes: 4
From: USA
So are you saying Higgs would be O.K. without forged rods and pisons if he didn't go with the 300+ shot of nitrous? Seems like he would unless he wants big numbers.
Drifting
Joined: Nov 2003
Posts: 1,539
Likes: 3
From: South al
ya he would be ok without Going forged, but he wont be able to spray a 300 shot on the Block & let it maintain realiabilty for any length of time ,But if u are gonna build a motor why wouldnt u put forged back in it?I Dont know of anybody that would build a motor to put it back stock if u plan on running Nitrous on it ,Do u ?
Team Owner
Joined: Nov 2001
Posts: 34,124
Likes: 105
From: Pensacola FL
Even though I have a 383 LSx in my Z28, I'm going to say 402 or 408. There is little differnce in cost, you get the extra cubes AND the larger bore allows for big valves with less shrouding. I have yet to hear of a Al LSx block splitting, so I think that iron is overkill and extra weight for 750-800rwhp. The iron may retain shape and hold the heads a little better, but negligible at that power from what I've seen/read. Both cams I've used in the LSx with nitrous have had a little more exhaust duration and have worked well. Good luck!
Thread Starter
Race Director
Joined: Jul 2007
Posts: 10,961
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From: Texas Hill Country
I am confused to whether you read my post or not, lol. I AM building a forged internal shortblock. I am using my LS6 heads. I am using the headers I already have on the car, etc. Currently the car makes 500 RWHP/530 RWTQ on a 150 shot. I want to build a mild cammed motor making around 430 RWHP NA and spray bigger and want it to not blow up. I cannot do this on my stock shortblock. My questions are:
What displacement do I use given the parts I am keeping and what cam do I use given the parts I am using AND given the recommended displacement? Obviously, 346, 383, LS2, etc is only a reference to different potential CIDs.... All are alum blocks. I could put an iron 408 in the list. That's why I am asking...... If my top end won't flow sufficiently for a stroker then I will build a forged 350... I don't care what CID it is as long as it's not too big for my heads and intake....
What displacement do I use given the parts I am keeping and what cam do I use given the parts I am using AND given the recommended displacement? Obviously, 346, 383, LS2, etc is only a reference to different potential CIDs.... All are alum blocks. I could put an iron 408 in the list. That's why I am asking...... If my top end won't flow sufficiently for a stroker then I will build a forged 350... I don't care what CID it is as long as it's not too big for my heads and intake....
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Thread Starter
Race Director
Joined: Jul 2007
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From: Texas Hill Country
Even though I have a 383 LSx in my Z28, I'm going to say 402 or 408. There is little differnce in cost, you get the extra cubes AND the larger bore allows for big valves with less shrouding. I have yet to hear of a Al LSx block splitting, so I think that iron is overkill and extra weight for 750-800rwhp. The iron may retain shape and hold the heads a little better, but negligible at that power from what I've seen/read. Both cams I've used in the LSx with nitrous have had a little more exhaust duration and have worked well. Good luck!
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
The larger the displacement of the engine, the more nitrous you can run thru it without detrimental effect.
In other words, with the larger shots, say 300 like you're wanting to spray, the effect will be worse on a 346 than it will on a 403. And so on as you increase in size.
As for cams, run as much lift as possible, while maintaining proper valvetrain geometry, and within the limits of your valve springs.
As for exact numbers, you can jack around the duration and LSA til you get the overlap you want or need.
If you want no lope, or very little, stick with an overlap number close to zero @ .050
You could probably go as much as +5 without much lope. But it will have some as long as you're on the plus side.
Trying to choose a cam with NO lope and "maximize the nitrous" at the same time will be next to impossible. You will be compromising, and giving up a little of something, or more likely, a little of both.
In other words, with the larger shots, say 300 like you're wanting to spray, the effect will be worse on a 346 than it will on a 403. And so on as you increase in size.
As for cams, run as much lift as possible, while maintaining proper valvetrain geometry, and within the limits of your valve springs.
As for exact numbers, you can jack around the duration and LSA til you get the overlap you want or need.
If you want no lope, or very little, stick with an overlap number close to zero @ .050
You could probably go as much as +5 without much lope. But it will have some as long as you're on the plus side.
Trying to choose a cam with NO lope and "maximize the nitrous" at the same time will be next to impossible. You will be compromising, and giving up a little of something, or more likely, a little of both.
