Changing From A 350 To A 454 :)
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From: Clymer PA
Changing From A 350 To A 454 :)
My current goal is 500 + horsepower. I have my cam choice narrowed down to two cams (both are solid lifter cams):
Comp Cams Magnum 282S ; 2000-6000RPMs, .561" Lift, 110 Lobe Seperation
* Excellent For Street Machines ; Headers, 2500+ Stall, 9:1 CR, Lower Gears. Has A Rough Idle.
Comp Cams Magnum 294S ; 2500-6500RPMs, .595" Lift, 110 Lobe Seperation
*Good For Street/Strip Cars ; 3000+ Stall or 4 Speed, 10:1 CR, Headers, Lower Gears. Very Rough Idle.
I will only be using the stock cast crank with forged rods and hyperuetectic pistons....will the engine handle 6500RPMs. I was told that a well built big block should handle 6000RPMs with very little trouble. My setup is listed in my signature, which cam do you think would best suit my setup?
[Modified by bence13_33, 11:51 AM 10/20/2001]
Comp Cams Magnum 282S ; 2000-6000RPMs, .561" Lift, 110 Lobe Seperation
* Excellent For Street Machines ; Headers, 2500+ Stall, 9:1 CR, Lower Gears. Has A Rough Idle.
Comp Cams Magnum 294S ; 2500-6500RPMs, .595" Lift, 110 Lobe Seperation
*Good For Street/Strip Cars ; 3000+ Stall or 4 Speed, 10:1 CR, Headers, Lower Gears. Very Rough Idle.
I will only be using the stock cast crank with forged rods and hyperuetectic pistons....will the engine handle 6500RPMs. I was told that a well built big block should handle 6000RPMs with very little trouble. My setup is listed in my signature, which cam do you think would best suit my setup?
[Modified by bence13_33, 11:51 AM 10/20/2001]
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From: Clymer PA
Re: Changing From A 350 To A 454 :) (Vetteboy)
I have a 4 speed. The duration of the cams are:
Comp Cams Magnum 282S - Advertised:282 , @ .050:236
Comp Cams Magnum 294S - Advertised:294 , @ .050:248
The RPM range on the 282S is 2000-6000RPMs and the RPM range on the 294S is 2500-6500RPMs. I plan on revving the big block to 6500RPMs. The 3.70 gears and my wide ratio 4 speed will help out with my bottom end.
Comp Cams Magnum 282S - Advertised:282 , @ .050:236
Comp Cams Magnum 294S - Advertised:294 , @ .050:248
The RPM range on the 282S is 2000-6000RPMs and the RPM range on the 294S is 2500-6500RPMs. I plan on revving the big block to 6500RPMs. The 3.70 gears and my wide ratio 4 speed will help out with my bottom end.
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Re: Changing From A 350 To A 454 :) (bence13_33)
If those are THE two choices, I'd probably go for the 294S. Solids require a little more duration to compare with a hydraulic due to the motion lost with taking up the lash as it opens. In other words, a solid will "act" a little smaller than a comparable hydraulic.
The added duration I assume also has a little more overlap that will help control detonation at lower speeds. Your 3.70's will also help.
I suspect the actual peak power will hit in the mid-high 5000 range especially with that intake.
6500 rpm with oval ports on a 454 is out there. My 427 was happy in the 6200-6400 range at best. It would rev higher but there wasn't a lot of use. I ran MANY different solid flat tappets and rollers in it over a 20 year period.
Look at the specs closely. Are these split duration cams or symetrical? A little more duration on the exhaust side will really help when capped up. Comp usually makes their cams the same on centerlines and end up with equal centerlines on both in. and ex. as opposed to GM that will run a 116 or so on exhaust and a 110 on intake to get a 113 LSA. it makes a difference "How" you get the LSA.
110 is a good number for you. A 108 will sound tougher but will probably have too much overlap for your compression.
The last solid flat tappet I had in it was the Comp 294B. It has like 579/605 lift and 248/256 on 108 LSA. I think I'm pretty close on the specs from memory, but anyway, it sounded tough but in reality was slower than most of the others I ran over the years.
I had great luck with the old Crane series of solids. I see they are back in the Jegs catalog. The strongest was the 600/620 with 310/320 adv. on 110 LSA. It's pretty choppy but pulls hard.
