Please Tell Me What You Think of This Build

[bobs66440]

Hello all,

Please tell me what you guys think of this combination and the est. hp.

440, .030 over, stock '69 Carter AFB & intake, ported 906 heads, 10:1 compression, high volume oil pump, windage tray, HP exhaust manifolds with TTI 3" down tubes. I'm looking for a good drivable street engine that has some snap when needed.

Cam:
int .465
exh .488
adv dur. .282
int. dur @ .050  .224
exh. dur @ .050  .234

Another option is the same combo with Offy low rise dual quad, two Eddy 500cfm.

Thanks!!

[Cooter]

I assume headers are out of the question?


Looks good. Are you running the "Six Pack" replacement pistons? If not and the tops look like the garage floor in the shop, then that compression might be a little off.

[MSRacing89]

Looks like you like it with a little old school feel, I can appreciate that!  If that is the case then improve on things you may not see.  Consider some roller rockers and take a look at the Lunati Voodoo cams #60303.  I wish you had you option in the for a Holley carb but you are the boss!  Not knowing what port work you have done, I will assume pocket port so 450hp.

[bobs66440]

Thanks for all the input guys! I really appreciate it as I'm not all that savvy with this stuff.

Anyway, here's the story as I know it.

The engine is as described. He built it to six-pack specs (hence, high volume pump and windage tray, which he said they came with). That's why everything on the motor is date coded '69 except the block as that was the original plan, but it ended up with the carb and intake as described because he ended up building a stroker instead.

It has Federal Mogul stock replacement flat top pistons.

He wanted the compression to be around 10:1 so the block was decked and the heads were milled and cc'd to stock closed chamber volume (can't remember the numbers but he estimates 9.8:1 actual)

Summit SUM-6401 cam.
Which states min. 9.5:1 compression.

The combustion chambers and exhaust bowls were polished to help avoid detonation. Intake ports were gasket matched.

He recommends 10-12* initial timing.

The thing is, I was able to pick it up for $1800. That sounded like a good deal, so I just couldn't leave it there. I figured it's worth the gamble. 

[Challenger340]

Thanks for all the input guys! I really appreciate it as I'm not all that savvy with this stuff.

Anyway, here's the story as I know it.

The engine is as described. He built it to six-pack specs (hence, high volume pump and windage tray, which he said they came with). That's why everything on the motor is date coded '69 except the block as that was the original plan, but it ended up with the carb and intake as described because he ended up building a stroker instead.

It has Federal Mogul stock replacement flat top pistons.

He wanted the compression to be around 10:1 so the block was decked and the heads were milled and cc'd to stock closed chamber volume (can't remember the numbers but he estimates 9.8:1 actual)

Summit SUM-6401 cam.
Which states min. 9.5:1 compression.

The combustion chambers and exhaust bowls were polished to help avoid detonation. Intake ports were gasket matched.

He recommends 10-12* initial timing.

The thing is, I was able to pick it up for $1800. That sounded like a good deal, so I just couldn't leave it there. I figured it's worth the gamble. 

NOT trying to rain on your parade, $1800 is a good price I guess...
but,
I HIGHLY DOUBT, that you having sufficient Block & Head Milling present, to be anywhere near 9.5:1 C.R., unless those Stock "non-Adjustable" Rocker Arms in the Pictures, have the Hydraulic Lifter plungers bottomed out ?

here's the Math;
The stock replacement Federal Mogul Pistons have a C.D. of 1.99" usually, I don't care WHAT the book says, most times when installed they will be sitting about .080"to .090" down in the hole....
Most 906 Heads with any rebuilding, which invariably sinks the Valve seats somewhat, will CC at about 87-88 CC's, lots closer to 90CC.
SO,
If this guy has MILLED the Block & Heads ENOUGH, that he "estimates" 9.8:1 ?
440 @ .030"over = 913 CC's Swept Volume
would require a Total "Clearance" Volume of 103.5 CC's to attain the 9.8:1 ?

To get to the above 103.5 CC's, if he was trying to get the 906 Heads down to the "Closed" Chamber spec of 79.5CC's, would require about .045" Head Milling(2.1CC per .010 Milling on a 906),
and
another .030" Milling off the Block, to get THOSE Pistons up around .060" from the top of the deck,
using,
a Composition Head gasket(10 CC's)

Either way, with THAT much total Block & Head Milling, the stock Intake would NOT fit, unless the Intake Face on the Heads was Milled to correct the Fit ?
and,
THOSE Stock Rockers would be Bottomed out....

