I've got a 1974 Stingray L82/4 speed and I'm looking for advice on bolt-on upgrades that won't break the bank. I'm not looking for big power, just something around 325-375hp to wake the car up a little bit. I had in mind heads, intake manifold, carb, cam, and headers but am not sure of many of the specifics. I'm a 19 year-old college student and eager to learn whatever I can about my car. Any advice or suggestions are greatly appreciated.

 

The SBC has been modified for over 60 years now and there are a million recipes to do what you want. (google and search this forum). There are no secrets left. The recipe for you depends on what your goals are.

If you don't want to raise rpm, loose torque, loose gas mileage or impact reliability then my recommendation is just a set of heads with 58-64cc chambers. The L82 camshaft is essentially the same as the L46 camshaft and that engine was good for 350 hp. The only major difference between a L46 and L82 was compression. The added CR would also help torque a lot which is probably what you are after in a street car anyway.

Vortecs are probably first choice but good used aftermarket or '113' c4 heads that are slightly more expensive would also work.

If you kept your low compression heads you would have to change the cam, change intake to raise rpm, etc, etc, etc to get your goal.

.02,
R

 

I'm jealous. I didn't have a ride like that when I was 19!

Edelbrock markets what they call a "Total Power Package" which provides intake, heads, and cam. Add a set of headers and you will have a nice little motor. You will have to do some research to figure out which kit will work for you. Hood clearance will be an issue with most aftermarket intake manifolds. You can, of course, piece together the same sort of package with parts from various sources.

If there is one key to getting power out of a small block Chevy, its setting up the ignition advance curve. It was a bit of a 'secret' when I was your age, but its pretty much common knowledge now. (We won't go into how long ago that was.) Lots of information on this forum about how to do that.

Good luck. Have fun. I did a lot of wrenching when I was your age, learned a lot. But I could only dream of doing it on a Corvette.

 

some jurisdictions/states prohibit changes; some no problem. First verify what you can or cannot do.

x113 aka L98 aka ZZ4 heads ceased production and have become scarce; If you can get em cheap enough they're good for compression bump but little else.
x962 aka L46 aka L82 cam has rather wide intake duration which makes bottom end lazier than many prefer. Suggest more compression & different cam profile.

 

A set of afr 180s, Isky 270 mega cam, headers, used intake if you like will wake that one up big time. Your Qjet is capable....or a 650 double pump would work fine

https://www.summitracing.com/parts/isk-cl201271
7 left in stock..hope they arent discontinuing these?!

Dont skip this!

Vortecs arent bad but youll need to buy a corresponding intake. Honestly I think they are overrated for the gains you get.

 

Do you know the rear end ratio?

 

3.70:1

 

Thank you! I was lucky to get it and get it on the road, with the way the DMV has been lately. A lot of people did me favors that day. Do you have any advice for the timing advance?

 

If youre not sure how to curve it, couple guys here have Sun machines and can do that for you same with your carb.
Gotta decide on what parts you want first.

 

In your situation.....start off with a few mods. Long tube headers and a nice exhaust is probably the first thing I would recommend. From there the 2101 Intake and a GM Performance ZZ crate distributor. Our member here Lars has a great tech paper on how to do your timing.
Quite a few will say the intake is waste but I do not believe that......it shaves pounds and will support up to 380 horsepower with future mods......so will the headers.....it also deletes the EGR and looks great.....you can install 1204 Fel pro intake gaskets to block the heat riser port to keep the carb cool.
Do these mods and see how you like them........the next things after that will be heads and cam.....which are the REAL boost....but big $$$$. If you do not have the $$$$ for heads, pop for a 268H Comp cam, Cloyes 9-1100 timing set and magnum roller tip rockers. Some will say the roller tip rockers are not worth it, but the stamped steel junk the car came with are all over the place for ratio and flex like a college gymnast....
A nice mild cam will wake it up considerably with the other mods........with pocket ported stock heads and all of these mods, you will see 265 horsepower to the tire easy......for comparision, that is what a stock 1998 LS powered Camaro puts down.....
I edited this as I see you have an L-82.....which has a decent cam to start with......do the mods, skip the cam.....see how you like it.

Jebby

 

I would look at the best aluminum 64cc heads in the 185 to 195 runner length you can get. Maybe shop used if you can. A good used edelbrock RPM dual Plane is your next best bet and then a good set of headers. Ceramic coated if you can find a good used set. All of that will improve any engine from just improving the engines ability to breathe. If you have money left then do the cam adn timng chain. A new cam is going to be another good upgrade and look for a cam with high .400s for lift. I had good results right around the .500 lift with Comp Cams high energy cams. Hydraulic cams are easier to deal with but solid lifter cams have better power. Once you learn on the hydraulic cam you can move up to the solid lifters. You will also need to find a good oil you can afford that is high in ZDDP for the flat tappet cams. Its the zinc and phosphorous that was eliminated from most oils by the EPA and if you dont have it the cam will eat it self up on the lifters. If you can afford it I would look at a roller cam so you dont have to deal with it but ht eroller lifters are very expensive..again, tyhe best you can afford on theroller lifters and roller rockers....dont go cheap

A good easy place to learn stuff is on Motortrend on demand. They have some fun shows like roadkill, road kill garage, hotrod garage and engine masters. On you tube you can watch Finnegans garage. Hes from Hotrod magazine as well.

 

A lot of good info here, but the first question would be, do you have to pass a smog check, and if so, is it a visual check or an actual "sniff test". Until you determine that, I wouldn't start buying any parts. And as I'm sure you're aware, the first upgrade you'd need to investigate, is the exhaust system. Unless you can get more air OUT of the engine, there's no use in trying to get more IN.....

 

Please advise if you have a few photos of the top of the engine without the air cleaner. I am asking as an area you can resolve any vacuum issues is the emissions hoses attached to the EGR, at thermostat housing and the air cleaner. Many of those plastic fittings and hoses are sources for erratic idle and performance.

As others have stated, start with some of the quick changes that don't require engine top-end removal:

1. Ignition Recurve. While at it, have the distributor refreshed (do you have HEI or is it points-style ignition?) along with fresh wires and plugs.
2. Tune carburetor for performance (if it hasn't already been tuned). Lars had a q-jet rebuild service for quite a while but may have stopped due to picky customers
3. Full-length 1 5/8" Headers, true dual exhaust with X- or H-pipe to equalize exhaust pulse and good turbo mufflers. I have dynomax super turbo's

You have a good cam as a baseline for performance.

If not enough from above mod's, then 64cc heads as others have recommended. While they are off, add a new intake - Edelbrock 3701 (EGR) or 2101 (non-).

If still not enough and you are now in for over $2,000, then the next step would be a retro-roller cam kit. However, since you will have already paid for a fresh valvetrain with the replacement heads, it would be beneficial to combine with the heads purchase to save on some $$$.

 

Wouldn’t the l82 already have the vacuum advance all in early? As a 79?

 

The improvement comes from modifying the mechanical advance. The vacuum advance is just there for driveability and mileage. And no, as far as I know, the L82 had pretty much the same advance curve as every other motor. Setting it up for a performance curve is by far the best bang for the buck modification.