Reverse torquer cam (the other side of the coin)
04-20-2009, 03:07 PM
#241
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no offense, but nearly everyone i have asked about reverse split cams says they dont work as well as a standard cam would. I honestly cant comment either way, as i dont know how to design cams, dont understand what an engine needs, etc. I wish i did.
I would love to see some back to back testing of a 2 cams, a reverse split and a traditional cam, both designed specifically for the setup.
I would love to see some back to back testing of a 2 cams, a reverse split and a traditional cam, both designed specifically for the setup.
04-20-2009, 03:48 PM
#242
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Thread Starter
Each will have their "niche" and the combos will be different.
Part of the argument you just mentionned (I've heard it a few times), was "Reverse fall flat on their face quickly and do not carry upper rpm power", well that has now been disproved. (it is in the valve events)
This thread is NOT about one is better than the other, this thread is to show, that thinking outside the box is good and myth can be just that "myth".
Part of the argument you just mentionned (I've heard it a few times), was "Reverse fall flat on their face quickly and do not carry upper rpm power", well that has now been disproved. (it is in the valve events)
This thread is NOT about one is better than the other, this thread is to show, that thinking outside the box is good and myth can be just that "myth".
05-15-2009, 11:06 AM
#243
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4.8T brings up a good point that wasn't addressed. 
Trucks in general have a pretty crappy intake, even the higher flowing L92 truck intakes aren't all that spectacular. They are also an expensive PITA to change over to Fast/LS6 style intakes because of the way our accessories are, fuel rails don't fit, harness mods, etc. All that coupled with the weight of a truck seems to point toward a reverse split being a good choice...
Trucks in general have a pretty crappy intake, even the higher flowing L92 truck intakes aren't all that spectacular. They are also an expensive PITA to change over to Fast/LS6 style intakes because of the way our accessories are, fuel rails don't fit, harness mods, etc. All that coupled with the weight of a truck seems to point toward a reverse split being a good choice...
ok, i have a good one. how about a 383 stroker with stock 317's and truck intake. long tubes no cats. all in a heavy *** AWD tahoe. 3.73's and 30.5" tall tires. 4l60e with a TT3000. i had a cam spec'd but that was with plans to go with a better intake and heads. but the way its looking i'm never going to get those. i'm lucky to be getting to build the 383 in the first place. the cam spec'd was a 228/232 639/643 110+2 with the intention of better heads and 90/90 set up or such. i have a idea. but i'm sure i'm way off but here it goes: 230/228 612/588 110 maybe with a +1 or so
here it is with 110 +/- 0
ivo 5
ivc 45
evo 44
evc 4
ecl 110
overlap9
i can mil the heads to raise the compression. thats no problem.
here it is with 110 +/- 0
ivo 5
ivc 45
evo 44
evc 4
ecl 110
overlap9
i can mil the heads to raise the compression. thats no problem.
05-15-2009, 11:43 AM
#244
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Thread Starter
I do not have experience with "big uglies", but from what I've seen those intakes do not like high reving and are designed to make maximum trq.
From tests I have seen, going past 6300 rpm in those is futile. So in theory (again I have never tested) a RS cam with the right VEs for powerband in mind should work well untill those rpms.
As for the specs given by 4.8T, my answer would be no. I would then be looking at an IVC of 40 or 41* max
something like this:
224/222 .609/.581 109 LSA
0.050
224/220
109>LSA
109>ICL
3>IVO
41>IVC
40>Evo
2>EVC
109>ECL
5*overlap
From tests I have seen, going past 6300 rpm in those is futile. So in theory (again I have never tested) a RS cam with the right VEs for powerband in mind should work well untill those rpms.
As for the specs given by 4.8T, my answer would be no. I would then be looking at an IVC of 40 or 41* max
something like this:
224/222 .609/.581 109 LSA
0.050
224/220
109>LSA
109>ICL
3>IVO
41>IVC
40>Evo
2>EVC
109>ECL
5*overlap
Last edited by PREDATOR-Z; 05-24-2009 at 05:39 AM.
