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What was the DA of the track on that day? Have you run it on a chassis dyno or checked the AFR since putting it in the car? I was surprised to find that putting full exhaust and a very large paper air filter on my engine significantly changed the AFR and power.
 

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Discussion Starter #23
What was the DA of the track on that day? Have you run it on a chassis dyno or checked the AFR since putting it in the car? I was surprised to find that putting full exhaust and a very large paper air filter on my engine significantly changed the AFR and power.
DA was about 2303 on the first run and over 3000 on the last.

No chassis dyno yet. My afr was 12.3 - 12.8 throughout the first three runs.

I'm running a 14x3 K&N, I removed it on the last run and gave me the fastest mph with the highest DA of all the runs. I haven't checked the afr on that run yet though.
 

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I ask because your MPH is low. In 2014 I ran a 427SBC that made 640HP and 565 torque. In my 3,400 pound '69 Camaro it ran 10.41 at 128 with a 1.5193 sixty foot off the foot brake. This was before I put it on a chassis dyno and found that the 14" X 4" air filter cost 12RWHP and that the AFR was 12.0 now instead of 12.8 on the engine dyno. My combo picked up about 35RWHP but I didn't take it back to the track to see what it picked up. It was setup for nitrous so the ET on the motor wasn't as important. Your engine has a little more HP, even more torque and Nova's are typically lighter than first gen Camaro's, which is why I'm asking.
 

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I ask because your MPH is low. In 2014 I ran a 427SBC that made 640HP and 565 torque. In my 3,400 pound '69 Camaro it ran 10.41 at 128 with a 1.5193 sixty foot off the foot brake. This was before I put it on a chassis dyno and found that the 14" X 4" air filter cost 12RWHP and that the AFR was 12.0 now instead of 12.8 on the engine dyno. My combo picked up about 35RWHP but I didn't take it back to the track to see what it picked up. It was setup for nitrous so the ET on the motor wasn't as important. Your engine has a little more HP, even more torque and Nova's are typically lighter than first gen Camaro's, which is why I'm asking.
Fontana has a 28.8 baro, that area has horrible air, Sacramento has a 30 plus baro, and great air, that right there is the difference, major HP difference between the two tracks. My point is your not going to make HP in a 28.80 baro with a pypes exhaust system.




Sacramento:
temperature = 52.88 deg f
relative humidity = 56 %
uncorrected barometer* = 30.16 inHg
corrected barometer* = 30.24 inHg
wind speed = 7.57 mph
wind direction* = NW (334°)
more info: current metric | historical | forecast | help
dew point = 38 deg f
saturation pressure = 0.403 inHg
vapor pressure = 0.226 inHg
grains = 32.8
air density (w/o water vapor) = 102%
air density (w water vapor) = 101%
density altitude = -490.34 ft


Fontana:
temperature = 58.92 deg f
relative humidity = 28 %
uncorrected barometer* = 28.80 inHg
corrected barometer* = 30.00 inHg
wind speed = 5.42 mph
wind direction* = NE (67°)
more info: current metric | historical | forecast | help
dew point = 26 deg f
saturation pressure = 0.502 inHg
vapor pressure = 0.141 inHg
grains = 21.3
air density (w/o water vapor) = 96%
air density (w water vapor) = 96%
density altitude = 1390.24 ft


I guarantee there is 50 plus HP observed on the dyno between Fontana and Sacramento in these type of conditions. When the baro is over 29.92 you are super charging the NA engine for free.
 

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Good Going RENZO!
Thanks for sharing the vids and info!
 

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Wow. Great build.

I would like to know the weight. Any guesses.
 

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Wow. Great build.

I would like to know the weight. Any guesses.
I'm going to say 3500 with a big block.
Mine is 3300 and change with a SB, alum heads,rad,water pump, all steel,glass,interior and full exhaust to behind the tires.
 

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Wow. Great build.

I would like to know the weight. Any guesses.
I'm going to say 3500 with a big block.
Mine is 3300 and change with a SB, alum heads,rad,water pump, all steel,glass,interior and full exhaust to behind the tires.

I essentially have the same car as the OP. Mine does have a full chromoly cage and a Dana 60 instead of a 9". My car weighs 3515 with me in it.
 

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Discussion Starter #33
Planning on getting the car scaled, hopefully soon.

I didn't think the exhaust would be a bottleneck but definitely would like to confirmed if it is. Maybe it will be worth running open headers next time out.

While checking timing we noticed the throttle bracket had some noticeable flex, checked throttle and we were not getting full throttle (this was before the runs), made some adjustments to the throttle cable and was able to get more throttle but still not all the way. Lots of flexing from the bracket, pedal and even the firewall. Can a 7/8s throttle opening have an effect?

