906 TEMPLATE

Did Chrysler make any BB 906 porting templates? If so, anyone have access to them? Thanks

I have some xeroxed 1-1 on a sheet of paper. you can glue em to something stiff to use as templates. PM me your address & if I can find em I will send you a copy next week (pretty sure I know where they are at).

Dear Lord.
Wasn't that like, 1978?
Luckily, Mopar guys never throw anything away...somebody still has those little plastic cut-out templates laying around.

I still have two sets of the original plastic ones. Lol

I have some of the plastic ones 😁

Still got a set over my Dad's place, right next the Direction Connection Engine and Chassis manuals.

Here's a link to a PDF with some templates I came across awhile back. Figured I'd pass it along. -Trent

Mopar head porting templates

The only problem is....... They instruct you not to do what's required if you're really trying to see some nice gains.........which is rework the short turn.

I've lost count of the number of bowl blended, ported, big valve bowl blended, big valve ported 906/915 heads that I've had on the flow bench over the last 25 years that didnt break 240cfm......... All because the short turn was left untouched.

It's a double edged sword......... Don't rework the short turn......they don't flow much.
Rework the short turn incorrectly....... They don't flow much.

This is why for the novice or first time porter, the 346/902/452 head is a much better choice.
Ther basically is no short side radius to screw up.
Just blend away the sharp edge, along with the rest of the normal bowl blending..... And you have a decent head.

I could probably rough bowl blend a 346 head in less time than it would take to cut out the templates.

Come to think of if, I had someone send me some stage v heads with big valves that were done using the stage v specific templates...... Mid-240's iirc.

They're on the shelf, next to the .654 mushroom tappet cam.
You never know when you might need something like that, right (?)

"Tonight, on this episode of 'Hoarders':"

Fugget them old templates and go read these links to some original Tech Archives posts on porting factory iron heads.

http://www.moparts.org/Tech/Archive/bb/40.html

http://www.moparts.org/Tech/Archive/bb/42.html

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

http://www.moparts.org/Tech/Archive/bb/55.html

This is like Goldy Locks.......

A - First set - fresh valve job, OE type valve, bowl blended, no short turn work

B - Second set - dyno time only, valve job, Manley valve, bowl blended, short turn work done not as well as It should be

C - Third set - fresh valve job, Ferrea valve, bowl blended, pinch smoothed over, short turn done juuuust right.

All with 2.08 valve:

Lift-------A-----B-----C
.100---62.4/ 69.0/ 68.4
.200--118.3/148.8/138.4
.300--172.1/203.7/204.9
.400--224.9/238.1/251.3
.450--223.0/226.8/263.4
.500--224.9/228.7/260.8
.550--230.5/224.9/257.0
.600--232.4/224.9/251.3

I suppose 500" with a 590/600 lift cam and 915s that makes 645 hp 620 tq is like the seven dworfs?

Who in the heck would mess with those lousy 906 heads. Oh that's right, we did and had to 28 years ago. LOL. Those good for nothing super stock springs too.

Couple more for ya.....

Real nice 906 "F" head(not all F heads are great, but the best untouched 906's I've tested have been F heads), never touched previously.....
A- as removed from engine, oem valve and valve job

B- same port as above, grind 3 angle seat, back cut OE valve, minor bowl blend, no work to short turn

Lift------A/B
.100---63.0/68.4
.200--122.0/142.0
.300--179.3/201.3
.400--216.2/230.7
.450--223.0/234.4
.500--226.8/233.7
.550--232.4/230.0
.600--238.1/224.4

C- 915 head, old style MP 2.14 valve with back cut, bowl blend, basically no short turn work, and someone did a little opening/smoothing at the pushrod pinch;

Lift------C
.100---71.0
.200--145.1
.300--195.6
.400--229.4
.450--238.1
.500--238.8
.550--238.1
.600--237.0

A 915 someone sent in for tweaking......

A- what looked like a half hearted attempt at a bowl blend, OE valve, so-so valve job, no back cut

B- same port, remachine valve seat, bowl cut, blend bowl and short turn, Manley valve with back cut

Lift-------A/B
.100---61.2/69.0
.200--128.1/142.0
.300--187.8/206.1
.400--224.9/249.4
.450--225.6/260.8
.500--228.6/266.4
.550--232.4/268.3
.600--234.6/268.3

I still have a set of templates in one of my tool boxes. Hell I still have a set of 906 heads that are ported on the shelf.

Last one.....

A- "Ported" 906 head, SI brand 2.14 valve, no back cut, valve job done with a radius for bottom angle. Pinch opened to 1.070, guide boss trimmed a bit, some short turn work.
Didn't look too bad, and actually didnt work that bad in the upper mid-lift compared to a lot of what I see of these things.

