Disappointed after modifications!
04-27-2009, 02:27 PM
#81
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Don't get too down on your combo yet. I have a similar cam (33x/34x on a 109LSA) in a stock TPI short block with a mini ram and AFR 190 heads (ported). I shift at 6500RPM, and the cam is still pulling (the driver is scared of destruction!). The car has gone 11.66 at 117 and put down in the neighborhood of 380RWHP. I only have 30lb injectors. I think the shorties are killing you. A cam with a tight LSA (and lots of overlap) really needs the scavenging affect that full-lengths provide. Also, looking at your Dyno run, it appears that the operator stopped at about 6200RPM...WHY? It should make power past that point. However, your valve train needs to accomodate the RPM. What is your valve train setup?
04-27-2009, 02:35 PM
#82
Don't get too down on your combo yet. I have a similar cam (33x/34x on a 109LSA) in a stock TPI short block with a mini ram and AFR 190 heads (ported). I shift at 6500RPM, and the cam is still pulling (the driver is scared of destruction!). The car has gone 11.66 at 117 and put down in the neighborhood of 380RWHP. I only have 30lb injectors. I think the shorties are killing you. A cam with a tight LSA (and lots of overlap) really needs the scavenging affect that full-lengths provide. Also, looking at your Dyno run, it appears that the operator stopped at about 6200RPM...WHY? It should make power past that point. However, your valve train needs to accomodate the RPM. What is your valve train setup?
You could improve your ETs and overall HP output by using an appropriately sized cam.
B) By shifting it at 6500, you're running a significant risk of spinning a bearing.
I'm not telling you not to do it, but I want people who read this thread to understand that it's playing with fire.
Start saving for your rebuild and new rotating assembly now.
04-27-2009, 03:10 PM
#83
Launching!
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Been down the track about 50 times in the last two years (don't know how many times before that). I didn't build the car. Traxion and Joe Overton did. Runs pretty good I'd say. I agree though, it could go at any time.
04-27-2009, 03:27 PM
#84
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Don't get too down on your combo yet. I have a similar cam (33x/34x on a 109LSA) in a stock TPI short block with a mini ram and AFR 190 heads (ported). I shift at 6500RPM, and the cam is still pulling (the driver is scared of destruction!). The car has gone 11.66 at 117 and put down in the neighborhood of 380RWHP. I only have 30lb injectors. I think the shorties are killing you. A cam with a tight LSA (and lots of overlap) really needs the scavenging affect that full-lengths provide. Also, looking at your Dyno run, it appears that the operator stopped at about 6200RPM...WHY? It should make power past that point. However, your valve train needs to accomodate the RPM. What is your valve train setup?
04-28-2009, 06:53 AM
#85
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Valve train setup sounds good (very similar to mine). If it were me, I'd try the long tube headers next. I have Hooker Super Comps (1 3/4" into a 3" collector). That would be about the size you would want. Try buying a cheap, used pair first if you can. If they work out, then spend the money on stainless or ceramic coated ones when the funds allow.
04-28-2009, 10:29 AM
#86
I think its a shame people are bashing the head porter since they do not know who he is! You can have an awesome set of heads with mismatched compression and cam selection that can cause this. I feel the cam is too large for the compression NOT the CI.....The heads could be ported in such a way where they have had the flow destroyed!
At this point it ould be less expensive to do a cam swap that will work well with the compression you have. If it still does not run then i would think strongly about sending your current heads out to one of the very well trusted gurus to see if they can be salvaged...
At this point it ould be less expensive to do a cam swap that will work well with the compression you have. If it still does not run then i would think strongly about sending your current heads out to one of the very well trusted gurus to see if they can be salvaged...
04-28-2009, 03:16 PM
#87
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When it comes to his cam, there are just too many "x"s after the first two numbers. Those last digits are incredibly important.
Guys, please, resist the temptation of throwing in an "x" when posting your numbers. That is, unless you don't care about the accuracy of the responses.
Are we talking 249 @ .050 or 240? Is the LSA 100 or 109? BIG differences!
Absence of torque tells me too much duration; cam's about 2-1/2 - 3 sizes too big for the CID and desired RPM range.
Remember HP is not measured, it's only calculated. It's TORQUE and RPM and the mathematical constant (5252) that determines HP.
The most common mistake made in camshaft selection is choosing one with too much duration. Check the Chevy High-Performance mag, March, 2008 issue to read all about it from interviews with the cam gurus from Lunati, CompCams and Crane.
Jake
West Point ROCKS!
Guys, please, resist the temptation of throwing in an "x" when posting your numbers. That is, unless you don't care about the accuracy of the responses.
Are we talking 249 @ .050 or 240? Is the LSA 100 or 109? BIG differences!
Absence of torque tells me too much duration; cam's about 2-1/2 - 3 sizes too big for the CID and desired RPM range.
Remember HP is not measured, it's only calculated. It's TORQUE and RPM and the mathematical constant (5252) that determines HP.
The most common mistake made in camshaft selection is choosing one with too much duration. Check the Chevy High-Performance mag, March, 2008 issue to read all about it from interviews with the cam gurus from Lunati, CompCams and Crane.
Jake
West Point ROCKS!
04-28-2009, 03:21 PM
#88
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He needs 1.1 to 1.2 HP and 1.1 to 1.2 ft/lbs of torque per cubic inch to even be in the ballpark.
Crunch the numbers and see where the engine, at a minimum, should be.
Jake
West Point ROCKS!
Crunch the numbers and see where the engine, at a minimum, should be.
Jake
West Point ROCKS!
04-28-2009, 03:33 PM
#89
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When it comes to his cam, there are just too many "x"s after the first two numbers. Those last digits are incredibly important.
Guys, please, resist the temptation of throwing in an "x" when posting your numbers. That is, unless you don't care about the accuracy of the responses.
Are we talking 249 @ .050 or 240? Is the LSA 100 or 109? BIG differences!
Absence of torque tells me too much duration; cam's about 2-1/2 - 3 sizes too big for the CID and desired RPM range.
Remember HP is not measured, it's only calculated. It's TORQUE and RPM and the mathematical constant (5252) that determines HP.
The most common mistake made in camshaft selection is choosing one with too much duration. Check the Chevy High-Performance mag, March, 2008 issue to read all about it from interviews with the cam gurus from Lunati, CompCams and Crane.
Jake
West Point ROCKS!
Guys, please, resist the temptation of throwing in an "x" when posting your numbers. That is, unless you don't care about the accuracy of the responses.
Are we talking 249 @ .050 or 240? Is the LSA 100 or 109? BIG differences!
Absence of torque tells me too much duration; cam's about 2-1/2 - 3 sizes too big for the CID and desired RPM range.
Remember HP is not measured, it's only calculated. It's TORQUE and RPM and the mathematical constant (5252) that determines HP.
The most common mistake made in camshaft selection is choosing one with too much duration. Check the Chevy High-Performance mag, March, 2008 issue to read all about it from interviews with the cam gurus from Lunati, CompCams and Crane.
Jake
West Point ROCKS!
04-28-2009, 04:51 PM
#90
