Thread: 781 vs 049 heads

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I have a 1991 marine 454 in my 26' boat. I am looking to do some performance mods as indicated in my other posts. If I change to some beter OEM type heads, which would be better heads to go with? Or is there a better marine head I should go with.

I need low end torque, but still would like to rev to around 5500 rpms or so. Stock marine 454 has 330 hp, and I would like to bump that up. I eventually want to do a 496 stroker kit also, so these new heads would have to work with that as well. I would probably run a 850 Holley double pumper

Thanks.

Well Adam, if you're asking whether these (049 or 781) heads are good for what you want, the answer is yes....The 781's will be a little easier to find, but one is the same as the other, identical castings (for all practical purposes anyway) With bigger valves, (or even stock valves) and a little work, they will easily support a 5500 rpm engine, and if you go with the larger valves, will work nicely on your future 496. Those castings are considered my many to be one of GM's best 'as cast' production heads. John

o49 have a set. if you can not find any they are bone stock can be set up for roller cam and big valves i you are not building any thing bigger than a 454 then stock SS valves will be ok

Mr. McCarthy, always tryin to make a buck!!!

Originally Posted by 1JohnnyO

Mr. McCarthy, always tryin to make a buck!!!

well i am so sorry i can only work four hours a day with my health you try living on that kind of income

Okay, I thought they were pretty much the same castings, but weren't sure. Seems the 049's were going for more money for some reason. How much hp gain would I see on a stock 454 with 049 heads? Enough hp to make it worth it like 30 or 40 or?

Pat, sent you a PM I think.... asking about your 049's.

well i am so sorry i can only work four hours a day with my health you try living on that kind of income

Pat, Im only kidding!!! You know that, right??


Adam, the 049's were only made for one year, I believe...73 I think, so there are not so many of them out there, that drives the price up. Im not sure what you mean by the rest of your question...those WERE stock heads on a 454, as were the 781's...so any horsepower increases would have to come from installing larger valves, port work, etc. Pat would know better than I would, what kind of increases would come from that sort of work. I do know that they are very good heads to work with.

I have small peanut heads now, so going to a bigger head would allow more air flow correct? Even stock head design....

Are you positive you have the peanut port heads?? What's the casting numbers on them. Yes, a better head will flow more, but that larger flow is generally only needed at the higher rpms. The peanut port heads are actually not bad for low to mid rpm performance, lots of torque. I dont know that they would be good for extended runs at 5500 rpms however. Post the numbers for us.

I went to remove a valve cover and saw that I have to remove an exhaust manifold first. Uggg, it's never simple.

Holy cow!!! Sell the boat, buy a car!

Okay, I think the # is 14092360

Yep, you're right, that's the peanut ports. Well, if you go with the 049's or 781's, you'll be fine.

Okay, thanks. Now to find some cheap ones