I have the original 350 L-82 that came in my 73. I have an opportunity to get some new Edelbrock Heads (part # EDL-2098) for a small Chevy, 410hp, w/hydraulic flat tappet cam and lifters, as well as an air gap manifold, would then install 750cfm carburetor(part # 1407) all at a great discount, over20%. The horse power is very low for these years as you all most know; do you think I’m messing with the “originality” of the car or any other issues I’m not aware of?

 

If it is street driven I'd say you'd probably be happy with that horsepower. If your getting such a good deal I'd say go for it. As long as your not trying to keep it all original for resale and/or bragging rights

 

If you're looking at the eb RPM cam ... you probably would not like it in a street car ... most folks don't. The heads'll be fine ... your OE carb will be too if it's tuned/built right ... 73 L82 OE Qjet flows 750cfm or more. Air gap intake might fit under your hood maybe not ... dunno ... more than one version. IMHO ... a load of stuff at 20% off is fine ... but if it's not optimal for you then even 50% off is a bad deal.

 

What is it about the cam do folks not like?

Not a big mechanic on engines, hence the posts!

Thanks for your input!

 

not sure of the cam you're referring to, but why can't you select a different cam? is the deal on that cam only?
as for originality, that's not a big deal as long as the originals don't go anywhere. they don't take up a whole lot of room so just stick 'em in the corner for later.
BTW, the '73 L-82 wasn't really that weak anyway. what, 225hp? figure if that was SAE gross figures, that would be about 300-ish horsepower.
the biggest disadvantage i see with the aluminum heads will be the possibility of too large a chamber size to make it worth the while. you'd probably need a 64cc chamber or smaller to see any gain. you're going to want a bump in compression to take advantage the aluminum heads. your iron heads are either 72 or 76cc as it is.

 

The 2098 top end kit includes.
Performer RPM hydraulic cam/
lifters #7102.
two performer RPM heads
# 60899.
timing cover and seal # 6997
cylinder head gasket set # 7361
RPM air gap intake manifold # 7501
intake manifold bolt kit # 8504
cylinder head bolt kit # 8550.

The #7102 performer RPM hydraulic flat tappit cam
is a little radical for a 350 even if it were a 4 speed,
if its an auto car you would have a real mess on your hands without a high stall converter. Here are the specs on the cam.
Int. Dur. .050 = 234
ex. dur. .050= 244
adv. int. dur.= 308
adv. ex. dur.= 318
lift int.= .488
lift ex.= .510
LSA 112

The #7501 RPM intake is strictly square flange you would not be able to
keep your Q-jet with it. It would fit under your 73 hood but to use it
would mean you have to use a drop base air cleaner to make it work,
so your stock cowl system would not work.

The 60899 heads are 64cc will work good big improvement for compression
over the 76cc factory heads, but you may want to check into # 7361
gasket set my guess is they may be .041 thick, steel shim
gaskets were .018 thick. if your block is original never been decked the
.041 gaskets will kill off some of the gain of the 64cc chamber heads.

Brodix has a good price on its IK180 heads around $1050.00 you may be
better off picking out your own parts for a top end kit.

 

Little Mouse covered it well.

Too much cam makes for a sluggish, slow motor in typical street rpm range ... so slow, a tired stock L48 can often outperform.

Even when mfg indicates aok, I don't think much of steel shim gasket w/ soft casting on street ... my .02

 

750 carb way bigger than needed. 650 would be adiquate.
Airgap intake won't fit under stock hood.
64cc combustion chamber may be too small if you "upgrade pistons and/or rods. Stock 350 piston/crank stroke is 3.48 inches.
You'll need to match the intake runners with the head runners to minimize flow turbulence. That may take some grinding. Angle plugs won't buy you anything for street use (if the heads have such).
Do a search for compression ratio calculators on the web; you'll find some useful info for planning.
Flat tappet cam OK for street. Roller if you can afford it, but not really needed for street. Roller rocker the tops in any case.
Have the new heads sent to a local shop for a valve job; they're going to need it. You've got to match the valve spring rate with the cam too.
If you have the room, replace all the head bolts with studs.
Now, depending on how many miles you have on your engine, keep in mind that all new heads with smaller combustion chambers will increase the cylinder pressures and may lead to premature failure of the old piston rings.

 

Little Mouse, Thanks for all the information. It seems to me after looking into doing this that for the money output and things not lining up correctly I will just rebuild the stock engine. It appears as if no matter what I would do without the correct airflow I will not be gaining much and not wanting to retro-fit anything on a stock original. Thank You guy's for all the input as it has been a huge help in making a decision.

 

Don't get discouraged that easy a set of modern heads would really
help the breathing on your engine, raise your compression up.
With a modern cam you can run a little less duration then the original
L/82 cam, less duration will bring your power in at a lower rpm and a
modern cam has a little more lift. You can use the performer
edelbrock intake its basicly an alumuninum replacment for you stock
intake will allow you to keep your Q-jet. Brodix has been making heads
since the 1970s has a good reputation for quality and power, they make
heads for street engines to all out race engines, they even make
aluminum blocks.

I ordered a new 1978 L/82 it had a M/21 with 3.70 rear, a 78 is a
little heavier then your 73 and the exhaust system on it was not as good.
but my opinion of it the L82 cam it did not make good power down low and
was nothing special up higher in RPM. If I owned your car wanted to keep
the stock air cleaner, here's the parts I would buy for it.

Heads # BRO-1021004 = $1013.95
cam/lifters # LUN-60102LK = $189.95
intake # EDL-2101 = 119.95

www.summitracing.com
www.brodix.com
brodix ph # 479-394-1075

 

I Have A 1980 L82 I Used Comp Cam Extreme Energy Cam 262, Rhs Heads 72cc Chamber 180cc Runners My Stock Compression Was 9 To 1 It's About 9.25 To 1 With These Heads , Mas Flo Fuel Injection ,car Runs Very Strong, Every Fits Under Stock Hood

 

Garmey- I tried to return your PM it came up that you do not recieve
PMS So I can not get through to you.

 

I'll check and re-do if needed!!

 

It's turned on ?

 

Ok I will send you a PM in a little bit.

 

It would help if you ID'd your trans & rear gear ratio.

Some will poopoo these 2 suggestions ... a hypereutectic piston & a popup aka dome piston. Well, hypers are OE in virtually all motors today & there's some dang highly efficient OE stuff out there now ... as for popup you can still get very good performance with them ... simply ask CF member dmaaero ... IIRC he has H618CP speedpro/sealed power hypers with a small dome in his street C3.

When you "rebuild" ... Run H618CP pistons with OE Iron GM 76cc heads and a steel shim gasket and a nice street cam ... it'll look stone-stock & make lotsa power (~ 9.8:1 scr) but won't cost lotsa $.

Or ... rebuild w/ hypers w/ small dish like sp H670CP with Iron GM Vortec 64cc heads (~ 9.6:1 scr).

 

It's an Auto trans, and can't tell from Build sheet what rear gears. I would presume whatever was stock that year 3.36:1?

 

I took Jacksons advise and went with those speed pro pistons .30 over and 76cc heads and expect to put on the engine test stand next week.
Sounds like a great combo. My machine shop builds race engines and agreed that it is a great combo which will keep all the stock castings and still make good power.