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Old 04-19-2019, 01:01 PM
  #21  
jackson
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Always install new HFT lifters with new HFT cam ... that why I suggest a kit ... cheap $112

Hi-octane? ... maybe ... cam choice matters ... longer duration effectively bleeds off some compression.
Old 04-19-2019, 01:02 PM
  #22  
wgrea3
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Originally Posted by jackson
those heads don't have rocker arms or rocker studs: need all ... can spend under $100 or over $300

need pushrod set ... spend $30 to $130
adds up quick
I'm a noob... can the exsiting rocker arms and pushrods be re-used? Is it impossbile or just a really bad idea?
Old 04-19-2019, 01:19 PM
  #23  
jim2527
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Originally Posted by wgrea3
I'd say I'm willing to put $1k into the upgrades.
Vortec steel heads, Edelbrock vortec intake, cam. Your still gonna be over budget.
Old 04-19-2019, 01:25 PM
  #24  
jackson
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Originally Posted by stingr69
OP has a decent basic crate motor so use it.......add a Comp 268H cam and tune for it. Save money for the next upgrade.

that works too
Old 04-19-2019, 01:27 PM
  #25  
gkull
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Raise the compression and head flow. Trick flow sells some 60cc double hump 175 cc heads made for all low compression small blocks
Old 04-19-2019, 01:49 PM
  #26  
BKbroiler
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Originally Posted by wgrea3
I'm a noob... can the exsiting rocker arms and pushrods be re-used? Is it impossbile or just a really bad idea?
You can reuse your original rocker arms, as long as cam lift isn't too high, and as long as you're using a flat tappet cam you can reuse your original pushrods.
Old 04-19-2019, 02:30 PM
  #27  
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your best bet is to call a cam company tell them what you have so they can recommend a cam. This and maybe a stall converter to stay under budget,
Old 04-19-2019, 09:57 PM
  #28  
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Find some C4 Corvette aluminum heads with the 58cc chambers and a cam with around 218 duration at .050 and you will be happy.
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Old 04-20-2019, 02:51 PM
  #29  
Jebbysan
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As stated.....put a real camshaft in it.....the Goodwrench 350 had the 305 H.O. camshaft in it.....tiny. The 268H Comp is perfect for this.....even at 8 to 1 compression, it works.
Do not waste time on that L-82.....nothing there worth salvaging if it has a broken rod.....the heads are not that great either, 2.02 valve or not.....they are just as good as the heads on the Goodwrench engine.
Read this: http://www.superchevy.com/how-to/463...-engine-build/ Part 1
http://www.superchevy.com/how-to/463...gine-build-ii/ Part 2
Part 2 utilizes the 268H camshaft and pocket ports the heads.....with intake,cam,pocket port and long tube headers....this made 336 horsepower...or on par with a 69 350/350.

I also believe that the ZZ4/L98 head is a waste of time too.....they do not flow any better and have a funky exhaust D-port pattern that some headers do not work with.....even with the 1.5 to 1 compression boost...they are only worth 20-25 horsepower...and that is ALL compression. Typically you will see 15 horsepower per point of compression.
This part explains the L98 head...a waste of money: http://www.corvettefaq.com/c3/goodwrench/gm3503.htm

Jebby
Old 04-21-2019, 10:24 AM
  #30  
wgrea3
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Originally Posted by cuisinartvette
What rear end gear, 3.70? Even a GM Hotcam would work great, they arent much at summit. A 650dp and youre set , ought to have a strong runner that will have good manners and be maintenance free
It was an L82 4 speed with M21 close-ratio trans. So that should make it 3.70, correct?

Last edited by wgrea3; 04-21-2019 at 10:25 AM.
Old 04-21-2019, 11:14 AM
  #31  
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Originally Posted by wgrea3
I'm a noob... can the exsiting rocker arms and pushrods be re-used? Is it impossbile or just a really bad idea?
Likely the base circle of the cam will be different. Also the new lifters could be taller or shorter changing the geometry as well. Also should be running hardened pushrods too. Not saying the stock ones won’t work, but I kinda doubt it.

