Difference in cam selection between M6 and A4?
#1
Difference in cam selection between M6 and A4?
I've been reading the internal section for quite a while and have noticed that the trans has a part in picking the cam, but I'm not quite sure what it is.
The only thing I can assume is, it's easier to DD a bigger cam in a manual car because you don't have to worry about it pushing through the brakes at stop lights?
Other than that I'm not sure what to gather with reading in between the lines.
The only thing I can assume is, it's easier to DD a bigger cam in a manual car because you don't have to worry about it pushing through the brakes at stop lights?
Other than that I'm not sure what to gather with reading in between the lines.
#2
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Most decent size cams do not make power near a stock stall. Instead they make the most power at high rpm. Thus the reason why most automatics have a larger stall to cut down on the time it takes to reach your cams power range.
#3
No the trans does not matter. With LS motors anyone that understands how stalls work is going to put in between a 3600 and 4400 stall. So really any cam you throw at that will be fine, pick your cam based on rpm range
#4
Basically what blk98 said, pick your cam for an auto, then match the correct converter for the cam and you will have a good running car....plus if you cam and stall an auto you NEED a tranny cooler because higher stalls create more heat and heat kills auto trannys....quick
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Tranny will matter to an extent. If you have an auto, you'll want a lower lsa cam (i.e. 111 or 112 lsa). If you have a m6, a 113 or 114 lsa will suffice. This will broaden your power band. Not to say you HAVE to do this, but from my experience, I've found it to be true.
#6
I have read the 113-114 LSA for the M6 (Which I have) numerous times, and I am wondering why it would differ from an A4 (proper converter given).
Is this "broscience" or why the LSA differences based on the trans?
(I apologize for the vague OP, wife was rushing me out of the house and I wasn't sure how to ask it exactly.)
#7
The wider the lsa is the broader your powerband, but power will come in later...the narrower your lsa the narrower your powerband will be, but you will have a higher peak torque, and peak torque will come in sooner.
A manual tranny is a lot more forgiving on itself at higher rpms and takes roughly 15%+-
An auto tranny starts having issues an fluid flow problems at higher rpms unless you do a lot of work to correct/adjust the fluid and pressure problems, plus LOTS more parts, check *****, butt loads of clutches to go out or be eaten....auto trannys burn roughly 25% of your engines power.
Just some facts that might help.
A manual tranny is a lot more forgiving on itself at higher rpms and takes roughly 15%+-
An auto tranny starts having issues an fluid flow problems at higher rpms unless you do a lot of work to correct/adjust the fluid and pressure problems, plus LOTS more parts, check *****, butt loads of clutches to go out or be eaten....auto trannys burn roughly 25% of your engines power.
Just some facts that might help.
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#8
One big factor is you torque converter acts kind of like a cushion in the drivetrain.....if the car starts to buck at low rpms, all you have to do is tap the brake and the converter unlocked letting everything slip a bit
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Stall speed for autos, rear gear ratio, vehicle weight, and intended use and rpm range are bigger factors for me suggesting a cam then actual transmission.
#11
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^^^i totally agree with him...there are a lot of factors when picking a cam IF you want the total package (power, torque, driveability, reliability, long life, etc)...it's easier if you are building a race car then You just have to pick the biggest cam possible to match the cubes you got..