Dennis
Engine rebuild/conversion
Thread Starter
Instructor
Joined: Jan 2015
Posts: 241
Likes: 9
From: Lynchburg VA
Engine rebuild/conversion
1961 NOM 283 2x4bbl 245hp 3756519 Block is date coded L61 (Dec 61)
The motor is represented and assembly stamped as a 283 245hp. I haven't gotten into the motor just yet and because of the date code it could possibly be a 327? But anyway, I am considering switching to the Duntov cam and improved lifters (270hp conversion) along with a valve train upgrade and timing chain upgrade when I do the rebuild. Question is: What are the proper part numbers or specs for the cam and lifters?
Anything else you can add is appreciated as well!
Thanks!
The motor is represented and assembly stamped as a 283 245hp. I haven't gotten into the motor just yet and because of the date code it could possibly be a 327? But anyway, I am considering switching to the Duntov cam and improved lifters (270hp conversion) along with a valve train upgrade and timing chain upgrade when I do the rebuild. Question is: What are the proper part numbers or specs for the cam and lifters?
Anything else you can add is appreciated as well!
Thanks!
Last edited by ByByeAmericanPie; Nov 8, 2015 at 10:40 PM.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 241
Likes: 9
From: Lynchburg VA
Has anyone had any experience with converting a 245hp x 2 4bbl setup to the 270hp setup by installing the 30-30 cam? Besides maybe converting to solid lifters, are there any other things I should upgrade/convert in the process?
It seems that the original 270hp had hydraulic lifters from the factory but many of the advertised "30-30" cams come with solid lifters. The one I had been looking at is the Predator cam. The advertised specs are:
INTAKE/EXHAUST
DURATION @.050 254/254
LOBE LIFT .323/.323
LOBE SEPARATION 110/118
SEAT DURATION AT 314/314
GROSS VALVE LIFT .485/.485
VALVE LASH ( HOT) .030/.030
Are there better ones out there that anyone has tried?
It seems that the original 270hp had hydraulic lifters from the factory but many of the advertised "30-30" cams come with solid lifters. The one I had been looking at is the Predator cam. The advertised specs are:
INTAKE/EXHAUST
DURATION @.050 254/254
LOBE LIFT .323/.323
LOBE SEPARATION 110/118
SEAT DURATION AT 314/314
GROSS VALVE LIFT .485/.485
VALVE LASH ( HOT) .030/.030
Are there better ones out there that anyone has tried?
Race Director
Joined: Feb 2007
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From: northern california
C2 of Year Finalist (track prepared) 2019
Has anyone had any experience with converting a 245hp x 2 4bbl setup to the 270hp setup by installing the 30-30 cam? Besides maybe converting to solid lifters, are there any other things I should upgrade/convert in the process?
It seems that the original 270hp had hydraulic lifters from the factory but many of the advertised "30-30" cams come with solid lifters. The one I had been looking at is the Predator cam. The advertised specs are:
It seems that the original 270hp had hydraulic lifters from the factory but many of the advertised "30-30" cams come with solid lifters. The one I had been looking at is the Predator cam. The advertised specs are:
I don't know anyone who has put a 30-30 cam in a 283. I'm sure it can be done, but my instinct is that you wouldn't be happy with it.
Jim
Thread Starter
Instructor
Joined: Jan 2015
Posts: 241
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From: Lynchburg VA
270 HP engine came with the Duntov 097 cam. An exact replacement for that cam is available at your FLAPS as Federal Mogul/Speed Pro CS113R. Like the original Duntov 097, this is a solid lifter cam for which your FLAPS can provide lifters.
I don't know anyone who has put a 30-30 cam in a 283. I'm sure it can be done, but my instinct is that you wouldn't be happy with it.
Jim
I don't know anyone who has put a 30-30 cam in a 283. I'm sure it can be done, but my instinct is that you wouldn't be happy with it.
Jim
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Thread Starter
Instructor
Joined: Jan 2015
Posts: 241
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From: Lynchburg VA
These is what I found on Summit:
Cam: http://www.summitracing.com/parts/slp-cs-113r
Lifters: http://www.summitracing.com/parts/slp-at-992
Cam: http://www.summitracing.com/parts/slp-cs-113r
Lifters: http://www.summitracing.com/parts/slp-at-992
Burning Brakes
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From: Plymouth MN
Finalist 2022 C1 of the Year - Unmodified
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Here is my build thread from a few years ago. This 283 build resulted in a car with nice manners - and very respectable performance.
I hope this helps you. And please accept my apologies if you have seen this thread before.
Kevin
Here is my build thread from a few years ago. This 283 build resulted in a car with nice manners - and very respectable performance.
I hope this helps you. And please accept my apologies if you have seen this thread before.
Kevin
Le Mans Master
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From: Las Vegas - Just stop perpetuating myths please.
It just reads like u have your mind set on this Duntov Cam whether its the right/best cam or not. The way to choose a cam is first measure your static compression using a piece of plexiglass and a graduated cylinder for both the piston volume and head chamber then u can chose a cam to optimize your compression and combination. What im saying is the cam is least expensive part that u can buy to optimize to make all your engine parts - heads, cubic inches, compression - make the most power/performance. Think about it. How expensive is it to buy heads to match your pistons/compression/heads/cam/intake/exh? Or install pistons to make a cam and heads work with your intake & exh?
What im saying is just hoping someone has used that cam in your similar engine with good results is going to be as good as buying a cam to match your engine is not optimizing what u have. It will only give u partial success. Custom cam grinds are only another $30 these days.
What im saying is just hoping someone has used that cam in your similar engine with good results is going to be as good as buying a cam to match your engine is not optimizing what u have. It will only give u partial success. Custom cam grinds are only another $30 these days.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 241
Likes: 9
From: Lynchburg VA
It just reads like u have your mind set on this Duntov Cam whether its the right/best cam or not. The way to choose a cam is first measure your static compression using a piece of plexiglass and a graduated cylinder for both the piston volume and head chamber then u can chose a cam to optimize your compression and combination. What im saying is the cam is least expensive part that u can buy to optimize to make all your engine parts - heads, cubic inches, compression - make the most power/performance. Think about it. How expensive is it to buy heads to match your pistons/compression/heads/cam/intake/exh? Or install pistons to make a cam and heads work with your intake & exh?
What im saying is just hoping someone has used that cam in your similar engine with good results is going to be as good as buying a cam to match your engine is not optimizing what u have. It will only give u partial success. Custom cam grinds are only another $30 these days.
What im saying is just hoping someone has used that cam in your similar engine with good results is going to be as good as buying a cam to match your engine is not optimizing what u have. It will only give u partial success. Custom cam grinds are only another $30 these days.