I am currently having a pair of 781 ovalport/open chamber heads being prepared for my small cube bbc. Racer1320 has given me alot of advice on what work to have done. I was hoping to have the heads back today, but my engine builder was struggling with getting the seat & open pressure to Comp Cams specifications. He will need a few days more to sort out the solution.

It was my intention with this post to share with everyone here the parts used, modifications & machining performed, and also the costs involved from start to finish. I am also hoping to have some basic flow #'s to share as well.

Once I have the heads in my hands, I will post all the information here.

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

Todd,
Great, I'd like to hear what was involved in case I decide to swap my squares for ovals. What made you decide on the 781 oval/open castings anyway? What did you pay for the heads initially?

Jim R.

------------------
My 70 Chevelle (http://www.angelfire.com/pa4/jim/)

I needed to stay with open chamger heads as my shortblock has custom Venolia O/C pistons. The 781 and 049 are the best open chamber oval port heads from what I was told. I happened to stumble on the 781's a fellow had who was an hours drive from my house so I could save the $70-80 shipping costs from anywhere further away. We made a parts trade, but basically I have $150 invested in the bare castings. I have seen 781 & 049 oval port heads for sale for anywhere from $100 to 350 for a pair. They seem to be plenty available on the net, just none close to where I live.

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

[This message has been edited by Todd Geisler (edited 01-04-2001).]

I'll go ahead and toss in my figures as well.

Heads = $75 (all rusty and missing valves)

New stuff,
2.19/1.88 Valves = $55.00 (yes all 18!)
Comp springs = $250

Labor done,
Hot tank/primer, 3 angle valve job, Bowl blending, "some exhaust opening" (as he put it), Some deburing on the runners, but not gasket matching. Assembly also.

Labor = $600 (he is the best guy in town, so good that he has very little competition! and I went during the "busy season"

That makes a grand total of $980

-Looking forward to those #s Todd!!


------------------
BB414, TH400, 3.73 posi,
13.1sec @ 105 MPH (TH400 needs clutch pack, Radial T/As = zero traction)
"I've seen sunny days that I thought would never end " J.T.
Picture of me roasting the tires and other guy stuff (http://www.auburnextremeracing.org/drivers/mike/)
Video of me staging (smoke of course) (http://www.notabusinessracing.org/videos/mike_chevelle_burnout.avi)

18 valves??? LOL!

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

[This message has been edited by Todd Geisler (edited 01-04-2001).]

Mike,
Is that your real e-mail address in your profile? In a previous post (it is closed now), you asked me what my MPH was on the 13.0 run. It was 105. I was just going to e-mail you, but I couldn't stop laughing. That can't be real, can it. Oh, and thank you for the compliment on the car. It was a lot of hard work to get it to look like that. The car was previously white/black stripes with rusted quarters.

JR

ps...I called Summit, they are out of stock on the "18 valve" pairs of heads http://www.chevelles.com/forum/smile.gif
------------------
My 70 Chevelle (http://www.angelfire.com/pa4/jim/)

[This message has been edited by Epistuff (edited 01-04-2001).]

Todd,
are you getting the heads ported as well as the regular 3 angle valve job? I am looking forward to the actual costs of getting this done.

------------------
Dave (NY)
70 chevelle ss396 conv
66 chevelle ss396 hdp/conv
72 chevelle
55 chevy prostreet
69/71 camaros
61 impala bubbletop
TC member #493

For what its worth....I bought a set of Holley aluminum (42lbs each) complete (minus studs and guideplates) 310cc heads with 2.25/1.88 stainless steel valves, 11/32 bronze valve guides, valve springs with 135# seat pressure and 345# open, 3 angle valve job, .600 raised D port exhaust heads for 1150 bucks for the pair brand new.
I have a set of 781 oval ports in my garage that would have cost that or more after installing new seats, guides, springs, grinding for bigger valves, and the valves themselves. The rectangular ports arent my first choice but for that price and the fact that on the Edelbrock Power package system...the oval and rectangular port dyno charts were virtual clones of each other....it seemed like a no brainer to me. This is why I chose the rectangular port heads...I truly dont think they make any more power than a decent oval port head...but according to Edelbrocks dyno they certainly dont make any less. Maybe the aftermarkets are different than original GM castings and thats why there is such little difference but who knows...I am sure the debate will rage forever.