Team Owner
Joined: Nov 2001
Posts: 34,124
Likes: 105
From: Pensacola FL
So a forged LS2 shortblock with my heads and intake and whatever cam will be the ticket according to this, right? Ok, so I know more CID equals more cam. But what about the difference for an NA cam vs a nitrous cam? Do I want a lot more exhaust vs intake or what? This will also determine how I work the heads....
What will be your primary goal for this set-up?
What power level (roughly) are you shooting for?
There are SOOO many options right now for a LSx build, that your ends will make the means easier to nail down...
Team Owner
Joined: Nov 2001
Posts: 34,124
Likes: 105
From: Pensacola FL
The larger the displacement of the engine, the more nitrous you can run thru it without detrimental effect.
In other words, with the larger shots, say 300 like you're wanting to spray, the effect will be worse on a 346 than it will on a 403. And so on as you increase in size.
As for cams, run as much lift as possible, while maintaining proper valvetrain geometry, and within the limits of your valve springs.
As for exact numbers, you can jack around the duration and LSA til you get the overlap you want or need.
If you want no lope, or very little, stick with an overlap number close to zero @ .050
You could probably go as much as +5 without much lope. But it will have some as long as you're on the plus side.
Trying to choose a cam with NO lope and "maximize the nitrous" at the same time will be next to impossible. You will be compromising, and giving up a little of something, or more likely, a little of both.
In other words, with the larger shots, say 300 like you're wanting to spray, the effect will be worse on a 346 than it will on a 403. And so on as you increase in size.
As for cams, run as much lift as possible, while maintaining proper valvetrain geometry, and within the limits of your valve springs.
As for exact numbers, you can jack around the duration and LSA til you get the overlap you want or need.
If you want no lope, or very little, stick with an overlap number close to zero @ .050
You could probably go as much as +5 without much lope. But it will have some as long as you're on the plus side.
Trying to choose a cam with NO lope and "maximize the nitrous" at the same time will be next to impossible. You will be compromising, and giving up a little of something, or more likely, a little of both.
Thread Starter
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
Well I just bought the 1 3/4 LGs and I'm not changing!!
I have no problem making less power if that's what I have to do. My first priority is working with the parts I already said I am keeping. That's why I do not have a power level in mind. Whatever it comes to, that's what it will be....
I have no problem making less power if that's what I have to do. My first priority is working with the parts I already said I am keeping. That's why I do not have a power level in mind. Whatever it comes to, that's what it will be....
Drifting
Joined: Nov 2003
Posts: 1,539
Likes: 3
From: South al
But if The Pockets arent Deep enough to do that ,then it cant be done @ This Time ,That Doesnt mean he cant Buy a Sb & Have the 1 & 3/4 go on them & When he does get the money take them suckers off & put the 1 &7/8 on ,i am having to do this with a 402 , i just dont have xtra money to buy 1&7/8 Kooks Hdrs,I would love to have them ,but i have 5k in a Shortblock that i dont even have the oilpan on yet or the timing chain ,I will its just a matter of time
Thread Starter
Race Director
Joined: Jul 2007
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From: Texas Hill Country
I would have thought you guys would crucify me for using the stock intake and TB before the LTs....
What is the max HP the 1 3/4 headers can support before they are a restriction?
What is the max HP the ported LS6 intake/TB can support before restricting power?
What is the max HP the 1 3/4 headers can support before they are a restriction?
What is the max HP the ported LS6 intake/TB can support before restricting power?
Drifting
Joined: Dec 2003
Posts: 1,586
Likes: 72
From: Upstate NY
Crucify you???? When have you ever seen anyone on this board be less than cordial in any of the posts you read? Everyone is extremely respectful here
Just reread your post....and I wouldn't know at what HP level they become a restriction. I'm sure there are those on this board who are much more knowledgeable than I that can answer that question.
Last edited by H82GOSLW; Oct 7, 2007 at 08:51 PM.
Thread Starter
Race Director
Joined: Jul 2007
Posts: 10,961
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From: Texas Hill Country
Crucify you???? When have you ever seen anyone on this board be less than cordial in any of the posts you read? Everyone is extremely respectful here
Just reread your post....and I wouldn't know at what HP level they become a restriction. I'm sure there are those on this board who are much more knowledgeable than I that can answer that question.
Just reread your post....and I wouldn't know at what HP level they become a restriction. I'm sure there are those on this board who are much more knowledgeable than I that can answer that question.
It's the internet!!