05-24-2009, 05:48 AM
#246
TECH Senior Member
Thread Starter
It doesn't really, it is a matter of choosing proper valve events for said application
I run a 224/222 117 LSA in my 370, but I am running 12:1 Compression so instead of being a 4K+ cam the compression compensates down low. 463rwhp/424rwtq
I run a 224/222 117 LSA in my 370, but I am running 12:1 Compression so instead of being a 4K+ cam the compression compensates down low. 463rwhp/424rwtq
05-27-2009, 10:26 PM
#247
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hey predator i got a cam with my car its a 224-221 581-566 @113 lsa. Right now the car has a fast 78 a dual dual cat back and im probably gonna put headers on it this week. What do you think I could expect out of this cam and do you think itd be possible to hit 11's with it? It seems kinda small to me but I'm new to this stuff.
05-28-2009, 06:58 PM
#250
TECH Senior Member
Thread Starter
You can shoot pretty much any cam up to 100. Might see less efficiency from 100>150 and after that it is better to add a bit of exhaust duration. I wouldn't shoot more than 100>125 because after that you start contaminating the incoming charge.
05-28-2009, 07:14 PM
#251
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cool man, hmm this almost makes me want to try something like this, my current cam (in sig) doesnt have much low end but the stall helps, i feel all power after 5000, a 4400 would do wonders.
06-06-2009, 09:40 AM
#253
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I do not have experience with "big uglies", but from what I've seen those intakes do not like high reving and are designed to make maximum trq.
From tests I have seen, going past 6300 rpm in those is futile. So in theory (again I have never tested) a RS cam with the right VEs for powerband in mind should work well untill those rpms.
As for the specs given by 4.8T, my answer would be no. I would then be looking at an IVC of 40 or 41* max
something like this:
224/222 .609/.581 109 LSA
0.050
224/220
109>LSA
109>ICL
3>IVO
41>IVC
40>Evo
2>EVC
109>ECL
5*overlap
From tests I have seen, going past 6300 rpm in those is futile. So in theory (again I have never tested) a RS cam with the right VEs for powerband in mind should work well untill those rpms.
As for the specs given by 4.8T, my answer would be no. I would then be looking at an IVC of 40 or 41* max
something like this:
224/222 .609/.581 109 LSA
0.050
224/220
109>LSA
109>ICL
3>IVO
41>IVC
40>Evo
2>EVC
109>ECL
5*overlap
now what if this was a stock compression 6.0l with the new edelbrock xt intake? still in the heavy truck with long tubes and full exhaust.
06-20-2009, 02:46 PM
#254
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this thread is long and old, so i havent read all of the posts, but i just thought id give my 2 cents.
all of loyd elliots LS cams are either the same on int. and exh., or they are a reverse split. so there must be something to it.....
this is right off his site...
218/214 .578/.578 114 LSA - "sleeper cam" with smooth idle and TONS of TQ at every
RPM from idle to 6000 RPM. This cam is a "torque monster".
222/222 .600/.600 112 LSA - mild idle, can be used with stock gears and no stall.
Good all around power. 1500-6200 RPM
226/226 .600/.600 112 LSA - aggressive idle, works well with 2800 stall and
3.42/3.73 gears. 1800-6500 RPM.
230/226 .600/.600 113 LSA - choppy idle, works well with 3200-3600 stall and
3.73/4.11 gears. 2100-6800 RPM.
234/230 .600/.600 113 LSA - great cam for stroker engines wanting strong mid range and top end power. Works best with 3600-4400 stall and 3.73/4.11 gears. 2500-6800 RPM.
if anyone is running this sleeper cam with tons of torque, id like to hear a sound clip!!!! or any of these cams for that matter....
all of loyd elliots LS cams are either the same on int. and exh., or they are a reverse split. so there must be something to it.....
this is right off his site...
