Why don't LS1's use BIG cams?
03-26-2005, 01:36 PM
#1
Staging Lane
Thread Starter
Join Date: Feb 2005
Location: SW Ohio
Posts: 90
Likes: 0
Received 0 Likes
on
0 Posts
Why don't LS1's use BIG cams? Having read the posts for some time now, it seems most everyone thinks a 224 @ 0.050" is some sort of wonder cam. I am sure it is a step or two better than stock, but 20 degrees of duration and 10% more lift is not a huge difference.
If most people doing a cam change are going to smaller lobe centers, obviously don't need to meet emissions, and need to get the PCM programming changed (a "tune") so the car will run right, then why not go way bigger? A 240 @ 0.050" is not big either. Why not go solid roller, 260+ @ 0.050"? Seems many go with a cylinder head upgrade too, so why not go apeshit with the cam duration and as much lift as will fit?
If most people doing a cam change are going to smaller lobe centers, obviously don't need to meet emissions, and need to get the PCM programming changed (a "tune") so the car will run right, then why not go way bigger? A 240 @ 0.050" is not big either. Why not go solid roller, 260+ @ 0.050"? Seems many go with a cylinder head upgrade too, so why not go apeshit with the cam duration and as much lift as will fit?
03-26-2005, 01:40 PM
#2
TECH Addict
iTrader: (31)
Join Date: Dec 2003
Location: Virginia Beach, Va
Posts: 2,152
Likes: 0
Received 0 Likes
on
0 Posts
for one....idle quality and driveability. not everyone can afford two cars...a daily driver and a toy. so they wanna put as much power into it they can while keeping it streetable for every day driving. two, a lot of people wanna keep the meat of their power band down lower for street use. i think a 224 is the most popular cuz its fun down low to mid range on the street and it aint exactly a puss on the high end at the track
03-26-2005, 01:43 PM
#4
TECH Addict
iTrader: (31)
Join Date: Dec 2003
Location: Virginia Beach, Va
Posts: 2,152
Likes: 0
Received 0 Likes
on
0 Posts
like i said already....driveability is the main reason. but big cams are more for track use...smaller cams are more fun on the street where your car spends most of its time in the low to mid rpm range. a higher duration is gonna give u better peak, but suffer down lower.
03-26-2005, 01:47 PM
#5
drive a car with a 260+ duration cam and you will see why...also piston to valve issues come into play unless you fly cut or do something else to get around it...which is more money...not everyone wants to, or knows how to rmaintain a solid roller setup...
03-26-2005, 01:59 PM
#6
Staging Lane
Thread Starter
Join Date: Feb 2005
Location: SW Ohio
Posts: 90
Likes: 0
Received 0 Likes
on
0 Posts
I have driven cars with 260+ duration cams. They were a lot of fun. They had big gears (4.86 and 4.56), big tires, big stall converters (4000rpm), and really came alive around 4500-5000 rpm. The big gear made up for the relative loss of low end torque. They were "old school" prostreet cars. Certainly not daily drivers -- heck I didn't like to drive them more than about 20 miles at a time. But if you are going to "go for it", why not "go big"?
With an LS1, the computer control can make any cam civil, can't it?
With an LS1, the computer control can make any cam civil, can't it?
Trending Topics
03-26-2005, 02:14 PM
#9
TECH Apprentice
Join Date: Oct 2004
Posts: 329
Likes: 0
Received 0 Likes
on
0 Posts
260@.050" IS NOT old school. For a certain power level, you have to up
the duration. You start throwing daily driver out of the window at these
camshaft levels unless you just have to drive 2 miles a day...
the duration. You start throwing daily driver out of the window at these
camshaft levels unless you just have to drive 2 miles a day...
03-26-2005, 02:21 PM
#10
Staging Lane
Thread Starter
Join Date: Feb 2005
Location: SW Ohio
Posts: 90
Likes: 0
Received 0 Likes
on
0 Posts
777 answered the question -- "things start to get un-civil after 240 duration and .625 lift..no matter who is tuning it".
One of the reasons I sold the prostreet cars was to get something more civil like my 98 Z28. From reading here, it appears that with a few bolt-ons (lid, pulley, exhaust) and a 150-shot of nitrous, this 98 Z28 could mph higher than my old prostreeters, ET almost as low, and be very easy to drive anywhere -- just like a stocker. I don't have any urge to change the cam yet.
The idle sound from a big cam is pretty cool though...
One of the reasons I sold the prostreet cars was to get something more civil like my 98 Z28. From reading here, it appears that with a few bolt-ons (lid, pulley, exhaust) and a 150-shot of nitrous, this 98 Z28 could mph higher than my old prostreeters, ET almost as low, and be very easy to drive anywhere -- just like a stocker. I don't have any urge to change the cam yet.
The idle sound from a big cam is pretty cool though...
03-26-2005, 02:28 PM
#12
King of Pigskin Knowledge
iTrader: (7)
Join Date: Dec 2002
Location: Ohio
Posts: 602
Likes: 0
Received 0 Likes
on
0 Posts
I think these guys answered it. The T-rex is the biggest I know of that you can use without fly-cutting or building a new bottom end, you run into p-v clearence issues. Also, you can only spin the stock bottom end so high without a rod or rod bolt giving out. I'm shifting at 7200 rpm with ARP rod bolts and wouldn't go any higher. As for drivability, I would daily drive the T-Rex, but I travel a lot for work, sometimes up to 14 hrs one way.
Also, there are some guys with built bottom ends that are using pretty large solid rollers.
Also, there are some guys with built bottom ends that are using pretty large solid rollers.
