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Old 11-14-2004 | 11:23 PM
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From: SYLVANIA,OHIO,USA
Car: 89 Formula
Big block heads

I need to find some heads for my 427 thats going in the camaro, is there any stock heads that I should look for or any that I should stay away from.
Thanks
Old 11-14-2004 | 11:40 PM
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From: Staunton,illinois
Car: 1966 impala , 1998 sebring vert,1978 buick regal turbo, 1991 chevy silverado 3/4ton 4x4 lifted
Engine: 283, 2.5,3.8 turbo 350
Transmission: powerglide,auto overdrive, th350,4L80
http://www.mortec.com/bbc.htm

check out that site they have a listing of about every bbc head ever made stock

give you an idea of what there is out there
Old 11-15-2004 | 06:34 AM
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From: Lima, OH
Car: '89 Formula 350 & '86 Z28
Engine: L98 & 355ci
Transmission: 700r4 in both
I dont know any specific casting numbers, but I would stay away from rectangle port heads and run oval ports. If your running on the street
Old 11-15-2004 | 01:40 PM
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Whats the difference between the oval and rectangular port heads?
Old 11-15-2004 | 02:33 PM
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From: Pueblo Co
Car: 1989 C4
Engine: L98
Transmission: 700r4
Axle/Gears: 307
Rec port heads flow more. I doubt any street engine would be reved high enough long enough to take full advantage them but if you had a blower on there
Do a quick search under 57kids name for ported BBC heads. He's running a common BBC "performance" heads that Ive used from time to time, I just cant remember the casting.

So is this a real TD 427 or a bored out SD 396/402?
Old 11-15-2004 | 02:46 PM
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Its a 454 block with the 427 crank.
Old 11-15-2004 | 03:45 PM
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From: Lima, OH
Car: '89 Formula 350 & '86 Z28
Engine: L98 & 355ci
Transmission: 700r4 in both
Plus oval ports are have much smaller intake runners, which makes for much better low end, and throttle response
Old 11-15-2004 | 05:02 PM
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From: Waterloo, Iowa
Car: 86 firebird with 98 firebird interi
Engine: pump gas 427sbc Dart Lil M 13.5:1
Transmission: Oldani TH400 w/ BTE 9" convertor
Axle/Gears: 31 spline Moser/full spool/4.11Rich
You want 781 cast heads, the best factory BBC out and can be worked over to provide excellent flow numbers.

336781.....73-85...oval...OPEN...454, 118cc chamber, 256/114cc ports

If interested I know a racer that had 2 sets he was letting go cheap, if I recall they were bare casting for $100/pair. I have'nt talked to him in awhile so they're probably gone by now. If interested pm me and I'll get ahold of him to see if he still has them.
Old 11-15-2004 | 06:28 PM
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Car: 89 Formula
I found a pair of 049 casting heads for $200 are they any good.

IHI- thanks for the info, im trying to find stuff locally, i know shipping would be alot for the heads, but thank you. If i cant find anything i will get back with ya.
Old 11-15-2004 | 07:58 PM
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From: Waterloo, Iowa
Car: 86 firebird with 98 firebird interi
Engine: pump gas 427sbc Dart Lil M 13.5:1
Transmission: Oldani TH400 w/ BTE 9" convertor
Axle/Gears: 31 spline Moser/full spool/4.11Rich
All my buddies switched over to BBC over the past few yrs and the 781 heads are all that they looked for until they found them. I dont have any idea about the other factory castings and how good they are, just know 781 is what everybody wants and what they're running high 9's low 10's on. The guy that's selling the 2 bare sets had his 781's flowed and they came back at 335cfm @28" which is amazing from a factory cast head and gives you an idea of what they are capable of. They're out there, so dont settle since heads are the #1 thing to make power with the cam following close second. My friend pulled his off an old suburban, took them to the shop and had'em worked over/freshen up. He had just at $460 in them and ran 11.34 on a stock bore 454 peanut hydraulic cam in a 3500lb car.