Todd are you the same Todd that had a Malibu in one of the magazines with a caption about leaving like a shark? That was a pretty wild picture...I saw it during XMas when I went home to visit the parents...found a bunch of old car magazines in a box under the bed. Anyways......winter sucks. http://www.chevelles.com/forum/frown.gif I am sick of buying parts...I want to buy some entry fees.

------------------
Bill
65 SS
Team Member 1013

I guess you could say porting, but it will be mild. A throat cut was made below the valve seat to open it up for the larger valves. The cut will be blended into the port, the intake opening blended to the gasket, and the roof raised slightly. He might also do some other grinding wg=here he feels necessary. The valve job is a 5 angle performed on a Serdi.

I basically told him what I wanted to accomplish power/ET wise, and let him make the porting decisions. Basically we are doing the most cost effective mods without spending a ton of money on porting that might gain little in performance.

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

I bought a set all ready to go for $600, so I thought. they looked new, cut for 2.19-1.88 valves comp cams valvetrain thruout. well 4 intakes were real thin, so $400 later I'm good to go. I had him replace all 16 valves and do a new valve job. the heads had been cc'd also. even if they looked new you can still get took. i owe him one.

------------------
1969 SS 396

5 angle valve job! WOW! It's starting to sound like the 70s when they were dong "radius" valve seats, an infinite numbers of angles that blended to form a radius seat, useless but very nice looking.

I can't imagine what the other two cuts would be for a street car. I'm familiar with the Serdi seat and guide machine and the tooling it uses. I'm not a fan of carbide cutters, learned on stones and prefer them. I like the finish on the seat a stone leaves, it grinds the seat rather than cutting it.

I would be interested in what the 5 angles are. One would hope the is a 45 seat cut, 60 bottom cut and a 30 top. If you have the room you can put on a 15 over the 30 but that last one eludes me.

I'm doing a set of 049, the way things are going I might finish them this year!

------------------
Wally
www.muncie4speed.com (http://www.muncie4speed.com)
Gold #67
2001 Chevy Silverado LT
67 Malibu "Small Block" second owner
90 SS454
71 Malibu "Small Block"

[This message has been edited by Wally (edited 01-04-2001).]

Bill, nope that wasn't me...if it was, I would be much faster than I currently am http://www.chevelles.com/forum/biggrin.gif

Ratuned, that is one of the hassles I was trying to avoid. In the past I have always bought other peoples problems and wanted to start fresh this time. it may cost me more, but I knwo what I have will fit my needs exactly.

Wally, Don't quote me on the 5 angle job, but that is what a good friend of mine that is best friends with the engine builder told me he uses. I will know all the facts (or at least most) when I get them back. BTW, currently my car cannot be considered a street car...race only for now.

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

[This message has been edited by Todd Geisler (edited 01-04-2001).]

[This message has been edited by Todd Geisler (edited 01-04-2001).]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Todd Geisler:
18 valves??? LOL!

<HR></BLOCKQUOTE>


That is pretty funny huh. Guess the 1.88 thing got me going. We all know it should be 24, or 16... yeah 16, that's the ticket

Bill - those Holley heads sound like a great deal. Did you buy those from a retailer or someone trying to unload them http://www.chevelles.com/forum/smile.gif ? Do you know any flow #s on them? I found some at
http://www.nastyz28.com/2gcog/cylhead.html

but it doesn't list lifts and has no detail, I'm not even sure it's the same heads.

Rob

Sorry I haven't posted the results since starting this thread. I just spoke with the machine shop again today and he has the one head done. The other needs the exhaust spring pockets cut .040" down since the heads are of different date codes and machined a little different. I should have them back by the end of this week, and will post the costes involved, etc. then.

I needed to give him the time he needs so the heads are done right. I suppose good work doesn't come cheap or quick. I would bet Bill K could agree with that statement http://www.chevelles.com/forum/smile.gif

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

Todd,
Yes, give an update when it is finished. I would also like to know what heads you originally had before the swap??

Jim

------------------
My 70 Chevelle (http://www.angelfire.com/pa4/jim/)

Ok, I just got the heads home from the machine shop this afternoon. Here is a break-down of the parts & labor expenses.

