V8 Stingray

Having to take the heads off the 'vette in order to put a new set of valve seals in, so kind thinking that maybe I should now look at replacing the stock heads for something with a bit more power.

I was looking to go the Vortec road, but I believe these will not fit with the Edelbrock 2101 intake manifold.

Anyone got any suggestions on what else I could opt for? I have a 76 350 L-48 auto.

• The carb is still a stock Rochester - but I'm going to get this rebuilt before I opt for a new one.
• Edelbrock 2101 Performer Aluminium Intake Manifold
• Dynamax BlackJack Aluminium Coated Headers (85008)
• Taylor Pro-Glo ignition wires (78351)
• custom stainless free flowing exhaust (no boxes, and no cat)

Thanks in advance

RunningMan373

I jst went with the new Aluminum Edelbrock E-streets, 64cc chambers, gonna boost your H/P about 100. love them.

http://www.edelbrock.com/automotive_...e-street.shtml


http://forums.corvetteforum.com/c3-t...46833-why.html

V8 Stingray

100 horses from a set of heads alone? surely not!

I thought you would only get 30/40 from changing the heads...

Other than the heads, do I need to buy anything else? i.e. rockers, valves... I've just got a friend to order new head gaskets as well - from looking at your post there is obviously a bit of matching here to do in order to get it right.

jbowles49

Check out the AFR 180 heads. They seem to return excellent results in comparison tests. They come fully assembled.
Good luck

V8 Stingray

Is there a site or something that shows comparison tests / reviews of these heads?

HDSofttailDuce

super chevy or chevy high performance did an article a few months back doing a test on all the aftermarcket heads maybe you can look it up on the net I think the AFR`s were the best for my engine but do your homework & plan ahead for any future engine modifications

RunningMan373

Your stock H/P was 165, i believe, if you match your components right, you'll pick up 150 HP, over stock, probably 120 over what you got now. The low compression along with dog iron heads, 76cc chambers and terrible flow with small valves. go for it! (i did, am very happy)

billla

Without a budget this is a "how high is up" question

There's no way a stock L-48 is going to pick up 150HP from a head swap. Certainly it's a good foundation that with the right cam you can see a nice HP boost. Certainly 1HP/CID at the flywheel with the right choices.

Note that 165HP is SAE NET not at the flywheel.

63mako

Flow data here:
http://users.erols.com/srweiss/tablehdc.htm#Chevy
A cam change and a set of AFR 180 eliminators is the hot ticket.
Dynoed combinations here:
http://www.ryanscarpage.50megs.com/combos1.html

Jim_Harrison

Doesn't he have the low compression pistons? Think it is time to rebuild the whole engine or buy a new crate motor.

PeteZO6

Check the August 2009 edition of Hot Rod mag., pg. 102. They compared the E-Street heads with GM Vortecs. They only complained about the E-Street heads "scrawny" valve springs that they said should be replaced if you're going with a more than a moderate cam.


Pete

RunningMan373

Note they made more power then the Vortecs with their springs.

V8 Stingray

Now, is this not a pertinent question.... if I spend a wad of money on some new heads and a new cam, if I have low compression pistons am I really going to get a good return?

A crate was considered, but that's a whole lotta cash up front... I'm in Ireland, so customs and shipping is gonna kill me. At least this way I can do it in stages.

My car is a '76 L-48 - but the bhp was 180, not 165...... can't I only go with 64cc chambers on the stock block? to go with the 70cc heads wont I have to change the pistons etc.

Budget of about €1k - which equals $1,400... this going to get me far? Obviously I dont want this investment to take me down a one-way-street, but rather pave the way for future upgrades (but something that builds upon what I have already)

jackson

L48 (dished pistons)
$1400USD should get you the heads & gaskets below AND a new hydraulic flat tappet cam&lifter kit (e.g. summit p/n sum-K1103).

perhaps consider GM alum heads aka L98 aka ZZ4 heads. 58cc chambers. GM p/n 12556463 fits e2101 OK. GM head gaskets either p/n 10105117 or 14096405 are good choice w/ alum heads. Both about 0.028" thick & about 5.8cc.

OE L48 w/ L98-ZZ4 heads & either gasket makes about 9.6:1 scr.

That's the very same head that's on ZZ4; don't let anyone convince you its runners or valves are too small for a warmed over street L48.... but ZZ4 heads are not for those planning to break speed records.

Fishndude

I pretty much started with a stock rotating assembly with flat top pistons in my 350.. We bored it .030 over and then installed the Edlebrock performer RPM heads, Edlebrock #1201 intake, HEI ignition, 750cfm Summit carb and a fairly stout cam (Dur .240+ @ .050) and the motor put out 451hp and over 440 ft/lbs torque on the Dyno..

V8 Stingray

Not to open a can of worms here, but from what I understand while flat top pistons will give a slight increase in compression you do this at risk of detonation and need a higher octane fuel? I'm assuming the stock dished pistons are going to be fine for this upgrade?


I see different chamber options, 58cc, 64cc, 70cc - which of these will fit on the stock SB without other modifications?

Any what kinda torque/hp results would be achieveable with this?

V8 Stingray

Assuming there is a safe point here as to how far you would want to go before putting additional pressure on the lower end of the engine, gearbox, driveshaft etc?

400 horses/torque would be perfect if I could get that far, but not too sure Id want to go any more than that for the moment (until I get some more cash saved of course! )

Fishndude

The same set-up I have with a much milder cam would probably put you right at 400hp and it would be very streetable..

billla

Your budget would lead me towards a cam swap and heads - doing either without the other is not going to give you a combination that works well.

The E-streets are a fine choice, although you may want to look at iron heads given your budget. Selection of a relatively thin head gasket you can get the compression in a reasonable range - you really don't need to worry too much about detonation until you get up past 9.5:1 with premium gas. I don't think you can get to 400 flywheel horsepower with that budget and shortblock, but you can sure get up around 360 or so with a good .475 lift cam and the right heads.

I've DesktopDyno'd a bunch of L-48 build-ups if you search my post and L-48s. I can take a shot at a few for you tonight if you'd like.

billla

Can you share the specs on the cam and the dyno sheet? Not questioning your results...but if that was on a chassis dyno those are very impressive numbers for a relatively mild 355...