Moparts

How much HP potential from 516 heads?

Posted By: HotRodDave

How much HP potential from 516 heads? - 12/12/10 11:05 PM

I have a 440 and am considering what to do with it, I am a SB guy at heart and in practice. I know the 516 heads are not the best but just how much are you guys makeing useing them, either ported or untouched? I have my own valve grinder and the guides and stuff are fine so it would not be cost worthy for me to look for anything else.
Posted By: AndyF

Re: How much HP potential from 516 heads? - 12/12/10 11:09 PM

They'll work just fine for your tow truck.
Posted By: all spooled up

Re: How much HP potential from 516 heads? - 12/12/10 11:33 PM

NONE
Posted By: Bob_Coomer

Re: How much HP potential from 516 heads? - 12/13/10 12:48 AM

So this is a 516 Big Block head? The heads are key, but what is the rest of the engine?
Big diff in well ported 1.73 exh and 2.14 intake heads vs stock takes off's from a 67 383 with 1.6 exh valves.
Id say a moderate effort 400-450 hp should be rather easy with pump gas.
Posted By: HotRodDave

Re: How much HP potential from 516 heads? - 12/13/10 01:22 AM

Thanks Bob for the usefull answer.

400-450? Are they that bad? A SB can do that pretty easy with stock heads

The motor will be a 1967 HP short block with the deck milled to get zero deck piston height. For cam I was thinking something in the RPM and idle quality range of the comp XE268. Something like an eddy RPM intake. I can do some decent porting with some good instruction.

For a car I am looking for a short bed short cab dakota, aspen, volare mabey a 4dr dart or valiant.
Posted By: firefighter3931

Re: How much HP potential from 516 heads? - 12/13/10 01:30 AM

Some excellent info from Engine Guru Fast68 :

http://www.moparts.org/Tech/Archive/bb/62.html
Posted By: dennismopar73

Re: How much HP potential from 516 heads? - 12/13/10 02:28 AM

well the good is mm closed chambered
mmm they will work on youre big block
mmm they look really good cleaned and painted
bad anything after the paint

dont flow ,, bad seats prone to cracking worse than 906s
take more money to make them anything
just get set 452s or even better set of eddies
or buy set of 440 so stuff
Posted By: Quicktree

Re: How much HP potential from 516 heads? - 12/13/10 02:30 AM

for what it's worth many years ago I ran 906,915,516 heads on the same 440 in my RR. car ran the exact same thing with all 3 different heads
Posted By: ademon

Re: How much HP potential from 516 heads? - 12/13/10 02:46 AM

They should support 400 + hp fine, if looking for more than 450hp look for a 915 or aftermarket head
Posted By: dennismopar73

Re: How much HP potential from 516 heads? - 12/13/10 02:53 AM

what ya race with is diffrent than you drive
on the street harden seats vs non hardened
i to have run em too,, but, wouldnt waste my time ,for a street motor , 452 way better set, not prone to crack as 516 /906 and that maybe 1/2 point of compresion means almost nothin
for money spent to even make em good
if they are the only head , if the car was a restoration peice, had then i would

i do agree all heads being the same
you re car prob did run the same
so that proves that point / or 1/2 point of comp didnt help those 516 over come their realy bad flow either
Posted By: Dean_Kuzluzski

Re: How much HP potential from 516 heads? - 12/13/10 03:26 AM

Not sure if I'm qualified to post in this forum, but.............

my 69 383 Rr ran 13.08 at 105, thru the muffs, pistons in the hole .070, with MP template ported, 2.08/1.74 valved 516's.

I'm sure them old "doorstops" were holding it back.

I always enjoy it when this topic comes up........

