1977 350 Performance
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Joined: Apr 2008
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1977 350 Performance
I just picked up a 77 L82 Vette. She is one sweet ride, but she is bone stock and a little slow for my liking!
What are some common mods that will boost the power in this vette for a good value. Best return on investment for a smaller budget? Cam, intake, etc?
Thanks
What are some common mods that will boost the power in this vette for a good value. Best return on investment for a smaller budget? Cam, intake, etc?
Thanks
Race Director
Joined: Apr 2007
Posts: 14,062
Likes: 602
From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
If I were to do it all over again. I would get the zz4 and do the lt4 hot cam package on the car before i installed it.. with that cam and a little porting of the zz4 heads you can easly be over the 300 mark.....
so pull that # matching motor and save it.. ill be rebuilding my #matching motor and just setting it to the side......good luck
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Advanced
Joined: Apr 2008
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Will an LS1 out of a C5 bolt right up to the tranny on these? How much power will this tranny hold safely without bulletproofing?
Racer
Joined: Feb 2009
Posts: 495
Likes: 5
From: Lexington KY
Burning Brakes
Joined: Dec 2005
Posts: 992
Likes: 56
From: Baldwinsville, NY
Whats your budget?
Recurve the distributor; get the carburetor redone and a good tune up.
Dual exhaust if the law permits it where you live.
A cam and intake is only for show, you need more compression and heads before a cam and intake.
I should have gone for the ZZ4, but for now I will hide behind that old saying, “I was on a budget”.
Dual exhaust if the law permits it where you live.
A cam and intake is only for show, you need more compression and heads before a cam and intake.
I should have gone for the ZZ4, but for now I will hide behind that old saying, “I was on a budget”.
Safety Car
Joined: Jan 2009
Posts: 3,736
Likes: 56
From: anchorage ak
crate motors are the way to go if youre not the type to get the satisfaction from a job well done ( or job gone horribley bad) lol. schafiroff, cnc-motorsports, gm performance all good companies to do bussines with & the only limitations are you bank account. but if your looking to get a few more horse's out of what you have, first do a compression test, to verify that you still have decent compression as not to through good parts at a fading bottom end. with the right heads, camshaft, intake & headers with true dual exhaust it's fairly easy to get 400 horse all by 5800 rpm. the two bolt bottom end will sustain 5800 rpm. afr's web site has dyno'd combo's for small block chevy. just my 1.5 cent's.
Pro
Joined: Apr 2008
Posts: 596
Likes: 6
From: Irving Texas
If you're like me and have a limited budget after a Vette purchase:
Free: advance the timing at the distributor, set the idle as low as possible without dying
$100s: full length headers, 2 1/2 exhaust and high flow cats if needed, rebuild carb, new coil, dist cap and wires
$1000s: aftermarket heads
In that order!
Or do what my buddy did and put it all on a credit card:
Free: advance the timing at the distributor, set the idle as low as possible without dying
$100s: full length headers, 2 1/2 exhaust and high flow cats if needed, rebuild carb, new coil, dist cap and wires
$1000s: aftermarket heads
In that order!
Or do what my buddy did and put it all on a credit card:
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Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
start with a real tune up and make sure everything is working correctly especially with the distributor, its not unusual for the advance mechanism to be frozen so you have no advance what so ever....the TH350 will handle lots of power but you run out of top end gearing thats why the overdrive trans are so popular
Le Mans Master
Joined: Apr 2005
Posts: 6,346
Likes: 418
From: Seattle Area WA
The stock cam and intake are good on the L82. I agree with Bob, first rebuild and recurve the distributor for 36 degrees by 2,800-3,000 RPM. If you want to advance the cam 4 degrees for some bottom end you can do that too. A good dual exhaust with or without headers. New heads with 64cc chambers to get some compression to make some power.
Le Mans Master
Joined: Oct 2010
Posts: 6,928
Likes: 841
From: melbourne florida
2023 C3 of the Year Finalist - Modified
the l-82 short block is identical to a 72 lt-1 except the cam. distributor, Carb, and exhaust go a long way on that engine cam and heads its equal to a zz4. why don't people understand an l-82 is any excellent foundation to build on forged crank forged rods forged pistons, your beloved zz4 has powdered rods and hyperutectic pistons.
Instructor
Joined: Nov 2010
Posts: 160
Likes: 1
If you're like me and have a limited budget after a Vette purchase:
Free: advance the timing at the distributor, set the idle as low as possible without dying
$100s: full length headers, 2 1/2 exhaust and high flow cats if needed, rebuild carb, new coil, dist cap and wires
$1000s: aftermarket heads
In that order!
Or do what my buddy did and put it all on a credit card:
Free: advance the timing at the distributor, set the idle as low as possible without dying
$100s: full length headers, 2 1/2 exhaust and high flow cats if needed, rebuild carb, new coil, dist cap and wires
$1000s: aftermarket heads
In that order!