218/214 .578/.578 114 LSA - "sleeper cam" with smooth idle and TONS of TQ at every
RPM from idle to 6000 RPM. This cam is a "torque monster".
222/222 .600/.600 112 LSA - mild idle, can be used with stock gears and no stall.
Good all around power. 1500-6200 RPM
226/226 .600/.600 112 LSA - aggressive idle, works well with 2800 stall and
3.42/3.73 gears. 1800-6500 RPM.
230/226 .600/.600 113 LSA - choppy idle, works well with 3200-3600 stall and
3.73/4.11 gears. 2100-6800 RPM.
234/230 .600/.600 113 LSA - great cam for stroker engines wanting strong mid range and top end power. Works best with 3600-4400 stall and 3.73/4.11 gears. 2500-6800 RPM.
if anyone is running this sleeper cam with tons of torque, id like to hear a sound clip!!!! or any of these cams for that matter....
09-06-2009, 02:48 PM
#255
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Airaid modular intake tube with K&N drop in
Ported throttle body
Electric fans
Pacesetter headers with 3 inch true duals with factory cats and x-pipe muffler
Cam stock with 317 heads that I plan on milling 0.040
Comments?
09-22-2009, 08:08 PM
#256
I haven't read this whole thread because it's been on forever, but that's a good thing. However, if it hasn't been brought up yet, wouldn't a reverse split cam work well on a head like the L92 because of the drastic sizes 2.16int / 1.59exh by keeping the tiny exhaust open longer?
10-04-2009, 11:44 AM
#257
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I try to use reverse splits whenever possible (pretty much anything but a sheetmetal intake).
Even the 222/222 cam on my site is an older grind and I now use a 223/218 .601/.558 cam in its place.
More duration (intake or exhaust) doesn't mean more power. If the valve is open, you are allowing air to enter/exit the cylinder and that is a good thing to an extent. You also have to worry about these things the valve being opn too long or opening/closing at the wrong time . . .
IVO- earleir you open the valve, the higher the lift point when the piston starts sucking on the port (good thing) but you have to watch the IVO/EVC and amount of overlap so you do not contaminate the mixture of next intake strtoke.
IVC- earlier you close the intake valve, the more cylinder pressure you trap and the later you close the intake valve, the less cylinder pressure you trap but a later IVC also allows a few extre degrees for cylinder filling and can make a lil more top end power.
EVO- earlier you open the exhaust valve, the sooner you stop pushing on the piston (blow down). This can hurt TQ at low RPM, mid range and even top end. If using enough nitrous or have enough intake flow (sheet metal intake, etc), you can see some HP at high RPM by an earleir EVO. Most people lose alot of TQ with too early of an EVO.
EVC- the later you close the ex valve (tighter LSA, larger ex duration lobe), the higher lift the valve is at when the piston nears TDC so you can get more air out of the cylinder but you have to worry about where the air is going and make sure it is going out the exhaust instead of up the intake port (reversion) during overlap. The earleir you close the exhaust valve, the less reversion you have to contend with.
Most LS1's will end up making more power by having a smaller ex lobe since you eliminate some of the problems with overlap by using an earlier EVC and not blowing down the cylinder by using a later EVO.
The lobes that I use are the Ultradyne and Bullet lobes. Lobes that have the same .006, .050 and .200 duration are not all the same. The Ultradyne/Bullet lobes I have are severely assymatrical and are MUCH fatter on the opening side. You can only close the valve at a certain rate and remain stable at high RPM so you are kinda fixed on how fast you can close the valve and the closing ramp speed of the lobe but you can open the valve alot more aggressively and put the valve at a higher lift sooner so the engine "thinks" that you have the intake on a lower centerline (starts filling intake sooner) but you knock off about 3 degrees of negative stuff during IVO (reversion) and EVO (blow down cylinder) so you make more power.
there are always trade offs but I believe if using a LS1, LS6 or fast 90 intake and spinning 6800 RPM or less, a reverse split will be the better choice.
