65 Performance
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From: Suisun Ca
65 Performance
What adjustments or Modifications would be best for performance, lately it's not running as good as it should one example when running it idles halfway decent but doesnt rev, any suggestion are greatly appreciated
[Modified by Vougesmokr, 2:45 AM 6/8/2004]
[Modified by Vougesmokr, 2:45 AM 6/8/2004]
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Re: 65 Performance (Vougesmokr)
What engine? Is is stock or modified? What diagnostics have been done lately? Compression check? Thorough igntion system check out? Carburetor idle speed and mixture adjustment?
As a general rule, the closer these engines are to original OE specification the better they run.
Duke
As a general rule, the closer these engines are to original OE specification the better they run.
Duke
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Re: 65 Performance (Vougesmokr)
Well, before trying to upgrade performance, I would try and get the motor in tune.
My guess from the limited info is that it may be a carb issue, or points.
What engine do you have?
What HP rating?
Any mods from stock?
Type Carp?
Type Dist.?
How long since last service of points, plugs, wires, filters,
What is the Vacuum at idle?
Mark
My guess from the limited info is that it may be a carb issue, or points.
What engine do you have?
What HP rating?
Any mods from stock?
Type Carp?
Type Dist.?
How long since last service of points, plugs, wires, filters,
What is the Vacuum at idle?
Mark
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From: Suisun Ca
Re: 65 Performance (ghostrider20)
327 ; 365 hp, Modifications are HEI,Performer RPM Intake, Roller Tip Rockers, it has a Holly 600cfm double pumper, the vacum at idle fluctuates between 14 and 15. and I have done a compression test, 115 on all cyclinders & i set the timming
at 8 degrees BTC
at 8 degrees BTC
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Re: 65 Performance (Vougesmokr)
If if pulls 14-15" Hg. at idle it likely does not have the OE 30-30 cam, which only pulls about 10" at 900.
Sounds like this engine has been significantly modified from OE spec. Compression is low - should be about 150, but you can never tell about the absolute accuracy of compession gages.
The recommended initial timing range for the 327/365 is 10-14 degrees.
Duke
Sounds like this engine has been significantly modified from OE spec. Compression is low - should be about 150, but you can never tell about the absolute accuracy of compession gages.
The recommended initial timing range for the 327/365 is 10-14 degrees.
Duke
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From: Suisun Ca
Re: 65 Performance (SWCDuke)
does the fact that the engine was cold when i did the compression test make any difference?
as for performance I should been more specific , it's main problem is the enging doesnt make any power under load
as for performance I should been more specific , it's main problem is the enging doesnt make any power under load
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Re: 65 Performance (wildman378)
Quote
does the fact that the engine was cold when i did the compression test make any difference?
as for performance I should been more specific , it's main problem is the enging doesnt make any power under load
I have a stock 327/365 motor. The compression on my motor ranged from 180-185.
Compression tests should be done with all the plugs out, a battery charger hooked up to the car and the carb throttles positioned open. Wait between cylinder check until the battery batter has returned to full charge.
I doubt you have the 30-30 cam with those vacuum readings. What RPM are the vacuum readings taken at?
At 900 RPM I get 10” to 12” of HG at idle, and it is fluctuating.
If you have the 30-30 cam, the intake you have may be hurting the toad like qualities of the 30-30 below 2500 RPM.
What rear end gears do you have?
I have found very few applications that can utilize a double pump carb on the street, have you tried a single pump carb?
Mark
does the fact that the engine was cold when i did the compression test make any difference?
as for performance I should been more specific , it's main problem is the enging doesnt make any power under load
I have a stock 327/365 motor. The compression on my motor ranged from 180-185.
Compression tests should be done with all the plugs out, a battery charger hooked up to the car and the carb throttles positioned open. Wait between cylinder check until the battery batter has returned to full charge.
I doubt you have the 30-30 cam with those vacuum readings. What RPM are the vacuum readings taken at?
At 900 RPM I get 10” to 12” of HG at idle, and it is fluctuating.
If you have the 30-30 cam, the intake you have may be hurting the toad like qualities of the 30-30 below 2500 RPM.
What rear end gears do you have?
I have found very few applications that can utilize a double pump carb on the street, have you tried a single pump carb?
Mark
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Re: 65 Performance (ghostrider20)
Yes, compression tests should be made with the engine at operating temperature, in addition to the other issues discussed by Mark.
The 327/365 is torque shy, but VERY strong on top.
You need to be more specific about the problems you are experiencing - "does not make power under load" isn't very descriptive.
You should consider taking it to a good dyno tune guy. Run it at load while looking at timing and F/A ratio. Your engine sounds like "Heinz 57", and it could be some "tuning" issues that need to be addressed.
Redo the compression test hot, throttle wide open, all plugs out, good battery with a charger hooked up, and get a new set of numbers. If the compression is good, it's probably a tuning issue which is difficult to isolate without equipment, and a good dyno guy should be able to find and correct the problem.
Duke
The 327/365 is torque shy, but VERY strong on top.
You need to be more specific about the problems you are experiencing - "does not make power under load" isn't very descriptive.
You should consider taking it to a good dyno tune guy. Run it at load while looking at timing and F/A ratio. Your engine sounds like "Heinz 57", and it could be some "tuning" issues that need to be addressed.
Redo the compression test hot, throttle wide open, all plugs out, good battery with a charger hooked up, and get a new set of numbers. If the compression is good, it's probably a tuning issue which is difficult to isolate without equipment, and a good dyno guy should be able to find and correct the problem.
Duke
