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Ordering Cam this week, which one?

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Old 02-12-2002, 01:35 PM
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Car: 1991 Firebird
Engine: 383 stroker
Transmission: T-56
Ordering Cam this week, which one?

Ok fellas, time to let your cam knowlegde shine. Here the deal, I'm swapping my LO3 out of my 91 Bird soon and dropping in a 350 non roller motor. It will have a Perfomer RPM intake with a 454 TBI on top, Vortec heads, flat top pistons , headers and a custom chip. Gonna also use the stock converter cause of cash issues. And will also be running the 2.73's cause of the same problem as noted above. I've pretty much narrowed it down to two cams. Comp's XE268H 268/280 .477/.480 with 110 degree lob sep. and a Compucam with 272/284 .454/.480 with 114 degree lob sep. Anybody ever used either one with a similiar setup, or have any suggestions? Thanks for any help.
Old 02-12-2002, 02:00 PM
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swap out those gears first! its going to be slower then hell unless you do.
Old 02-12-2002, 02:07 PM
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Car: 1991 Firebird
Engine: 383 stroker
Transmission: T-56
I'm not really looking for super fast launches or anything just yet. Plus I don't rubber anyway, only 255's. I'm looking for more get up and go on the highway
Old 02-12-2002, 06:07 PM
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Car: 2006 Silverado 1500
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my pick would be the xe268.
Old 02-12-2002, 07:17 PM
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Car: 99 Formula
Engine: LS1
Transmission: T56
Axle/Gears: 342
With those gears and stock TC wouldn't the 268 be a little too much. Of course it would be there for later. The power band starts @2k rpms. Then again, I guess with the steep first gear of the 700R4, you wouldn't see below 2k rpm for long.
Old 02-12-2002, 07:49 PM
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Car: 1986 Sport Coupé
Engine: 305-4v
Transmission: 700R4 and TransGo2
If you want to use that cam you are compelled to do head work. The Vortec's springs will need changing and the seats need machining to handle that extra lift. If you aren't into that then stick to an XE256, which will work just fine with the stock Vortecs.
Old 02-12-2002, 10:23 PM
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Car: 1991 Firebird
Engine: 383 stroker
Transmission: T-56
The 350 that I'm refering to came out of my boat including the vortec heads, I ran a Blazer cam with .465/488 with no problem, ***** to the wall half the time too.
Old 02-12-2002, 11:25 PM
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Uhhh....

Does the cam you are referring to have 206/210 degrees at .050" lift? If so, you will be happy with its performance. The powerband is good from idle-5500 rpm and the torque will work with your 2.77s and your stock stall - especially if those flat tops give you 9.5 - 10.5 compression The 276 is to friggin big and you will run like crap so dont think about it. For a compromise, I think the 266 would be the most you would want to run with 210/220 degrees at .050" lift. hope I was helpful
Old 02-13-2002, 12:03 AM
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Car: 1991 Firebird
Engine: 383 stroker
Transmission: T-56
The XE268 is 224/230 at .050". Comp says its the biggest cam that will work with a stock TC. So I was just going by that. Desktop Dyno show about 360 ft/lbs at 2000. Hoping that is enough for that converter.
Old 02-13-2002, 12:24 AM
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Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
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Axle/Gears: 7.5" Auburn 4.10 Posi-Traction
I'd use something smaller than the xe 268
You won't be in it's best power band most of the time.
Check your hwy cruise rpm (in "D") and use the Crane
Cruise rpm@60 mph guidelines to select the right cam range
after that , the brand name is up to you. The Extreme energy series cams may cause idleing problems with your TBI system.
http://www.cranecams.com.

Last edited by F-BIRD'88; 02-13-2002 at 12:27 AM.
Old 02-13-2002, 11:24 AM
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My bad...

I was referring to the 262 when I replied instead of the 268 - I guess I just got mixed up. IMHO dont go with anything bigger than the 266, while you will be happiest with a cam 1 or 2 sizes smaller - ESPECIALLY with weak 2.77s and NO stall
Old 02-13-2002, 11:30 PM
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Car: 1986 Sport Coupé
Engine: 305-4v
Transmission: 700R4 and TransGo2
Originally posted by Tom91Bird
The 350 that I'm refering to came out of my boat including the vortec heads, I ran a Blazer cam with .465/488 with no problem, ***** to the wall half the time too.
Not for very long will you run it like that! Your valve springs are going to lose their tension pretty quick. If you don't care that you are taking things beyond their specs, then by all means destroy your engine.
Old 02-14-2002, 02:54 AM
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Car: 86 Trans Am, 88 Formula
Engine: 95LT4, 305TPI
Transmission: T56, T5
I would suggest gears and higher stall converter.
My buddy has an 82 T/A with a cam that starts around 2K and it is very sluggish off the line. I've got the Compucam 2050 (which is now the PowerMax 2050) in my 86 Trans Am and since I have 3.23 gears and a 5 speed I can control how the car launches much better than a 2.73 geared car with stock stall converter.

Here is a vid of my car after the TPI, CAM, and exhaust upgrades.
http://www.donpagevideo.com/video/ZepherWS6.mpg
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