For each .010" removed from the Block & Heads, about .012" should be milled from the Heads on the Intake faces, to correct Intake fit.
In this case, if he has done around .070" to .080" worth of Block & Head Milling to get anywhere near the 9.8:1, he would have needed at least the same 70/80 to get the Intake to bolt up.....
Does it look like the Heads have been milled, on the surface where the Intake bolts up ?
How "thin" is the surface on the Head, where the Valve cover gasket seals ?
From the pictures,
It does NOT look like THAT MUCH Milling has been done ?
Therefore,
I highly suspect it is probably more like 8 "something" to 1 Compression ?

Sorry, don't like being the bearer of bad news here.....



   

[BSB67]

I mentioned the same thing on his Moparts post before he bought it.  

To the OP: you should tear it down so you at least know what you have.  This way you can set your expectations on what it actually is.

[bobs66440]

Okay, thanks.


Here are some pics of the intake gasket. It's hard to tell what has been done by looking at it.

[bobs66440]

.

[bobs66440]

I was able to look inside the spark plug hole and get these numbers from the top top of the piston...

350P .030
222-00-17b

I know they are .030 over. I couldn't find any part number reference to Federal Mogul, but I found a Summit Z350P30 which seem to be the same though.

http://www.summitracing.com/parts/SLP-350P30/

As I said, I'm not real savvy with these things. So, what's the bottom line? Will it run like this or do I have to change something? Cam?

Thanks again!

[Challenger340]

* Pretty evident from the new photos, that the Block has NOT been milled much, if at all ?
If it had been Milled, there would be a "dimple", where the Intake crushes the Valley Pan down against the incorrect Angle at the corner, no dimple=no Milling.

Secondly, he has used a fiber Intake Gasket as well as the Tin Valley Pan, NO WAY he would get the Intake Bolts started if it were "Milled to 9.8:1", because, he's going the WRONG WAY !, He would need to LOWER the Intake Face to compensate for Milling !

* Those Pistons on Summit, are listed at an EVEN WORSE 1.94" Compression Height, than the 1.99" I was giving them earlier.....probably placing the Compression high 7's or low 8's to 1.

I know you are just wondering if it will run.....yes....ANYTHING will run....
but,
any comparisons power-wise to a 69/70 440-6 pack specifications, absolutely NOT !

What you have for comparison power-wise, is a smogger 1978 440, with a Cam added, maybe even less, if the last 4 digits on the Intake Manifold casting ends with 6178, which flowed even less than the '78 Intake.

Apologizes here, but THAT looks like what you have.

Best bet...
Pull a Head and verify the Pistons sit approx .120" down in the Cylinder at TDC ? if they are...THAT is NO "6-pack" spec anybody has ever heard of...and you have a High 7 to low 8 : 1 Compression Engine, basically a "terd" ?
* get your money back ?

[bobs66440]

Thanks for the info. I do appreciate it. You don't have to apologize... you are helping me  

Regarding the compression height., I double checked the Summit ad and it does list them as 1.99", not that it would make much difference. Am I looking at the wrong ad?

Ok, I will pull a head and measure it and let you know what it is.

Worst case scenario, I have this cam too. Do you think it will be better?

[ChargerST]

You could try to take a picture with an endoscope camera if you have one. Just unplug a spark plug and and see how deep the piston sits in the hole at TDC. Not very accurate but at least gives you an idea.

[Challenger340]

At this point, you have concerns with some "fundamentals" involved in this build. 
Paramount in these concerns, should be the suspected lack of Cylinder Pressure with which to work with, for ANY Camshaft contemplated....
Pull a Cylinder Head !
and,
either Verify, or conversely disprove, the suspected LOW Compression ratio, BEFORE moving ahead with any other decisions.

* You have nothing to lose at this point ?
If the Engine has not been run ? you can easily Bolt it back together.....Yes, you can even re-use the head Gasket.
However,
the options for any performance improvements moving forward, will be much clearer, including Camshaft selection.

[bobs66440]

Okay, thanks. I'll let you know what I come up with.  

