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Mr. Six Pack Engine Attack! Almost Pure Stock build...

Posted By: cudabin

Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/28/13 03:49 AM

I am starting the engine build for my numbers matching 440 six pack motor out of my 1970 Super Bee.

30 years ago, I did an old school rebuild using TRW six pack replacement pistons boring the engine out .030' and turned the crank .010"/.010". We did parrellel deck the block and set them up at zero deck, but nothing too fancy.

I bought a Mr. Six Pack cam this winter and decided to freshen the engine up in an "almost purestock" fashion using everything I have learned in the last 30 years.

Instead of boring the block out to .040" or .060" over, we simply honed it out with a torque plate until it was as round as we needed, then ordered custom Diamond pistons at .034" over. finished bore will be 4.354" with stock 3.75" stroke.

The TRW's with pin weighed 1,162 grams each, and the new Diamonds with a .145" wall tool steel pin weigh only 783 grams...
Saved 379 grams per piston and ended up with higher quality/stronger pieces!

I am using an .043" / .043" napier second / 3 mm Oil Ring package which should reduce friction and free up some HP.

Here are the Pistons with pin.

Cheers,

Arnie

Attached picture 7643791-Regina-20130327-00011.jpg
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/28/13 03:54 AM

Here is the underside which Diamond did a bit of lightening on for me...

Attached picture 7643797-Regina-20130327-00012.jpg
Posted By: sixpackgut

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/28/13 04:36 AM

so far you spent more on pistons and rings than the whole last rebuild. they look pretty
Posted By: gregsrt

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/28/13 06:11 AM

What shop did you use for machining here in Sask? Who do you recommend that is Mopar friendly?
Posted By: BSB67

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/28/13 11:31 AM

Really nice looking stuff. I think the lightest shelving pistons out there are the Icons and Ross and they come in at 820-840ish IIRC.

Are you going factory head? Will it be pump gas?
Posted By: scatpacktom

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/28/13 12:46 PM

No Pure Stock Drags for you?
Posted By: BSB67

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 12:16 AM

It is an occassional thought, it fades quickly. Same with FAST.
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 03:50 AM

The machining is being done by Bruce at ABS Competition Enterprise here in Regina.

Yes I am using the original 906 heads, but since they were already pocket ported, it would not be a real pure stock build. Also there is no venue for that here in Canada.

The original Six Pack Rods were magnafluxed/ crack checked and then we added ARP 2000 rod bolts and resized the bottom end.

The top end of the rod will be bushed for the floating tool steel pins, and we will adjust the piston deck height with the bushing placement to get each piston precisely at the same deck height. The block deck surface was still good and checked out to be right on for parrellel.

There are a few more tricks to be done, so I will update as we progress, then share the dyno numbers using factory exhaust manifolds.

cheers,

Arnie

Attached picture 7645160-Regina-20130502-00023.jpg
Posted By: 440forPOWER

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 06:30 PM

Thanks for posting. I'll be watching this post closely. I'm planning on rebuilding my 440 6 with Mr.Six Pack cam and specs. Thanks
Posted By: greenmcode

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 08:20 PM

What kind of compression you looking at?
Posted By: gregsrt

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 08:26 PM

'The machining is being done by Bruce at ABS Competition Enterprise here in Regina'

That's where I was going to take my 400 block to get machined. I've heard more good than bad about him. thanks
Posted By: rftroy

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 09:12 PM

I'll be doing a very similar build to my 70 Roadrunner six pack engine, which is now .030 over.

Were you able to get a custom size of ring to match the pistons? Going an extra .004 over will increase the ring gap by about .013".

Bob
Posted By: 79410aspenrt

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/29/13 10:07 PM

i have my small block at ABS competation in Regina. it should be done in a week or so.

Bruce must be good at machining and building engines. his shop is jammed packed with engines. the back part of the shop is engine after engine.

must be doing something right.

good guy to deal with, i've had no problems.
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/31/13 05:25 AM

Compression will be set at 9.5 to 1, so that i can run it on non - ethanol 91 octane. No quench and iron heads are stopping me from trying more, plus the Mr Six pack camshaft while being more aggressive on the ramps, does not have enough duration to bleed off the squeeze...

The rings came with the pistons from Diamond, but a "file to fit" set for .030" over should work and will just require less filing... I think this .034" overbore is worthwhile to leave more meat in the cylinder walls for better ring seal and cooling.

