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Discussion Starter · #1 ·
i am not the greatest at picking a cam , so any help would be appreciated

ill prob end up going with a cam over winter just trying to get an idea now, just want a mild cam to help the car breath a bit better, im single turbo (also going to run a small shot .. prob 75 )
 

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Do you realize how many different combos can come up with a 112º LSA?
LSA (or LCA) means nothing. It is an 'oh by the way' figure.
You would be just as well labeling the LCA with colors of the rainbow.
You select the open/close points having regard for overlap and duration, and the LCA falls where it falls.
I have yet to find or communicate with a pro, be it an actual cam designer (a real one, not a wanna be like BB) or pro tuner
that will be in disagreement with me. What is printed in auto rags and books of today is often misleading and intended to dumb
down the reader.

On the other side of the coin, I have yet to find anyone (including the highly regarded high post gurus) on this forum that will
agree with me.
 

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Posting ONLY to re-enforce my above post and NOT to rub it in, a well known NASCAR engine builder stated in regards to the LCA/LSA, “Take every lobe separation you’ve ever seen run with your application, place them on a dart board, close your eyes and throw. That is how relatively important this spec is.”

In his soft cover book regarding cams and their related hardware, Vizard, a writer highly regarded by some on this forum, suggested the appropriate open/close and OL specs for a turbo application and the LCA/LSA ended up being in the mid 120s. Lingenfelter had one over 120º for the LCA spec on one of his turbo cams as well. Not stating either cam is the most appropriate, just stating the LCA can end up anywhere. It means next to nothing on the list of important cam specs. This applies to any application, FI or NA.

If someone inquires about the specs of a given cam you wish to remain unknown or secret, just state what the LCA/LSA is, as that spec reveals nothing about the cam specs. :)
 

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i am not the greatest at picking a cam , so any help would be appreciated

ill prob end up going with a cam over winter just trying to get an idea now, just want a mild cam to help the car breath a bit better, im single turbo (also going to run a small shot .. prob 75 )
I know u said mild, and this is a tab bit on the larger side, but a turbo cam spec 236/242 112
 

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Something also to consider is the lift. A lot of turbo motors don't need cams with crazy lift in order to perform well. For example: My cam is a 232/240 @.050 .595/.608 and a 115 LSA.

But then again, what works for one build, might not work for another. Too many variables to really have a definite answer IMO.
 

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Something also to consider is the lift. A lot of turbo motors don't need cams with crazy lift in order to perform well. For example: My cam is a 232/240 @.050 .595/.608 and a 115 LSA.

But then again, what works for one build, might not work for another. Too many variables to really have a definite answer IMO.
Tru, mine is around .580 lift, and comp cams said, it's the biggest turbo cam I could get from them. Mine is a tru monster, and street manners r good, even drove her in the rain
 

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Do you realize how many different combos can come up with a 112º LSA?
LSA (or LCA) means nothing. It is an 'oh by the way' figure.
You would be just as well labeling the LCA with colors of the rainbow.
You select the open/close points having regard for overlap and duration, and the LCA falls where it falls.
I have yet to find or communicate with a pro, be it an actual cam designer (a real one, not a wanna be like BB) or pro tuner
that will be in disagreement with me. What is printed in auto rags and books of today is often misleading and intended to dumb
down the reader.

On the other side of the coin, I have yet to find anyone (including the highly regarded high post gurus) on this forum that will
agree with me.
Posting ONLY to re-enforce my above post and NOT to rub it in, a well known NASCAR engine builder stated in regards to the LCA/LSA, “Take every lobe separation you’ve ever seen run with your application, place them on a dart board, close your eyes and throw. That is how relatively important this spec is.”

In his soft cover book regarding cams and their related hardware, Vizard, a writer highly regarded by some on this forum, suggested the appropriate open/close and OL specs for a turbo application and the LCA/LSA ended up being in the mid 120s. Lingenfelter had one over 120º for the LCA spec on one of his turbo cams as well. Not stating either cam is the most appropriate, just stating the LCA can end up anywhere. It means next to nothing on the list of important cam specs. This applies to any application, FI or NA.

