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81 Next mod please **Ideas**

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Old Feb 25, 2010 | 10:34 PM
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From: Escondido CA
Default 81 Next mod please **Ideas**

Headers, intake, cam done what next...

My engine is solid and after I get her smogged Im ripping all that junk off for emissions and putting it on the shelf for next time. I didnt go with a huge cam for smog reasons but I should be able to get into the high 300hp just fine.

What should I do next? Carb? Blower? Turbo? Gears? MSD?



Mods Done:
Weiand Intake Manifold
Headman Headers
Performer Rocker Arms
Dynomax Mufflers
Orig. Heads Rebuilt
Summit Racing Cam SUM-K1102
Cam and Lifters, Hydraulic Flat Tappet
Duration 262/272
Lift .420/.442
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Old Feb 25, 2010 | 11:13 PM
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What rearend gears do you have. A higher numerically gear might be the solution and you don't have to deal with the emissions
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Old Feb 25, 2010 | 11:19 PM
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Stock gears in here so far.
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Old Feb 26, 2010 | 03:47 AM
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700R4 Trans shift kit: cheap, DIY mod
Electric fans: realtively cheap, takes fan drag off motor: TQ adder

cool avatar - thats what its all about = driving
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Old Feb 26, 2010 | 06:30 AM
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Originally Posted by us marine
Stock gears in here so far.
a member of this Forum, who'd added vortec heads, cam, intake & carb, headers, etc., to his OEM 2.87:1-geared 1980 L-48, once drove my de-Cross-Fire'd '82 (original 26,000-mile long block, 650 Holley, aluminum intake), which I had swapped to 3.73s long ago:
I'd never driven his car (I'm in Floriduh, while he is still in Taxylvania), and afterwards, he said my car would smoke his in the 1/4-mile easily

I had tried to convince him that a gear change would greatly improve the performance of his car, but he recently sold the car:
we attribute my car's quicker acceleration with less HP simply to having deeper gears, and getting what-little power I have to the pavement more efficiently via same
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Old Feb 26, 2010 | 06:47 AM
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The trans. should be stated. If you have an auto., a higher lockup converter will help launch & still have highway rear gears.
Hi flow converter.
Heads.
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Old Feb 26, 2010 | 07:25 AM
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Originally Posted by us marine
What should I do next?
Drive the thing.
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Old Feb 26, 2010 | 08:08 AM
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Originally Posted by Glensgages
a member of this Forum, who'd added vortec heads, cam, intake & carb, headers, etc., to his OEM 2.87:1-geared 1980 L-48, once drove my de-Cross-Fire'd '82 (original 26,000-mile long block, 650 Holley, aluminum intake), which I had swapped to 3.73s long ago:
I'd never driven his car (I'm in Floriduh, while he is still in Taxylvania), and afterwards, he said my car would smoke his in the 1/4-mile easily

I had tried to convince him that a gear change would greatly improve the performance of his car, but he recently sold the car:
we attribute my car's quicker acceleration with less HP simply to having deeper gears, and getting what-little power I have to the pavement more efficiently via same
My slightly modified 82 crossfire crushes all my other cars off the line because of the gearing on the 700R4.
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Old Feb 26, 2010 | 01:51 PM
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This says 82 and above but will it work with my tranny still? Im thinking of 373 gears and a posi lock. What will fit my 81?

http://cgi.ebay.com/ebaymotors/700r4...Q5fAccessories

And

http://cgi.ebay.com/ebaymotors/GM-14...item2557bffd19
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Old Feb 26, 2010 | 02:04 PM
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i changed the rear stock gear to a 3.54 big change and drive it

And better heads. the smogs heads are the achilles tendon of the L-81
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Old Feb 26, 2010 | 02:10 PM
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Yeah im driving it right now. Off the line is slow as heck but if I punch in when in 2nd or 3rd it gets up and goes. Im sure a better gear ration will give me that tire squeeling I need to HEAR... ; ) So is there a big difference between 3:54 and 3:73 I mean is it noticable?

Maybe I can go to the 3:54 and keep some sort of gass milage.. How is yours?
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Old Feb 26, 2010 | 03:13 PM
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gas milage is great. it is the best of both worlds great off the line and not bad for long cruise.
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Old Feb 26, 2010 | 04:36 PM
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How may miles do you have on that bad blue boy, it might be time for a rearend rebuild and then you can go with graphite clutches. I have 3.73s with graphite clutches but everything else has been changed so don't go by me. but I can light up both of my 295-35s (that almost 2ft of tire width)

Last edited by captl27; Feb 26, 2010 at 04:38 PM.
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Old Feb 26, 2010 | 04:39 PM
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Carfax says 36,000 miles but Im not sure its accurate. Im leaning to buying a 700r with shift kit and posi lock and calling it a day. Hmmm
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Old Feb 26, 2010 | 04:42 PM
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Its all good. As long as its C3
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Old Feb 26, 2010 | 11:56 PM
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81 stock gears are 290s
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Old Feb 27, 2010 | 12:04 AM
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How did you select what mods you could make and still pass CA smog test? I have a 1980 that I may be doing some work on in the near future. Any input greatly appreciated.

JT
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Old Feb 27, 2010 | 12:06 AM
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Sorry, Leatherneck, but ain't no way you're getting a stock '81 long block into the high 300hp range. It just ain't happening. Now, you can feel like you have 300hp with the gear change, but on the motor, there's just not enough there.
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