Yes I highly recommend Bruce at ABS if you want to make some good power in SK,

Cheers,

Arnie
Posted By: BSB67

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 03/31/13 01:57 PM

9.5 is probably about right. Double check your intake valve closing point. Despite the small duration, you might be surprised depending on your ICL.
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/01/13 05:24 PM

I plan to install the Mr. Six pack cam at 114 degrees ICL, which would be straight up.

The Super Bee has the Super track pack 4.10 gears, so this should favor the upper rpm slightly at 114.

Arnie
Posted By: gregsdart

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/01/13 09:07 PM

Those pistons and rings ought to help in the hp department a lot! Are you going to use stock valvetrain? Looking forward to the dyno sheets.
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/01/13 11:38 PM

Almost stock Greg...

It already had the 2.14/1.81 valves in it, with 1.5 ratio Crane ductile iron rockers. (Honest, those are stock 273 pieces...)

The old double Isky springs with retainers weighed 150 grams, and the new comp #26120 Beehives w/ #1795 tool steel retainers only weigh 104 grams for a savings of 46 grams. The benefit is actually greater as only the active part of the spring wieght counts and the heaviest part of the beehives is the bottom two coils which don't move.

This saving of wieght over top the valve should help the Johnson Hylift short travel hydraulic rockers work better at 6,000 rpm.

The chambers have been unshrouded ala Dan Dvorak's advice to me years ago, and the valves were back cut to improve lowlift flow.

So it is basically "Almost Stock" valvetrain...

More tricks planned, but always interested in learning new ones!

Arnie

Attached picture 7650638-Regina-20130422-00017.jpg
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/05/13 07:37 PM

In keeping with the Almost pure stock theme... I bought a Rev-n-nator ignition box from Rich at Firecore. All hype aside, if Dave Dudek is using one on his pure stock Bee and said it made 16hp more than the MP Chrome box at 6,000 rpm, I want to try it!

I will dyno first with the MSD system normally used on the dyno, then once tuned, i will compare the Rev-n-nator.

cheers,

Arnie

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Posted By: Dunnuck Racing

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/06/13 01:48 AM

Just keep in mind when you switch ignition boxes,you will most likely need to adjust your timing . Best power with each system on all the engines I have done the same test with usually likes a few degrees less with the Rev N Nator after switching.
Also when you first make the switch your timing will change some due to the way it picks up the reluctor signal.
Keith
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/06/13 04:59 AM

Thanks Kieth,

I understand about different boxes needing to redo the timing to get back to the same number, but i wonder why this box would want less total timing????

Iron head 906 w/ 9.5 to 1 compresssion at a 4,000 foot DA and 70 degree air temp usually likes 37 -38 total.

Why does the rev-n-nator want less?

Arnie
Posted By: Dunnuck Racing

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/06/13 02:44 PM

Arnie ,
I don't want to step on Troy's toes and give away any information that Im not supposed to,but it just has to do with the way the process the signal from the pickup coil.
I just wanted to make sure you knew. I know the first time Dave Dudeck tested with one he wasn't impressed because he was short on time on the dyno he was at and didn't take time to dial it in. It was later on when he had time to play with it that he got the improvement .
If I can help at all let me know. Or you can call Troy since its his baby.
Keith
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/06/13 04:02 PM

Here is the new Firecore HP coil that looks almost stock...


Cheers,

Arnie

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Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/08/13 12:28 AM

Ignition gets finished off with the old MP electronic distributor. It has a curve with 18 degrees mechanical advance, giving 20 intial and 38 degrees total. A new cap and rotor from Firecore, and of course a new set of Firecore 8mm 250 Factory fit Spark plug wires.

Looks mostly stock, but should light the fire...

Attached picture 7658459-IMG-20130405-00016.jpg
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 04/23/13 04:12 AM

Bought a couple of Quick Fuel jet kits for the outboards on the Six Pack.

Bob K suggested I start with #83 - #81 jets (staggered) and go from there...

Will start with #65's in center carb.

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Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/09/13 09:31 PM

Decided on a 10.5" Centerforce Dual Friction Clutch and throw out bearing, as some of the FAST guys have used them on the skinny bias tires, so they must be able to be slipped a bit... I will be sure to remove the assist spring under the dash to avoid issues shifting at high RPM's !

10.5" should have a little less rotating mass as well to help with traction on street tires.

Attached picture 7699578-Regina-20130423-00022.jpg
Posted By: Thumperdart

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/09/13 11:23 PM

Nice build...............good luck.
Posted By: 440forPOWER

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/10/13 12:41 AM

Just curious, why did you stay with the factory six pack rods? Did you have to for pure stock? Thanks
Posted By: JohnRR

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/10/13 01:02 AM

Quote:

Just curious, why did you stay with the factory six pack rods? Did you have to for pure stock? Thanks



All depends , if he gets the car certified then he would probably have to , though I think an H beam is as heavy as a 6pk rod .