Can I reuse the head bolts also? They are new and the engine has not been run yet.

[Challenger340]

Okay, thanks. I'll let you know what I come up with.  

Can I reuse the head bolts also? They are new and the engine has not been run yet.

Yes, the Head Bolts are re useable....
and if it has not been run.....the Head gaskets as well.

[bobs66440]

Ok, ya ready? Here's some pictures.

All the pistons were .085" in the hole except one that was .088"

It looked like all the lifters were bottomed out (see pic) if that means anything. When I removed the rocker shaft, they all came up.


It's a good thing I opened it up because this is what I found laying in there! Yikes!



Anyway, here are the rest...

[bobs66440]

.

[bobs66440]

Chrysler head gasket measured .015"

[BSB67]

Go through and clean up the short block and make sure everything is right.  The 1.99 piston and a .085 compression distance is not too bad of a place to start...the 1.94 would have been hopeless.  As it sits, it is less than 9.0:1 CR, unless the heads have been cut a lot,  which is unlikely as mentioned above by some.  The heads look like they are used, and possibly had a blown head gasket.

Get a set of Stealth heads, have them gone through, back cut the valves and put a good grind on them, and mill them to 75 ccs, add .020 gasket, and you'll have the potential for a decent runner.  you'll need a better cam too.

[firefighter3931]

With the pistons down .085 and assuming an 88cc chamber using a .020 steel shim head gasket your compression is right at 9:1 which is not terrible. I like to keep pump gas builds using iron heads at 9.5:1 max so you're not too far off. An 80cc chamber will get you there. 

If using aluminum heads you can up it one point and still be safe so that's an option as well.

For sure you will need a set of custom length pushrods to make this work...it appears that there is too much pre-load.



Ron

[68r/t]

I have the exact same pistons, I then milled my heads 55 thou to get them to 80cc and have a 9.4 compression ratio with felpro 40thou headgasket I have a crower hdp282 cam and I ordered a set of pushrods that were 50 shorter the standard from Smith Brothers to get the right preload on the lifter.

[bobs66440]

Go through and clean up the short block and make sure everything is right.  The 1.99 piston and a .085 compression distance is not too bad of a place to start...the 1.94 would have been hopeless.  As it sits, it is less than 9.0:1 CR, unless the heads have been cut a lot,  which is unlikely as mentioned above by some.  The heads look like they are used, and possibly had a blown head gasket.

Get a set of Stealth heads, have them gone through, back cut the valves and put a good grind on them, and mill them to 75 ccs, add .020 gasket, and you'll have the potential for a decent runner.  you'll need a better cam too.

Thanks for the info. Unfortunately, I don't have the cash for new heads. I will have to make these work. Will it run ok with this cam, or should I change it?

[bobs66440]

With the pistons down .085 and assuming an 88cc chamber using a .020 steel shim head gasket your compression is right at 9:1 which is not terrible. I like to keep pump gas builds using iron heads at 9.5:1 max so you're not too far off. An 80cc chamber will get you there. 

If using aluminum heads you can up it one point and still be safe so that's an option as well.

For sure you will need a set of custom length pushrods to make this work...it appears that there is too much pre-load.



Ron

Thanks!  How do I set the proper preload? The push rods are 9.31" (stock length). If the head wasn't milled, shouldn't the stock length push rods work? Or is the cam the issue?

Thanks,  Bob

[bobs66440]

Okay, I measured the current lifter preload on all the right side push rods and they all average .170" except one oddball was .100". That would be .110"-.150" too much preload! Yikes!

I have the left side head off, so I didn't measure that, but I would imagine it to be about the same.

As stated, they are 9.31" stock rods, so I assume the block/heads must have been milled? Am I wrong in assuming this? Could there be another cause?  

Also, I noticed that the exhaust valves sit about .070" higher than the intake valves. This may complicate finding final pushrod length?

[firefighter3931]

Okay, I measured the current lifter preload on all the right side push rods and they all average .170" except one oddball was .100

Assuming all measurements were done correctly on the base circle the only way for the variation is cam lobe wear/lifter problem or a different length pushrod. Something ain't right ! 

Definately too much preload and it needs to be corrected. This engine won't even fire because the valves would be held open with that much preload. 



Ron