As for the rockers. You can reuse, but for a small amount of money you can simulate a larger cam with 1.6 rockers and take some friction away. Basically you can get a few more degrees of duration @.050 lift and alittle more lift at the valves. That’s a personal call there.

Last edited by kossuth; 04-21-2019 at 11:19 AM.
Old 04-21-2019, 11:24 AM
  #32  
stingr69
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Originally Posted by wgrea3
I'm a noob... can the exsiting rocker arms and pushrods be re-used? Is it impossbile or just a really bad idea?
You actually have 2 sets to choose from if you include the L-82 engine pieces. The L-82 has hardened push rods and guide plates and screw in rocker studs. If the parts are still good and they are compatible with your head choice and cam style, you can consider them, Depends on your other choices and condition of the pieces.
Old 04-21-2019, 11:33 AM
  #33  
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Originally Posted by wgrea3
It was an L82 4 speed with M21 close-ratio trans. So that should make it 3.70, correct?
Most likely yes! BUT there were VERY few wide ratios made with the L-82 4 speed but extremely rare, something around 400 wide ratio 4 speeds. There was recent thread with the actual number....I have never seen a 78/79 L-82 with a wide ratio 4 speed and factory 3.36 gears but it is possible...see my chart below

From the other thread:

"In 1978, there were only 382 units built of L82+M20+GV4 (that’s the G95) so they are going to be super rare."

in 1978, there were only 33XX 4 speeds in total made with the L-82 90% were the BW close ratio......

Last edited by jb78L-82; 04-21-2019 at 11:58 AM.
Old 04-21-2019, 11:34 AM
  #34  
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Old 04-21-2019, 11:52 AM
  #35  
GTR1999
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I would say think about what you want from the car.

For example. I bought 2 Targetmaster 350's when they came out in 78 and again in 80. These were USA made to my knowledge and they went into my street vettes I used for daily use. The 78 I just pulled the nylon timing gear out, installed a Streetmaster intake and dialed in the Q-Jet. I ran great, had all the power I needed to drive everyday, got 16mpg on trips driving 65 mph with 370 gears, and really was a nice engine right up to the day I stupidly sold the car.

The 80 engine went into my 69 M20 336 vette. Again swapped out the timing set for a double roller, used an SP2P intake w/ Q-jet, Stock exhaust and drove it all over the place. Was it a drag car no not at all but it kept up no problem, I never had a problem with it, got 18 mpg at 65 with the 336's, and put 18k miles on it before my son took it, slapped on WP iron heads, a mini blower, cam, and headers and beat that crap out of it to date. The bottom end is all stock and I am surprised it didn't break yet. He blew up two 4 speeds, twisted the driveshaft, imploded a 355 diff, ran a 411 super 10, bent 1350 12 bolt axles, ripped the snubber bracket from the frame and yet that engine is still together. Still has the blower, now a Tremic, and a 1480 12 bolt I built him, the only thing that finally stopped him was 2 kids and a mortgage!!!!

Now my friend bought later versions that were made in Mx and they did not last, had a lot of valvetrain issues so what can I say. That L82 would be a good foundation to build a nice street eng like Jeff did but even with you doing the work it will cost a lot more then a $1000. The more power you have and drive it hard the more weak areas south of the flywheel you will find. Me, I would use the 268 cam setup and drive it.

Good luck
Old 04-21-2019, 12:08 PM
  #36  
jb78L-82
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Originally Posted by GTR1999
I would say think about what you want from the car.

For example. I bought 2 Targetmaster 350's when they came out in 78 and again in 80. These were USA made to my knowledge and they went into my street vettes I used for daily use. The 78 I just pulled the nylon timing gear out, installed a Streetmaster intake and dialed in the Q-Jet. I ran great, had all the power I needed to drive everyday, got 16mpg on trips driving 65 mph with 370 gears, and really was a nice engine right up to the day I stupidly sold the car.