03-26-2005, 02:40 PM
#13
I guess the relevant question is if you feel this strongly about it, why haven't you swapped in a mondo-cam??
Originally Posted by More power!
Having read the posts for some time now, it seems most everyone thinks a 224 @ 0.050" is some sort of wonder cam. I am sure it is a step or two better than stock, but 20 degrees of duration and 10% more lift is not a huge difference.
If most people doing a cam change are going to smaller lobe centers, obviously don't need to meet emissions, and need to get the PCM programming changed (a "tune") so the car will run right, then why not go way bigger? A 240 @ 0.050" is not big either. Why not go solid roller, 260+ @ 0.050"? Seems many go with a cylinder head upgrade too, so why not go apeshit with the cam duration and as much lift as will fit?
If most people doing a cam change are going to smaller lobe centers, obviously don't need to meet emissions, and need to get the PCM programming changed (a "tune") so the car will run right, then why not go way bigger? A 240 @ 0.050" is not big either. Why not go solid roller, 260+ @ 0.050"? Seems many go with a cylinder head upgrade too, so why not go apeshit with the cam duration and as much lift as will fit?
03-26-2005, 04:03 PM
#15
Staging Lane
Thread Starter
Join Date: Feb 2005
Location: SW Ohio
Posts: 90
Likes: 0
Received 0 Likes
on
0 Posts
No really big cam for me; maybe a little bigger in the future. Main reasons:
I need to meet emissions, wish to avoid the extra cost of a "tune" if possible, I don't like the smell of raw fuel from a cam with lots of overlap at idle, and I don't intend to make a race car out of this Camaro, and I have a "goal" to see how fast the car will go with the stock cam before tearing into the engine.
Thanks!
I need to meet emissions, wish to avoid the extra cost of a "tune" if possible, I don't like the smell of raw fuel from a cam with lots of overlap at idle, and I don't intend to make a race car out of this Camaro, and I have a "goal" to see how fast the car will go with the stock cam before tearing into the engine.
Thanks!
Last edited by More power!; 03-27-2005 at 11:03 AM.
03-26-2005, 04:36 PM
#16
The short answer is that the guys who can afford to have a track only car with large solid rollers and bigger cubes and carbed manifolds already have done those things... there's plenty of track only late model F-bodies out there running big solid rollers.
The vast majority of us, however, want to have a car that's at least somewhat driveable on the street... most of us don't want our cars sitting in the garage or on a trailer 99.99% of the time... so you give up having a more radical more all-out setup for one that's a compromise. Good power increase with decent driveability...
The vast majority of us, however, want to have a car that's at least somewhat driveable on the street... most of us don't want our cars sitting in the garage or on a trailer 99.99% of the time... so you give up having a more radical more all-out setup for one that's a compromise. Good power increase with decent driveability...
03-26-2005, 07:34 PM
#17
TECH Apprentice
iTrader: (3)
Join Date: Aug 2004
Location: Largo, Fl.
Posts: 370
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by More power!
Umm, I would have to answer the personal stabs (why don't you do it) that I need to meet emissions, I plan to avoid the extra cost of a "tune" if possible, I don't like the smell of raw fuel from a cam with lots of overlap at idle, and I don't intend to make a race car out of this Camaro.
03-26-2005, 07:46 PM
#18
There was no crankiness or offense in what I posted, just pressing the issue to see if your intent in the post was real or wasting time.
And "why don't you do it?" is a question, not advice.
And "why don't you do it?" is a question, not advice.
Originally Posted by More power!
Umm, I would have to answer the personal stabs (why don't you do it) that I need to meet emissions, I plan to avoid the extra cost of a "tune" if possible, I don't like the smell of raw fuel from a cam with lots of overlap at idle, and I don't intend to make a race car out of this Camaro.
Jeez, I make an observation, ask a question, and some folks get all cranky.
Some people like to find out why there seem to limits on some aspects of the LS1 engine. This seems to offend some folks. Never thought of the reply to a question you don't know the answer for as being -- "well why don't you do it?" Great advice.
Thanks to all who gave the information sharing replies!
Jeez, I make an observation, ask a question, and some folks get all cranky.
Some people like to find out why there seem to limits on some aspects of the LS1 engine. This seems to offend some folks. Never thought of the reply to a question you don't know the answer for as being -- "well why don't you do it?" Great advice.
Thanks to all who gave the information sharing replies!
03-27-2005, 12:55 AM
#19
Banned
iTrader: (1)
Join Date: Nov 2004
Location: North of Seattle
Posts: 2,057
Likes: 0
Received 0 Likes
on
0 Posts
Depends on what you consider big. I think my cam, although sounding pretty mean, with a tune is as civil and has just as much grunt down low as the stocker. After tuning i can't really tell a difference in the driveablility.
As far as your statement goes, i think you worded it incorrectly as to make your desired point. Go hang out in the drag racing forum and look at a few signatures. You'll rethink your statement.
Nate
As far as your statement goes, i think you worded it incorrectly as to make your desired point. Go hang out in the drag racing forum and look at a few signatures. You'll rethink your statement.
Nate
03-27-2005, 01:07 AM
#20
TECH Fanatic
iTrader: (1)
Join Date: Nov 2003
Location: Gardnerville, NV.
Posts: 1,037
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by crainholio
There was no crankiness or offense in what I posted, just pressing the issue to see if your intent in the post was real or wasting time.
And "why don't you do it?" is a question, not advice.
And "why don't you do it?" is a question, not advice.
My advice, if you're going to hang out on boards and ask provacotive questions don't act like you've been malined when people give the answer you proabably expected.
You got a lot of good answers and a few people called BS and gave you their honest response. Nobody attacked you or "stabbed" you.