PARTS:
bare 781 head castings $150.00
2.19/1.88 SS valves (11/32" stem) 159.20
Comp Cams Titanium retainers 142.66
Comp Cams 939-16 springs 147.26
Comp Cams machined keepers 25.35
PC seals 24.00
exhaust rotator spacers 28.15
Comp Cams guides plates 46.35
ARP rocker arm studs 56.15

Total parts $779.12

LABOR:
magnaflux castings $ 24.00
cast iron guide (1 was cracked) 15.00
bronze guides including liners 116.00
surface heads 52.00
machine for PC seals 24.00
bowl blend/pocket port 95.00
port match heads & intake 120.00
measure combustion chamber CC's 30.00
competition valve job 150.00

Total labor $626.00

Total parts & labor $1405.12

The flow bench work was included in the work that was performed. The valve job is a 3 angle (30/45/70 degree cuts) and the bottom 70 degree cut was followed by a radius that then blended into the bowl. The valves both had a 45 degree seat with a 70 degree back cut done on them. We wound up having to install +.050" keepers to get the seat & open spring pressures where Comp Cams recommended. Since the heads were different date codes, the installed heights were slightly different from one to the other head. The one head had to have .040" removed from the exhaust spring pocket to equal everything out.

The flow figures were as follows:

INTAKE

.100" 71.00cfm
.150 106.89
.200 132.19
.300 192.26
.400 224.51
.500 231.87
.600 239.01
.700 252.68
.800 265.64

EXHAUST

.100" 65.45cfm
.150 90.61
.200 113.37
.300 142.65
.400 165.80
.500 183.19
.600 188.94
.700 206.98
.800 206.98

I was not terribly surprised by these flow figures. The flow bench is a JKM, and my engine builder claims that bench is more conservative than the Superflow bench. he has been told the Superflow will show about 15 cfm more than the JKM in identical tests. I suppose that is also why most manufacturers use a Superflow bench? What I don't know is if the intake port was a good or bad port that was flowed.

One last thing...the combustion chambers CC'd out to be 115 cc's.


------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

[This message has been edited by Todd Geisler (edited 01-12-2001).]

While it's hard to directly cross-reference numbers...4.28" bore 2.25/1.88 raceflow valves...merlin cast iron oval port.

@0.500 316/232 cfm
@0.600 342/? cfm
@0.650 354/271 cfm
@0.800 ?/287 cfm

These figures were given to me today - from the short (bad) intake runner and a 2" exhaust extension - after a full port.(more of an update on the work being done - going into the Dart manifold later next week)

After this the last few % to be found in these heads "would have taken as long as the first 90%"

All work done without significant change to the runner cross section area (to preserve torque).

I believe stockers go 300/200 @ 0.600. These heads may be worth consideration if someone is following this thread and doesn't have a core to start with.

MAT

This is just my opinion, but I think it is near impossible to compare flow #'s from different benches, different atmospheric conditions, etc. There are way too many vairiables.

Herer are the flow #'s that Chevy High Performance listed in their BBC Flow to go head tests. These are 049 heads, but should be very comparable to the 781. These were also flowed with the stock size 2.07/1.73 small valves with a standard single cut valve job.

lift...Intake...exhaust
.100 59 52
.200 124 96
.300 188 123
.400 232 143
.500 250 166
.600 264 173
.700 264 174
.800 265 173

Also, their test was performed on the SF-600 Superflow bench.

Oh yea, I know of stock oval port heads that have gone in excess of 300/225 cfm...with alot of grinding.
------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

[This message has been edited by Todd Geisler (edited 01-12-2001).]

Todd, thanks for the update. I have been following this post. What heads do you currently have? I am interested in knowing what your car ran with whatever the old heads were compared to how it runs with these new oval port heads. I assume you had rect. ports? If so, what casting? Do you plan on making any other mods when you install the new heads?
Thanks and good luck,
Jim R.


------------------
My 70 Chevelle (http://www.angelfire.com/pa4/jim/)

Hey Jim,

The old heads I ran were fully ported GM 990 castings with 2.25/1.90 valves. The NHRA rated the intakes at 323cc in stock form and mine were ported quite a bit so I expect my intake ports were 325 to 330 cc. Those heads flowed 325/250 @ .800 from what I rememeber...I didn't keep a copy of the flow sheets when I sold them.

