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Shift point question for new cam

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Old 06-15-2010, 09:44 PM
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Question Shift point question for new cam

I'm trying to figure out my new cam for best results. I've got an idea of what I need to do, but figured I'd ask for confirmation. The attached dyno shows my HP&T curve. Some of it's hard to read, but I figure I should shift 1 to 2 by 5k since that’s where my torque starts to dip down and the rest of my shifts at 6.5k. Sound reasonable?
Attached Thumbnails Shift point question for new cam-200-ishift.jpg  
Old 06-16-2010, 08:10 AM
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Suggest a detailed log of each run, shift points, weather, tire psi, launch info, yadda yadda, and go from there...See what the engine likes.
Maybe start here??
https://ls1tech.com/forums/drag-raci...-software.html
Old 06-16-2010, 08:21 AM
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Unless HP is dropping dramatically after 5k, you should be shifting @ or near redline. The thought process is that when you hit the next gear your be up higher on your curve and will not lag trying to move the car.
Old 06-16-2010, 08:33 AM
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To me even at 6500 it still doesn't look like its about to level off or start to nose down. But if the valvetrain and oil pump can take it I'd say shift close to 7k. If the springs are stock I don't know how high you can safely spin an LS1 though.

Whats the specs on the cam?

-Mark
Old 06-16-2010, 08:37 AM
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6800-7000
Old 06-16-2010, 09:59 AM
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6700 easily.
Old 06-16-2010, 10:54 AM
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how about this, when your racing me, Shift @ 5k and I'll shift at redline and see what happens
Old 06-16-2010, 02:59 PM
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Roughly 6700-6900 go to the track and see what works best.
Old 06-16-2010, 03:17 PM
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I have always heard/been told that you want to shift a couple hundred rpm beyond your power peak. The graph shows that your peak power is at ~6700rpm so I would shift the car between 6900-7000rpm at every gear assuming you have the valvetrain to handle it.
Old 06-16-2010, 06:47 PM
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Thanks for all the good feed back. To answer some of the questions asked... I'm not running stock springs. My springs came as a set along with the AFR heads. I don't have the duration of the CAM, but i've attached a sheet that provides some information (G5X3 114LSA).

It looks like most of the comments with recommend my shifting higher than I had noted, but that's fine. This setup should permit me to redline at 7k so shifting around 6.8k should be good. I guess I'm a little conservative at times.

All this being said. I'm also looking for a good shift light. It's difficult to watch the strip and the RPM guage safely. Any comments about the Autometer brand of shift lights (Digital Pro Shift System
Shift Light, Level 1)?

Oh and "BlackScreaminMachine", I'll be sure to keep your comment in mind if I ever run into you at the track. '

Thanks guys, have a good one.
Attached Thumbnails Shift point question for new cam-g5x3.jpg  
Old 06-16-2010, 08:28 PM
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Assuming he has the valve train to handle high shifts, aren't any of you guys worried about the rod bolts stretching? I had my shift points adjusted to 6600 and the shift time to .25. I have the valve train and oil pump to handle it all, but was still worried to take it to high because I heard the rod bolts would stretch, especially in 98 models.
Old 06-17-2010, 09:53 AM
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I have heard a lot of good things about the raptor shift light. I have one, but hav'nt installed it yet. So I can't give you any personal feedback on it.
Old 06-17-2010, 10:14 AM
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The one thing I see being a benefit is in road racing or Auto-x where knowing the sweet spot of the car. Please correct me if I am wrong but I see given the graph that the amount of power being applied will vary during the race and come in and out of a turn will benefit from having the power matched up correctly and when accelleration again occurs then the driver will decrease over all lap time.
Old 06-17-2010, 10:27 AM
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definitely get a shift light installed before hitting the track. the stocker seems to be alittle slow and by the time it would show 6800 you will probably be on the limiter.i'd start around 6800 and go up 100 rpm at a time and see if time improves or slows down. as for a shift light i like my little raptor. small and out of the way,unlike one of those bulky 5" monsters.
Old 06-17-2010, 01:29 PM
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6800 with stock rod bolts in a 2000 model LS1 is where I would/plan to shift. I need injectors more than I need a shift light at this point in time, but I plan on either getting Auto Meter 5343 OR Summit's version, just not sure how good the Summit brand is, and its about 55% of the cost. I have heard nothing but good things about the Raptor shift lights, I just wouldn't mind a digital read out with the light in the same compact size.
Old 06-17-2010, 01:53 PM
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Raptor is the ****. Love mine.
Old 06-17-2010, 09:28 PM
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Originally Posted by second_2_none
Assuming he has the valve train to handle high shifts, aren't any of you guys worried about the rod bolts stretching? I had my shift points adjusted to 6600 and the shift time to .25. I have the valve train and oil pump to handle it all, but was still worried to take it to high because I heard the rod bolts would stretch, especially in 98 models.
I upraged my rods when I did the head install. I also upgrade my oil pump. "worried about the rod bolts stretching?" Do you mean the rocker bolts? These are stock. I moved them from my stock heads to the new heads.
Old 06-17-2010, 09:33 PM
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Originally Posted by 94Z28rag
Raptor is the ****. Love mine.

Just checked out the Raptor web site. I like what I'm seeing so far and it's less expensive than autometer. I'll do a little more reading.

Thanks
Old 06-17-2010, 09:37 PM
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Im shfting mine at 6800,same cam.Works for me.
Old 06-18-2010, 09:19 AM
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Originally Posted by captainwizbang
I upraged my rods when I did the head install. I also upgrade my oil pump. "worried about the rod bolts stretching?" Do you mean the rocker bolts? These are stock. I moved them from my stock heads to the new heads.
No I am talking about the connecting rod bolts. I know the 98 models are the worst. If you wrap the engine out to high of an rpm all the time they will stretch and your pistons will slap your valves and mess up a whole lot, pistons, valves, push rods, lifters, and possibly your cam, and heads. Ask me how I know.


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