Hughes big mouth heads

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You can also do something like this.

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345man2 said:
I’ve been keeping up with this guy and he seems to know his stuff I may see if I can contact him, do you know of anyone else that has worked on this heads
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Just remember it an Edelbrock Mopar head with the same basic port as any speedmaster, ProMaxx, sidewinder, or any other Edelbrock copy. So lots of guys are familiar with the problem you are fighting. Now do some research to find out who can fix it and at what cost.
 
Belzona Super Metal will hold up to the ethanol blended fuels, it’s just way more expensive than typical epoxy.

I don’t have any reason in particular to think this is the case, but I’d be surprised if someone like Speier would even take on a job like reworking previously cnc ported heads.
But I guess a phone call would answer that question easy enough.
 
replicaracer43 said:
It will cost you more to correct those heads than they are worth in my opinion.
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I would put it more like this…….
If you took the money you would pay someone like Speier to revamp them, to the point they were actually “better” enough to justify the effort/expense of doing it, and added that money to whatever you could sell them for……..you’d have enough(or very close to it) to buy new heads.

Edit- I guess it might come down to whether or not he’s got any interest in working on heads like this.
On his site he claims he will evaluate someone’s heads, and offer a plan for improvements……..for free.
You just pay the freight.
 
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I had the engine dynoed with the stage 3 and when I put it back together ran on the same dyno with the big mouths , I know those numbers aren’t popular but same guy and dyno for both runs
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Let’s see those dyno sheets!
 
I’ve looked for some flow numbers for these after they have been hand worked and fixed but no luck , does anyone have any
 
The below is the reported flow numbers by Hughesengines.
Be aware of the flow bench they use which can be found at there site. Not all flow benches flow the same. They should be a tool used to show before and after work is done and not matched against another type or kind of flow bench including the same exact bench using the same program to calculate the air flow. Even the same flow bench will show different numbers on today’s hot and humid day and tomorrow’s cool and crisp day with humidity & spheric pressures differences.

The numbers on the far right of each on each column for the intake and exhaust are the Big Mouths numbers. They are labeled as such, “Big Mouth.”

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I’m going to correct you on one thing from this statement

Even the same flow bench will show different numbers on today’s hot and humid day and tomorrow’s cool and crisp day with humidity & spheric pressures differences.


An orfice style of bench is not affected by the weather like a pilot style bench. Maybe one or two CFM max. If you zero out a manometer style bench at 8am and check it at 12pm the manometer will have moved. There is even a chart that is to be used to insert the weather conditions at every lift number. This is why I got rid of that style of bench.
 
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What's the engine spec ?
Can you show the dyno results ?

You sure these heads don't need a different combination to make work ?
Ask Hughes why they think it slowed down ?
They should know what it takes to make these heads work.
 
had a buddy with a 9 second yellow Demon. W9 stuff. R3 block. If I remember he told me his peak flow was 370 ish....
Also said it was around 700 HP. Back half car, Alterkation front. It was a beast!
 
Ironmike said:
Call me crazy, but I don't see a 319 CFM head making 750 HP. Maybe on their dyno:thumbsup:
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Crazy? No.
It’s a bit of a stretch but if the engine size and combo are conducive with a high rpm ability of all the parts on/in it, I’d guess there would be a few people out there that could make it happen. I don’t see many motor heads achieving this alone.

The thing is, the rough rule of thumb is 2hp per 1cfm of head flow which has us at 638hp. Making up the power adds up to 375cfm head for 750 hp. The missing 112hp is a lot!

What does it take to exceed the 2hp per cfm?
A lot more than I know! Certainly a lot better build than I normally have.
 
rumblefish360 said:
Crazy? No.
It’s a bit of a stretch but if the engine size and combo are conducive with a high rpm ability of all the parts on/in it, I’d guess there would be a few people out there that could make it happen. I don’t see many motor heads achieving this alone.

The thing is, the rough rule of thumb is 2hp per 1cfm of head flow which has us at 638hp. Making up the power adds up to 375cfm head for 750 hp. The missing 112hp is a lot!