Posted By: Maximus_Wedges

Re: How much HP potential from 516 heads? - 12/13/10 03:58 AM

Dave I ran 516 heads last summer on a 426. I did put in the 1.74 exhaust valve and bowl cleanup. Was able to get 11.90 in a light car. I was just "killin time" till my new motor was ready. If there ready to run and all the budget will alow run em till you can get something better. If you have to spend any thing much at all on them I'd jump right to an Alum. head.
Posted By: HotRodDave

Re: How much HP potential from 516 heads? - 12/13/10 04:31 AM

The deal is guys that I have thease heads, I do not have 915 452.... so I want to know how much potential thease have and what I can do at home to improve them, since I have a valve grinder and they need nothing but a quick VJ to run, probably would actually run fine as is but there is some very fine pitting on the seats. The guy was running them in a firewood hauling truck for years on 87 octane and the seats are not sinking, hardened seats are over rated on a mopar.

11.90 is good to me, no cage required and no $1000 set of heads.
Posted By: goldmember

Re: How much HP potential from 516 heads? - 12/13/10 04:35 AM

If 11.90's would make you happy then run them or a mild 360 with stock heads. Lot's of choices.
Posted By: tubtar

Re: How much HP potential from 516 heads? - 12/13/10 05:26 AM

http://www.youtube.com/watch?v=HUBiQTvTF68&feature=related

The answer you seek is at the 38 second mark of this vid.
Will Darnell knew a thing or two about cars.
Posted By: moparmafia

Re: How much HP potential from 516 heads? - 12/13/10 05:43 PM

we have a set of 516's that flow 276 and went 5.90 in the 1/8 in a 68 charger @3500 lbs. with the help of nos of course. so you could say they work ok i guess.
Posted By: dannysbee

Re: How much HP potential from 516 heads? - 12/13/10 06:42 PM

There was a Challenger from Texas that used to run in one of the NMCA classes in the 90's. Iron oem heads were required. I met the guy that ported the heads on that car. He claimed with a ported head he liked the 516 better as there was more meat to shape the ports to his liking. The Challenger ran at the top of its class. Had a wierd looking hood scoop on it. I will try to find some information.
Posted By: Mr.Yuck

Re: How much HP potential from 516 heads? - 12/13/10 07:17 PM

before I snapped a valve my old 516's w/ 2.14/1.81 valves flowed around 270/180. I'm guessing the car would have been in the 11's easy.
Posted By: HotRodDave

Re: How much HP potential from 516 heads? - 12/14/10 02:56 AM

At 270 CFM that would be enough for aproximately 540 hp correct? That would definately be more than enough. Any one know how much they flow with no port work?
Posted By: Cab_Burge

Re: How much HP potential from 516 heads? - 12/14/10 03:03 AM

Quote:

At 270 CFM that would be enough for aproximately 540 hp correct? That would definately be more than enough. Any one know how much they flow with no port work?


210 to 220 at .500 lift with stock valves and no port work, according to Don Little a long time ago
Posted By: forphorty

Re: How much HP potential from 516 heads? - 12/14/10 05:54 AM

Quote:

At 270 CFM that would be enough for aproximately 540 hp correct? That would definately be more than enough. Any one know how much they flow with no port work?


Flow numbers in the link that Firefighter posted above, from the archive: http://www.moparts.org/Tech/Archive/bb/62.html
Posted By: mbogina

Re: How much HP potential from 516 heads? - 12/14/10 02:25 PM

with way too much work, we have had 516 heads flow in the mid 280's/190's with the 2.08/1.60 valve sizes. In general, the port flow is terrible in stock form vs the 906/452, the castings are thin in the intake ports, the short side on the exhaust is non-existent, the exhaust ports are thin on the "hump" area on the side of the port walls. After lots of work, yes, we made 580+ HP on a 383/carter carb, ran a best of 10.35 at 3470 lbs, then they cracked through the exhaust ports. In general, too much effort for the results.
Posted By: HotRodDave

Re: How much HP potential from 516 heads? - 12/14/10 07:35 PM

So is 250 cfm something an average porter could get with stock intake valve?
© 2024 Moparts Forums