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Discussion Starter #1
How many passes did it take for your et to get back on track? I freshend my engine and made 1.5 8th mile passes so far but my ET is about almost 2 tenths off and I thought it was due to the fact that I didnt degree my cam in (stuck the brand new cam in where I took the old one out at) so I got it degreed in and the guy said it was right on time. He said it probably isnt running the same time it did before it was freshend because the engine is still tight and hasnt fully loosened up yet(bearings and piston ring seating). Is this possible or should this engine run the same time fresh off the engine stand? My mph was off by 1mph my ET was off by .17. My 60 foot was off by .05.

This is a N/A combo
 

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I don't see how you guys are saying a run is off .17. I get more then that difference between each run. Is it the same cam or different one?
 

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Senior phuckstick
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I've gone out after a rebuild and 20 mins run time in the garage, and run very consistant all season long.
The thing that seems to affect my times are usually the weather.
 

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Discussion Starter #5
Its the same cam, but they changed a few things on the new version of the same cam. Intake duration went from 270 to 275 @.50, intake timing events went from 27 open - 63 close, to 29.5 open to 65.5 close.

Valve lash went from .20 intake - .29 exhaust to .28 intake to .30 exhaust
 

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Discussion Starter #7
Well that's shitty. I'm going to get it dyno tuned again. I spent a lot of time and money getting where I had the car running.....
 

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F.T.W. KILL EM ALL
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Remember one very important thing.....You should only change ONE THING @ a time. It probably has to do with the few changes that you made (Possibly).
 

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out of work hair dresser
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Its the same cam, but they changed a few things on the new version of the same cam. Intake duration went from 270 to 275 @.50, intake timing events went from 27 open - 63 close, to 29.5 open to 65.5 close.

Valve lash went from .20 intake - .29 exhaust to .28 intake to .30 exhaust
That is FAR from the "same cam". It's a totally different cam and one of which you are going to have to hunt the tune to reap it's benefits if their are any.

Dyno tuning is great....................for the dyno...........but it does nothing for you at the track. Tune it at the track.
 

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Discussion Starter #13
I went out sunday to make a couple test hits and she is still off. I called Bullet Racing cams today and they said the higher duration should decrease my bottom end and give me more on the top end. They also said that I could pull out my new cam and send them my old and new cam card and they can regrind my cam back to how the old one was for 75 dollars, but im not sure if I feel like the headache of pulling this thing apart again. Any suggestion??? I have a vid of how the car used to launch and how it launches not.
http://www.youtube.com/watch?v=vq4k0nDbPbM Old Cam

http://www.youtube.com/watch?v=E7KrWIziZl8&feature=player_embedded New Cam

I also have 1.8 rockers on this thing instead of 1.7. (engine builder built it this way)
 

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Discussion Starter #17
I had 2 bad lifters and they wiped the cam so I sent my old cam in to get it fixed and they sent me the so call new and improved version of the cam. I'm gonna pull the cam out and get it grinded to the specs of my original cam. I used to have a wheelstanding issue with the car that I resently tamed by adjusting the limiters but now I can barely get the tires off the ground.
 

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Discussion Starter #18
During dyno tuning last year she stop making horsepower at 6400rpm. I read somewhere online that said if you don't have a high rpm engine longer durations will kill ya. I'm not sure if 6400 is considered to be high or low. I'm shifting at 6500
 

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There are so many varibles when a motor gets freshened up it can slow down real easy. Say you had good heads and they were done well. You get the motor feshened up and someone does a bad job grinding the valves. That alone can kill the power. Hone the block with the wrong stones or don't use torque plates or gap the rings right all rob power. If bearings are clearanced right and the hone job and rings are correctly done when you run the motor in and set the timing it should be ready to race unless it is some street type high endurance motor that was built intentionally tight.
 
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