Hello to all you very knowledgeable and helpful people. I am a newbie here.
I hope I am posting this in the correct section???

I have spent countless hours researching and reading your very helpful topics since importing my 75 L82 convertible from Canada.
I do not intend to fully rebuild the engine at this stage; I will pull it down check tolerances and go from there.
The car has 65,000 original miles on it; it is a four-speed manual M21, 3.55 diff and Gymkhana suspension. The cats have been removed and what looks like a pretty standard 2” exhaust system fitted.
It otherwise seems stock. It’s not blowing smoke and is not rattly; it does have a few minor oil leaks.
I have completely overhauled the brakes and freshened up the suspension with new shocks, rubbers, bushes etc. etc. etc. The car has been sitting for quite sometime so needs some TLC. Later I will install a composite rear spring.
I am now putting together a shopping list in readiness to pull the motor and gearbox in the winter to give it a new clutch, fix the oil leaks and to try and get a few more horses from it. I want to keep the stock Carb and Air Cleaner if possible.
Below is what I am proposing; any comments or suggestions to this will be appreciated. Also some questions on whether I am on the right track. I don’t want to spend a fortune as I think the car needs a full resto…… but hell I’m too old!!!!
How do I determine the Push Rod length?
What are the best head bolts?
Should I change the exhaust system to 2.5”

Airflow Research (AFR) 1006 - AFR 195cc SBC Enforcer Cylinder Heads
Cylinder Heads, Enforcer, Aluminum, Assembled, 64cc Chamber, 195cc Intake, Angle Plug, Chevrolet
COMP Cams SK12-268-4 - COMP Cams Xtreme Energy Cam and Lifter Kits
Cam/Lifters/Timing, Hydraulic Flat Tappet, Advertised Duration 268/280, Lift .477/.480, Chevy, Small Block
Edelbrock 2701 - Edelbrock Performer EPS Intake Manifolds
Intake Manifold, Performer EPS, Dual Plane, Aluminum, Natural, Square Bore, Chevy, Small Block, Each
Fel-Pro 1204 - Fel-Pro Performance Intake Manifold Gasket SetsGaskets, Manifold, Intake, Steel Core Laminate, 1.99 in. x 1.23 in. Port, .060 in. Thick, Chevy, Small Block, Set
Summit Racing SUM-G5212 - Summit Racing™ HEI Advance Curve Kits
Distributor Advance, Mechanical, GM, HEI, Kit
Summit Racing SUM-G9003 - Summit Racing™ HeadersHeaders, Long Tube, Steel, Painted, Chevy, Small Block, PairARP 134-3701 - ARP High Performance Series Cylinder Head Bolt Kits
Thanks to all in anticipation

 

I can’t answer your questions. I will recommend you purchase the year specific GM service manual, or the Haynes and the assembly instruction manual (AIM). Best of luck Bill

 

nice.

 

With 3.55's and a 4 speed you can probably go bigger on the cam. Something around the comp XE274H size would be be my choice since you will be about 10:1 compression.
Push rods will "probably" need to be around +.10 , but get the length checker to be sure. You should plan on roller rockers also.
Hooker makers headers and a dual 2.5" exhaust kit that's decent and mostly bolt in for c3's.

Those thing will increase the fun factor.

 

I recommend the Trick Flow "DH 175" head over the AFR as it has a smaller port and a 60cc chamber that will get you just over 10 to 1 compression. I have a set in my workshop and they are top notch......the smaller port on a 350 will make it more responsive around town and overall......
The 134-3601 ARP bolt set is a 6 point set and $20 cheaper......12 pt. is unnecessary here.
The EPS intake is a good one......but go with the 2101 Performer and keep your Q-Jet.....the EPS is square bore only.
The Cam is a great choice and has been one of Comp's best selling cams for over 30 years......it flat out works. I have a Howard's Hyd. Roller that is much better though.
You will need to measure for pushrods........use a 1003 Fel-Pro head gasket.
The curve kit and headers are fine too....use a 1404 Fel Pro header gasket and Percy's collector gasket......plumb into a 2.5" true dual system with a good muffler.
If you have the budget...I recommend the GM "806" crate motor distributor https://paceperformance.com/i-625171...stributor.html this unit comes pre curved...drop it in and time it.
You will need a 9-1100 Cloyes timing set and I urge you to install a new balancer......https://www.summitracing.com/parts/sum-161350 This Summit piece is well made, has timing marks on it and installs easy without too much press fit. https://www.summitracing.com/parts/mor-60110 Use this timing pointer......I have measured over 15 of these and each one was spot on out of the package....it should be checked but they are spot on.
This is easily a 400+ hp combo.....should run very strong with a 3.55 and the M21.......I wouldn't do anymore cam with the M21 though......the 2.20 low 1st gear is soggy out of the hole with big cams.....

