Cam for L92 Heads: Lessons Learned
So who is the man when it comes to specing out an l92 setup cam?
I messaged pat g and even mentioned I would pay for his services... Never got a reply.
Quick run down... L76 (aluminum 6.0) stock l92 heads, have jot decided if I will be porting milling them at this time, ported ls3 intake... Then 1 7/8 headers, ptc 4000, etc etc..
I want it more geared towards the track/weekend warrior type.. Not more of a daily that I see in most g8/'10 camaro setups that seem to be more geared towards daily driving duties.
I messaged pat g and even mentioned I would pay for his services... Never got a reply.
Quick run down... L76 (aluminum 6.0) stock l92 heads, have jot decided if I will be porting milling them at this time, ported ls3 intake... Then 1 7/8 headers, ptc 4000, etc etc..
I want it more geared towards the track/weekend warrior type.. Not more of a daily that I see in most g8/'10 camaro setups that seem to be more geared towards daily driving duties.
Waiting to get my L92/LS3 heads and intake back from being ported & milled by the local portworks shop out of Red Oak, Tx. He also recommended a custom grind comp 227/239 .614/.624 114 with the LSL lobes. Said the LSL lobes have a high lift, but a ramp speed that was much easier on springs etc.. I will post flow numbers on the heads as soon as i have them
LQ9 STOCK bottom 20k
L92 heads ported, milled .020 with Manley springs
LS3 intake ported with 90mm Edelbrock TB
Longtube headers 1 3/4' with true duals x piped and dumped
Not sure where the tune will come from ?
Car is a 99 SS M6
LQ9 STOCK bottom 20k
L92 heads ported, milled .020 with Manley springs
LS3 intake ported with 90mm Edelbrock TB
Longtube headers 1 3/4' with true duals x piped and dumped
Not sure where the tune will come from ?
Car is a 99 SS M6
Teching In
Joined: Oct 2011
Posts: 1
Likes: 0
From: edmonton alberta
need help building 6.0 truck block have l92 heads,fast 102 intake,injectors,and tb
going into 91 camaro with t56 and 373 rear gears need advise/help getting pistons and cam.tried to get diamond pistons waited 2 months the was told to wait longer i wasted enough time just want to start assmbly.any help would be greatly appreciated
going into 91 camaro with t56 and 373 rear gears need advise/help getting pistons and cam.tried to get diamond pistons waited 2 months the was told to wait longer i wasted enough time just want to start assmbly.any help would be greatly appreciated
6600 rpm clutch dump of death Administrator
Joined: Dec 2001
Posts: 4,983
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From: Texas
I've been playing with cams for my 404 L76 in Performance Trends Engine Analyzer Pro. My calculations all used the stock LS3 head flow numbers obtained by Richard at WCCH, with a stock intake manifold. Many many hours. Intake durations varying from 232 to 245 hardley changed the horsepower. I've settled on an intake duration of 238. What I did find interesting was the exhaust duration. All of comp cams LS3 cams have about 15 degrees more exhaust duration than intake. I will have an exhaust that flows as well as open headers and always thought that 15 degree split was a bit much. Originally I was sure that a 6 degree split would be ideal. But Analyzer Pro showed a loss of only 1-2 hp over 6000 rpm, and a strong gain of 13 ft lbs almost everywhere below 5000 rpm by reducing the split exhaust/crutch to only 2 degrees more than the intake at 0.050"!
I really didn't expect to see that since EVERYONE runs silly large splits on rectangle port motors.
The only other thing that I found interesting by messing with as many variables as I could was the change from swapping the stock intake manifold for tunnel ram style (new holley anyone?!). Over 6500 a tunnel ram picks up a huge 50 hp. But it doesn't come free, with a loss of up to 60 ft bls below 4000 rpm.
I really didn't expect to see that since EVERYONE runs silly large splits on rectangle port motors.
The only other thing that I found interesting by messing with as many variables as I could was the change from swapping the stock intake manifold for tunnel ram style (new holley anyone?!). Over 6500 a tunnel ram picks up a huge 50 hp. But it doesn't come free, with a loss of up to 60 ft bls below 4000 rpm.
I am not discouting what EA says, I just know that you sometimes really have to fiddle with the data to get what EA says to match the real numbers.
As for the gains with a tunnel ram, thats consistent with what most folks have seen. I'll use MTI as an example. When SW was working on breaking into the 9's with his 427, Jason had a short runner sheetmetal manifold built. It picked up 20 HP on SW's motor peak, but it lost 50 lb/ft tq across the board down low. So the tradeoff wasn't worth it.