What does it take to exceed the 2hp per cfm?
A lot more than I know! Certainly a lot better build than I normally have.
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Just for example my buddy’s engine (408) made 638 horsepower with a set of heads I did for him. I was really restricted on chamber size so I wasn’t really happy with my flow numbers maxing out at. [email protected]. With my ported Super Victor intake it knocked that number down to 302. Matt ran [email protected] at 6400 rpm in some terrible weather conditions. One conversion chart I used said at 3200 pounds it made around 596 and the other chart said 611 so with some half decent weather it should be close. Slightly over .650 lift cam. You know me and horsepower numbers but I was bored.
 
I seen Darin Morgan say 2.5 hp per cfm is maximum, don't know how true that is or what it takes to get there, seen 3 engines do around the 2.35 hp per cfm.

In this video Chad says a 424 cfm head was good for 1025 hp on the dyno which is 2.41 hp per cfm.

As for the Big Mouths like to see a few engine making 750 hp and what it takes to do so if possible,
But don't think it's necessary impossible.

 
I think if it was possible(reliably), you wouldn't see guys using exotic W5 W9 stuff to get there. I mean, once you invest in a race block why even bother with anything done by Hughes.
Not a cheap shot, but a shot none the less. I fell prey to them. Once.
 
pittsburghracer said:
Just for example my buddy’s engine (408) made 638 horsepower with a set of heads I did for him. I was really restricted on chamber size so I wasn’t really happy with my flow numbers maxing out at. [email protected]. With my ported Super Victor intake it knocked that number down to 302. Matt ran [email protected] at 6400 rpm in some terrible weather conditions. One conversion chart I used said at 3200 pounds it made around 596 and the other chart said 611 so with some half decent weather it should be close. Slightly over .650 lift cam. You know me and horsepower numbers but I was bored.
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I’m no wizard at the HP guessing games myself.
We just get how stuff is put together and works.
Ironmike said:
I think if it was possible(reliably), you wouldn't see guys using exotic W5 W9 stuff to get there. I mean, once you invest in a race block why even bother with anything done by Hughes.
Not a cheap shot, but a shot none the less. I fell prey to them. Once.
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FWIW, do not consider a W5 as an exotic part. They are like an aluminum W2 w/rectangle ports. It has the same attachment to the block as a standard head and slightly wider intake holes which are easily modified to fit a standard intake. The rocker arms use stands are the only departure from a stock system. MP/Crane used to have a bolt on rocker arm set up.

If you move to a TD/Jesel set up, mounting them gets a little weird. TD wants you to move the bolt hole attachment point by redrilling the head. That’s where it’ll suck a bit. I would want to find an aluminum stud to cut to length and lock tight in before redrilling.

The W-7-8-9 are the exotic heads. There a good bit removed from stock.
 
If you look at the big mouth minimum cross section 2.57" should be good for peak hp at 6900 rpm with a 408, for a 408 to make 750 hp at 6900 rpms is 571 lbs-ft @ 6900 rpm which should be about 634 lbs-ft peak torque, 1.55 lbs-ft per cid.

1.55 lbs-ft ain't impossible but far from what most can achieve, I highly doubt that they built an actual 750 hp engine from them. In Hughes write up on them they call them 700 hp heads still need about 1.45 lbs-ft engine to get there which is still fairly high but more reasonable.

Eric measured a 2.78" minimum cross section don't know if he didn't subtract the corners, but his cross section say 7500 rpm peak which would be more doable but his flow look even worse for the big mouths chances for 700-750 hp.
 
There is more to a cylinder head being able to make power than the raw total flow rate. Those big mouth heads are a sales gimmick, in my opinion.
 
I’ve been telling you guys for years that the pinch isn’t the problem on an Edelbrock style of head. I’m at 334 cfm on a stock location pushrod head so far. Now can you make a better port horsepower wise moving the pushrod??? I’m betting yes.
 
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