View Poll Results: ew Cam Or Heads?
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Multiple Choice Poll. Voters: 15. You may not vote on this poll
cam selection help
04-25-2009, 03:50 PM
#21
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I'm a BIG fan of aggressive ramps too and just ordered and received a custom ground CompCams HR that I selected designed for high/broad torque and fast ramps in mind.
Of course I used the $500 Engine Analyzer Pro simulation program to fine-tune my selection, which, by the way, told me my heads - Dart Pro 1s - prefer a single pattern cam as opposed to a split-duration cam. Has to do with how well the exhaust ports on the heads flow.
Anyway, one of the tricks I use is to subtract the .050 duration from the advertised duration. The smaller/lower the difference, the more aggressive the ramps. Be careful though, you need to be sure that the advertised durations are measured at the same point (apples to apples). For Comp's profiles I selected lobes measured at .006 for their advertised duration.
Faster ramps will be in the 51/52 range for HR cams.
I'd like to know what your goal(s) are for the engine.
For my son's 350, 96 LT1 we're looking for torque, torque and more torque and decided to let the HP fall where it may.
If you want to, check out the March 2008 issue of Chevy High-Performance magazine. The articles may be on their website and is pretty much dedicated into camshaft selection. Has interviews with a few of the cam gurus from Lunati, Crane and CompCams.
Out of the cams you listed, from memory, the XFI and LPE cams have the most aggressive ramps. CompCams Godbold at the time of the interview said the XFI lobes are the best they've ever done.
As far as heads, look at flow numbers Vs port volume and not just max flow but how well they flow at low and mid lift ranges. Don't forget to consider the size of the combustion chambers, since that'll effect CR. Every point difference in CR translates into 3-4 percent in power difference.
Hope this helps.
Jake
West Point ROCKS!
Of course I used the $500 Engine Analyzer Pro simulation program to fine-tune my selection, which, by the way, told me my heads - Dart Pro 1s - prefer a single pattern cam as opposed to a split-duration cam. Has to do with how well the exhaust ports on the heads flow.
Anyway, one of the tricks I use is to subtract the .050 duration from the advertised duration. The smaller/lower the difference, the more aggressive the ramps. Be careful though, you need to be sure that the advertised durations are measured at the same point (apples to apples). For Comp's profiles I selected lobes measured at .006 for their advertised duration.
Faster ramps will be in the 51/52 range for HR cams.
I'd like to know what your goal(s) are for the engine.
For my son's 350, 96 LT1 we're looking for torque, torque and more torque and decided to let the HP fall where it may.
If you want to, check out the March 2008 issue of Chevy High-Performance magazine. The articles may be on their website and is pretty much dedicated into camshaft selection. Has interviews with a few of the cam gurus from Lunati, Crane and CompCams.
Out of the cams you listed, from memory, the XFI and LPE cams have the most aggressive ramps. CompCams Godbold at the time of the interview said the XFI lobes are the best they've ever done.
As far as heads, look at flow numbers Vs port volume and not just max flow but how well they flow at low and mid lift ranges. Don't forget to consider the size of the combustion chambers, since that'll effect CR. Every point difference in CR translates into 3-4 percent in power difference.
Hope this helps.
Jake
West Point ROCKS!
04-25-2009, 04:05 PM
#22
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update: how does this sound?
Patriot Performance is proud to announce their new aluminum190cc LT1 head. We have designed these heads to work well on 350-383 LT applications. The heads were designed to use a stock LT1 intake. Heads come assembled with our famous Patriot Gold .650” hydraulic roller springs, titanium retainers, 2.02”/1.60” stainless valves. bronze guides, viton rubber seals, 3/8” studs, and guide plates.
Sold As Pair
Technical Specs:
Combustion Chamber: 58cc
Intake Runner: 195cc
Exhaust Runner: 70cc
Intake Valve: 2.02"
Exhaust Valve: 1.60"
Max. Valve Spring Lift: 0.650"
Spring Pressure Closed: 135 lbs. @ 1.800"
Spring Pressure Open: 375 lbs. @ 1.150"
Retainer Material: Titanium
Valve Seal Material: Viton
Valve Guide Material: Manganese Bronze
Valve Job: 5-angle
heres the link https://www.patriot-performance.com/...1&cat=0&page=1
Patriot Performance is proud to announce their new aluminum190cc LT1 head. We have designed these heads to work well on 350-383 LT applications. The heads were designed to use a stock LT1 intake. Heads come assembled with our famous Patriot Gold .650” hydraulic roller springs, titanium retainers, 2.02”/1.60” stainless valves. bronze guides, viton rubber seals, 3/8” studs, and guide plates.
Sold As Pair
Technical Specs:
Combustion Chamber: 58cc
Intake Runner: 195cc
Exhaust Runner: 70cc
Intake Valve: 2.02"
Exhaust Valve: 1.60"
Max. Valve Spring Lift: 0.650"
Spring Pressure Closed: 135 lbs. @ 1.800"
Spring Pressure Open: 375 lbs. @ 1.150"
Retainer Material: Titanium
Valve Seal Material: Viton
Valve Guide Material: Manganese Bronze
Valve Job: 5-angle
heres the link https://www.patriot-performance.com/...1&cat=0&page=1
Are those heads priced EACH or for the PAIR?
If EACH, skip 'em. You can get equal or better offerings for less $$. Even AFR Eliminators can be bought cheaper.
Jake
West Point ROCKS!
04-25-2009, 05:29 PM
#23
Don't take a cam recommendation from anyone until you answer some important questions. Your poll is comparing alot of apples to oranges so this will help you get on track.
Emissions a concern?
Weekend warrior or daily driver?
Manual or Auto?
If Auto what stall size?
Gears?
How high are you willing to rev the stock bottom end to?
Looking for alot of bottom-end torque? strong mid-range? alot of top-end?
And yes you will need a tune. What valve train you will need is in the guide.
Emissions a concern?
Weekend warrior or daily driver?
Manual or Auto?
If Auto what stall size?
Gears?
How high are you willing to rev the stock bottom end to?
Looking for alot of bottom-end torque? strong mid-range? alot of top-end?
And yes you will need a tune. What valve train you will need is in the guide.