But, the Holley has a fairly long runner, so again, you need to check the model against reality.
I've been playing with cams for my 404 L76 in Performance Trends Engine Analyzer Pro. My calculations all used the stock LS3 head flow numbers obtained by Richard at WCCH, with a stock intake manifold. Many many hours. Intake durations varying from 232 to 245 hardley changed the horsepower. I've settled on an intake duration of 238. What I did find interesting was the exhaust duration. All of comp cams LS3 cams have about 15 degrees more exhaust duration than intake. I will have an exhaust that flows as well as open headers and always thought that 15 degree split was a bit much. Originally I was sure that a 6 degree split would be ideal. But Analyzer Pro showed a loss of only 1-2 hp over 6000 rpm, and a strong gain of 13 ft lbs almost everywhere below 5000 rpm by reducing the split exhaust/crutch to only 2 degrees more than the intake at 0.050"!
I really didn't expect to see that since EVERYONE runs silly large splits on rectangle port motors.
The only other thing that I found interesting by messing with as many variables as I could was the change from swapping the stock intake manifold for tunnel ram style (new holley anyone?!). Over 6500 a tunnel ram picks up a huge 50 hp. But it doesn't come free, with a loss of upto 60 ft bls below 4000 rpm.
I really didn't expect to see that since EVERYONE runs silly large splits on rectangle port motors.
The only other thing that I found interesting by messing with as many variables as I could was the change from swapping the stock intake manifold for tunnel ram style (new holley anyone?!). Over 6500 a tunnel ram picks up a huge 50 hp. But it doesn't come free, with a loss of upto 60 ft bls below 4000 rpm.
TECH Addict
Joined: Sep 2010
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Hello hymey.
I just got a custom camshaft from Ed Curtis of Flowtech Induction.
I have l92 heads with cnc work and 11:5.1 compression as well as a ported fast 102mm manifold.
I have been through two camshafts with this head and I have not been happy with either.
229/242 .631 .631 114.5LSA
224/232 .580 .580 115LSA.
My car is auto and both drive like crap with not much torque anywhere in the rpm range except in a narrow area near the upper rpms.
The cam that Ed curtis designed for me is a 219/227 .625 .619 112LSA+4
He goes the timing events for what Im after (which is maximum torque throughout the range) are perfect and are actually perfectly suited for my combo. Maximum torque will hit at 2100-6200rpm so will be in the sweet spot of my 2500rpm stall converter.
This cam should be an absolute monster in my engine.
Can't wait to get it installed.
it's very similar to the one you have.
I just got a custom camshaft from Ed Curtis of Flowtech Induction.
I have l92 heads with cnc work and 11:5.1 compression as well as a ported fast 102mm manifold.
I have been through two camshafts with this head and I have not been happy with either.
229/242 .631 .631 114.5LSA
224/232 .580 .580 115LSA.
My car is auto and both drive like crap with not much torque anywhere in the rpm range except in a narrow area near the upper rpms.
The cam that Ed curtis designed for me is a 219/227 .625 .619 112LSA+4
He goes the timing events for what Im after (which is maximum torque throughout the range) are perfect and are actually perfectly suited for my combo. Maximum torque will hit at 2100-6200rpm so will be in the sweet spot of my 2500rpm stall converter.
This cam should be an absolute monster in my engine.
Can't wait to get it installed.
it's very similar to the one you have.
That's a great post. What pcm you using? LS1-B. Do you have a COS like efilives COS-3? That can be useful.
When tuning cammed L92 headed engines with an e38pcm, I find airflow adjustment is the only thing that dials out surging that occurs normally between 1200~1600rpm. It has an electronic TB(90mm). The e38 has a setting called max idle area. It shows up at 1.82 stock. This equates to 18.8% throttle opening. So if you are idling over the airflow correction may pull it back to 14% to obtain correct idle but as soon as you apply throttle to drive it-18.8% is the minimum throttle opening and hence minimum amount of airflow. So if we are applying 3% Pedal at cruise our total TP% is 18.8%+Pedal Percentage(3%) So that is 21.8% Total throttle.
If we reduce max idle area gradually until it drops to around 17%, You will notice at the same speeds with the same 3% pedal added(Total of 20%) The surging will be completely gone.
So in this case if there is to much airflow passing at low rpm surging will occur and reducing max idle area will fix the problem.