Jebby

 

I agree with some of the above, I think he is a little generous on the compression ratio. Maybe closer to 9.5 to 1 with stock pistons.

Painted headers will come back to haunt you within a couple yrs. They scratch easily and will peel / flake. You will be way ahead of the game going with Ceramic right from the get-go. Twice the cost, but a good investment with good returns.

The Eddy 2101 Intake is very popular not so much for horsepower but because it fits under the hood easily and saves some weight.
Myself, I ditched the Quadra for a Holley which will fit the 2101 also.

You can purchase pushrods for $19.99. DON'T. Figure on $80- $100 a set. Harden, one piece and proper length will prevent issues later on. One piece means just that. Top quality, without the ball pressed in the ends.

Not a big fan of roller rockers on grocery-getters. They need tall valve covers, special rocker lock nuts that some people can't seem to get the valve-lash right.
However, Roller-Tip rocker is an excellent alternative.

 

The compression is about 10 to 1 as it is a 60cc chamber on the Trick Flow......they really should make a 64cc...but they don't. Even .020 in the hole with 4 eyebrows (L-82) and a .039 1003 Head gasket gets 10.4 to 1......which is fine with the fast burn chamber but you are going to have to run 91 in it.......
I agree on Ceramic Coated headers.......they reduce the temp of each tube by over 200 degrees......this is heat that radiates everywhere and makes your Vette hot.......hot running, hot inside the car...etc.....
The pushrod advice is the ONLY advice there is too.....it is critical to get the correct pushrod length.....this is an area that many just fluff and is not an area to mess around with. Too long or too short of a pushrod will constantly sideload the valve in the guide creating premature wear.....there is a simple tool for this.....let us know when you get to that point. I just purchased a set from Trick Flow for $110. Your engine makes a million valve cycles in its life.....don't let the valve sideload......
The Comp fat aluminum roller rocker actually do fit under the stock valve covers......the Trick Flow head valve cover rail is 1/2" higher than stock....BUT, the drippers inside the cover must be broke off.....I just mocked this up last weekend so I am sure of it.....use the 1628 Fel Pro gasket....expensive, but .250 thick and they are the last ones you will ever buy.
The 2101 Performer is a surprising piece......but the EPS is better if you can use it.....I would pair the EPS with a 0-90770 Holley 770 Truck Avenger for a snappy setup......I am using the EPS, TFS heads, The Truck Avenger and a Howard's hyd. roller cam in a 358ci build right now......it will make 400hp through 2.5" Rams Horn manifolds.....425 through headers......

Jebby

 

Freidburger (sp?) has a dyno shoot out video and a ported 2101 hangs with a un ported RPM to 500 horse power

 

First off, this is only my opinion as to what I did with my '76 L82 several years ago. It needed a complete rebuild because it was weak and tired. Rebuilt the engine w/ OEM .030 forged pistons and reground stock forged crankshaft. I retained the stock (rebuilt) heads w/.194 intake valve and a custom-ground hyd. camshaft from Cam Technics (no longer in business) in Sarasota FL. The cam was special for the L82 w/ Turbo 400 trans. I eliminated all the smog parts and used an Edelbrock Performer spreadbore intake w/stock carb. The exhaust is for a 1970 LT1 350 (2-1/2") and no Cat. The dist. was new OEM stock set for 36 degrees total advance.
This car woke up like I never would have expected. I would pin myself to the back of the seat under full acceleration (3:55 Posi rear). Not a race car, but tons more torque & HP than it ever was. I don't know the cam specs, but the combination was excellent. Good luck with your C3, but you may want to keep your heads.