Whatever you do make sure you get 1 peice valves!!!! Cannot stress this enough!!!! If you go with any cam bigger than stock requiring higher spring rates it's only a matter of time before you will snap valves off, so do not save money in that department!! That same 454 I mentioned above lasted 2 races at the end of the '03 season and 1 race at the begining of this season and tore the whole motor up. He saved $30 by not getting 1 peice vavles and now needs a new block, 1 head, rotating assembly, and all the time and money for machine work/assembly.
Old 11-15-2004 | 08:02 PM
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From: north plainfield, nj
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Engine: 6.0L
Transmission: A4
i have a set of heads from my 454 that im not goin to use, there oval port heads with mild portin job. i got pics on my other computer, if u want i can email then to u and make me a price or PM me other wise there either goin to sit and wait or get junked.
Old 11-15-2004 | 11:17 PM
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Car: 89 Formula
IHI, who would you recommend for valves.

Timz2882- thanks for the offer, but im goign to try to find some around ohio first, i know shipping will be alot from NJ. If i cant find nothing you and IHI i will get ahold of.
Thank you
Old 11-16-2004 | 12:07 AM
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From: Waterloo, Iowa
Car: 86 firebird with 98 firebird interi
Engine: pump gas 427sbc Dart Lil M 13.5:1
Transmission: Oldani TH400 w/ BTE 9" convertor
Axle/Gears: 31 spline Moser/full spool/4.11Rich
For budget/reliablity Manley valves work very well. No need to get real exotic if it's going to be N/A.

p/n11528-1 2.18" intake vavles $12/ea.
p/n11527-1 1.88" exhaust vavles $12/ea.

Depending on cam profile and size a stud girdle is a wise idea given the poor geometryof the BBC head this will help durability as well as performance. If you can swing it titanium retainers area big help for that last bit of hp also.
Old 11-16-2004 | 11:02 AM
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From: SYLVANIA,OHIO,USA
Car: 89 Formula
I will be using the extreme energy 284 cam. 574, 578 lift, 240, 246 duration.

What do you think of the world products merlin heads.

Last edited by Duke901; 11-16-2004 at 11:05 AM.
Old 11-16-2004 | 02:08 PM
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From: Waterloo, Iowa
Car: 86 firebird with 98 firebird interi
Engine: pump gas 427sbc Dart Lil M 13.5:1
Transmission: Oldani TH400 w/ BTE 9" convertor
Axle/Gears: 31 spline Moser/full spool/4.11Rich
Looking at my book you must be talking about the Merlin II Oval port cast iron heads? 269cc runners 119cc chambers 2.30/2.88 vavles .600 max lift for $666.99?

The only thing that would have me asking questions to the company is the fact in the product description it advertises 1" rasied exhaust ports which might make for some extreme clearance issues on our cars...any many others for that fact.
In a nutsheel that would rasie the entire header up 1" over a factory location-improved flow yes, but at the expense of clearance issues when installing. Best bet would be to contact World Product and see if anybodies tried this on 3rd gens, or do some other reserach and see what you come up with.

They sound like an excellent head, would be curious to find some flow sheet data on them, I'm sure they've addressed getting more flow at lower lift which is critical, if so they soould like a great head.

Also curious about pricing, I assume that's per assembled head? If they are listing per head by inserting the term "ea." before the price, take a serious look at some other manufactuer aluminum heads which would not be far off the mark from the total for a pair of iron heads, but will allow you to add some more compression and reduced weight for more power Currently a buddy is pricing some 265 or 305 AFR heads set up for hydraulic or solid flat tappet for $1899.00 It's $565 dollars more than the Merlin iron heads, but flow will be better than the Merlins, weight loss is huge- approx. 30lbs per head, and the fact if something lets go aluminum heads can be repaired. Kinda sucks when the price gets up there, but you cant beat a great set of heads for any combo and aluminum has soo many more advantages over iron it warrants the added cost IMO.