Having said that, Auto cars have Max Idle area 1 and Max idle area 2. Once Drive is selected it defaults to Max idle area 2, which has a crazy high figure of 3.0. This means when driving with only 3% pedal applied there may be a total percentage of over 25%! Surge city! The factory settings may be fine for a stock like camshaft with little reversion but with a camshaft starting to approach 0 degrees overlap @ 0.050" lift reversion starts to set in.
I have no dyno figures for you, but I have a 218/224/112+0 cam(.605",.601") xfi lobes in a L92 6.0L and it works awesome power hits hard, It is very aggressive when you want it to be and pulls from idle to 6600rpm and gets great economy. Sonny from Marranos spent $40000 dollars testing camshafts in aussie delivered L98s(6L with L92 heads and LS3 intake) and he told me he gets the best results with xfi lobes with L92 heads with small intake durations.
He told me the 218/224/112 cam is his favorite. I specced it up myself last year and I posted it on LS1.com.au in my sig and he asked me how it was going and that he had great real world results with this cam. Combined with SD tune and OTR intake and comp bump to 10.8:1 lets just say my brand new falken tyres are not looking good after only 3000kms, and I dont dump the clutch lol.
He also uses a 210 218 xfi cam and this cam is a stump puller.
He has been getting big power with the 224 230 112 and 114 cams on xfi lobes. I would like to try this too.
When tuning cammed L92 headed engines with an e38pcm, I find airflow adjustment is the only thing that dials out surging that occurs normally between 1200~1600rpm. It has an electronic TB(90mm). The e38 has a setting called max idle area. It shows up at 1.82 stock. This equates to 18.8% throttle opening. So if you are idling over the airflow correction may pull it back to 14% to obtain correct idle but as soon as you apply throttle to drive it-18.8% is the minimum throttle opening and hence minimum amount of airflow. So if we are applying 3% Pedal at cruise our total TP% is 18.8%+Pedal Percentage(3%) So that is 21.8% Total throttle.
If we reduce max idle area gradually until it drops to around 17%, You will notice at the same speeds with the same 3% pedal added(Total of 20%) The surging will be completely gone.
So in this case if there is to much airflow passing at low rpm surging will occur and reducing max idle area will fix the problem.
Having said that, Auto cars have Max Idle area 1 and Max idle area 2. Once Drive is selected it defaults to Max idle area 2, which has a crazy high figure of 3.0. This means when driving with only 3% pedal applied there may be a total percentage of over 25%! Surge city! The factory settings may be fine for a stock like camshaft with little reversion but with a camshaft starting to approach 0 degrees overlap @ 0.050" lift reversion starts to set in.
I have no dyno figures for you, but I have a 218/224/112+0 cam(.605",.601") xfi lobes in a L92 6.0L and it works awesome power hits hard, It is very aggressive when you want it to be and pulls from idle to 6600rpm and gets great economy. Sonny from Marranos spent $40000 dollars testing camshafts in aussie delivered L98s(6L with L92 heads and LS3 intake) and he told me he gets the best results with xfi lobes with L92 heads with small intake durations.
He told me the 218/224/112 cam is his favorite. I specced it up myself last year and I posted it on LS1.com.au in my sig and he asked me how it was going and that he had great real world results with this cam. Combined with SD tune and OTR intake and comp bump to 10.8:1 lets just say my brand new falken tyres are not looking good after only 3000kms, and I dont dump the clutch lol.
He also uses a 210 218 xfi cam and this cam is a stump puller.
He has been getting big power with the 224 230 112 and 114 cams on xfi lobes. I would like to try this too.
TECH Addict
Joined: Sep 2010
Posts: 2,898
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The LPE GT11 is a crap cam.
Soggy accelerator feel with soggy low and mid range torque.
Way too much split at 16 degrees and the 118LSA is way too high.
Never again.
Soggy accelerator feel with soggy low and mid range torque.
Way too much split at 16 degrees and the 118LSA is way too high.
Never again.
Launching!
Joined: Aug 2010
Posts: 242
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The big spit in duration is more from the combination of the fi intake and the rect port heads than just the heads. ls3 heads on a carbed motor run less of a split but still some due to the intake being so much better than the ex port on that head.
TECH Regular
Joined: Mar 2005
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Ya the 118 lsa is crap... I am going to run a brand new lunati grind just for the ls3 next month. 217/228 with a 112/108 rpm rang is 1800-6400
TECH Addict
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Sounds like a good cam. Should pull very well throughout the rev range.
Small duration cams work great with the square port heads.
