Please help me with 350 questions!
dustinlmiller13
03-02-2006, 11:13 PM
I tried to get help on the Camaro forum, but no one would help. I have a 1980 Camaro, with a stock 74 model 350 engine. I just recently purchased a set of 291 double hump castings, dynomax 1 5/8 primaries w/ 3 inch collector, Pro Stock cam .224 int and .224 exh @ .050 ([email protected]) w/ .450 .460 valve lift, Purple Hornies 3 inch inlet w 2 1/4 outlet glasspacks and turndowns, complete gasket set, Holley double pumper 650cfm, Edelbrock Performer manifold. Now, will this be enough to push me to 300 horses? Can I run with my buddies 1998 bone stock except for chip, flowmaster LS1 Camaro? Thanks for any ideas or suggestions. Please help!
dustinlmiller13
03-02-2006, 11:18 PM
Oh, I almost forgot. The 291 Heads came off of a 327 Corvette, they have 194 intake and 150 exhaust, they are set up to take the cam with tougher springs. Will I be able to run with 93 octane gas cause the heads have 63cc chambers? The reason for all of this is my buddie is the top dog around here (real small hick town in Tennessee) and I am running him for money at Bristol Motor Speedway.
MrPbody
03-03-2006, 08:34 AM
To answer your specific questtion, no. It will take a lot more than 300 horsepower from that early small block to run with the modern car.
Dump the double-hump heads! They were obsolete in 1969. I know, this goes against all of the shadetree and backyard racers' opinions. So be it. They (327 heads) work well on smaller engines (327s...). 041 (last three digits of the later "good" head) is a superior design, and was released late in '68. It too, has the 64 CC chamber (advertised). It has larger intake runners and a bit better chamber shape.
You will need a chamber size in the 70-72 CC range to use 93 octane with a 355, with flat-top pistons. Your ratio now will require mixing race gas with 93 to ward off detonation. The casting considered the "best large chamber" head is 441 (production, that is). It has the same runner volume as 041, with a 76 CC chamber. It's good enough, NASCAR banned it in the lower level engines, as it offered "an unfair advantage over those that cannot locate these castings" (getting tough to find).
You're also going to need a lot "more" camshaft. I would recommend a specific grind if you would tell me your gear ratio, weight of the car, and type of performance driving you intend to do (drag race? Street? etc...).
I would suggest Performer RPM "Air Gap" if your budget can stand it. Most of the parts you've listed are "aimed" at a low-end/mid-range engine, that will run out of "breath" around the 5,500 RPM mark. The power it will take to run down an LSx powered car, comes from revving the small block. They're not famous for torque down low. They're famous for revving to the moon and staying alive. Use the strong points of the engine. The 650 carb will be fine up to 7,000.
All is not lost. Those 291s are popular among the restoration crowd these days. You should have no trouble getting your money out of them. I would suggest you sell them, and use the proceeds to get a pair of Iron Eagles or World S/Rs. Out of the box, either of these heads are superior to the aforementioned 041s.
We (CVMS) have many effective packages for small block Chevy. I'll be happy to supply a parts list if you define your requirements as closely as possible.
Jim
Dump the double-hump heads! They were obsolete in 1969. I know, this goes against all of the shadetree and backyard racers' opinions. So be it. They (327 heads) work well on smaller engines (327s...). 041 (last three digits of the later "good" head) is a superior design, and was released late in '68. It too, has the 64 CC chamber (advertised). It has larger intake runners and a bit better chamber shape.
You will need a chamber size in the 70-72 CC range to use 93 octane with a 355, with flat-top pistons. Your ratio now will require mixing race gas with 93 to ward off detonation. The casting considered the "best large chamber" head is 441 (production, that is). It has the same runner volume as 041, with a 76 CC chamber. It's good enough, NASCAR banned it in the lower level engines, as it offered "an unfair advantage over those that cannot locate these castings" (getting tough to find).
You're also going to need a lot "more" camshaft. I would recommend a specific grind if you would tell me your gear ratio, weight of the car, and type of performance driving you intend to do (drag race? Street? etc...).
I would suggest Performer RPM "Air Gap" if your budget can stand it. Most of the parts you've listed are "aimed" at a low-end/mid-range engine, that will run out of "breath" around the 5,500 RPM mark. The power it will take to run down an LSx powered car, comes from revving the small block. They're not famous for torque down low. They're famous for revving to the moon and staying alive. Use the strong points of the engine. The 650 carb will be fine up to 7,000.
All is not lost. Those 291s are popular among the restoration crowd these days. You should have no trouble getting your money out of them. I would suggest you sell them, and use the proceeds to get a pair of Iron Eagles or World S/Rs. Out of the box, either of these heads are superior to the aforementioned 041s.
We (CVMS) have many effective packages for small block Chevy. I'll be happy to supply a parts list if you define your requirements as closely as possible.
Jim
dustinlmiller13
03-04-2006, 10:17 PM
Hey man, thanks for the info! My only prob is that I cant afford to go with a higher priced head. I am trying now to save up to get a set of 410 gears put into the rear and then rebuilding the tranny. I think I might take him though seeing as how his has 144k miles on it and it smokes. Ill see if he wants to race for fun first like on pinks, ha ha.
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