You could also try looking at some racing boards for guys selling their stuff. You can't imagine the great deals out there if you look long enough with guy upgrading, getting out of racing, new combo, etc...Often you can get complete motors with some nice parts at waay les than it'd cost to build you own with the same components. Guess it boils down to budget like always
Old 11-16-2004 | 05:04 PM
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Ya those where the heads I was looking at. Even the afr heads i was looking at where raised alittle. What after-market head is out there that dont have the raised exhaust port, that will bolt on with no problem.
Old 11-16-2004 | 05:48 PM
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From: Waterloo, Iowa
Car: 86 firebird with 98 firebird interi
Engine: pump gas 427sbc Dart Lil M 13.5:1
Transmission: Oldani TH400 w/ BTE 9" convertor
Axle/Gears: 31 spline Moser/full spool/4.11Rich
I believe AFR's are 3/4" higher, Jegs brand aluminum heads are 5/8" higher, and I'm not real sure about Edelbrocks BBC heads. Maybe check out their site for some info if any or shoot them a quick e-mail.

upto 3/4" might be doable with some massaging, but I think 1" is quite a bit
Old 11-16-2004 | 06:53 PM
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From: The "D"
Car: A Portly 85 Z28
Engine: 4.530 X 4.250 BBC
Transmission: under rated for this application
Axle/Gears: also under rated
Raised port heads will cause headaches if you use the hooker swap headers. Any head that requires a special bolt kit will have a raised exhaust port. They raise the bolt boss up so the exhaust port can be opened up to flow better...I have heard the 049 heads are good but aren`t they closed chamber heads?
Old 11-16-2004 | 07:37 PM
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From: Waterloo, Iowa
Car: 86 firebird with 98 firebird interi
Engine: pump gas 427sbc Dart Lil M 13.5:1
Transmission: Oldani TH400 w/ BTE 9" convertor
Axle/Gears: 31 spline Moser/full spool/4.11Rich
there's a ton of close chamber heads, have to refer to the Mortec link thegeneral threw up. LOL, you definately dont want to run close chamber heads if you dont have to, have to set your motor up specifically for them.
Old 11-16-2004 | 08:23 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
I'm using 702 castings: 260cc intakes, 98cc chambers, just 2.06/1.72" valves. They were also used on 427's with 2.19/1.88 valves. Highly under-rated. Although open chamber heads are typically considered the better flowers, you have to use more domed pistons to get the compression up. With closed, you can get by with smaller domes. Either way, you have to build the lower end knowing what the heads are going to be.

Polishing the chambers helps reduce detonation - a common problem with early production heads.

With proper porting, valves & springs, stock heads will handle your proposed cam just fine. The aftermarkets would be nice, but not a very good HP/$'s investment.
Old 11-16-2004 | 08:32 PM
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From: The "D"
Car: A Portly 85 Z28
Engine: 4.530 X 4.250 BBC
Transmission: under rated for this application
Axle/Gears: also under rated
Nice link GENERAL! (mortec) looks like 049 are open with huge chambers..so much for hearsay
Old 11-16-2004 | 10:00 PM
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From: Pueblo Co
Car: 1989 C4
Engine: L98
Transmission: 700r4
Axle/Gears: 307
Last set of heads I used for the 402 that was slated for the truck were 290's with 2.25's & 1.94's. That engine got transplanted into my friends 72 nova, it needed a wheelie bar after the swap even broke 2, 9in setups.
Old 11-17-2004 | 11:22 AM
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I was looking around and I seen the edelbrocks are in the stock location, but they cost so darn much. I guess I will just look for some stock heads or maybe look on ebay, and then have them ported and cleaned.

Right know the 427 has arias dome top closed chamber pistons. so i will need the open chamber heads or i will have way to much compression
Old 11-17-2004 | 03:28 PM
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
What compression ratio are the pistons supposed to produce with closed chamber heads?

Unless that value is way too much compression, using open chamber heads would produce too low compression.
Old 11-17-2004 | 03:34 PM
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they produce 10.8 with 124cc cambers- 118cc is 11.5- and 108cc is 12.8
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