99ZEOD

iTrader: (5)

WOW! This got way out of control. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> I saw one person take a jab at the original question and a few novels about cams. Good info but kinda strayed a bit. I'd like to know the gains of slapping a set on there as well. Anybody?

Jay

1madss

iTrader: (10)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">--------------------------------------------------------------------------------
You guys buying single pattern cams are messing up!
--------------------------------------------------------------------------------

Would you care to elaborate? </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Please do. I have seen the single pattern cams putting down the numbers, not just ET, but MPH also. I have yet to see that the dual pattern cams have that much of an advantage over a single pattern. This has been a hot topic for quite some time.

Basically, put up <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

LS1 Kyle

He will put up. Give him some time to get a few things going. The single pattern cam issue exists to keep the computer from freaking out. Even though I currently don't have any motor work, I will never go with a single pattern cam, ever...

Why?? Because it's a compromise for those who want gains without the hassle of custom computer programming, emission testing concerns, or drivability issues.

The real point here is that over 90% of us on this board, excluding jmx (sorry Jon) <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> , are concerned with how fast our car goes in the 1/4. So for me, I'm taking the route that gets me there and I believe that Jay has the right approach...

Kyle

<small>[ March 26, 2002, 10:59 PM: Message edited by: LS1 Kyle ]</small>

Jason99T/A

iTrader: (21)

Here is what Chris 98 SS gained by adding a set of GTP stage 2 heads to his car.

http://www.thunderracing.com/images/chris_gtp1.jpg

Here is the thread:
https://ls1tech.com/ubb/cgi-bin/ulti...c;f=1;t=003086

jmX

Hrm, theory intermingles with reality here. Look.....ploting crap out on a computer simulation or applying stuff from 30 year old cars sometimes doesnt always pan out.

All I'm saying is that I've had 4 ls1 cams:
218/224 (114lsa)
230/230 (112lsa)
224/230 (114lsa)
224/224 (114lsa)

and of all of them, the 224/224 ran the best. They all put down the exact same peak RWHP, the 224/224 had the best lowend torque. Theory is all fine and dandy, but it sure as heck didn't pay off in my situation.

Holes02

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by LS1 Kyle:
<strong>The real point here is that over 90% of us on this board, excluding jmx (sorry Jon) <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> , are concerned with how fast our car goes in the 1/4. So for me, I'm taking the route that gets me there and I believe that Jay has the right approach...</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">But aren't the lists of all the top cars proof that split pattern cams aren't necessarily GOING to make you get there any quicker? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
As of late, single pattern cams have been kicking *** and taking names not only on the dyno, but on the track as well. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

BIGBOS

Thats why in the future IF I stay motor I want to go to a bigger single pattern or try out that G5, I want to see some more G5 results though, but the 226/226 cam has sounded nice, maybe even step up to a little split 228/232 <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

RPM WS6

iTrader: (3)

Singles perform on LS1s. The numbers don't lie. I could care less what works well on old carbed SBCs.

There are still gains to be had with cutsom tuning on a single pattern.

Yes, it's true that there is a big market for singles for LS1s. Why do you think that is? Maybe cause they work???

CHRISPY

Spilt patterns do work guys <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Look at ONYXSS he has run 123mph in a 3550 raceweight HCI car. His cam is the same as mine 226/234 112LSA and 554/575 lift. I haven't run with my new combo yet but it is DEFINITELY making more power over my old combo even on stock tuning.

The MAIN reason singles are used are for drivability and emissions period. There isnt anything magical about a single pattern vs dual pattern except those points I mentioned above. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Also I am surprised people havent tried split patterns favoring the intake side to get over the intake restriction in our motors. I wonder how a 228/224 .588/.581 lift 112LSA cam would work? I bet it would work really well ESPECIALLY if the exhaust system is well thought out and not in need of huge duration numbers to the the spent charge out.
Cheers,
Chris

LS1 Kyle

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">...
Yes, it's true that there is a big market for singles for LS1s. Why do you think that is? Maybe cause they work???</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks for restating what I've already said. I agree that the single patterns are getting results but "I" believe there are better gains to be had by using a split pattern.

I think this is what Jay and Chris are getting at...

Kyle

<small>[ March 27, 2002, 08:43 AM: Message edited by: LS1 Kyle ]</small>

1madss

iTrader: (10)

Guys,
Nobody is saying that the split pattern do not work. The statement is that dual pattern cams have not proven themselves to make more power than the single patterns. Why deal with the problems of a dual pattern if it does not make more power? If the dual patterns do show that they are a better cam then I'm sure that a lot of people while consider going that route. Until then, I will stick with my proven performing "mistake" <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

RPM WS6

iTrader: (3)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 1madss:
<strong>Guys,
Nobody is saying that the split pattern do not work. The statement is that dual pattern cams have not proven themselves to make more power than the single patterns. Why deal with the problems of a dual pattern if it does not make more power? If the dual patterns do show that they are a better cam then I'm sure that a lot of people while consider going that route. Until then, I will stick with my proven performing "mistake" <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Exactly! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

ChrisB

I will say right now when you get down to it a single pattern cam will not give you the best power/perfromance across the board. Why? Because your intake and exhaust events are so different, that the odds they would have exactly the same lobe requirements are infintessimal. They might actually want a 224/226 or 224/224.65 or 224/224 but on different lobes, or a 225/224, etc.