Anyone with Desk top Dyno, Engine Analyzer Pro, etc might not see all of these benfits and even though Dynomation5 is still a program, it has alot more inputs and things to measure (cross sections, runner lengths, venturi diameters, etc) that will have a more realistic grasp on the pulses going through the engine (intake and exhaust). It si still a program, it is just a lil closer to "real life".
Lloyd
Even the 222/222 cam on my site is an older grind and I now use a 223/218 .601/.558 cam in its place.
More duration (intake or exhaust) doesn't mean more power. If the valve is open, you are allowing air to enter/exit the cylinder and that is a good thing to an extent. You also have to worry about these things the valve being opn too long or opening/closing at the wrong time . . .
IVO- earleir you open the valve, the higher the lift point when the piston starts sucking on the port (good thing) but you have to watch the IVO/EVC and amount of overlap so you do not contaminate the mixture of next intake strtoke.
IVC- earlier you close the intake valve, the more cylinder pressure you trap and the later you close the intake valve, the less cylinder pressure you trap but a later IVC also allows a few extre degrees for cylinder filling and can make a lil more top end power.
EVO- earlier you open the exhaust valve, the sooner you stop pushing on the piston (blow down). This can hurt TQ at low RPM, mid range and even top end. If using enough nitrous or have enough intake flow (sheet metal intake, etc), you can see some HP at high RPM by an earleir EVO. Most people lose alot of TQ with too early of an EVO.
EVC- the later you close the ex valve (tighter LSA, larger ex duration lobe), the higher lift the valve is at when the piston nears TDC so you can get more air out of the cylinder but you have to worry about where the air is going and make sure it is going out the exhaust instead of up the intake port (reversion) during overlap. The earleir you close the exhaust valve, the less reversion you have to contend with.
Most LS1's will end up making more power by having a smaller ex lobe since you eliminate some of the problems with overlap by using an earlier EVC and not blowing down the cylinder by using a later EVO.
The lobes that I use are the Ultradyne and Bullet lobes. Lobes that have the same .006, .050 and .200 duration are not all the same. The Ultradyne/Bullet lobes I have are severely assymatrical and are MUCH fatter on the opening side. You can only close the valve at a certain rate and remain stable at high RPM so you are kinda fixed on how fast you can close the valve and the closing ramp speed of the lobe but you can open the valve alot more aggressively and put the valve at a higher lift sooner so the engine "thinks" that you have the intake on a lower centerline (starts filling intake sooner) but you knock off about 3 degrees of negative stuff during IVO (reversion) and EVO (blow down cylinder) so you make more power.
there are always trade offs but I believe if using a LS1, LS6 or fast 90 intake and spinning 6800 RPM or less, a reverse split will be the better choice.
Anyone with Desk top Dyno, Engine Analyzer Pro, etc might not see all of these benfits and even though Dynomation5 is still a program, it has alot more inputs and things to measure (cross sections, runner lengths, venturi diameters, etc) that will have a more realistic grasp on the pulses going through the engine (intake and exhaust). It si still a program, it is just a lil closer to "real life".
Lloyd
Last edited by NightTrain66; 11-10-2009 at 08:42 AM.
10-07-2009, 12:32 PM
#259
[QUOTE=NightTrain66;12315721]I try to use reverse splits whenever possible (pretty much anything but a sheetmetal intake).
Even the 222/222 cam on my site is an older grind and I now use a 223/218 .601/.558 cam in its place.
