Which Heads?

[Brass]

Some rambling questions about heads...  I want to wring more power out of a 72 low comp 440.  It seems the E-street 5090 heads would do two things at once: raise compression and flow better than the 906's.  Seemingly a good match.  Yet I hesitate because Edelbrock is billing them as "entry level" or whatever that means.  They go on to indicate these heads are appropriate for up to about 5,500 rpm.  Does that mean power falls off a cliff at 5500?   My cam has a range up to 6,000 rpm with redline at 6,500. 

The E-Street heads have to be a significant step up from the 906's, right?   Oddly, Edelbrock just doesn't seem to be interested in marketing these heads.  It's weird.

BTW: I wouldn't mind going with the RPM heads with better hardware but the smallest chamber they offer is 84 cc, as opposed to the E-Street's 75 cc.  Alternatively, the Victor (and Pro-comp) heads would bump compression too but they require offset rockers, and I've read that they may actually hurt performance in anything that isn't a full on race engine.  Then there are the Stealths but they seem to require more work out of the box.   I suppose I could get the Stealths milled from 80 cc to 75 cc with some other minor work...

I'm not ready to do a full rebuild at this point but I would like room to grow.  It'd be nice to reuse whatever heads I get when the time comes.  But for now, if the pistons are .080 in the hole (a guess), compression calculators are telling me 10.09:1 static compression is possible with a 75 cc chamber and .020 shim gasket.

Also, any guesses as to what kind of power this combo should be capable of with a head change?  Crower 282 HDP (112* LSA.  Dur: 282/292 .478/.502.  Dur @.050: 228/236 .319/.334) , orange box, mechanical 700 Holley, CH4B.  HP manifolds  for now – headers probably next.

Thanks – I'd appreciate the input.

[cdr]

440 Source
From now until Friday at 5PM, order a set of Super Stealth heads and we'll throw in our 200-1125 .650" offset aluminum roller rockers at NO CHARGE. Thats a $300 value for FREE!! Ask for Kim. This deal is available on the phone only, not available on our web store. While supplies last only!   with these you need to buy valves ,springs,locks,retainers & seals,but all still a great price

[Brass]

Good deal, perhaps - but aren't those overkill for my combo?  Cost of the hardware will add up quickly.

[FLG]

I wouldnt trust 440 roller rockers on a stock motor, let alone any performance build.


Best thing is to find out what pistons you have and how much in the hole they are, then go from there.

[Cooter]

I don't know bout 10:1 with pistons that far in the hole. Might do it, but I'm thinking more along the lines of around a 8.5:1-8.8:1 440 as is with open chamber heads, and around 9.5:1 with closed chamber iron heads with steel shim gasket. Keep in mind, with aluiminum heads, you most likely need to run the Cometic (Multi-layer) gasket which is NOT .020 thick. more like .045 thick.

[Brass]

Thanks for the comments.  The slugs are original to the engine.  I don't have a piston to deck measurement yet.  But in any case, the closed, 75 cc chamber should yield the biggest compression bump.  Especially if I can't use a shim gasket.  I'm still leaning toward the Edelbrock E-Streets as the best option for better flow and compression - at a reasonable price...  I just wish people had some experience/opinions to report.  They seem to be ideal for my combo but there's a total dearth of testimony since they've been on the market.

[chargervic]

With a 75 cc head and a .040 gasket and .080 deck height your CR will be approx 9.6. BUT  I have seen lots of those low compression 440's with the piston down .150" . This will give you about 8.5 with the same head & gasket. I special ordered Cometics at .027" and they built them but I was told they wouldn't do it again. No problems so far. FOR SURE do NOT use 440 Source aluminum rockers on anything but a display shelf. Their geometry is totally out to lunch and the quality is extremely poor. However, the Stealth heads are okay with minor port work and vacuum testing. My set had one seat not installed properly, but 440 Source paid the bill to have it fixed locally. I make 515 HP and 600 lb/ft with a 451 using these heads, shifting at 5000 RPM.

[Cooter]

Brass, I can give you a pretty good idea what a buddies RR did with one of my mild 440 builds with a 4-speed.

Engine was a Stock block 440 .030.
Pistons were replacement 4 eyebrow.
Cam .480 In. .474 Ex. 225 In. 220 Ex. @ .050 with 110 LSA
valves were 2.08 In. 1.74 Ex. Ported "516" heads. (Closed Ch.)
Pistons were around .018 in the hole for "Zero" deck block.
Intake was Torker Single plane with Eddy. carb
Headers were Hooker Super Comp.
3: Exhaust and Dynomax mufflers.
On the chassis Dyno it put down 350 HP and 480 Ft. Lbs of torque to the rear wheels on pump fuel.

[Challenger340]

Just my thoughts as it relates to your original questions.
It would seem that you are trying to cover many bases with one purchase, that being to realize the best improvement now, but still have useable parts for a later engine upgrade.
No easy task, given that many of the criterion to "best" selection for the current Engine, will undoubtedly compromise "best" for later re-use on the next Engine build.

The current Engine lacks Cylinder Pressure pure & simple, and you are correct in addressing this most important factor as best you can in this Head purchase,
especially,
since the problem is compounded by the late closing point in your Cam, around 38-40* ABDC on ther Crower 228* @ .050 Duration.

The E-Street Heads would offer a significant, although not perfect, improvement in the Compression area. Really, plus 10.0:1 should be your target C.R. when switching to an Aluminum Head.
The E-Street heads would also maintain good port velocity by default of the lower port volume, which can maintain broader Torque curve numbers.