The 80 engine went into my 69 M20 336 vette. Again swapped out the timing set for a double roller, used an SP2P intake w/ Q-jet, Stock exhaust and drove it all over the place. Was it a drag car no not at all but it kept up no problem, I never had a problem with it, got 18 mpg at 65 with the 336's, and put 18k miles on it before my son took it, slapped on WP iron heads, a mini blower, cam, and headers and beat that crap out of it to date. The bottom end is all stock and I am surprised it didn't break yet. He blew up two 4 speeds, twisted the driveshaft, imploded a 355 diff, ran a 411 super 10, bent 1350 12 bolt axles, ripped the snubber bracket from the frame and yet that engine is still together. Still has the blower, now a Tremic, and a 1480 12 bolt I built him, the only thing that finally stopped him was 2 kids and a mortgage!!!!

Now my friend bought later versions that were made in Mx and they did not last, had a lot of valvetrain issues so what can I say. That L82 would be a good foundation to build a nice street eng like Jeff did but even with you doing the work it will cost a lot more then a $1000. The more power you have and drive it hard the more weak areas south of the flywheel you will find. Me, I would use the 268 cam setup and drive it.

Good luck
Amen Gary!

My L-82 rebuilt with me doing the engine removal/install, buying all the best parts (AFR heads, Howards Roller cam, JE Forged racing pistons), reusing the L-82 reconditioned forged crank, L-82 reconditioned rods, L-82 ported aluminum intake, comp cams double roller timing chain from the L-82 by me, comp cams 1.52 roller tipped rockers, melling oil pump, AC delco fuel, pump, Felpro gaskets , RAM HDX clutch kit, reconditioned OEM flywheel, motor mounts, etc about $5,500 all in with builders machine work and expertise in areas, maybe a bit less. The funny thing is that the L-82 is a great foundation to build an easy 425-450 Gross HP street engine with today's parts. Can't imagine the number of L-82's junked over the years unnecessarily because the engines potential was not realised to utilize the basic forged foundation of these motors..............Shame

Last edited by jb78L-82; 04-21-2019 at 12:11 PM.
Old 04-21-2019, 12:46 PM
  #37  
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I dont think a lot of people realized they had a decent crank, 4 bolt mains etc
Back then it was just a smog motor to most & offerings of roller cams, good heads just werent what they are today. Getting 400hp out of a 350 was a chore and 12/13 sec cars were a big deal

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Old 04-21-2019, 10:53 PM
  #38  
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Hey everyone. Thanks for all the info. I've learned a lot this weekend with your help. It sounds like putting in a new cam is gonna be the most bang for the buck I can get, and if I'm limited in budget to $1k right now, maybe I should just focus on the cam and put some extra money into a roller cam?
Old 04-22-2019, 08:10 AM
  #39  
jackson
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Originally Posted by wgrea3
Hey everyone. Thanks for all the info. I've learned a lot this weekend with your help. It sounds like putting in a new cam is gonna be the most bang for the buck I can get, and if I'm limited in budget to $1k right now, maybe I should just focus on the cam and put some extra money into a roller cam?
You won't find so many folks who've put a pricey roller setup in a NA street motor with both *76 cc heads & *dish pistons (* + * = low comp)

AKAIK, so far, GM has not.

When you put a large cam in a motor having relatively low compression, you are repeating the most common error in cam choices.

In addition to their lifters, Roller camshaft itself is much more pricey than a flat tappet shaft.
Don't think anyone would want to buy a small roller shaft ... then buy a larger one after upping compression.

? How about save that $1K for now; and begin saving for better heads? Choose & Install heads and cam in concert.
Old 04-22-2019, 08:37 AM
  #40  
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This may not be the answer you are looking for, but I wouldn't touch that engine with a $1K budget. You will blow through that and more, and then make compromises you regret later.

You already have a 4-speed, so go drive your car! The low hanging fruit is a Lars-style ignition tune, which could be free, or a few $hundred if you need to replace everything. Then put the rest into suspension mods. Not sexy, but your car will feel a lot faster, and you will be better prepared for more power.

Nothing feels worse then spending money twice, or doing work twice, to solve a problem. Figure out where you want your car to be in a few years, and only fix the what you can afford to do correctly the first time. Good luck!
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