B- open bowl more, relieve chamber adjacent to valve, longer top angle on valve job, a little more work on the guide boss, lay back the short turn, back cut valve...... Same cylinder as above

Lift-------A/B
.100---70.4/71.6
.200--124.4/156.6
.300--180.5/217.1
.400--229.4/255.1
.450--241.9/257.7
.500--243.8/258.9
.550--248.3/259.7
.600--248.3/258.9
.650--234.3/258.9
.700--234.3/259.7

The newer heads???
902 head(1974):
A- OE valve with back cut, grind 3 angle seat, less than 10 minute blend

B- open bowl a little more, bullet nose guide boss, pinch to 1.025", Manley valve with back cut

Lift--------A/B
.100---67.2/ 70.4
.200--139.0/142.0
.300--202.5/205.4
.400--230.5/244.5
.450--237.0/249.4
.500--240.7/254.0
.550--243.8/257.0
.600--245.7/253.2

I haven't figured out if it's stubborn or cheep, maybe I just wanted to prove the old junk can work.

Baaaaaahahahaha, I did until about a year ago! Found them in a drawer. Hey, back in the 80's, they helped me get my 440 smogger motor duster into the 11's.

Just keep having fun. That's what it's all about. When the fun stops, quit.

Waiting for confirmation, but Muscle Motors is supposed to have a CNC program for the 906 head. The bottom will still be $ vs reasonable results.

Uuuuuuummmm....... Isn't Muscle Motors closing the doors?

I can't imagine having a set of 906's CNC'd is going to be less $$$ in the long run than a set of E-street heads........ But I'm curious to hear what the number is.

I believe KG Engines also has a CNC program for 906's.

KG offers a standard port window CNC 906 and also a Max wedge port CNC 906.

Maybe someday a set of those will find their way into my shop for some reason or another...... And if they do....... A little trip to the flow bench will ensue.

I had a set that came from MM here a few years ago.
2.19" intake valve...... Worked pretty well.

I currently have a set of the standard port KG cnc 906s on my stock stroke 440. They work well I must say. 10.42@129 is my current best with traction issues. I have a set of the max wedge ones on the way and hope to have them on the car in a couple weeks. The rest of the engine besides the intake will remain the same. I am currently running a Victor intake and plan on trying a 337 M-1 and 440-2 with the MW heads. I'll post the results after they are installed and able to try both intakes.

I still have my set of 906 heads that went 9.80's with a stock 440 crank and rods and .030 over TRW pistons on a shelf. Maybe they will make a come back and be worth something. Lol

Did they happen to come with a flow sheet?

No flow sheet included.

Fast,
Good solid info as always. What pushed me to buy Edelbrocks was the fact that we lost 2 sets of 906s and a set of 915s to cracking, leaking after they had been heavily ported. We ran them for five or six years, then they were junk, and our investment was out the window. We've had that original set of Edelbrock RPMs since 2002, ran them on four different engines, two of which expired under them, and they are still going strong, so I can't see investing all that time and money into 40 year old castings anymore.

That's what happened to my good 906 heads that I still have but it was MY fault. Back then I always took a minimum .40 cut off the block and we would also cut the heads. I ran this set of heads MANY years and during a rebuild I didn't notice the dowl pins setting high and I cracked the head tightening it down when the dowl bottomed out. It started leaking at the Halloween Classic and I dumped a can of K&W block seal in it and ran them for 6 more races with zero issues but I haven't ever tried them since. I keep saying this but one of these days I would love to do a valve job and throw them on my flowbench. To this day I warn guys to set their heads on to make sure the head sits flush.

Billy..... I'm with you 100%.

I've thrown away countless ported iron bb mopar heads over the years, and some of them were very very nice heads, due to cracking.

Probably the nicest set I ever did myself went on a high level FAST build.
Motor made really good power, car went pretty fast.
It started using a little water pretty early on. The heads came off for some unrelated issue and got sent back to me for a look over.
There was a crack opened up right across the intake seat. No mag test needed for that one.
Had dyno time and maybe 20 passes on it.

The two main failure points seem to be, on the exterior under the center 2 ex ports, and in the chambers across the intake seats.

I'll tell you this...... Those high cr FAST strokers with short duration cams seemed to be extra tough on those heads.
I have a feeling that 260+lbs cranking pressure has something to do with it.

Wow, 30 posts and 700 views on home porting 50 year old crack prone scrap iron heads. Do we get another thread on when to use a 509 cam vs a 590 next?

I think now that mp has decided that the 509-108 cams are now worth their weight in gold, you may finally see them fall out of favor

They are expensive so they must be good, right?!

