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View Full Version : What heads for mild BBC ???



bighead
05-03-2006, 02:12 PM
I am planning on upgrading the heads on my basically stock 1987 Hardin marine 454, the existing heads are the dreaded truck peanut port headWWW.Mortec.com :
14092360...86-90...oval...OPEN...454 Truck, "peanut" round ports. The intake is a Edelbrock air gap, carb isa 750 vac secondary Holley. Pump consists of a Berk E with a stuffer and inducer with a AT AA imp. The boat is a relatively heavy 21 foot open bow with through transom exhaust. What I am looking for is what is the casting # or head #to look for that would be best for this application. I know this boat is no speed demon but I would like to get a little more power and spin the pump more than 4,000 rpm. Any help will be greatly appreciated. Thanks, Bighead.

Daytona100
05-03-2006, 02:21 PM
049 and 781 are the good ones. 360 are the truck peanut port heads.

poncho-pwr
05-03-2006, 02:47 PM
There is nothing wrong with 049s on a motor like you are wanting. Have someone who knows what they are doing gasket match the intake ports and then have them work the exhaust ports to get them to flow better and you will see improvements and it shouldn't cost you too much. While your at it upgrade your camshaft, lifters and valve springs and maybe switch to an 800 or 850 double pumper and you would probably be happy. You could use your 750 vac secondary if you want to but I don't like vac secs on a boat. You already have an excellent intake manifold but the other thing you could do to wake it up a little more would be to add some through hull headers so it can breathe better.

BUSBY
05-03-2006, 02:50 PM
Rectangle Port 118cc heads (open chamber's):
6272990 or "990's"
14097088 or "088's"
3994026 or "026's"
good luck trying to find closed chambered heads
you have the 353049's (122cc, open chambered, oval port) heads?
if so ... find one of the three above mentioned sets ...
I have a set of 990's for sale, but are a bit big for you.

BUSBY
05-03-2006, 02:51 PM
good site for information:
http://www.mortec.com/bbc.htm

bighead
05-03-2006, 02:52 PM
WWW.Mortec.com :
14092360...86-90...oval...OPEN...454 Truck, "peanut" round ports

78Southwind
05-03-2006, 03:01 PM
What he said. The 049 heads are actually very good heads they just need to be machined for larger 2.19/1.88-inch intake and exhaust valves.
This article may be of interest to you it compares dyno numbers for two similar engines one using the 049 heads and the other using the 990 (188) heads.
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport.jpg
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport1.jpg
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport2.jpg
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport3.jpg
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport4.jpg
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport5.jpg
http://home.earthlink.net/~jrvalentine/sitebuildercontent/sitebuilderpictures/ovalportvsrectport6.jpg

SmokinLowriderSS
05-03-2006, 03:04 PM
Yes, the 353049's are a good Large Oval port head, a very solid base for a mild or a pretty wild 454. Their only "failing" is they have the stock small size valves (2.07/1.73).
I have been told by a local racing shop that they also respond amazingly to a basic Stage 1 porting job, to the tune of 75 to 80+ HP even with the small valves. Mine get ported next winter and the 2.19/1.88 valves too.
I have a much smaller and lighter 18', 1900 lb family ski/tube boat, but our setups are similar,
Moderate 454, getting wilder every year as budget allows
Berk F pump (E with factory trim)
Agressor "B" (equivilant to Berk "A" impeller)
Pro-loader from Hi-tech Perf.
Edelbrock Performer RPM Air Gap manifold
Holley 700CFM 4150 Mech Secc. carb.
You're gonna need a good bit of HP to spin that AA pretty hard, but it's not that hard to find. IMO you are well below the peak HP your engine is capable of making, but probably right at the top of the torque curve, your revs being held back by that big AA. If you can up the HP you have available, the RPM will climb, which will let you reach even more available HP at the higher RPM level. My stock 454 peaked the HP right at 4,000 RPM, but was spinning an A at 4850 due to the still very strong torque curve holding it.
If you are looking at buying heads, why not try to find a good, reputable shop to port yours and free up their breathing? My porting is looking like $1500 once I add Manley severe duty valves and new larger seats. Should net me close to 100 horses, with loads of torque too.
My stock Indmar 454 was running a sub-.500" lift cam straight from GM (.461/.480), the new Isky custom grind I got from Hi-Tech and ran last summer is working very well, .565" lift which should work with the ported heads very well.
My logs finally cracked & leaked internally, so got replaced with thru-transom headers this past winter, perhaps 40 or so more HP there this year.
I am trying to keep my power peak arround 5,000 RPM and it is holding well.

