SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: electrowoman on September 06, 2009, 03:16:57 PM
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Would someone with head porting experiance please let me know what you think of the picture.
I heard the Edelbrock heads make more HP if you don't remove the material from the bottom of the head port. Note the black area where the exhaust logs are larger than the head port.
This is in a boat, rpms run to 5200. Should I port match them over the winter or do you guys think that would be a mistake?
It's a 460 with long bolt logs
Thank you in advance.
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I'm going to say it even though it will be unpopular. :-[
Those heads are aluminum and that material is there for heat transfer reasons that I still have yet to understand...(I have only owned on set of beercan heads ever).
I would leave them alone...the reason I say that is the manifolds are bigger than the heads, that means there will probably be no gains to be had, besides the exit velocity of the exhaust gasses may be effected and you may actually lose on the big end...
I could be wrong, but I'd leave em.... :-\ Even though I would normally say hog em.
GT
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That's where I'm at GT. I have the same doubts and feelings :banghead:
Common sense says hog them. The little voice in my head says, wait a minute.....
I'm hoping some cylinder head experts are on here. With 5200 rpm on the top
end I just don't know what to do.
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if you dont know what you are doing (such as myself :-[) send them to a proffesional (sp?)
i would recomend charlie evans or scott johnson at reincarnation
http://www.evansracingengines.com/ (http://www.evansracingengines.com/)
i will find the other link in a bit.
should cost around a 1k or so to get them ported and flow tested.
the other link
http://reincarnation-automotive.com/ (http://reincarnation-automotive.com/)
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Leave them alone....not like they are AFR heads.
Imo you will not gain anything based on dyno results that I have ran .
Open for discussion or anyone elses exp. :-\
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Leave them alone....not like they are AFR heads.
Imo you will not gain anything based on dyno results that I have ran .
Open for discussion or anyone elses exp. :-\
i beg to differ, how is it not possible for a head that flows say 220 @600 to make more hp than a head that flows 190 @ 600 ??? with the appropriate mods to go with the extra flow?
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Consider the costs. to mod. the "Edel Heads"
Do the math...then dyno for results.
AFR or BRODIX my call Ralphy.... ::)
I do like edelbrock heads though for the coin.
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afr and brodix dont make heads for fords (as far as i know?)
i believe the edels will support in excess of 800hp if you want to spend the money.
but good point :thumbup: why do you want to port the heads ???
cheaper ways to get more power, (optimize your combo)
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Woooooow fellows. I'm not talking about a full blown port job. I'm talking about
port matching to my logs. Just trimming the black area in the picture on the heads.
I would never consider trying to race port them, they would go to a pro. I don't
have the exhaust to make that worth while at this point.
I'm just trying to optimize what I have.
What do you think?
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if gasket matching makes you feel better go ahead, i dont feel you will see any performance gains that are noticable. your jet pump will absorbe your efforts, and your tach wont show any more rpm
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Seems like I'll have to find something else to do. No sense messing it up
for no gain. Thank you all for your input.
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if gasket matching makes you feel better go ahead, i dont feel you will see any performance gains that are noticable. your jet pump will absorbe your efforts, and your tach wont show any more rpm
I agree with Ralph.... You stand to gain more investing somewhere else ::)
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Would someone with head porting experiance please let me know what you think of the picture.
I heard the Edelbrock heads make more HP if you don't remove the material from the bottom of the head port. Note the black area where the exhaust logs are larger than the head port.
This is in a boat, rpms run to 5200. Should I port match them over the winter or do you guys think that would be a mistake?
It's a 460 with long bolt logs
Thank you in advance.
As mentioned in the other Forum, lowering the exhaust port floor in these heads while used in your application will cost you power in your current combination.
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I'm talking about port matching to my logs. Just trimming the black area in the picture on the heads.
I'm just trying to optimize what I have.
What do you think?
No. Even the OEM iron heads, which already have the lower port floor, are rarely gasket matched at the port exit, and almost never is this done in a combo such as yours.