Now throw into the mix different heads, exaust systems, etc. 2 heads that "flow" the same may work better with different camshafts because of other characteristics. - one person may be running a weaker exhaust and need to crutch it a little more with more cam duration - on person may have a more free flowing exhaust and not need the extra valve open time.

So what's the point? Purely from a theory standpoint a split pattern will make more power. That's an easy statement. Now the hard part is which split? Since there are so many possible choices that's not any easy question. And on split isn't as good as another - you can very easily have a split duration camshaft that looses power vs a single patter - simply because you chose the wrong split.

Single patterns are popular because they pretty much just work. You are hedging your bet. you may be leaving 5hp at the table, but you are probably picking up a little better drivability and low end torque. And if you have a strong exhaust side you probably aren't giving up much at all.

I don't disagree that in theory a split pattern cam is the way to go - I just disagree with lumping all split patter cams together and saying, based on that theory, I will just throw a couple of extra degrees on the exhaust. (which seems to me to be the general case).

The other point - head flow capabilities vary by a decent amount - not just flow numbers, but cross sectional area, port shape, etc. This is going to directly impact cam timing also.

Finally as Tim pointed out, valve events are probably more important than duration numbers, etc. they actually define when in the cycle the vavle's are opening/closing, and this has a huge impact on how it all works also.

Chris

JAMCAM

Chris at Spped Demon, thanks for taking my entire post and try to pick it apart. I have spent months upon months on dynos. Both engine with the pro stock stuff and dynojets with NASCAR stuff. In both cases, acceleration = ET. Power is something that sells parts. You MUST have a chassis dyno and I stepped on your toes. Warren Johnson who I respect carries a power speed calculator too. Now, he's NOT God, but if REAL racers, not theorist use them, give it a try. The single pattern cam thing. Look in 95% of the cam books. They are mostly single pattern or very small spread cams. because the AVERAGE guy does not know better. What gets the intake charge moving? A differential in pressure because of the exhaust scavaging, right? Thus, if the exhaust is SO import, why not high light it? Proof, take the exhaust off any LS1, why does it go faster? A much better pulse through the exhaust on the intake track. I have SEVERAL designs currently that I am TAKING TO THE TRACK. It will be EASY to pass emissions, maintain excellent drivaability and surpass the current cam stuff. Now don't get me wrong, Scooter Borthers (owner at Comp Cams in case you didn't know) is a great guy. Their stuff for the average guy is great. You can deal with them, I want to have the fastest cars, not just fast ones.
Now, I do not need my post sent back picked apart. If you'd like, I'd LOVE, I MEAN LOVE to talk back and forth about this junk. Please, either call me, or e-mail me your number and I will call you anytime. And no sir, power under the curve does not = ET. Please contact me at 734.439.0134. I look forward to a good conversation. Sincerely...Jay Allen

ChrisB

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JAMCAM:
<strong>Chris at Spped Demon, thanks for taking my entire post and try to pick it apart.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"></strong>

Sorry if it came across like I was just trying to pick it apart - I was just trying to make sure I hit each and every point. No flames intended!

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">In both cases, acceleration = ET. Power is something that sells parts.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

I agree that acceleration = ET - if you feel I don't please let me know what quote gave you that impression and I will clarify it.

As for power being something that sells parts - I am sure it does. But the reason it sells parts is because it also makes the vehicles go faster. We are not talking about peak hp - rather area under the rpm range as seen down the track, etc.

Power is DIRECTLY related to your ability to accelerate over a given distance/time, etc. Look at your moroso power calculator - it calculates power from a givne distance, weight, trapspeed - as your ET, acceleration, whatever increase so does the calculated power. The fact that they are related is simple physics, and not really debateable - unless you wish to discuss the validity of newtonian physics itself.

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> You MUST have a chassis dyno and I stepped on your toes. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

Nope, don't have one. I do believe they are excellent tools though.

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Warren Johnson who I respect carries a power speed calculator too. Now, he's NOT God, but if REAL racers, not theorist use them, give it a try. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

I am not disagreeing that the calculators do what they claim, I simply pointed out why the numbers do not always agree with a chassis dyno. It is the difference between instantaneous and average values, not some conspiracy/discrepancy on the part of chassis dyno's.

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> The single pattern cam thing. Look in 95% of the cam books. They are mostly single pattern or very small spread cams. because the AVERAGE guy does not know better.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

How many books are written on the LS1? Cam timing for one engine doesn't really tell you much about for a completely different motor - especially a relatively clean sheet design like the LS1.



</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
Proof, take the exhaust off any LS1, why does it go faster?
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

Less backpressure. You will probably see the same thing on even large split pattern cams. A split pattern will not reduce backpressure - it will let you get a little more flow out the exhaust side since you have more valve open time - but you are still working against a pressure differential.

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
Now, I do not need my post sent back picked apart. If you'd like, I'd LOVE, I MEAN LOVE to talk back and forth about this junk. Please, either call me, or e-mail me your number and I will call you anytime.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

I will send you an email if you want also - but I think this is a good discussion and is also worth continuing here! Again, not trying to flame you or anything like that - this is just the easiest way for me to make sure I hit all the relevant points.

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
And no sir, power under the curve does not = ET.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">

How does it not? What would you submit equals ET - acceleration? What if I told you I can prove that area under the curve = acceleration?

Chris