I got a cam from Ed curtis 219/227 .625 .619 112LSA+4 for my beast.
So looking forward to installing it.
Ed knows his stuff
Small duration cams work great with the square port heads.
I got a cam from Ed curtis 219/227 .625 .619 112LSA+4 for my beast.
So looking forward to installing it.
Ed knows his stuff
Joined: Jul 2007
Posts: 1,500
Likes: 177
From: ELSA, South TEXAS (956) 802-7700
hmmmm. what kind of car and weight? tranny and stall?
Here is my LS2 dyno with the LPE GT-11 cam with LPE CNC 243 heads. The car idles at 675 rpm with virtually no lope or drop in torque. Hit the throttle at any RPM and it takes off with no hesitation.
Its the total combination not individual parts that make it work.
Last edited by Mez; Feb 4, 2012 at 09:00 AM.
TECH Addict
Joined: Sep 2010
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Hi everyone.
I thought to discuss my combination and get people's opinions on my setup.
I have an LS2 with CNC L92 heads and 11:8.1 compression, a ported FAST 102 manifold, 2200rpm stall converter, fully rebuilt 600HP 4L65E auto, thermostat, and a 219/227 .625 .619 112LSA+4 camshaft specced out by the man Ed Curtis of flowtech induction.
My goal is to have maximum torque at all rpm with an emphasis on low down torque as my car is a daily. the powerband of this cam is from 2000rpm-6200rpm. Ed goes the timing events for this setup are very precise and spot on and will work very well.
Peak power is not my main concern.
I have had a big camshaft before which made 470rwhp with same setup(stall speed was at 3200rpm back then) but drove like absolute crap along with having a very narrow power band. was from 3000-5000rpm then would drop off quick after that. Big cams are not for me especially for the street.
Would appreciate anyone's opinion feedback
I thought to discuss my combination and get people's opinions on my setup.
I have an LS2 with CNC L92 heads and 11:8.1 compression, a ported FAST 102 manifold, 2200rpm stall converter, fully rebuilt 600HP 4L65E auto, thermostat, and a 219/227 .625 .619 112LSA+4 camshaft specced out by the man Ed Curtis of flowtech induction.
My goal is to have maximum torque at all rpm with an emphasis on low down torque as my car is a daily. the powerband of this cam is from 2000rpm-6200rpm. Ed goes the timing events for this setup are very precise and spot on and will work very well.
Peak power is not my main concern.
I have had a big camshaft before which made 470rwhp with same setup(stall speed was at 3200rpm back then) but drove like absolute crap along with having a very narrow power band. was from 3000-5000rpm then would drop off quick after that. Big cams are not for me especially for the street.
Would appreciate anyone's opinion feedback
Hi everyone.
I thought to discuss my combination and get people's opinions on my setup.
I have an LS2 with CNC L92 heads and 11:8.1 compression, a ported FAST 102 manifold, 2200rpm stall converter, fully rebuilt 600HP 4L65E auto, thermostat, and a 219/227 .625 .619 112LSA+4 camshaft specced out by the man Ed Curtis of flowtech induction.
My goal is to have maximum torque at all rpm with an emphasis on low down torque as my car is a daily. the powerband of this cam is from 2000rpm-6200rpm. Ed goes the timing events for this setup are very precise and spot on and will work very well.
Peak power is not my main concern.
I have had a big camshaft before which made 470rwhp with same setup(stall speed was at 3200rpm back then) but drove like absolute crap along with having a very narrow power band. was from 3000-5000rpm then would drop off quick after that. Big cams are not for me especially for the street.
Would appreciate anyone's opinion feedback
I thought to discuss my combination and get people's opinions on my setup.
I have an LS2 with CNC L92 heads and 11:8.1 compression, a ported FAST 102 manifold, 2200rpm stall converter, fully rebuilt 600HP 4L65E auto, thermostat, and a 219/227 .625 .619 112LSA+4 camshaft specced out by the man Ed Curtis of flowtech induction.
My goal is to have maximum torque at all rpm with an emphasis on low down torque as my car is a daily. the powerband of this cam is from 2000rpm-6200rpm. Ed goes the timing events for this setup are very precise and spot on and will work very well.
Peak power is not my main concern.
I have had a big camshaft before which made 470rwhp with same setup(stall speed was at 3200rpm back then) but drove like absolute crap along with having a very narrow power band. was from 3000-5000rpm then would drop off quick after that. Big cams are not for me especially for the street.
Would appreciate anyone's opinion feedback