I also have changed the cam. My old grind was a Crane inverted roller with .712 I&E, 272/278 @ .050, and 312/316 gross on a 110 lsa. The old intake was an Edelbrock 454R with a Pro-Systems 1100 cfm dominator.

The new cam is a Comp Cams Extreme Energy XR286. This cam has .653/.660" lift, 248/254 @ .050 and 286/292 gross duration on a 110 lsa. The new intake is a Victor Jr. oval port and the new carb is a borrowed 850 race Holley prepped by Brad Urban's carb shop years ago.

That is all the changes for this season which is a large amount in itself. I am quite hoepful in how the performance will improve. My converter may be a problem as it was slipping almost 11% last year and will probably slip even more with the added torque the oval port induction should add. The converter will ahev to wait for a while due to money constraints.

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

Opps - sorry Todd - meant stocker merlins go 300/200 out of the box.

MAT

Anyone know where to find those Holley heads? I've been looking around, nobody has em.

Rob

Todd, good job. Looks like his price is about the same as Rich's.

I wouldn't be concern about the appearance of "low" peak flow numbers. As you know low lift flow while maintaining a high velocity port is what your after anyway. You are correct though that flow benches like dynos differ in results.

I'm guessing my ovals flow about 305cfm at peak lift. I arrived at this using my simulation programs and backing into the HP/Torque numbers I needed to run the ET's that I do. I figured the larger 2.25 intake valve to be worth 5% and that predicted increase in HP was right on the money with my actual ET's. The purpose for the larger intake valve was to achieve greater low lift flow which I believe we have.

BTW, I used 290cfm for my predictions on your ET's/HP.

Now get those heads bolted on, button everything up and make some 10 second passes. Remember that I'm planning to be at Atco on Sunday 2/18 and 2/25 if you can make it.

I'm going to plop this back on top - it feeds well with the new thread re: oval port buildup.

MAT

Anyone know where to get those Holley heads for $1150 !? Bill! Where did you go?

Here's some flow #s for Canfields alum rec port heads (305 cc, 2.25/1.88). Competition Products sells these complete for $1399:

FLOW@.100: 75 / 61 FLOW@.200: 161 / 115
FLOW@.300: 215 / 163
FLOW@.400: 257 / 199
FLOW@.500: 303 / 228
FLOW@.600: 328 / 251
FLOW@.700: 339 / 265
FLOW@.800: 332 / 273

BTW the guy at Competition Products says the Holley heads are Canfield castings.

Rob

The old Holley heads are Canfield castings. The new BBC heads are proprietary Holley designs including new Oval Ports.

Todd:

Saw you ended up with about $1400 into the heads. Do you have any flow numbers for out-of-the-box Edelbrock "roval" aluminum BBC heads. I remember seeing them for about $1700 somewhere. I'm wondering how they stack up. Does the extra $300 for Edelbrock's get you anything more than just a weight savings?

Hey Greg,

Edelbrock posts flow data on their site. You cannot compare flow #'s from different benches though. My heads were flowed on a very conservative bench.

Also, the components used on the factory (Edelbrock or GMPP) assembled heads are not of the same quality. I used the best parts I could get. Titanuim retainers are over double the cost of steel, roller springs cost about double of flat tappet springs, and ARP Pro series studs & Comp Cams guide plates ran the cost up. Using a lesser quality valve (in line with the Edelbrocks) in addition to standard quality components would easily lower the total to about $1000-1200.

Also keep in mind the Edelbrocks have a port volume of 290cc which is closer to a small rectangular port head than a factory oval. In my application, I felt the GM head fit my combination and intended usage.

------------------
Todd Geisler
79 Malibu
11.16@125.8mph
Malibu Muscle
http://www.MalibuMuscle.cjb.net

[This message has been edited by Todd Geisler (edited 01-26-2001).]

hi todd read your thread and would like to let you know that i ran the #049 with 2.19 int. & 1.88 exh and pocket ported the heads myself matching each runner cc'd. i blocked off the cross over and openedthe intake 1.810 x 2.085 and exh. 2.00" pockets int. 2.00 & exh. 1.700. my car ran fine on street and strip. have done cruises 175 miles plus and have run 10.7's/126 at the track. pyrometer readings were on the money at track and plug clouration right on.
i've since got a set of edelbrock heads and have been doing some porting with the assistance of edelbrock online. they've advised me where and how much and at what locations to port. i hope to better my times?
the #049 were the pick of choice for John Lingenfelter. the flow and volumne characteristics were a bit better then the #781 but comparable. #049 was 256cc int & 120cc exh. edel #6045 int 290cc 309 cfm & exh 110 cc 218 cfm out of the box.
i've been running with comp cam solid roller steel retainers, edel street tunnel ram with 1300 cfm carbs, 454 + .030.
hope you have lots of fun and keep rolling.
andy