Edit , just reread the thread , I see he switched to a lighter piston so he must not be getting certified because his piston choice is not legal.

It doesn't make any sense to reuse the 6pk rod with it's questionable bolt size to rod weight discrepancy , but the lighter piston helps with that problem.
Posted By: BSB67

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/10/13 01:30 AM

Quote:

Quote:

Just curious, why did you stay with the factory six pack rods? Did you have to for pure stock? Thanks



All depends , if he gets the car certified then he would probably have to , though I think an H beam is as heavy as a 6pk rod .

Edit , just reread the thread , I see he switched to a lighter piston so he must not be getting certified because his piston choice is not legal.

It doesn't make any sense to reuse the 6pk rod with it's questionable bolt size to rod weight discrepancy , but the lighter piston helps with that problem.



The rule prohibits lighter pistons?
Posted By: JohnRR

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/10/13 05:49 AM

Quote:

Quote:

Quote:

Just curious, why did you stay with the factory six pack rods? Did you have to for pure stock? Thanks



All depends , if he gets the car certified then he would probably have to , though I think an H beam is as heavy as a 6pk rod .

Edit , just reread the thread , I see he switched to a lighter piston so he must not be getting certified because his piston choice is not legal.

It doesn't make any sense to reuse the 6pk rod with it's questionable bolt size to rod weight discrepancy , but the lighter piston helps with that problem.



The rule prohibits lighter pistons?



Pretty sure that is the way it is, they were going with NHRA stock rules up until a year or so ago and NHRA stock does not allow the use of lightweight pistons nor having valve reliefs in pistons that were not originally installed like that by the factory ... not that people haven't used them .
Posted By: BSB67

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/10/13 10:42 AM

Quote:

Quote:

Quote:

Quote:

Just curious, why did you stay with the factory six pack rods? Did you have to for pure stock? Thanks



All depends , if he gets the car certified then he would probably have to , though I think an H beam is as heavy as a 6pk rod .

Edit , just reread the thread , I see he switched to a lighter piston so he must not be getting certified because his piston choice is not legal.

It doesn't make any sense to reuse the 6pk rod with it's questionable bolt size to rod weight discrepancy , but the lighter piston helps with that problem.



The rule prohibits lighter pistons?



Pretty sure that is the way it is, they were going with NHRA stock rules up until a year or so ago and NHRA stock does not allow the use of lightweight pistons nor having valve reliefs in pistons that were not originally installed like that by the factory ... not that people haven't used them .



Maybe I'm looking at the wrong rules. PSMCDR? They appear silent on piston weight, and frankly allow a lot of freedom on pistons.

"Engine: Must be factory correct for the year, model, and horsepower claimed. Dealer-installed engines and dealer-performed engine modifications are not allowed. Casting numbers must be correct for the year and horsepower claimed including intake manifold, heads, and exhaust manifolds. Head modifications are prohibited, including, but not limited to, porting, bowl cutting, gasket matching, oversized valves, etc. Heads can be cut to help achieve the allowed compression over advertised. Blocks do not have to be "numbers matching," but they must be the correct displacement. Overbores up to .070" are allowed. Stock cranks only. NO strokers! Random P&G checks are possible. Lightweight cranks and connecting rods are NOT allowed. If found, you will be banned from the event until corrected! Aluminum rods are NOT allowed. Smaller-than-stock rod journals are NOT allowed. Aftermarket pistons are allowed, but piston rings can be no thinner than 1/16", 1/16", and 3/16" for top, second, and oil rings, respectively. Gas porting of pistons NOT allowed. Metric and pressure-back-type rings (dykes, head land, etc.) are NOT allowed. Torque straps allowed.

Compression Ratio Limits:
All Engines – 1.5 extra points allowed over advertised. Contact us so we agree on the advertised compression.

a.Engines with factory dished pistons will be allowed to run either a smaller dish, a flat-top piston, or a small domed piston to achieve the maximum allowed compression.
b.Engines with factory flat-top pistons will be allowed to run a domed piston to achieve the maximum allowed compression.
c.Engines with factory domed pistons must run a dome of equal or greater dome volume than stock to achieve the maximum allowed compression ratio.
d.Heads can be milled and blocks decked within reasonable limits in combination with a), b), or c) above to help achieve the maximum allowed compression ratio."
Posted By: JohnRR

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/10/13 02:36 PM

That's the new rules that have gone away from NHRA specs , I guess what the OP is doing with a lighter piston is ok .

