Cam split pattern logic and results?
03-21-2004, 08:59 PM
#1
Cam split pattern logic and results? In my schooling (60's cars) we used a higher lift/longer duration lobe on the intake side if the head flow was weak compared to the exhaust side, and visa versa.
So a 230/226, .591/.569 split to me suggests that the ntake side of the head needs compensation by trying to allow more time/amount of valve opening.
I see LS1 cams split both ways.
WHY?
What is the theory?
My own purpose is choosing between a TR224/224, .563/.563 112 cam or geting more power with bigger cam without p/v issues. also mid/low 11's with pump gas and daily diven 2000 Formula.
I see good numbers in the sigs of guys with straight pattern and higher intake lobe split cams. Would, say, a F1 230/226, .591/.569 112 cam give me that extra punch? Is this cam making up for lower intake flow through the motor?
Should I stick with a straight pattern?
My heads are 5.7 Stage2 flowing the exact numbers as TEA heads by the graph. Milled .035 wih Rev dual springs. LS6 intake and longtubes. 4000 stall and 3.73
Will that F1 grind pull enough over the TR224 to get me mid 11's?
I'll take actual results and suggestions for my cam pick but really want to know what's up with the reverse and straight split patterns to choose from. It's confusing right now!
So a 230/226, .591/.569 split to me suggests that the ntake side of the head needs compensation by trying to allow more time/amount of valve opening.
I see LS1 cams split both ways.
WHY?
What is the theory?
My own purpose is choosing between a TR224/224, .563/.563 112 cam or geting more power with bigger cam without p/v issues. also mid/low 11's with pump gas and daily diven 2000 Formula.
I see good numbers in the sigs of guys with straight pattern and higher intake lobe split cams. Would, say, a F1 230/226, .591/.569 112 cam give me that extra punch? Is this cam making up for lower intake flow through the motor?
Should I stick with a straight pattern?
My heads are 5.7 Stage2 flowing the exact numbers as TEA heads by the graph. Milled .035 wih Rev dual springs. LS6 intake and longtubes. 4000 stall and 3.73
Will that F1 grind pull enough over the TR224 to get me mid 11's?
I'll take actual results and suggestions for my cam pick but really want to know what's up with the reverse and straight split patterns to choose from. It's confusing right now!
03-22-2004, 01:17 AM
#2
OK the way I understand it, LS1's seem to like all types of cams, but in the lower lift range with stock exhaust, you do better with a traditional split. For mid sized cams like the TR224 used with headers, equal duration is best because the LS1 head design is very good and flows the same, intake and exhaust. For very large cams, the intake manifold becomes the bottle neck and you can get more power with a reverse split, but this is at the cost of low rpm torque. I have the TR224 and feel it's the best street cam out there, but something in the 230 range is better for racing if you don't have to pass emissions.
03-22-2004, 01:21 AM
#3
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I posted a similar question on another board and din not get much of a response. My question was how much of a split can you go? What are the positive and negative sides of single vs dual pattern cams?
I have a 2000 Camaro. The mods are air box lid, smooth bellows, K&N air filter, Gmaf, 4:11 gears and a 220/226 564 569 113+4 cam. I know the exhaust is restricted, does the increase in duration actually have much of a positive affect? What is the biggest cam you can run on the streets and maintain enough low end for daily driving? Is comp cams xe-r lobes practical for street use?
And last but not least, what is the best least expensive header assembly to buy? With headers do you need high flow cats also?
I have a 2000 Camaro. The mods are air box lid, smooth bellows, K&N air filter, Gmaf, 4:11 gears and a 220/226 564 569 113+4 cam. I know the exhaust is restricted, does the increase in duration actually have much of a positive affect? What is the biggest cam you can run on the streets and maintain enough low end for daily driving? Is comp cams xe-r lobes practical for street use?
And last but not least, what is the best least expensive header assembly to buy? With headers do you need high flow cats also?
03-22-2004, 09:00 AM
#5
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cams like my 224/226 worth especially well with nitrous 
gotta get that exhaust flow out. I dont think i'll be needing heads/nitrous to push into the 11's though.
gotta get that exhaust flow out. I dont think i'll be needing heads/nitrous to push into the 11's though.
