Ol 383 back on the rollers.
11-21-2018, 10:26 AM
#41
TECH Senior Member
Looks like Mast has a little side hustle going with their unported heads...
11-21-2018, 10:39 AM
#42
10 Second Club
11-21-2018, 10:40 AM
#44
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11-21-2018, 10:41 AM
#45
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11-21-2018, 01:19 PM
#46
TECH Senior Member
These are neat. They’re basically mast castings but not cnc’d. I think would be great on a 383
http://www.performance-world.com/Cyl...s-p/63240a.htm
http://www.performance-world.com/Cyl...s-p/63240a.htm
11-21-2018, 02:46 PM
#47
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11-21-2018, 03:03 PM
#48
TECH Senior Member
11-21-2018, 07:05 PM
#49
11 Second Club
Thread Starter
So say I went out & spent a couple grand & got a whole new top end for my engine. Same compression & custom cam spec'd very close to this one but for LS3 heads. Around same overlap. What power would it make then & at what rpm?
11-21-2018, 08:04 PM
#50
11-21-2018, 08:35 PM
#52
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Thread Starter
11-21-2018, 09:03 PM
#54
10 Second Club
11-21-2018, 09:25 PM
#55
Nice job Rick. He already knows a Mamo MSD with a bigger tb would be kickass but he said it might not clear the cowl on his car. Plus upgrading the intake track with a Dougy box/Pro stock MAF,bigger MAF.... but who cares about dyno numbers. I think the heads and cam are fine. Is there an Improved racing scraper for that block? That would help since that car makes it's shifts north of 7000. Make the car lighter(he has heavy wheels,suspension,full size battery) and with more gear it would really freaking fly in the 1/4 mile but that is not what this car is about...
Oh yeah, You know the bitching is coming..........E85!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!
Oh yeah, You know the bitching is coming..........E85!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!
11-30-2018, 02:03 PM
#56
11 Second Club
Thread Starter
Thanks Mike.
So just for fun I got the graph scaled on the 50hp as we usually do. Just to show the power does not drop as hard as the other graph skews. Actually my car's power does not seem to fall off at all up top. As I've noticed on a race vid. Where I expect to see my car fall off say after 6500rpm to 7100. It seems to pull strong, the strongest, up top until I shift.
I figured one thing that may have something to do with how it pulls like that & doesn't fall off as the power scale would imply. If you multiply the hp by the rpm it is at you get a number. My number peaking around 500rwhp at 6600rpm. The number is 3.3mil. Now multiplying anything after that all the way to 7200 rpm the number is right around the same 3.3mil. Is this a way to tell basically if it is an advantage or disadvantage to keep revving. Say if the number started getting below the 3.3mil that is when you will start to see the drop in performance?
Oh and the SAE number dropped 12hp to 492.
12-07-2018, 12:41 AM
#59
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Rick to answer your question, look at your torque curve and multiply by your gear ratios.
Look at torque at x RPM in first gear times first gear ratio. Then look at RPM where you land in second gear. Multiply that torque by second gear ratio. If total first gear torque is still higher than total second gear torque, you should stay in first.
With your power peaking at 6600, your shift point may be as high as 7600 rpm, land right on 5200, and ride the power curve.
There are people with your power curve who would shift at 6600 and lose 1000 ft lbs of actual rear tire torque on the upshift by the time you factor in transmission and rear gear ratios.
Look at torque at x RPM in first gear times first gear ratio. Then look at RPM where you land in second gear. Multiply that torque by second gear ratio. If total first gear torque is still higher than total second gear torque, you should stay in first.
With your power peaking at 6600, your shift point may be as high as 7600 rpm, land right on 5200, and ride the power curve.
There are people with your power curve who would shift at 6600 and lose 1000 ft lbs of actual rear tire torque on the upshift by the time you factor in transmission and rear gear ratios.
12-07-2018, 11:32 PM
#60
11 Second Club
Thread Starter
Rick to answer your question, look at your torque curve and multiply by your gear ratios.
Look at torque at x RPM in first gear times first gear ratio. Then look at RPM where you land in second gear. Multiply that torque by second gear ratio. If total first gear torque is still higher than total second gear torque, you should stay in first.
With your power peaking at 6600, your shift point may be as high as 7600 rpm, land right on 5200, and ride the power curve.
There are people with your power curve who would shift at 6600 and lose 1000 ft lbs of actual rear tire torque on the upshift by the time you factor in transmission and rear gear ratios.
Look at torque at x RPM in first gear times first gear ratio. Then look at RPM where you land in second gear. Multiply that torque by second gear ratio. If total first gear torque is still higher than total second gear torque, you should stay in first.
With your power peaking at 6600, your shift point may be as high as 7600 rpm, land right on 5200, and ride the power curve.
There are people with your power curve who would shift at 6600 and lose 1000 ft lbs of actual rear tire torque on the upshift by the time you factor in transmission and rear gear ratios.