Just received the 8MM valves this afternoon. Here are the initial results, 1.92"/1.625" MP stainless valves, straight 45*, these are a set of Dodge Truck Magnum iron heads:

LIFT----AS CAST
---------IN/EX
.100"--67.3/N/A
.200"--131.3/97.3
.300"--185.6/132.5
.400"--212.5/144.9
.450"--213.9/146.3
.500"--212.2/146.3
.550"--212.5/146.3
.600"--213.9/146.6
.650"--214.2/147.3
.700"--215.3/147.3

Did some whittling on them:

















LIFT------IN/EX
.100"--67.3/N/A
.200"--132.8/115.6
.300"--196.0/156.6
.400"--225.0/172.2
.450"--238.1/174.3
.500"--250.5/176.6
.550"--257.1/178.0
.600"--259.1/180.8
.650"--259.1/180.8
.700"--259.8/180.8

The intake port has'nt had the chamber deshrouded on the sides, so the low lift will only get better. Overall I'm happy with it for a 1.92" valve and that God awful rocker boss taking up 1/2 the intake runner.

The exhaust I'm not happy with at all. It's either in the short turn, or just the still small runner/exit, So first order of business is to open it up a little more and see where that get's me. I will not quit until I see over 200 cfm.

I'm interested to see where this one goes. Have you done a set of 308's yet? Just curious to see a side by side comparison.
Tom

Cool! I've been wanting to know this info for a loooooonng time. Looks like MP is underrating them just a touch. They claim 190 cfm @ 0.550 (intake) for the plain ole untouched Mag head.

can't wait to see the final outcome! Just wish you would have started with the Magnum R/T heads!

Never done a 308. So Who wants to be the guinea pig on those? LOL That is how I ended up with these Magnums, mentioned I had never done one yet and had wanted to for quite some time just to see what they can do... and here they are LOL.

THIS post needs to go to the Tech. archives......

I did almost the same work on the heads that I installed on my stroker,but with 1.970's,and was wondering if/what they would flow(no bench)I like what you did with the exhaust port!! Was considering a set of R/T's for later on down the road,but maybe NOT!!!

Thanks for the update, Ryan. How do these flow numbers stack up against other Mopar 2.02 iron heads? I know it's apples and oranges, given the difference in valve size, but I would be interested to know the comparison.

great info...I'm bummed by the stock exhaust flow, and even ported, the exhaust flow doesn't look that much better than an older head (no fault of yours, of course)

one more question: what are the port volumes? how do they compare with the port volumes of an older 360 head (J/596/et al), eddies, and 302's? pre and post porting?

if the port volume is close to the 302's you did, geez, box stock these would rock on a 318.

Looks good to me.

Intake to exhaust is ok, I wouldn't beat yourself up over it.

I can see where you can whittle a bit more in the exhaust

Great flow numbers in my opinion, I know who I'll be sending my castings to if my 318 ever dies. These heads do work really well on 318's. I did the swap and would recommend it over 302 heads any day.

Oh yeah, no doubt I left some flow on the table so to speak on the exhaust port, this was only the first port I have done LOL. So I stayed conservative, just looking at it though I would have GUESSED it would have done better than 180 but....... I'll put it back on the stands and do some more "whittling" and find more air. I just wanted to get some initial #'s out there, because I have had ALOT of guys Email and PM me wanting to know what the magnums are going to do LOL. So hopefully this will supress their appetite for a while until I can get the heads done and post the final results LOL.

OH and Patrick, I'll try to CC a runner today if I find time.

Appetite suppressed for now....

Do you have any of your other as cast numbers available for comparison's sake? 302, J, X, W2, W5, etc.? There's probably alot of guys that will not do ANY porting and want to know if they are worth the conversion $.

That being said...

MORE, MORE, WE WANT MORE!

