Team Camaro Tech banner

1 - 20 of 42 Posts

·
Registered
Joined
·
52 Posts
Discussion Starter #1
Hi, looking to upgrade the stock cylinder heads on the 327. I purchased edelbrock RPM manifold and CAM kit a few years back along with edelbrock 600 cfm carb (have not installed yet) and would like to get cylinder heads to match.

Edelbrock lists both 64cc and 70cc with straight or angled plugs. I don't know enough to make sense of the numbers to see what would be best.

Basically, I'm looking for a street cruiser with a little giddy-up to take on the occasional mustang.

A quick search shows a few comparisons vs other mfg, but I'd like to stick all edelbrock unless there is a compelling reason to switch.

Thanks for the help.
 

·
Registered
Joined
·
2,182 Posts
Since you want to stick with all Edelbrock I'd go with the straight plug 64cc RPM heads. They're a good match for a 327.

Mark
 

·
Registered
Joined
·
3,934 Posts
I recommend the 68-69 64cc 291 castings. You can easily put in 2.02/1.6 valves in them; however, the later 64 cc 69/70 casting has the Alternator Mounting Boss and much easier to position the Alternator tightly by using the later belt arrangement.

Then again considering the cost of rebuilding the old casting go for a set of Edelbrock RPM Alu- Heads and 0-Deck the Block.
 

·
Banned
Joined
·
3,193 Posts
The edelbrock E-Tec 170's would work the best for a mild build.

Edelbrock says these heads outflow the performer rpm by 17%. You'll need to get a vortec intake to match.
 

·
Registered
Joined
·
52 Posts
Discussion Starter #5 (Edited)
OK, so choices are:
Performer RPM - 64cc with straight plugs @ $559 each - or -
Performer RPM E-Tec 170 64cc straight plugs @ $589.

With the e-tec, I need a new intake since they are newer style. (~$250)

Cost difference is about $300. Not too bad if the performance is much better.
What about other issues like mounting locations for accessory brackets and such? Is that something to be concerned about?

I can't get through to edelbrock tech support due to "extremely high call volume"
 

·
Premium Member
Joined
·
4,680 Posts
Chris, I would probably go with the E-Tec heads and the new intake. You can always sell the new RPM intake you have to help offset the cost of the new one.

Ron, this is an honest question. I know the BEST way would be to zero deck the block, but with the extra thick 5/8" thick deck on the E-Tec heads do you think he can get by without zero decking? I think with the correct head gasket he should be OK?
 

·
Registered
Joined
·
52 Posts
Discussion Starter #7
OK. Spoke with Edelbrock. They agree E-tec's are the way to go. Much better flow and high-rpm performance.
He did warn against decking the block as I may run into clearance issues with the intake manifold if I do this. Also, I'm not looking to bring up the compression too much.

They claim you can see 363HP with this set-up from a 350, so I would guess around 325HP from the 327. That should be good enough for me :)
 

·
Registered
Joined
·
223 Posts
You can get these with free shipping though streetsideauto.com plus save an additional 5% with code Edelbrock2011 or save $75 using code QUICK75
Don't forget to have them match Summit's price.
 

·
Registered
Joined
·
3,934 Posts
You have already read my recommendations but you can't beat a Stock Old School 8000rpm 327 with 291 Heads or choose the forum recommendation for Edelbrock Alu-RPM Heads - It's Up to You - Which I agree with.





Other then Jenkins, I can COKE a Stock 327 to pull Strong through to 8000rpm pushing 425+Hp and don't give a SH*T - Other then Old School is Expensive today & the Mill remains OEM.

Gotta LOVE the 327 - Beware Hemi's & BBC's: Because I will Run Any Time :eek:
 

·
Registered
Joined
·
52 Posts
Discussion Starter #11
8000 RPM !! I though that was 302 territory only. That's a nice job you did on your engine.

I just checked my heads are the #3917293 heads (1.72 intake valves, 1.5 exhaust, 75cc chambers) :( They have got to go. (on a shelf that is with the other oem stuff).
I like the idea of staying period correct with the 291 heads, but I dont know where to find them or have them ported and done up like yours. Are they readily available?
 

·
Registered
Joined
·
3,842 Posts
I would def. go with a 64cc or smaller chamber, to get too much compression you'd need a 49cc head and almost a zero deck.
I'd call edelbrock and see if they don't already have any 58cc or 49cc heads in stock for the E-tec. I'm only at 10.8:1 on my 333" and thats with a 58cc head, .015" deck height and .025" head gasket.
You'll pick up lots of power just in the compression ratio change, I'd use a .015" or .025" head gasket it a .040-.060 bore to bump up the compression.
 

·
Registered
Joined
·
52 Posts
Discussion Starter #13
When asked what would be better (RPM vs e-tec 170) I got this response from Summit tech department ...