78Southwind
05-03-2006, 03:10 PM
Looks like you don't have the 049 heads. I would do a search in the spam section for heads. The last couple months I have seen a couple 049 heads for sale for about $400 and 990 heads for about $600 - $1500.

bighead
05-03-2006, 03:15 PM
I screwed up saying I had the 049 heads what I have are these, WWW.Mortec.com :
14092360...86-90...oval...OPEN...454 Truck, "peanut" round ports. As usual everyone is great at throwing info QUICK but I gave you the wrong info to start, sorry about that. Also the stock rating on the motor is 325.

slotracer
05-03-2006, 06:56 PM
got a set of stock 049 heads $300.00 plus shipping.
pat

poncho-pwr
05-03-2006, 08:14 PM
bEFORE YOU SPEND $1500 ON A SET OF 990s please save your money. Put a little more with that $1500 and get a set of aluminum heads complete. Now guys don't jump me, I'm not baggin on the 990s as I have seen them make big power when the right guy works them over.

lbzboyhb
05-03-2006, 08:17 PM
Are closed chamber ovals any good for a boat aplication 3931063
sorry to but in on post.

Fired Up
05-03-2006, 08:29 PM
I have a set of clean 049 heads with excellent Comp springs on them. PM me if you are interested. Run them as is or do the port/valve job they described above. I want them to go to someone who can use them.
Fired Up

Cas
05-03-2006, 09:17 PM
I have the 781's, had the 2.19/1.88 Manley Severe Duty valves put in along with the good guides, studs, seals, the whole shebang. The whole package was $880.00 and I really like the outcome. I would like to give you a comparison over the engine prior to the head change but there were also too many other changes to give an accurate assessment.
I also switched out the 360's with a set of 049's on a friend of mine's boat and he said there was a real big difference even though the 049's were totally stock with 39,000 miles on them after a valve job. As stated above, matching up the right cam, lifters, pushrods, springs, intake and carb can and will gain you a lot of ummph

SmokinLowriderSS
05-04-2006, 12:52 AM
Are closed chamber ovals any good for a boat aplication 3931063
sorry to but in on post.
IMO, they'd be better off in a car, but not a lot. They don't breathe as well as the open-chambered heads do at moderate and higher revs as the valves are shrouded by the casting. The open-chamber change was for emmissions reductions and had the by-product of unshrouding the valves and actually improved the flow and HP making of the engines. Turned out to be a win-win.

Bobbo541
05-04-2006, 07:04 AM
I have a set of closed chamber heads for sale that I took off my dragboat that are ported . I ran 7600 rpm and made @ 700hp on my 468 bbc. I ran these heads for 2 seasons .$1000.00 or obo.

396_WAYS_TO_SPIT
05-04-2006, 09:35 AM
Are closed chamber ovals any good for a boat aplication 3931063
sorry to but in on post.
Some people say no but my friend has them on his 454 and it runs in the 70's with a stock pump.
On the other hand, I have closed chambered rectangle port heads on my 461 and it hauls the mail. I had hung closed chambered pistons on my rods and didnt want to change. My heads are 108cc after the porting and milling...

HammerDown
05-04-2006, 09:52 AM
Worked over 049's doing a pretty good job on this 468 in my 21 Daytona.
But ya always want more...don't ya :rolleyes:
PS. kind of wish they were as light as Aluminum heads though.
http://www.***boat.com/image_center/data/500/1064ray-motor-halfsize.jpg

probablecause
05-04-2006, 11:46 AM
Family Jet boat OR Mild Jet Boat Engine = Looking for Higher Torque at a lower RPM. 049 or 781 are the way to go.

lbzboyhb
05-04-2006, 01:07 PM
thinks for the info..
new to the jet scene do hot rod car stuff mostly.
just got the boat 427 bbc 19ft 81 crusader berkley wb-b no diverter but hydro tabs took it out once crazy blow by pulled intake found a piece of a ring 1/2 long pulled heads found a piece of one piston missing about an 1nch long on the out side edge..
so motor rebuid and possible pump while i at it.thinking to much compression 11.25 i belive with cheap gas and poor maintenance by previous owner.
Surprisingly boat ran in the low 50s on gps this way thinking of switching to eldelbrock aluminum heads lower compression. Any thoughts on oval or square and how good thery work in a jet.

396_WAYS_TO_SPIT
05-04-2006, 01:13 PM
thinks for the info..
new to the jet scene do hot rod car stuff mostly.
just got the boat 427 bbc 19ft 81 crusader berkley wb-b no diverter but hydro tabs took it out once crazy blow by pulled intake found a piece of a ring 1/2 long pulled heads found a piece of one piston missing about an 1nch long on the out side edge..
so motor rebuid and possible pump while i at it.thinking to much compression 11.25 i belive with cheap gas and poor maintenance by previous owner.
Surprisingly boat ran in the low 50s on gps this way thinking of switching to eldelbrock aluminum heads lower compression. Any thoughts on oval or square and how good thery work in a jet.
I have a 12.5-1 motor and love it. I love the smell of avgas burnning too;) I have square port heads and the boat starts pulling really hard at 3800r's and up. Ovals are good up to 6000r's. What heads are you currently running?

lbzboyhb
05-04-2006, 02:44 PM
3931063 casting #