Regarding the Crower HDP 282, forget the advertised 6000 rpm, little lown the 6500 redline.....even with headers and better stuff on this, or, the next Engine.
Peak power will be reached at 55-5600 rpm on the 112 lsa, so forget about revving higher thinking you'll go faster...just ain't happening.
On the current Engine with manifolds...52-5300 and Shift, even with the E-Streets.
Far too many reasons to get into here, suffice to say, go to a Dyno if you don't believe me, remember where you heard this first later.
Really,
if this is a stock '72 bottom end currently.....much past 52-5300 rpm on a regular basis is chancing things on 40 year old Rod bolts.

You don't say enough regarding your next Engine build, to make a valid assessment of the E-Street Heads compatibility for your goals.
suffice to say....
the E-Streets Flow capabilities are conduscive up to about 500hp ootb depending upon parts used.
IF......
and this is a BIG "IF"....you can get above 10:1 C.R. with the E-Streets, Headers, and a decent Intake Manifold on the HDP 282, you should see 450'ish HP, but again, this will occur mid 5,000's rpm, no more !

[Brass]

Thanks for the comments!  They really helped frame it for me.  For now, I think the best thing to do is work with what I have.  If I can get 400+ HP out of the stock bottom end by bolting on a set of E-Street heads and some headers, that will serve.  Its more than I have.  If I end up wanting more later, I'll revisit the whole recipe from scratch.  These cars are never done anyway, right?  The proven combo section certainly lends fertile ground for ideas.

Also, the peak is indeed somewhere just North of 5,000 right now.  So I believe you, Challenger340.  : )  I thought uncorking it might extend the range – but its good to know not to expect that.

[firefighter3931]

The 75cc E-street heads are a good option for now and into the future as well. 

The small chamber will bump up your static compression and the increased flow and port volume will indeed extend your power range. The engine is peaking low because the heads are the cork in the system, not the cam.    With better flowing heads you should see peak power @ 5500 or so. I've used that cam before and it peaked in the mid 5k range for me with a set of ported iron heads that didn't flow as well as an E-street/RPM casting....but much better than an untouched OEM casting.

The wide 112* lsa will extend the powerband vs a tight lobe profile but the torque curve will be more linear, that's how they are designed to work. 

In the future, should you decide to build a stroker you can allways order a piston with a larger dish to dial in the static compression where you need it to be. 

The E-street heads are basicly an RPM casting with powdered metal valve seats. The seats are a bit harder to machine but it's something any competent machine shop can handle should the need arise.


Ron

[Brass]

Thanks for the input, Ron!  One question: what should I ask the machinist to check/do with the E-streets before bolting them on?

[cdr]

CK GUIDE clearance,valve sealing,springs & install some good seals.

[firefighter3931]

Thanks for the input, Ron!  One question: what should I ask the machinist to check/do with the E-streets before bolting them on?

As Charlie (CDR) mentioned ; have the valve guide clearance checked. Have the valve sealing checked as well. Both areas could possibly need some attention. 

The hardware : springs/retainers/locks are very good quality and compatible with your cam so no need to swap any parts. 


Ron

[Brass]

A couple more questions, guys.  Since cam lift is under .510 will I need adjustable rockers or different pushrods?  If so, would there be a benefit to switching to 1.6 adjustable rockers?  Also, which NGK plug?  

By the way – I checked with Cometic and that seemed encouraging.  They will make custom, multi-layer head gaskets down to 0.027:  

http://www.cometic.com/custom-gaskets.aspx

[BIGBLCK11]

Were you still trying to go with the E-street heads?  Summit had a pre-order for 6 months, but as of last June, the part number was gone.  I called and had them inquire to Edelbrock, they said not enough interest and the part was not being made.  I had been waiting on them for the same reason, to boost my compression.  I wondered if you had some other info on them.  Edelbrock's site doesn't list them either.

[Brass]

The 5090's are still on Edelbrock's site:  http://www.edelbrock.com/automotive_new/mc/cylheads/chrysler/bb_estreet.shtml

Jeg's apparently has them but they're ~$600 more than Summit had them listed for.    http://www.jegs.com/i/Edelbrock/350/5090/10002/-1?utm_source=msn&utm_medium=cpc&utm_campaign=BingIDS_Edelbrock&Keyword=+Edelbrock%20+5090

[BIGBLCK11]

Ok, thanks.  I see them now.  Yeah, that is as much as the RPM heads.  I just called Summit, their info still shows unavailable to the sales rep.  But, he said to call Monday while Edelbrock is open and they will double-check.  I will post anything I find out on price.

[Brass]

FYI: Summit told me the 5090's are being discontinued so I called Edelbrock and spoke to Dave Stinson, the Tech Manager at x2820.  He confirmed that the 5090's are available, ready to be shipped today, and are not being discontinued by Edelbrock.  He is going to have their National Sales Manager call Summit directly and clear that up today. 

Assuming Summit re-lists them, it will be interesting to see what they set the price at.

[BIGBLCK11]

Yeah, I called Summit today.  The sales guy said he would try to have the part number reactivated.  But, he couldn't give me a price.  I wonder if part of it is due to the huge increase.  I did find them for $1199 online.  Jegs says they price match, so I may go that route, depending on what price Summit comes up with.  I will let you know if they do and post the link too.

[BIGBLCK11]

They have arrived!  I didn't bother with a price match.  I just ordered them direct from Performance Parts, out of TN.  I checked inventory prior to ordering online.  The guy was cool on the phone.  They had one set in stock, that shipped out of Florida.  It saved me $100 tax over Jegs too.  $1199.95 with FREE shipping.  $10.95 handling less a $5 first time buyer discount.  The order was processed Thursday, the heads were delivered Monday.  I will let you know if there are any issues, once I have them checked out at a shop.  Of course, I probably won't be able to take the car out for a few months.  We had a couple inches of snow, at 29 degrees today. 

http://performanceparts.com/part/Edelbrock/5090 

[Challenger340]

Them looks perdy

[Brass]

Good score!