Hello,
It really depends on the profile of the cam you are running. The E-tec likely will be a better match for your 327 due to the smaller runner size (170 cc) if you are using a cam that does not exceed 5,500 rpm. But if you are more in the range of 6,500 - 7,000 rpm, the RPM series head (185 cc) would be the better choice. Both are very good heads and will work well in comparison to a stock head. But if you are looking to optimize usable engine HP, the cam profile will be critical to making a selection. Thanks, Mike

Since I'm running the RPM cam (good the 6500) could the older style RPM heads be better? Does this make sense?
 

·
Registered
Joined
·
3,842 Posts
What are the specs on the cam?
I'd personally go with the E-tecs.
Little motors need all of the velocity they can get, yes, you need to match parts, but big cam, intake, and huger runners will not work well with a small ci motor that spends 99% of it's life from idle to cruise with the occasional 6k run.

What rear end gears are you running, and is it going to keep the 3spd?
 

·
Registered
Joined
·
52 Posts
Discussion Starter #15
What are the specs on the cam?

What rear end gears are you running, and is it going to keep the 3spd?
Cam is: Duration 308/318, Lift .488/.510
http://www.summitracing.com/parts/EDL-7102/

3 spd is gone. Right now I have M20 4 spd, and 3.08 gears. Hopefully that will someday change to Keisler RS600 and 3.45 gears.

From what I heard here, I was leaning towards the e-tec 170, but this guy threw me a curve. If it gains me 20-30hp then its well worth the extra $ switching over the intake. If not, its certainly easier for me to just go with RPM's. I don't want to make this into a monumental issue, just want to get the best / right part for my hard earned $$.
 

·
Registered
Joined
·
3,934 Posts
I like the idea of staying period correct with the 291 heads, but I dont know where to find them or have them ported and done up like yours. Are they readily available?
Forget about anyone having the knowledge or willing to put that much work and money into an 8000 rpm 11:1 Static 327 sporting 291 heads today.

If you want 425hp and 8000 rpm out of a 327 with OEM Heads (291), I recommend you find a Forged 68 Crank and use the 4 bolt 010 block - only because you can mount the Vette Windage-Tray - Then purchase Eagle or Scat Rods with Forged Speed Pro Pistons but then you're cheaper going aftermarket Alu-Heads and 0-Decking.

Old School is an Expensive and Lost Art today. It takes months and humongous money, referencing Jenkins, to machine 291's to flow a 327 to 8G's but man the 302 did it naturally with them heads as stock simply because the displacement was smaller, but the 302 an 327 with 291's is Stock OEM - I do not recommend 291's for a Hi-Winding 350 and when I say Hi-Winding, I referring to 7000 rpm+ small cube mouse breaching 8G's putting out at least 425 Hp ;o)

Definitely not a Street friendly Engine but it can be done. We did it, over 40 years ago running aftermarket springs and SFT Cams made by Sigerson. Crower and Crane.

Nothing like seeing an 8G 327 DANCE to the Launch Line against an idling BBC, BBFE or Hemi and the WIN is a 50/50 Ticket with Stock Castings.
 

·
Registered
Joined
·
3,842 Posts
I've got 190cc heads with a similar cam 236* @.050 and .490" lift 110lsa in a 327
It runs strong from 3k up BUT I've also got 10.8:1 compression. Vacuum is nowhere near the 10-15" that edelbrock lists, and with the 3.08 gears my clutch is gone with the wind after only a few thousand miles, 3 tops. It makes good hp/tq but it really needs gears and more compression that I've currently got. If I had to do it over, i'd choose smaller runner heads, bump the compression, run a tad less duration on a 112* lsa and have much more valve lift.

RPM or E-tecs are good, I don't know what 15cc's will to do velocity/hp...
 

·
Registered
Joined
·
663 Posts
I purchased edelbrock RPM manifold and CAM kit a few years back along with edelbrock 600 cfm carb (have not installed yet) and would like to get cylinder heads to match.
Since nobody else has mentioned it -- Which Edelbrock cam kit do you have -- the "Performer" or the "Performer RPM"? The Performer RPM isn't that highly regarded around here and I'd think it would be a bit much on a 327...
 

·
Registered
Joined
·
52 Posts
Discussion Starter #20
Since nobody else has mentioned it -- Which Edelbrock cam kit do you have -- the "Performer" or the "Performer RPM"? The Performer RPM isn't that highly regarded around here and I'd think it would be a bit much on a 327...
It's the RPM.
Cam is: Duration 308/318, Lift .488/.510
http://www.summitracing.com/parts/EDL-7102/

Perhaps I should rethink that now too??? :(

Here's the goal: Stick with 327, get 300HP.
 
1 - 20 of 42 Posts
Top