Or do what my buddy did and put it all on a credit card:
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Ok, here's my 2 cents worth:
1: recurve distributor (cheap!)
2: Tune carb (less cheap)
3: headers and dual exhaust (will cost some, but worth it)
4: Maybe.....pull the heads and replace head gasket with .015 shim gasket, which will bump compression about 1/2 a point. (I'm not sure if this last point would really be worth the hassle, but it wouldn't cost much, and that big L82 cam screams for compression)
Do the first 3, and that car will rip!!!
Scott
1: recurve distributor (cheap!)
2: Tune carb (less cheap)
3: headers and dual exhaust (will cost some, but worth it)
4: Maybe.....pull the heads and replace head gasket with .015 shim gasket, which will bump compression about 1/2 a point. (I'm not sure if this last point would really be worth the hassle, but it wouldn't cost much, and that big L82 cam screams for compression)
Do the first 3, and that car will rip!!!
Scott
Last edited by scottyp99; Feb 2, 2011 at 01:53 PM.
Instructor
Joined: Nov 2010
Posts: 160
Likes: 1
Melting Slicks
Joined: Jun 2009
Posts: 2,709
Likes: 3
From: Savannah GA
Mark... edelbrock.com search Power Package and Power Package Top End Kit. There are several different combos, and levels of complexity. You can pretty much order a killer top end in a single box, delivered to your door.
Race Director
Joined: Apr 2007
Posts: 14,062
Likes: 602
From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
Melting Slicks
Joined: May 2006
Posts: 2,590
Likes: 403
From: Nashville TN
St. Jude Donor '09
You have several devices connected to you intake and carb that control accessories like brakes, distributor, head lights, and transmission. A leak in any of these rubber vacuum lines can cause engine to run irregular. So make sure all the vacuum sources on your carb are either connected or plugged/capped. Also check you rubber lines to make sure there are no cracks.
I rebuilt my distributor and set timing as described above and was very surprised how much better the car performed. As stated, check the simple things first. These were mid-70s cars and they were all dogs in my book. Your L-82 bottom end has good parts in it and strong enough to handle some pretty decent HP, assuming your compression and leak down test look good. You have to weigh whether you want to save that motor until having matching numbers becomes more important in the future of the rubber bumper cars or just upgrade what you have.
Keep asking a lot of questions and read as much as you have time to here on CF. There is a ton of information here that will help you make the decisions that are right for you. Come up with a plan and we'll be glad to critique it for you.
I rebuilt my distributor and set timing as described above and was very surprised how much better the car performed. As stated, check the simple things first. These were mid-70s cars and they were all dogs in my book. Your L-82 bottom end has good parts in it and strong enough to handle some pretty decent HP, assuming your compression and leak down test look good. You have to weigh whether you want to save that motor until having matching numbers becomes more important in the future of the rubber bumper cars or just upgrade what you have.
Keep asking a lot of questions and read as much as you have time to here on CF. There is a ton of information here that will help you make the decisions that are right for you. Come up with a plan and we'll be glad to critique it for you.
Intermediate
Joined: Dec 2010
Posts: 44
Likes: 0
From: Fenwick West Virginia
It seems there is no general consensus on how to generate more
horse power.
The first thing I would do is pick up a copy of
"How to Build Max Performance Chevy Small Blocks on a Budget".
It provides 10 engine builds that produce good HP.
The L-82 has all the compression you need for 300-350 HP.
The heads are OK also. If you really want to change them
go for a set of Cast Iron Vortecs. They flow very nicely and are
the most cost effective choice. Others will say you must go aluminum.
All things being equal the iron head will out perform the aluminum.
I like the Edelbrock Performer RPM Manifold with a 750 Holley.
If you chose Vortec heads make sure you get the correct intake.
Your L-82 intake will not bolt up.
I like the LT-4 hot cam. In order for you to use it your block will
need to be machined. For 300 - 350 HP a 1970 LT-1 cam would be fine.
Last but not least get a set of equal length tube headers.
Make sure you select headers with 1 5/8 primary tubes. Anything larger will adversely effect your low end torque.
BoL...
horse power.
The first thing I would do is pick up a copy of
"How to Build Max Performance Chevy Small Blocks on a Budget".
It provides 10 engine builds that produce good HP.
The L-82 has all the compression you need for 300-350 HP.
The heads are OK also. If you really want to change them
go for a set of Cast Iron Vortecs. They flow very nicely and are
the most cost effective choice. Others will say you must go aluminum.
All things being equal the iron head will out perform the aluminum.
I like the Edelbrock Performer RPM Manifold with a 750 Holley.
If you chose Vortec heads make sure you get the correct intake.
Your L-82 intake will not bolt up.
I like the LT-4 hot cam. In order for you to use it your block will
need to be machined. For 300 - 350 HP a 1970 LT-1 cam would be fine.
Last but not least get a set of equal length tube headers.
Make sure you select headers with 1 5/8 primary tubes. Anything larger will adversely effect your low end torque.
BoL...