Whats stock 1974/5, P/U, -781 head's intake port cc volume. Just outa curiousity, want to compare to the oval port Merlins cc volumes. Thx. pdq67

Help Guys as port flow # do not mean alot to me , guess my question would be with the over size valves and work Todd is speaking of would they suport say running 6500 rpm and 500 or more HP?? guess I will have to punch some cam ## and flow # in my comp cams "cam quest" program and try and learn have a set of 046# and am trying to figure out to do em up or ... looks like I am not the only one with that question

thanks Joel

Man where did you dig this post up from. I can tell you valve train parts have went up a buuunch since this was written. Oval port heads can make close to 700 h.p. if you spend some money on the port work. Mine flowed enough to make 680 according to the theorys. Made 666 at 6500.

would they support say running 6500 rpm and 500 HP??

thanks Joel


:yes: --- :beers:

I used to have a 69 Camaro, 505ci, 3700 LB, 950 HP. stealth intake. full exaust street car. I had a set of Edelbrock roval heads out of the box. drove to the track. added stickies in the back. ran 10.50's @ 129. I like those heads. I would buy them again. I'm not a pro racer, just wanted to have a little fun. I'm sure someone who knew what they are doing could have made this thing go even better. just praising the potential of those heads.

I got half way through the 2nd page when I realized this was 9 years old. You would be better off starting a new thread instead of digging up one like this with very old information. Things have changed in 9 years.

My god, $1400 plus for those heads is pretty steep. For that kind of money i would have spent a little more and went aftermarket. Should have been under $1000.

I am not sure the prices have changed too much. I just finished up a set of 049's for my 1971 Monte Carlo. All new parts (including guides). I ported them a little myself, but did pay extra to have the throat and chamber relieved when the new valves were installed. Just about $1200 when it was all said and done.

To bad everyone is so far away. I'd have saved you about $400 for the same thing.

where you at any way FRYNTYR? I am close to the spokane area. Looks like u are in the NW? u work in a machine shop or just know a good one?
Joel

where you at any way FRYNTYR? I am close to the spokane area. Looks like u are in the NW? u work in a machine shop or just know a good one?
Joel

By Everett. Machine Shop is about 40ft from my house. :D

By Everett. Machine Shop is about 40ft from my house. :D

cool u might now some of my friends even shane -442 ranch black vista cruzer or Jim D so u the guy to do up some head s , rods - blocks up through? have friends going back and forth often and in 6 hours I can b there just a nice sunday drive with those 4:11 gears lol :beers:

cool u might now some of my friends even shane -442 ranch black vista cruzer or Jim D so u the guy to do up some head s , rods - blocks up through? have friends going back and forth often and in 6 hours I can b there just a nice sunday drive with those 4:11 gears lol :beers:

Good ol Jim D,,,, oh ya, Know him well. Pretty good friends with him.

Ya, I do alot of work but with time constraints I stay away from full engine builds. Mainly just do all the machine work to save the regular guy that likes to do their own assembly and save a guy some money because I know how crazy labor prices are. I have a regular job to pay the morgage and all my machinery is paid for so overhead is low.

Good ol Jim D,,,, oh ya, Know him well. Pretty good friends with him.

Ya, I do alot of work but with time constraints I stay away from full engine builds. Mainly just do all the machine work to save the regular guy that likes to do their own assembly and save a guy some money because I know how crazy labor prices are. I have a regular job to pay the morgage and all my machinery is paid for so overhead is low.


I have a machinist like that, God Bless both of you!

I take him the part I need machined with a list of what I want done, all ready cleaned and ready to go and I usually save about 70% of what everyone else pays at local shops- and he does some pretty damn good work too.

Only place I know that I can take two rusted chucks of metal and walk out with them cleaned, milled rocker stud bosses (I pull and tap them myself), surfaced, and a good 3 angle VJ for $150 a set.

Most of the machinists in here will laugh a customer out for that price.