03-22-2004, 09:30 AM
#6
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You are right in your thinking. Splits are for "crutching" either an intake or an exhaust side that is less efficent than the other. Look at the intake to exhaust efficency with the intake in place, and you can see that its around 80% for many of the heads out there. The stock intake has about a 15inch runner length, much like an old dual plane, so you have to cam accordingly.
Your cam selection should be based upon your combo.
Your cam selection should be based upon your combo.
03-22-2004, 09:45 AM
#7
Originally Posted by TA27
I posted a similar question on another board and din not get much of a response. My question was how much of a split can you go? What are the positive and negative sides of single vs dual pattern cams?
I have a 2000 Camaro. The mods are air box lid, smooth bellows, K&N air filter, Gmaf, 4:11 gears and a 220/226 564 569 113+4 cam. I know the exhaust is restricted, does the increase in duration actually have much of a positive affect? What is the biggest cam you can run on the streets and maintain enough low end for daily driving? Is comp cams xe-r lobes practical for street use?
And last but not least, what is the best least expensive header assembly to buy? With headers do you need high flow cats also?
I have a 2000 Camaro. The mods are air box lid, smooth bellows, K&N air filter, Gmaf, 4:11 gears and a 220/226 564 569 113+4 cam. I know the exhaust is restricted, does the increase in duration actually have much of a positive affect? What is the biggest cam you can run on the streets and maintain enough low end for daily driving? Is comp cams xe-r lobes practical for street use?
And last but not least, what is the best least expensive header assembly to buy? With headers do you need high flow cats also?
TA27 - that's a bunch of questions you have buried in this post. You might want to break each question down in a seperate post and call some cam manufacturers - that's what I'm going to do now. I don't know enough about these motors to piick my lobes and lca myself yet.
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03-22-2004, 09:52 AM
#8
Originally Posted by J-Rod
You are right in your thinking. Splits are for "crutching" either an intake or an exhaust side that is less efficent than the other. Look at the intake to exhaust efficency with the intake in place, and you can see that its around 80% for many of the heads out there. The stock intake has about a 15inch runner length, much like an old dual plane, so you have to cam accordingly.
Your cam selection should be based upon your combo.
Your cam selection should be based upon your combo.
Glad that 26 years learning those old cars wasn't totally useless toward building one of these!
My heads flow 296 at .600 lift and decent numbers up the scale. The exhaust is just around 80 % of those numbers as you said. That is the same ratio of flow we shot for with old motors and used straight pattern cams most of the time. But as mentioned above, if the intake becomes a bottle neck than a larger lobe to compensate makes sense, to a degree. I bought the good Canadian LS6 intake that supposedly flows with the aftermarkets so with longube headers I bet a straight patern cam would be fine for a n/a street car.
03-22-2004, 09:56 AM
#9
Originally Posted by Cal
OK the way I understand it, LS1's seem to like all types of cams, but in the lower lift range with stock exhaust, you do better with a traditional split. For mid sized cams like the TR224 used with headers, equal duration is best because the LS1 head design is very good and flows the same, intake and exhaust. For very large cams, the intake manifold becomes the bottle neck and you can get more power with a reverse split, but this is at the cost of low rpm torque. I have the TR224 and feel it's the best street cam out there, but something in the 230 range is better for racing if you don't have to pass emissions.
Did you ever get track or dyno numbers with your car and the TR224? I have almost the exact same set up and you might help me decide what to choose for a cam. Bigger is NOT always better
03-22-2004, 10:21 AM
#10
It seems like there are a ton of cams that make power in the LS1.
The H/C combo's that have the best results right now all have cams in the with triditional split patterns. The 231/237 is one example. There are a ton of cars using this cam. The G5X2 and G5X3 are 2 more great examples of really fast/ high dyno cars. Cartex fastest cars is another good example. MTI's bigger cam for stcok cubic inch is a 232/236 (somewhere in that area) And we all know what the T-Rex cam is....
Seems like the majority of the fast cars all run this stlye cam. It is great for exhaust scaveling. Also the Nitrous really does well with these cams.
Jason from thunder racing told me on the phone a few weeks ago he would be installing some reverse split cams very soon to see what results can be achived. He is one guy you should call. I talked to Jay @ AS and he defentially said a regular split would be best for his heads.
The H/C combo's that have the best results right now all have cams in the with triditional split patterns. The 231/237 is one example. There are a ton of cars using this cam. The G5X2 and G5X3 are 2 more great examples of really fast/ high dyno cars. Cartex fastest cars is another good example. MTI's bigger cam for stcok cubic inch is a 232/236 (somewhere in that area) And we all know what the T-Rex cam is....