This is one of those gray areas that have lead to the current situation.

I was building my 383 to NHRA spec when I saw the pending rules change and called either Dan or Bob about it , that call lead me to change directions on my build.
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/11/13 09:37 PM

I have no need to "certify" , as there is no Pure stock racing in Western Canada, and i had already pocket ported the heads many years ago... This one is an "almost pure stock build" with stock bore/stroke, factory manifolds and exhaust system, street tires etc... But hopefully faster than when original.

The six pack rods will be just fine as the pistons/pins are very light and we put ARP 2000 bolts in, and the redline will be 6,000 rpm anyways. I won't lose any sleep at all worrying about them.

Cheers,

Arnie
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/13/13 09:06 PM

Just started on the crankshaft to remove casting flash and smooth out.

Next step will be to shape counterwieghts to reduce windage, and finally to cut the counterweights down as part of the final balance to match the lighter pistons, which will further reduce windage!

Attached picture 7704511-Regina-20130510-00026.jpg
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/27/13 03:36 PM

Ended up machining approx two hundreths off the counterweights as part of the finish balance after shaping the counterweights as below.

Attached picture 7720732-Regina-20130524-00033.jpg
Posted By: polyspheric

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/27/13 09:36 PM

Re: " The benefit is actually greater as only the active part of the spring wieght counts and the heaviest part of the beehives is the bottom two coils which don't move."

Actually, the bottom coils (the lowest "active" coils) move first. The beehive is progressive, with the rates differing by:
1. spring OD
2. spring pitch
The upper coils are stiffer for both reasons, and compress last.
Posted By: polyspheric

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/27/13 09:44 PM

You should radius and feather those eyebrow cuts into the dome.
Depending on your minimum volume, some reports of small improvement by connecting the cuts - but not always to full depth.
Posted By: Big Squeeze

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/28/13 02:30 AM

Quote:

Compression will be set at 9.5 to 1, so that i can run it on non - ethanol 91 octane. No quench and iron heads are stopping me from trying more, plus the Mr Six pack camshaft while being more aggressive on the ramps, does not have enough duration to bleed off the squeeze...

Cheers,

Arnie



It wouldn't surprise me at all if it still detonates....I built a VERY similar motor about 15 years ago and at 9.0 to 1 it would still detonate at 1/3 throttle taking off from a stop sign...IMHO quench isn't an option if you want to run over 8.5 to 1 compression...
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 05/28/13 05:03 AM

Quote:

You should radius and feather those eyebrow cuts into the dome.
Depending on your minimum volume, some reports of small improvement by connecting the cuts - but not always to full depth.



i understand the benefit to removeing sharp edges on the piston top, but to what exent does it improve power, and how much should the top edges of the valve reliefs be radiused??

Any pictures to guide??

Thanks for the input!

Arnie
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 06/05/13 09:16 PM

Redid the valve job and just a little more shaping in the bowl to improve mid lift flow. No sense in going for max flow as the Mr six Pack cam with true 1.5 rockers still does not exceed .500" lift...

Intake flow @28

.100 = 75.3
.200 = 150.6
.300 = 200.6
.400 = 229.6
.500 = 238.3
.600 = 240.4


how does that look to you 906 guys???

Cheers,

Arnie

Attached picture 7732088-Regina-20130524-00032.jpg
Posted By: JohnRR

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 06/05/13 09:30 PM

Quote:

Redid the valve job and just a little more shaping in the bowl to improve mid lift flow. No sense in going for max flow as the Mr six Pack cam with true 1.5 rockers still does not exceed .500" lift...

Intake flow @28

.100 = 75.3
.200 = 150.6
.300 = 200.6
.400 = 229.6
.500 = 238.3
.600 = 240.4


how does that look to you 906 guys???

Cheers,

Arnie



About the same as my "F" 906's with just a NHRA legal 3 angle ....
Posted By: cudabin

Re: Mr. Six Pack Engine Attack! Almost Pure Stock build... - 06/05/13 10:21 PM

Hey John, same .200 /.300/.400 numbers too ???

I did not ask my engine guy to go crazy on the heads, but i did request a midlift flow increase...

His flow bench and dyno are definitely not "happy" as his engines run the numbers at the track, but i am curious about the balance of flow at lower lifts and if i should have another go at it?

Then again i am choking this one off with the stock exhaust???

Arnie
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