Amazingly, I have used reverse splits in L92 applications for people wanting to fatten the TQ curve over there cam set up. Even 408-427 strokers with 236/242 .6xx/.6xx 110-113 LSA cams see a HUGE increase in low/mid range TQ by using a 234/230 .600/.600 112 LSA cam and still make the same or more MORE HP at 6500 RPM also.
i was curious how a reverse split would work on bigger cubes. i just did some old searches and back in the day MTI put there X1 in a 422 and it made
48x rwhp and 509 torque!!!! thats with an LS6 intake and LS6 heads.. for a small cam to put that much torque is insane. imagine the drivability of that cam. very civil, and easy on the valvetrain. also nine ball i believe pointed out that if it was a bigger cam and more traditional split the numbers probably would be opposite.. 500+hp and 480 torque. goes to show you that these "band aid" "retarded" cams can perform!!
Even the 222/222 cam on my site is an older grind and I now use a 223/218 .601/.558 cam in its place.
Amazingly, I have used reverse splits in L92 applications for people wanting to fatten the TQ curve over there cam set up. Even 408-427 strokers with 236/242 .6xx/.6xx 110-113 LSA cams see a HUGE increase in low/mid range TQ by using a 234/230 .600/.600 112 LSA cam and still make the same or more MORE HP at 6500 RPM also.
i was curious how a reverse split would work on bigger cubes. i just did some old searches and back in the day MTI put there X1 in a 422 and it made
48x rwhp and 509 torque!!!! thats with an LS6 intake and LS6 heads.. for a small cam to put that much torque is insane. imagine the drivability of that cam. very civil, and easy on the valvetrain. also nine ball i believe pointed out that if it was a bigger cam and more traditional split the numbers probably would be opposite.. 500+hp and 480 torque. goes to show you that these "band aid" "retarded" cams can perform!!
10-07-2009, 02:58 PM
#260
I try to use reverse splits whenever possible (pretty much anything but a sheetmetal intake).
Even the 222/222 cam on my site is an older grind and I now use a 223/218 .601/.558 cam in its place.
Amazingly, I have used reverse splits in L92 applications for people wanting to fatten the TQ curve over there cam set up. Even 408-427 strokers with 236/242 .6xx/.6xx 110-113 LSA cams see a HUGE increase in low/mid range TQ by using a 234/230 .600/.600 112 LSA cam and still make the same or more MORE HP at 6500 RPM also.
More duration (intake or exhaust) doesn't mean more power. If the valve is open, you are allowing air to enter/exit the cylinder and that is a good thing to an extent. You also have to worry about these things the valve being opn too long or opening/closing at the wrong time . . .
IVO- earleir you open the valve, the higher the lift point when the piston starts sucking on the port (good thing) but you have to watch the IVO/EVC and amount of overlap so you do not contaminate the mixture of next intake strtoke.
IVC- earlier you close the intake valve, the more cylinder pressure you trap and the later you close the intake valve, the less cylinder pressure you trap but a later IVC also allows a few extre degrees for cylinder filling and can make a lil more top end power.
EVO- earlier you open the exhaust valve, the sooner you stop pushing on the piston (blow down). This can hurt TQ at low RPM, mid range and even top end. If using enough nitrous or have enough intake flow (sheet metal intake, etc), you can see some HP at high RPM by an earleir EVO. Most people lose alot of TQ with too early of an EVO.
EVC- the later you close the ex valve (tighter LSA, larger ex duration lobe), the higher lift the valve is at when the piston nears TDC so you can get more air out of the cylinder but you have to worry about where the air is going and make sure it is going out the exhaust instead of up the intake port (reversion) during overlap. The earleir you close the exhaust valve, the less reversion you have to contend with.
Most LS1's will end up making more power by having a smaller ex lobe since you eliminate some of the problems with overlap by using an earlier EVC and not blowing down the cylinder by using a later EVO.