Seems like the majority of the fast cars all run this stlye cam. It is great for exhaust scaveling. Also the Nitrous really does well with these cams.
Jason from thunder racing told me on the phone a few weeks ago he would be installing some reverse split cams very soon to see what results can be achived. He is one guy you should call. I talked to Jay @ AS and he defentially said a regular split would be best for his heads.
03-22-2004, 10:44 AM
#11
I just talked to Thunder, Comp and Speed Tek.
All confirmed the larger intake lobe is to componsate weak intake manifold flow. Larger exhaust lobe is to scavange for nitrous mostly.
My personal set up is limited because of heads milled .035. All agreed that p/v issues will arise above the TR224 / .563 lift range. Also to squeeze up to around .585 liift won't gain enough power to justify the risk of breaking something. Last is my goal is mid 11's with full weight and lots of guys have seen the TR224 get there with the right bolt ons and nice flowing heads.
Good lessons learned without breaking any parts or swapping 5 cams
thanks all !
All confirmed the larger intake lobe is to componsate weak intake manifold flow. Larger exhaust lobe is to scavange for nitrous mostly.
My personal set up is limited because of heads milled .035. All agreed that p/v issues will arise above the TR224 / .563 lift range. Also to squeeze up to around .585 liift won't gain enough power to justify the risk of breaking something. Last is my goal is mid 11's with full weight and lots of guys have seen the TR224 get there with the right bolt ons and nice flowing heads.
Good lessons learned without breaking any parts or swapping 5 cams
thanks all !
03-22-2004, 10:58 AM
#12
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yeah thats the best thing to do, lay out your mods and verter and let them choose. They will not steer you awry. The stall has big play in the cam choice. You want to nail alot of torque of the hole (why we got the stall) and have a cam that has enough rpm in it for the shift extension.
combination motorsports picked mine. I'm quite please with it. Although the pwhp is low, it did produce the #'s i expected out of the car and my skill level at the strip..
combination motorsports picked mine. I'm quite please with it. Although the pwhp is low, it did produce the #'s i expected out of the car and my skill level at the strip..
03-22-2004, 11:59 AM
#13
Just to let you know I have seen a 227 cam installed in a car with heads milled .030
It was a 227/230 cam and made nice power.
Mid 11's shouldn't be too hard, just pay attention to detail and make sure you have a great combo of power/suspension/tires/tune/converter/driver.
It was a 227/230 cam and made nice power.
Mid 11's shouldn't be too hard, just pay attention to detail and make sure you have a great combo of power/suspension/tires/tune/converter/driver.
03-22-2004, 01:35 PM
#14
6600 rpm clutch dump of death Administrator
The Aussies are doing single pattern or slighly reverse split cams. They tighten up the LSAs to use better valve events like a
232/232 108LSA 108ICL
242/242 106LSA 105ICL
273/273 104LSA 103ICL
232/232 108LSA 108ICL
242/242 106LSA 105ICL
273/273 104LSA 103ICL
03-24-2004, 12:16 AM
#15
Originally Posted by chief455
That makes good sense and I didn't now the intake manifold was the weak link in the flow chain
Did you ever get track or dyno numbers with your car and the TR224? I have almost the exact same set up and you might help me decide what to choose for a cam. Bigger is NOT always better
Did you ever get track or dyno numbers with your car and the TR224? I have almost the exact same set up and you might help me decide what to choose for a cam. Bigger is NOT always better
03-25-2004, 10:21 AM
#17
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Originally Posted by J-Rod
The Aussies are doing single pattern or slighly reverse split cams. They tighten up the LSAs to use better valve events like a
232/232 108LSA 108ICL
242/242 106LSA 105ICL
273/273 104LSA 103ICL
232/232 108LSA 108ICL
242/242 106LSA 105ICL
273/273 104LSA 103ICL
03-25-2004, 10:53 AM
#18
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Originally Posted by myZ
You got a link to one of those downunder sites?....My understanding is a 110 will have a choppy idle...108-104 holy crap, and those durations lookpretty long as well, i love it. I'm assuming these are all track cams then right? I'd like to know more about these!
Try this link.
http://www.ls1.com.au/forum/index.php
LoL