 

Thanks to all those that have replied, your advice is greatly appreciated, budget is always a consideration, however I will definitely go with the ceramic Headers etc as detailed. I have been given a new 2701 performer by a mate, will this still fit with the Quadrajet and standard air cleaner?
I probably should have mentioned, we still have the option of 95 octane here which I intended to use in the engine, is this better or should I use 91 and or a good octane booster?
I also note that the Trick Flow 175's listed are 56cc Chambers???? I am concerned that will raise the compression too much for an older engine?
Thanks in anticipation

 

As I said:
The 2701 does not work with Q-Jet…2101 for Q-Jet.
The TF 175’s are 60cc chambers, you are looking at the ones for 305’s
You will not need any more octane higher than 91….octane is not power, it is resistance to combustion.

Jebby

 

I had my painted hooker headers sandblasted and then coated them with Eastmans ceramic coating inside and out. It worked well as long as you follow the break in procedure and a lot less than factory ceramic coated.

Brodix Ik180's with 64cc chambers are worth a look also, very reasonable price and good flow rates. That would keep you around 10:1 compression. I think they are running around $1100 US for the US cast and made set.

 

Personal opinion.... I think you will be throwing money away if you don't keep the stock intake manifold and Q-Jet.

{Let the sparks fly!!}

 

You're kidding.lol where has jbl82 gone? You must be his replacement. Anybody hear from him?

 

what ever head you get make sure the spark plugs clear the headers that are chosen , my headers required straight plugs not the angled . On my 1980 L82 I went with with Promax 183 aluminum 64cc heads with a Edelbrock 2101 intake , factory Qjet , headers and a Comp Exreme 262 which has slightly less duration but slightly more lift than the L82 cam ,. engine can pull 1450 rpm full lock up in 4th gear (700R4) and crank out a 13.60 at 102.8 at Kil Kare Dragway all while getting 17.5 mpg city , it's a nice daily driver package

 

The Brodix IK's are a good choice......one thing I like about Brodix is they helicoil all threaded holes....
The Dart 180 Pro 1 is a good choice too......these heads outperform anything else I have used on a street 355 but they are getting pricey.....Dart heads are wet flow tech.....and the actual flow numbers are not indicative to their performance.

10.5 to 1 is not an issue anymore with fast burn chambers and 91 octane fuel......LS stuff has been around that from the factory for quite some time....

Jebby

 

Trescar,

Eric, post 15, brings up a valid point. I noted in your opening post that you wanted "Angled Plug" heads. Why is that? For the extra 5 H.P?

Angled plugs, from what I have seen, cause more hardship than they are worth. Those plugs may not clear headers and more than likely will burn your plug wires.
This is something to think about when trying to remove / install the plugs.

 

[QUOTE=Jebbysan;1604388783]I recommend the Trick Flow "DH 175" head over the AFR as it has a smaller port and a 60cc chamber that will get you just over 10 to 1 compression. I have a set in my workshop and they are top notch......the smaller port on a 350 will make it more responsive around town and overall......
The 134-3601 ARP bolt set is a 6 point set and $20 cheaper......12 pt. is unnecessary here.
The EPS intake is a good one......but go with the 2101 Performer and keep your Q-Jet.....the EPS is square bore only.
The Cam is a great choice and has been one of Comp's best selling cams for over 30 years......it flat out works. I have a Howard's Hyd. Roller that is much better though.
Hi
On you advice I have decided to go with a Hyd Roller now after reading up!!! what would you reccomend?

 

Thanks Eric
I have ordered a set of Flowtech Ceramic Coated Headers..... I have not decided on the heads until I work out whether straight or angled heads work best with the flowtech headers...... There is a pair of Sportsman II Cast heads for sale here in Au....They are angled plugs!!!

 

hyd roller lifters can be had for 125 bucks on ebay. dont even think about it. howards are expensive. they also wont come apart.