The lobes that I use are the Ultradyne and Bullet lobes. Lobes that have the same .006, .050 and .200 duration are not all the same. The Ultradyne/Bullet lobes I have are severely assymatrical and are MUCH fatter on the opening side. You can only close the valve at a certain rate and remain stable at high RPM so you are kinda fixed on how fast you can close the valve and the closing ramp speed of the lobe but you can open the valve alot more aggressively and put the valve at a higher lift sooner so the engine "thinks" that you have the intake on a lower centerline (starts filling intake sooner) but you knock off about 3 degrees of negative stuff during IVO (reversion) and EVO (blow down cylinder) so you make more power.
there are always trade offs but I believe if using a LS1, LS6 or fast 90 intake and spinning 6800 RPM or less, a reverse split will be the better choice.
Anyone with Desk top Dyno, Engine Analyzer Pro, etc might not see all of these benfits and even though Dynomation5 is still a program, it has alot more inputs and things to measure (cross sections, runner lengths, venturi diameters, etc) that will have a more realistic grasp on the pulses going through the engine (intake and exhaust). It si still a program, it is just a lil closer to "real life".
Lloyd
Even the 222/222 cam on my site is an older grind and I now use a 223/218 .601/.558 cam in its place.
Amazingly, I have used reverse splits in L92 applications for people wanting to fatten the TQ curve over there cam set up. Even 408-427 strokers with 236/242 .6xx/.6xx 110-113 LSA cams see a HUGE increase in low/mid range TQ by using a 234/230 .600/.600 112 LSA cam and still make the same or more MORE HP at 6500 RPM also.
More duration (intake or exhaust) doesn't mean more power. If the valve is open, you are allowing air to enter/exit the cylinder and that is a good thing to an extent. You also have to worry about these things the valve being opn too long or opening/closing at the wrong time . . .
IVO- earleir you open the valve, the higher the lift point when the piston starts sucking on the port (good thing) but you have to watch the IVO/EVC and amount of overlap so you do not contaminate the mixture of next intake strtoke.
IVC- earlier you close the intake valve, the more cylinder pressure you trap and the later you close the intake valve, the less cylinder pressure you trap but a later IVC also allows a few extre degrees for cylinder filling and can make a lil more top end power.
EVO- earlier you open the exhaust valve, the sooner you stop pushing on the piston (blow down). This can hurt TQ at low RPM, mid range and even top end. If using enough nitrous or have enough intake flow (sheet metal intake, etc), you can see some HP at high RPM by an earleir EVO. Most people lose alot of TQ with too early of an EVO.
EVC- the later you close the ex valve (tighter LSA, larger ex duration lobe), the higher lift the valve is at when the piston nears TDC so you can get more air out of the cylinder but you have to worry about where the air is going and make sure it is going out the exhaust instead of up the intake port (reversion) during overlap. The earleir you close the exhaust valve, the less reversion you have to contend with.
Most LS1's will end up making more power by having a smaller ex lobe since you eliminate some of the problems with overlap by using an earlier EVC and not blowing down the cylinder by using a later EVO.
The lobes that I use are the Ultradyne and Bullet lobes. Lobes that have the same .006, .050 and .200 duration are not all the same. The Ultradyne/Bullet lobes I have are severely assymatrical and are MUCH fatter on the opening side. You can only close the valve at a certain rate and remain stable at high RPM so you are kinda fixed on how fast you can close the valve and the closing ramp speed of the lobe but you can open the valve alot more aggressively and put the valve at a higher lift sooner so the engine "thinks" that you have the intake on a lower centerline (starts filling intake sooner) but you knock off about 3 degrees of negative stuff during IVO (reversion) and EVO (blow down cylinder) so you make more power.
there are always trade offs but I believe if using a LS1, LS6 or fast 90 intake and spinning 6800 RPM or less, a reverse split will be the better choice.
Anyone with Desk top Dyno, Engine Analyzer Pro, etc might not see all of these benfits and even though Dynomation5 is still a program, it has alot more inputs and things to measure (cross sections, runner lengths, venturi diameters, etc) that will have a more realistic grasp on the pulses going through the engine (intake and exhaust). It si still a program, it is just a lil closer to "real life".
Lloyd