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Discussion Starter #1
Got a 23 deg. sbc with what I think may be a lift issue. The lift on the intake is .680 with a 1.5 rocker and .608 ex, The motor had a 1.6 on the intake giving it .725I and 1.5E rocker keeping it.608E, That has to be bad right? Should i go 1.5 on the intake and 1.6 on exhaust and have .680I and .644E or 1.6 all the way across and have .725I/.644E
 

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Before we can answer. What's the spec's on the heads? Whats the CS at the pinch? Thats a pretty big split, 1.6 across the board looks better if the cam was designed for it and or will work with what you got. Whats the problem????
 

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I would like to know the rest of the cam profile, like Duration @ .050" and lsa/intake center..As for the lift, I run .680"/.640" in the basic bracket 13.1 406's with 227 heads and I run 1.6's across the board for .725"/.685". Nitrous doesn't care what the heads rated flow number is and lift is always good when running the hit. I would run the 1.6 on both unless the cam is way off..LMK.
 

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Not only is that alot of spread on the exhaust, but the duration is tremendous for this application. Way too much duration, and too little lift on the exhaust side. The lsa seems real wide as well. How much spray to you use? If it is under 300, I would cam it to run n/a, which will make this engine run faster and won't need as much spray to run the same. A camshaft like this seems to be way off for the combination. What intake and carb? LMK.
 

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is there flow #s for the heads.if there stock look at the factory flow #s.does the head drop off at a certain lift?. no use putting in more intake lift if the flow falls off.
 

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Discussion Starter #8
Spraying 300. 2 kits, 150 ea. Dart cnc 4500 intake, 1050 dominator, First stage seemed to respond well, Second on picked up 2 tenth's blowing through converter, Dont know the flow #s past .700
 

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10.3 @ 131 has no mph............... A 100hp shot should have got you to 142 with no problem. I'd seriously look at changing that convertor first. Your car ET's and MPH's more like an NHRA Stocker. Leaves hard but running outta breath on the top end.

That is a strange cam. What are you spinning it to?

If I run 10.3 (depends on the air) I will be going 133-134 (3300lbs). A 150hp shot gets me to 9.4 @ 146 (.063N jet). A 300hp shot (.030's x 8) will get me high 8's @ over 152. The gains really start to diminish past a 200hp shot on me since it really isn't a nitrous combo.
 

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Nitrous won't care what the flow numbers are, as you need volume for spray. Personally I would go with another grind, but I would pay more attention to the converter issue first. Most of the 23*, even out of the box works well to .700" lift and in bracket engines, I tend to get a bit more lift, usually about 15%-20% more lift than what the heads are good to. Low .700"'s is about it with them unless they are a big runner. However in a nitrous application, it doesn't really matter. When you have 300 worth of nitrous going through that runner,and it is a spray only application, you can up the lift on the profile for the spray and it will like it, even if the port stops "flowing" at a certain lift number.

As for what you gain, every engine combination will be different. To say he or you or they have gained such and such won't matter. 131 mph is actually high mph for a 10.30 pass.Just means the car isn't getting out the hole. Power adders usually always give you more mph because it is making HP, even if it doesn't 60 very well. Especially running in a heavy car as it is tougher to get the weight moveing. You should be able to hit it with 300 out the gate which will net better results, and if you are on a small drag radial, tune it to leave the best. Nitrous sees biggest gains from hitting it out of the hole. What are you shifting at on the hit and what is the converter you are running?
 

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Discussion Starter #13
Got a new FTI NOS converter, Was shifting at 7200. Car was going 1.34 60ft leaving with first 150 off the brake. Street/Strip 69 camaro with cal trac rear setup, TRZ front, 275/60/15.. BIR are you using the comp cam 279/286? I was looking at it and your specs look simular....Thanks for reply's
 

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Got a new FTI NOS converter, Was shifting at 7200. Car was going 1.34 60ft leaving with first 150 off the brake. Street/Strip 69 camaro with cal trac rear setup, TRZ front, 275/60/15.. BIR are you using the comp cam 279/286? I was looking at it and your specs look simular....Thanks for reply's

What is the flash rpm of the new converter? I would hit the full 300 out the gate and tune it to work on the drag radial with timing and suspension. You won't gain as much hitting the send stage later in the run. If you are shifting say 7k on the hit, and run a 300 hit, I would look for a converter that will flash to about 4,500 on the hit, in a 9" version. Yes, in the 383/406 bracket engines with 13.5 compression and a 227-230cc runner 23*, that Comp is what I use with 1.6 rockers. Works very well, and is offered off the shelf with a 4/7 swap and a .900 base circle. Very good cam. makes 700+ with it..
 

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Discussion Starter #15
New converter is 5200, Car's apart so ill find out asap, I might try that cam but always thought 108 LSA was not a good NOS cam
 

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What do you shift at normally with this engine as 5k off the bottle sounds real high for this hit for under 8000 rpm shift points. The 108 is fine, again I don't alter cams for nitrous unless more than 300 is used. What you gain with a wider lsa for the same hit, you will lose about double or more when run off the bottle. Cam it to run n/a. It will run very well with the 108. You will make more power with the Comp grind I recommended n/a and on the hit, and as a matter of fact may run faster on a smaller hit, which is better for relaibilty.
 

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I run a Lunati .679/.630 278/286 with a 108 LSA. It works fine on motor and has worked fine up to a 300hp shot of juice.
 
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