If you can get 906/452's CNC'd cheap as filler work to keep the 5-axis making money, I'd see them for street meat and cheater parts for cars that need to look stock.

To me, if I can just get the porting done for say $500'ish, I'd be game. I can do valve's, seats, guides, and blending, I just hate hunching over cast iron for hours.

It's not time sensitive, I'm not one of these A-holes screaming about needing their parts yesterday (because they're clowns who can't plan ahead after burning their junk up because they can't tune either.) S/F....Ken M

While I'm curious to know what KG or MM charges for the CNC part of the job, I'm not curious enough to call and find out...... Although I'd be shocked if it was something like $500.

The cheapest I can imagine it costing is like $800-900....... But I don't have a CNC machine to feed.

That being said, I thought someone told me they saw KG at a Mopar show with a display of bb and sb CNC heads for what sounded like pretty reasonable money.

$750 for aluminum head CNC is what I paid.

Unless your class requires it, I would trash the cast iron BB heads and use painted Stealths. The average person cannot tell the difference..

I think cnc'ing the iron is a little tougher on the cutters, and you probably can't cut as fast or as deep...... So it should just take longer.
I'm not certain of this...... Just how I imagine it is.

If that's correct...... It would seem like it "should" cost more to do the iron heads.

There are Dart SBC heads that are essentially the same, available in aluminum or iron.
I wonder if they cost the same to get CNC ported?

I know it's more difficult, I know there's more wear, although that isn't all that much with non-stupid feed rates. I also know that unless you have a backlog of business, $500 minus actual costs is more than 0 dollars. Very few machine shops have more business than they can handle. Most of the ones I know take a lot of time because they're run poorly ie disorganized.

Like so much, pricing is contingent on costs of doing business and what the market will bear. S/F....Ken M

When I talked with K&G over the Winter, they told me $1500 for a complete, ready to run set of 906's if I supplied the heads. That included the standard port window CNC program and new Ferrea 2.14 valves. I don't remember any more details about the work or anything else about the parts. He said that they flow in the low 280's; I want to say it was 283 or 4 (I don't know at what lift that number was recorded at). I've not seen a flow sheet. Very nice guys and I must say, it is tempting to me given the type of car I have.

I've spoken with a few people that have nothing but good things to say about K&G including one with a budget type 68 or 69 Road Runner that said their car picked up a second in the quarter going from basic rebuilt 906's to K&G's CNC'd 906's.

Parksr5 is correct. Dave will set them up with whatever spring you need. Mine look and perform great. I must say the only reason am running antique iron 906s on my ride is that the rules dictate that is what I must run. If I could run something else I definitely would. Seems like MM was in the $2500 range when I talked to Eric about them last year fwiw.

$1500 is cheap money for that job.

FWIW, I saw an article in a Mopar magazine about that 906 CNC service, had to be at least 4 years ago. Out of curiosity I called MM for pricing, they told me it was $2200, with customer cores.

Under optimum machining conditions aluminum removal rates would be much higher than cast iron, but the porting cutters and even the CNC porting machines capabilities can be factors in maximum cutting feed rates as much as the material being machined.

Three dimensional contouring of a port or something similar necessitates constant changes in directions. The ability of a CNC machine to process the code and the ability of the machines axis motors, software and hardware to accurately follow the programed tool paths often limit the highest practical feed rate, rather than the material being cut. The moving parts on the CNCs can only accelerate so fast in a short distance, and with the need to slow down for corners, then accelerate again, and slow down again feed rates are limited. So what is doable for actual feed rates for longer straight or gently curved paths is not obtainable for this type of machining. One way to visualize this is CNC tool paths are a lot like race tracks, short straight stretches with tight corners slow things down, even if the car could theoretically go faster.

On factory iron heads I doubt depth of cut is very deep over the majority of the port surface which would further speed things up and the feed rates probably can be run closer to aluminum than one might imagine.

Thanks for clearing that up Mike!!

Sounds like you're saying it probably doesn't take much, if any, more time to CNC an iron head over an aluminum head.

Wow I bet the customer could FEEL the difference on that swap!
That might pick up 1 second?
I used the templates on some 906s on my Super Bee. HMMMMM they might still be on that 440, 10:1 slightly bigger than stock cam (.468")? headers and six pack 12.18 with slicks 3780 #s with me in it.
Don

That's my best guess. I'm not not sure how many tons of metal we have cut with out CNCs, hundreds I would guess. I haven't done any full CNC head porting, but it's similar enough to other 3D surfacing like molds and stuff that I think my estimate is probably correct.

One think I know for certain is I hate machining cast iron, it makes a nasty mess, it's a lot like dirt or mud when you do a lot of it and the coolant washes it around in the machines. If you cut it dry then its like dusty dirt.