Oops I think I found some of them:

302's
LIFT----I-------E
0.100--55.2----34.5
0.200--105.2---70.7
0.300--152.0---104.2
0.400--187.0---113.2
0.450--189.8---115.5
0.500--190.1---117.3
0.550--190.4---119.0
0.600--190.4---120.4

596's
LIFT----I-------E
.100--62.8----48.3
.200--117.3---98.3
.300--174.2---120.8
.400--193.2---125.6
.450--192.5---127.7
.500--192.5---128.3
.550--192.5---129.0

looks good so far!!
which casting number are you working with?
reportedly, some of the variations are bigger than the others.
as for the exhaust flow.....180 is plenty for about 550hp on a typical SB application.

Casting #'s that I saw were a 5300 and a 6671 cast on the top of the # 1 and 3 intake runners. Looks like a 1995 Casting.

nice, I have a nice 318 we can try them on .

318!

OK, after looking at the initial numbers, I was pretty impressed. However, I went back and dug through the archives and found all the "ported" and "as cast" flow numbers I could, and those Magnums stack up very well. I was very impressed when I saw the ported 915 #s:
Lift Int/Exh
.100 61.9/58.4
.200 134.3/115.2
.300 190.2/141.4
.400 233.4/157.8
.500 258.9/172.3
.550 267.9/175.5
.600 273.9/181.9

Comparing the Magnums to these, the Magnums were very close, and the Magnum R/T's with the 2.02 valves should theoretically outflow the 915's. Now THAT would be pretty impressive.

I'm using the R/Ts for my daily driver below with my simple bowl cleanup. I did spend twice as long on the exhaust as the intake but did almost nothing on the intake valve guide like I see you've done. The numbers I saw (Car Craft) showed a major improvement on the exhaust side of the r/t vs magnum (168 vs 138 @0.50).

All your numbers are higher out of the box than what car craft got though.

I also widened the pushrod pinch by 0.08 and got rid of all the bosses? (lumps caused by neighboring threads).

I don't need the full on port you specialize in but i'd love to know what mine flow.

65Dart: those flow #'s are'nt off of my flowbench so, comparing them directly to these magnums is kind of tough. Here are some #'s off my bench if you wnat to compare:

From left to right: Magnum, Full port 2.02 "587" J head that has ran 11's, Edelbrocks I did for Coke Bottle Kid, and a set of Large port Commando's I just did.

LIFT--MAGNUM---"587"----EBROCK----COMMANDO
.100"--67.3-----62.1-----65.6------69
.200"--132.8----135.2----135.2-----140.1
.300"--196.0----198.7----197.7-----202.5
.400"--225.0----239.8----233.2-----246.4
.450"--238.1----253.9----245.0-----266.0
.500"--250.5----258.4----255.3-----277.1
.550"--257.1----264.9----265.7-----281.2
.600"--259.1----254.6----274.6-----282.9
.650"--259.1----N/A------279.1-----283.0
.700"--259.8----N/A------283.9-----285.3

In all fairness to the Magnum, all 3 other heads have 2.02 valves..... and the "587" J heads are the best low/mid flowing J heads I have ever done, so that is kind of misleading. They just ended up being a REALLY good set of heads. And you can see why IMO the Large Port Commandos are such a great head for the $.

For a more "fair" comparison, here is "Valcuda"'s "596" J heads with full port work and 1.88 Tulip valve next to the magnum:

LIFT--MAGNUM---"596"
.100"--67.3---58.7
.200"--132.8--120.1
.300"--196.0--182.9
.400"--225.0--225.6
.450"--238.1--238.1
.500"--250.5--241.5
.550"--257.1--247.0
.600"--259.1--248.8


And I'm not even going to bother listing race heads as that is comparing apples to oranges. I'll just say, a W-5 has absolutely KILLED every other race head other than a W-8 that has been on my bench.

I understand there is going to be some variance between benches, Ryan, I was just trying to make a ballpark comparison.

So, that being said, and with those numbers above, what would you say the best cast iron ported head below a W-2 would be for the money?

Cast Iron? Who wants cast iron? LOL Umm..............2.02" in a magnum, got to be best iron for the $ IMO. They have alot of advantages over old J heads etc. Better chamber, better wet flow, better exhaust (maybe LOL), lighter valves, round lock grooves, 10 valve cover bolts, just alot better catsings, hardened seats etc etc etc. Magnums are "the deal" IMO. Stuff an AMC pushrod oil lifter in it, hollow pushrods and run 'em.

Not quite like having them on your bench, but here is a link to some pictures of the R/T and Magnum heads side by side.

http://www.geocities.com/alwest_83/magnum.html

Jeff

I need to stick my fingers in an R/T intake port..... I could tell you within 10 seconds how much better they would be. Pics are OK, but you can't tell everything from a photo.

Any idea what the increase in flow would be using then MP porting templates?. I was also planning on going to the 2.02 intake.

How long did it take you to port the set you took the pics of?. Thanks .

I'll probably have 20 hours total in these heads. 1.5 Hrs per intake port and 1 hour per exhaust.

No idea about the porting templates....

More tidbits for the smallblock stew brewing here. My dad runs the Mopar Performance iron heads that were discontinued awile back. He bought them bare and had them ported and fitted with Manley chevy valves with the smaller stem.
Intake 28" h2o 1.96 valve:
.100= 74.7
.200= 140.9
.300= 193.5
.400= 224.2
.500= 242.0
.600= 242.2
Exhaust 1.60 valve
.100=53.1
.200= 107.1
.300= 147.2
.400= 167.0
.500= 177.6
.600= 182.3
I'll try to dig up a part number but I believe they were the old "swirl port" head. He has just bought some w-2's for next years project. "As is", they didn't flow any better than the heads he's running now (same bench).

I ported a set of magnum heads about 3 years ago and spent about 50 hours doing it!!! cast iron dust everywhere!!! next time( if there is a next time) I will use a mask as I started catching a buzzz after breathing all that dust .... My hand was also numb for about 2 weeks after all the grinding with my dremel grinder... but I was pretty happy with the end result as all I did was clean up the bowls but they really needed lots of grinding as the valve guide bosses have so much extra meat around them.... I used these heads on a 360 and they ran very well.. I currently have them on a 70 318 with headers and this thing has so much more power it's unbelievable.... The tall, skinny ports give good velocity and these heads make a nice choice for a street/strip setup.. based on how well they work on my brothers 318, I would say these heads are a great choice for a 318 .... Eventually, These heads will make it to my 109K mile 5.2 Grand Cherokee and I just might throw a 4" crank at it as well TBF

hey ryan, just curious if you'd cc'd a port yet, and how the port volume compares with some other "street" heads you've done

Really 183? Rumor had it that later-model 5.9's had larger 163cc ports (versus the 5.2L 153cc ports). The casting number you refer to is supposed to be the larger 5.9L head.

Did you measure before porting? Did you really take 20cc out of the bowl or did you go into the throat and runner to get that volume?

Jeff

Just got my heads. Wow. I like them so far.











Not the greatest pics in the work, but hey, they are better than none!

Look just like mine, real rough in the exhaust. With stock retainers/keepers I was way under the 1.64 spring height MP advertises, more like 1.595, but consistent. With hughes retainers (advertised plus 0.125, they were actually almost perfect at plus 0.045?) got me 1.64 for hughes springs spec'ed for 1.66.

I spent maybe 5 hours cleaning up and polishing the exhaust, definitely a lot a meat in the casting to machined area of the exhaust port, and around the valve guide.

The intake I only spent 3 hours (got the feel for the bit)as it was much "cleaner?" around the casting/machined area, but I did shave a good 0.080 off the pushrod pinch, and gasket match. Didn't spent much time at all around the valve guide, much more intimidating to me, hard to control the bit so I left it alone.

I also eliminated thread bulges where ever they could be found. This was my first porting (if you can call it porting).

Ryan very nice work keep up the good work and all the info you supply us on small block cyld heads your very helpful to a lot of people would like to see other shop post there numbers dont think your going to find anyone out there doing any better work then you thats for sure keep up the great work

From what I can see, I'm in LOVE with those Magnum R/T's.......

wow 183cc, that's bigger than I expected...is that about the same as a ported 360 or eddie? the 302's, werent those down near 145 or was is 163cc finished?

one more dumb question: chamber size-- how does it compare to the eddies and 302's?