Pictures below show the difference between what i'm getting with the pedal to the floor and full throttle.
 

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What is your pedal/bracket/cable set up?

I use a stock pedal in my Nova with a lokar bracket and cable. I had to change the way the bracket was supported and how I was bolting it on in order to have it stay in place and give consistent throttle opening.

Replaced the small Allen head screw which pushes against the carb baseplate with a normal larger head stainless steel one, and lock it in place with 2 nuts. The large head of the screw pushes against the baseplate. And when installing the bracket it is pulled out as far as it can go to the drivers side so the carb stud is at the end of the slot in the bracket.
 

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Wow. Great build.

I would like to know the weight. Any guesses.
I'm going to say 3500 with a big block.
Mine is 3300 and change with a SB, alum heads,rad,water pump, all steel,glass,interior and full exhaust to behind the tires.

I essentially have the same car as the OP. Mine does have a full chromoly cage and a Dana 60 instead of a 9". My car weighs 3515 with me in it.
Wow that’s light with a big block and a cage.

So 3” exhaust and ultra flo straight through mufflers are restrictive?
I guess I should have dropped my exhaust when I went.
Mine was 3” reduced at the X pipe to 2.5” mufflers and tails....
I wanted to run my car the way it runs the streets and run 10’s like the OP.
Goal met for both of us on 1st trip to the track.
 

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Planning on getting the car scaled, hopefully soon.

I didn't think the exhaust would be a bottleneck but definitely would like to confirmed if it is. Maybe it will be worth running open headers next time out.

While checking timing we noticed the throttle bracket had some noticeable flex, checked throttle and we were not getting full throttle (this was before the runs), made some adjustments to the throttle cable and was able to get more throttle but still not all the way. Lots of flexing from the bracket, pedal and even the firewall. Can a 7/8s throttle opening have an effect?

Pictures below show the difference between what i'm getting with the pedal to the floor and full throttle.

The throttle opening wont have as much effect as one might think, I changed carpet in my car a few years ago and went to the track shortly after car ran great but felt a little soft 11.0`s @123 got home started checking for the issue found my throttle was only opening about 1/2 way hardly any secondary opening at all. I fixed the issue went back to the track in similar conditions ran 10.80`s @124-5 that was with half throttle...

Brian
 

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Discussion Starter #37
I have the lokar pedal and cable assy, the carb bracket is a Summitt aluminum piece. I did have to make a sharp turn off the firewall and cyl head with the cable. so im going to revisit that. Might end up fabricating my own bracket and then fix/strengthen the firewall (I think it might cracked).

Trying to sort every little detail out and knowing that i dont have full throttle bugs the crap out of me.
 

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Something I didn't see in the build link was any mention of the intake being worked over. I have talked to some people that feel the Roval shape of the AFR265s,290s,300s are best when an intake has been worked to take advantage. Did the air gap get worked over?
 

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Nice passes for the first trip out in crap DA.... Definitely 10.50s in good winter air....

I'm not surprised a bit from an MJ motor tho....
 

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Fontana has a 28.8 baro, that area has horrible air, Sacramento has a 30 plus baro, and great air, that right there is the difference, major HP difference between the two tracks. My point is your not going to make HP in a 28.80 baro with a pypes exhaust system.




Sacramento:
temperature = 52.88 deg f
relative humidity = 56 %
uncorrected barometer* = 30.16 inHg
corrected barometer* = 30.24 inHg
wind speed = 7.57 mph
wind direction* = NW (334°)
more info: current metric | historical | forecast | help
dew point = 38 deg f
saturation pressure = 0.403 inHg
vapor pressure = 0.226 inHg
grains = 32.8
air density (w/o water vapor) = 102%
air density (w water vapor) = 101%
density altitude = -490.34 ft


Fontana:
temperature = 58.92 deg f
relative humidity = 28 %
uncorrected barometer* = 28.80 inHg
corrected barometer* = 30.00 inHg
wind speed = 5.42 mph
wind direction* = NE (67°)
more info: current metric | historical | forecast | help
dew point = 26 deg f
saturation pressure = 0.502 inHg
vapor pressure = 0.141 inHg
grains = 21.3
air density (w/o water vapor) = 96%
air density (w water vapor) = 96%
density altitude = 1390.24 ft


I guarantee there is 50 plus HP observed on the dyno between Fontana and Sacramento in these type of conditions. When the baro is over 29.92 you are super charging the NA engine for free.






Hey Mark what did you not like about his exhaust system?
 
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