The overall best was the 580/600 with 290/300 adv. on 110 LSA. It was almost as strong but was much more streetable. I believe it's in the 250 or so range a .050. This cam kills the Comp 294 B.
The 567/590 with 314/324 adv duration was OK, but not as good as the above two.
The Comp 306 and 310 magnums make tons of top end but are pretty soggy down low in a combo like yours.
If you can swing a roller, the 288AR street roller is a great street cam. 244 @.050 and makes strong power. By far the best street cam I ever tried in the 427. Crane makes one a little harrier 296/306 and 615/636 but it may be a little much for your setup.
Hope this helps a little,
Jim
The added duration I assume also has a little more overlap that will help control detonation at lower speeds. Your 3.70's will also help.
I suspect the actual peak power will hit in the mid-high 5000 range especially with that intake.
6500 rpm with oval ports on a 454 is out there. My 427 was happy in the 6200-6400 range at best. It would rev higher but there wasn't a lot of use. I ran MANY different solid flat tappets and rollers in it over a 20 year period.
Look at the specs closely. Are these split duration cams or symetrical? A little more duration on the exhaust side will really help when capped up. Comp usually makes their cams the same on centerlines and end up with equal centerlines on both in. and ex. as opposed to GM that will run a 116 or so on exhaust and a 110 on intake to get a 113 LSA. it makes a difference "How" you get the LSA.
110 is a good number for you. A 108 will sound tougher but will probably have too much overlap for your compression.
The last solid flat tappet I had in it was the Comp 294B. It has like 579/605 lift and 248/256 on 108 LSA. I think I'm pretty close on the specs from memory, but anyway, it sounded tough but in reality was slower than most of the others I ran over the years.
I had great luck with the old Crane series of solids. I see they are back in the Jegs catalog. The strongest was the 600/620 with 310/320 adv. on 110 LSA. It's pretty choppy but pulls hard.
The overall best was the 580/600 with 290/300 adv. on 110 LSA. It was almost as strong but was much more streetable. I believe it's in the 250 or so range a .050. This cam kills the Comp 294 B.
The 567/590 with 314/324 adv duration was OK, but not as good as the above two.
The Comp 306 and 310 magnums make tons of top end but are pretty soggy down low in a combo like yours.
If you can swing a roller, the 288AR street roller is a great street cam. 244 @.050 and makes strong power. By far the best street cam I ever tried in the 427. Crane makes one a little harrier 296/306 and 615/636 but it may be a little much for your setup.
Hope this helps a little,
Jim
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Re: Changing From A 350 To A 454 :) (427Hotrod)
Bence13_33: This is a little off topic but I would seriously condider a forged crank, particulary if you plan on spinning the motor to 6500 rpm. What type of rods are you using. I am a big believer in over building the botom end, if it goes so does a huge portion of you investment.
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From: Clymer PA
Re: Changing From A 350 To A 454 :) (69 N.O.X. RATT)
69 N.O.X. RATT:
I'm going to be using the '73 LS4 454 Forged Cast Rods with ARP Hi-Performance Rod Bolts. I will also be using the ARP Main Stud Kit. Once I have the engine completely broken in, I'll give it a run up to 6000 RPMs and see how it handles is. If it feels like it can go up higher, I'll take it up a bit higher. The highest that I plan on taking it is 6500, I was told that the crank and rods should handle those kind of RPMs with very little trouble.
Once I get the engine built, I'm going to take it and have it balanced.
I'm going to be using the '73 LS4 454 Forged Cast Rods with ARP Hi-Performance Rod Bolts. I will also be using the ARP Main Stud Kit. Once I have the engine completely broken in, I'll give it a run up to 6000 RPMs and see how it handles is. If it feels like it can go up higher, I'll take it up a bit higher. The highest that I plan on taking it is 6500, I was told that the crank and rods should handle those kind of RPMs with very little trouble.
Once I get the engine built, I'm going to take it and have it balanced.
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Joined: Aug 2000
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From: Clymer PA
Re: Changing From A 350 To A 454 :) (Cam Potter)
Cam:
By "reciprocating mass" I take it you mean the flywheel and harmonic dampner? I had no idea it was done before assembly (learn something new everyday). Thanks for the information :cool:
By "reciprocating mass" I take it you mean the flywheel and harmonic dampner? I had no idea it was done before assembly (learn something new everyday). Thanks for the information :cool:
