Reply With Quote049 and 781 are the good ones. 360 are the truck peanut port heads.
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.
049 and 781 are the good ones. 360 are the truck peanut port heads.
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.
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.
good site for information:
http://www.mortec.com/bbc.htm
WWW.Mortec.com :
14092360...86-90...oval...OPEN...454 Truck, "peanut" round ports
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/~jrvalenti...vsrectport.jpg
http://home.earthlink.net/~jrvalenti...srectport1.jpg
http://home.earthlink.net/~jrvalenti...srectport2.jpg
http://home.earthlink.net/~jrvalenti...srectport3.jpg
http://home.earthlink.net/~jrvalenti...srectport4.jpg
http://home.earthlink.net/~jrvalenti...srectport5.jpg
http://home.earthlink.net/~jrvalenti...srectport6.jpg
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.
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.
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.
Posting Permissions