If someone inquires about the specs of a given cam you wish to remain unknown or secret, just state what the LCA/LSA is, as that spec reveals nothing about the cam specs. :)
Damn Gary, I'm kind of proud of you. Your're really trying. While both of these posts were somewhat pertinant to the question asked, you wasted alot of "breath" negatively expaounding on Tugg's post. Try bypassing, or merely remarking on what you previously expounded upon, then submit remarks based upon personal experience, or information based upon "known facts" to be passed on to the originator of this communicative submission. Be personable. Positive issuance and reinforcement works better than the condescending post above.


To the OP. Many, and I mean MANY factors contribute what makes a cam more mild versus another. Gary is quite correct about LSA/LCA. Its a term used too frequently and it is overused. The camshaft specification services offered by most of the camshaft services the LT1 community uses are relatively priced. The outcome of tha selection is by far and above wha you would expect out of a "normal" camshaft selection. I cannot express how MANY variable there are to take into consideration when selecting a cam. Lets try a few questions. What size engine, what size turbo, what is your target power output/expectation(<very important considerations), operating conditions, intended use, compression ratio, head flow data, exhaust system configuration, emission compatablility. Lets start with those.


Your fellow systems developement technician,

Chris
 

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Discussion Starter · #10 · (Edited)
sorry guys didnt mean to start a battle

by next spring id like to have the car very deep into the 10s, i would guess rwp 650 ish is what id like to see, but want the car to be streetable because i love to drive it

heres mods

9.5 to 1 355 forged interals-1.6 roller rocker- aluminum camaro heads little cleaning- 58 mm t/b-t66- 3.5 downpipe to an e cutout then y to a dual 3"-nx kit (prob run a dry 75 shot ) and 3.42s , cant think of anymore right now

i have my buddy who fabs finishing the exhaust and all new turbo piping as we speak so , havent had much test and tune with the bigger turbo and more flow exhaust yet

getting a list of things i want to do over winter and a cam is on it

thank you guys for the advice, im here to learn what i dont know and its appriciated
 

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My cam is 112lsa but I sure mines a differant animal. Why not call up comp cams and have them spec something out.
 

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Damn Gary, I'm kind of proud of you. You're really trying. While both of these posts were somewhat pertinent to the question asked, you wasted alot of "breath" negatively expounding on Tugg's post.
My negativity, as you perceive it, can be likened to LCA.
I do not care to expand on the favorable comparison or explain myself.
I don't see the point, nor do I see the gain, Chris.
I do however agree with you on one point, this forum is what it is.
 

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Gary,

I never asked you to explain yourself. You should never have too, to anyone for any reason. I also did not comment on "your negativity", just the flavor of the particular posts. This forum is what it is. Made up of many different people. I personally wouldn't want you to change. I kind of enjoy watching you make people think so hard about themselves, they can't think straightcwm7. Its kind of funny seeing them melt down enough they start to chew on the carpet.



To the OP sorry for the "jack", just happened to be the place that i could communicate with this guy without too much interruption.

Chris
 

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sorry guys didnt mean to start a battle

by next spring id like to have the car very deep into the 10s, i would guess rwp 650 ish is what id like to see, but want the car to be streetable because i love to drive it

heres mods

9.5 to 1 355 forged interals-1.6 roller rocker- aluminum camaro heads little cleaning- 58 mm t/b-t66- 3.5 downpipe to an e cutout then y to a dual 3"-nx kit (prob run a dry 75 shot ) and 3.42s , cant think of anymore right now

i have my buddy who fabs finishing the exhaust and all new turbo piping as we speak so , havent had much test and tune with the bigger turbo and more flow exhaust yet

getting a list of things i want to do over winter and a cam is on it

thank you guys for the advice, im here to learn what i dont know and its appriciated

A solid average power of 700 hp to get a 4400 lb car, with a 355, run in the 10's. From that you can calculate a rough cfm for airflow to and through the engine and calculate port flow, piping flow, intercooler flow and pressure drop, and finally the restriction measurement(targeted boost in psi/gauge). From some more math you can figure out the best converter and gear ratio. A 6700 rpm upshift and rev through the lights with a 30 inch tire would need a 4.56 gear in the rear. I'd leave the nitrous and pursue methanol injection instead, and in conjunction with a good charge air cooler.