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i beg to differ, how is it not possible for a head that flows say 220 @600 to make more hp than a head that flows 190 @ 600 ??? with the appropriate mods to go with the extra flow?
It's not black and white, Ralph. While it may be possible for a certain cylinder head flowing 220@.600" to support/generate more horsepower than one that flows 190@.600, the opposite is also true. Exhaust flow numbers by themselves mean virtually nothing. So does flow ratio; unlike the beliefs of yesteryear we now know that a "good" flow ratio is unimportant and that flow ratio can be whatever it turns out to be, and that the combo can be built around intake/exhaust flow numbers as optimized.
It seems to me that so many enthusiasts are really hung up on flow numbers. ??? I don't know for sure why this is but I suspect that the reason is because cylinder head flow is expressed in numerical values which is a form of measurement that many people can identify with. "If the number is higher, it must be better" ::) Not always. Depends on the combo. We don't want flow to be as much as possible out of a cylinder head for a given engine combo, we want the flow to be just right for a given engine combo. Further, what is of paramount importance is the quality of flow. And in this particular case, the quality of flow in the Edelbrock heads will suffer for the given engine combo and application.
LO
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I do like edelbrock heads though for the coin.
Relative to the other after market offerings, Edelbrocks have come to be pretty damn low on the food chain of aluminum heads for the 460.
LO
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Relative to the other aftermaraketofferings, Edelbrocks have come to be pretty damn low on the food chain of aluminum heads for the 460.
LO
Gotta agree with you...once again...Ok. for the coin/ yet not my choice for heads :thumbdown:
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Those heads are aluminum and that material is there for heat transfer reasons that I still have yet to understand...(I have only owned on set of beercan heads ever).
Not there primarily for thermal transfer but this point is certainly noteworthy.
...the exit velocity of the exhaust gasses may be effected and you may actually lose on the big end...
That's the big reason! The velocity will be affected by way of the increased turbulence/tumbling of the exhaust gasses as they try to round that port floor whose turn has been made much more abrupt.
LO
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By the way, Electrowoman, so as not to steer you in the wrong direction: yes, if your heads are as-cast then they would indeed benefit from portwork, however, lowering the floor is the exhaust is not part of that modification in this particular case.
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Sooooo. can we all agree to leave the Edel. heads alone....and maybe just do a Stage I ??? ???
Or WHAT ??? ??? GEEZ ::)
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I'm kindof in agreement with Glenn on these aluminum heads anyways. Just now figuring Chebbies out, another matter, but on Fords, why bother when there are so many good flowing cast iron heads out there at much cheaper prices than the aluminum ones are anyways, unless you are racing? Kindof a solution that doesn't have a problem, IMO.
My thinking would be the dissimilar metals expanding and contracting differently to varying temps, and low temps, hot spots, etc we see on open water with the things would cause more problems than worth on a family boat designed to be worry free. We don't run our boats at WOT all the time (Yeah I know, I kinda do,actually more my son these days, but that is the exception, I'm an idiot trying to see how my first Jet Boat engine build will hold up, and it's amazing me!).
I would be willing to bet a set of D2's or C9's would probably be close or better than the Edelbrocks and they can be had easily for under $400 a set. Even the std C3's are fine to make a gob of HP.
On the street, well, maybe aluminum is the way to go on the 460. I would argue that one for other reasons, but that is not what this site is about.
On the other hand, want a balls out Hot Rod or racing boat? Well then be my guest! I just think it's going to be a headgasket blowing nightmare in very short order, and retorquing the heads after every trip would be mandatory.
Just my .02, and Paul , and others, will be quick to point out the flaws in my thinking on this.
Ray
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I have been told by a Ford freak freind (whom shall remain nameless) that these are the best bang for the buck hands down.
http://www.fordracingpartsdirect.com/product_p/m-6049-scja.htm
He has built some of the baddest marathon motors I have ever witnessed. :thumbup:
GT
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Thank you all for your input! The heads will stay as they are.
Now you opened up another question....see next post