Chris
 

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Gary,

I never asked you to explain yourself. You should never have too, to anyone for any reason. I also did not comment on "your negativity", just the flavor of the particular posts. This forum is what it is. Made up of many different people. I personally wouldn't want you to change. I kind of enjoy watching you make people think so hard about themselves, they can't think straightcwm7. Its kind of funny seeing them melt down enough they start to chew on the carpet.



To the OP sorry for the "jack", just happened to be the place that i could communicate with this guy without too much interruption.

Chris
Sorry Yoko,

so Chris you believe his post had that type of effect on me? Because I've heard the same thing before, from racers perspective...that is trying to squeeze every last hp out their application...u guys can walk around with your chests poked trying to bash people all you want...it doesn't bother me, I have a turbo impala in the single digits, my goal, which happens to have a 112 LSA cam...
 

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Discussion Starter · #16 ·
A solid average power of 700 hp to get a 4400 lb car, with a 355, run in the 10's. From that you can calculate a rough cfm for airflow to and through the engine and calculate port flow, piping flow, intercooler flow and pressure drop, and finally the restriction measurement(targeted boost in psi/gauge). From some more math you can figure out the best converter and gear ratio. A 6700 rpm upshift and rev through the lights with a 30 inch tire would need a 4.56 gear in the rear. I'd leave the nitrous and pursue methanol injection instead, and in conjunction with a good charge air cooler.

Chris
thank you one of the reason im running nitrous is because i run a purge bar over the i/c , it helps heat soak and cools the i/c and radiator, it runs double duty instead of wasting and venting to the atmosphere
 

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Sorry Yoko,

so Chris you believe his post had that type of effect on me? Because I've heard the same thing before, from racers perspective...that is trying to squeeze every last hp out their application...u guys can walk around with your chests poked trying to bash people all you want...it doesn't bother me, I have a turbo impala in the single digits, my goal, which happens to have a 112 LSA cam...
My comments were meant for Gary. I bash no one. And those whose skin that Gary get under need to grow a thicker epidermal layer. Everyone makes thier own choices. No two engines, setups or drivers will, or would choose the same cam. So for that pass/fail is a self dependant result. Good for you for the single digit turbo car.

Chris
 

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9.5 to 1 355 forged interals-1.6 roller rocker- aluminum camaro heads little cleaning- 58 mm t/b-t66- 3.5 downpipe to an e cutout then y to a dual 3"-nx kit (prob run a dry 75 shot ) and 3.42s , cant think of anymore right now
I had Comp spec a cam for my application, you should ask them... it's free!

I have a 9.4:1 355ci with 6.00" rods, cleaned up aluminum heads (stock valve size, no porting), 1-5/8" headers with twin T3/T4 turbos (0.82 AR turbine housings) with 2.5" downpipes and exhaust, 3.23 gears, TH400.

They suggested I get this cam:

Part #: 07-000-8
Grind #: LT1 3015/3015 HR113+4
Duration @ .050”: 224/224
Lift w/ 1.6 Ratio: .573/.573
LSA: 113
Advance: +4

Hope this helps. :)
 

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I had Comp spec a cam for my application, you should ask them... it's free!
Guillaume, unfortunately, and this has been documented numerous times on a Camaro site, calling CC for cam advice can yield as many different cam/cam spec recommendations as phone calls. Apparently, the people answering the phones are neither experts nor cam designers. Granted, specing a cam is not an exact science, but nonetheless, if the source was of reasonable competency you'd get a reasonably consistent recommendation for a given application. Maybe the engine info being offered by the potential cam buyer is hit and miss, I don't know. Regardless, it is no wonder this forum subscribes to misinformation and the average enthusiast is in the dark or not as knowledgeable as they might believe when the source, whether it is a phone rep assigned to the call can be as much in the dark, or cam related info offered on their site is not as accurate as it could be.
 

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...and I installed the recommended cam in my engine. Hope it works as good as it should. :(
 
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