383 Build - Help!

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My 915 heads cc'ed at 80cc.
So long as you can get your CR somewhere in the 9s (true measured 9s that is)it's enough to get that snap that compression gives.
More is obviously nice but true 9s is adequate.
You can pick up a little more CR by using tin shim 20 thou head gaskets which is what I did.

Sooo....
383+40 20 thou below deck using 20thou tin shim gasket and allowing 5cc valve relief with 80cc 915s I get 9.47:1
 
I agree with nqkjw, in the 9's isn't bad, and good for pump gas. I'm just suggesting checking stuff first. It might not be .040" over, it might be .030" in the hole, and his heads might CC larger. Nobody knows for sure at this point. It will run OK regardless, it's just how well in the end.
 
CUUDAK said:
My Diamond pistons are stamped .060 on the bottom including the part#.
Click to expand...

Well, he may indeed be at .040" then. The last KB's I installed (2 weeks ago), were stamped on the top. They probably just had different methods at different times in production. Thanks for the info. I'd still measure.. ;)
 
BBBCUDA said:
I'd still measure.. ;)
Click to expand...
X2!
You still have the pan off I would pull one rod and check ring gaps which should be around .016 to .018. Go ahead and check the rod bearing clearances as well. It will only cost you a few bucks but in the end could save you several hundred. Since there are no heads on it I would also restrict the oil passages for the valvetrain. The passages run up the inside of the lifter valley near the rear of the block. Alot of oil pressure can be saved at the crank by doing this simple modification.
 
If the top ring gaps are .016-.018 there may be problems. That's how KBs got the bad rap that was all the builders' fault. That's why I said measure...
 
moper said:
If the top ring gaps are .016-.018 there may be problems. That's how KBs got the bad rap that was all the builders' fault. That's why I said measure...
Click to expand...

That is a normal ring gap for most ring sets. I know that the Hyperutectic pistons swell upon warmup. They are real noisey when cold. The only thing I can think of is ring "Butting". I did however fid this for ya,

http://www.kb-silvolite.com/article.php?action=read&A_id=32
 
CUUDAK said:
That is a normal ring gap for most ring sets. I know that the Hyperutectic pistons swell upon warmup. They are real noisey when cold. The only thing I can think of is ring "Butting". I did however fid this for ya,

http://www.kb-silvolite.com/article.php?action=read&A_id=32
Click to expand...


It's a gap you find in pregapped rings, yes. But, it's not what KB says to run...lol. If the rings butt, it doesnt get noisey. It looses power right up until the ring land fails and the piston breaks. Then it gets noisey.
Also, KBs (and hypers in general) do not change size when heated. If they are noisey, it was built with too loose a piston to wall clearance.
 
Schumachers are modified already. Some say I should have went with long tube, but from my point of view these fit well, are much better than manifolds, and I have a complete system.

Great info, I'll have to print all of this for reference.

How do I restrict the oil passeges?
And is that something I should do myself?

The crank is forged I believe, but it is not drilled for the 4 speed input shaft.
I know I can get a bearing for the 'automatic crank' and some people cut the input shaft.
I have no interest in cutting the input shaft.

How do I drill this?
What size and type of drill bit?
Does it have to be drilled absolutely perfect, or can I use a hand drill?

This is where I started with this engine, looking for someone to drill this.
I checked with every machine shop in the book, believe it or not, most I had to explain this to in detail, they had no idea. One knew, but did not want to do it, another could not fit me into their scheduled- what BS.

Hopefully I'll have time this weekend to put your advice to the test, and my own skills.
 
matthon said:
The crank is forged I believe, but it is not drilled for the 4 speed input shaft.
I know I can get a bearing for the 'automatic crank' and some people cut the input shaft.
I have no interest in cutting the input shaft.

How do I drill this?
What size and type of drill bit?
Does it have to be drilled absolutely perfect, or can I use a hand drill?

This is where I started with this engine, looking for someone to drill this.
I checked with every machine shop in the book, believe it or not, most I had to explain this to in detail, they had no idea. One knew, but did not want to do it, another could not fit me into their scheduled- what BS.
Click to expand...

Whoa there!!!
Back up a bit!!!
Don't know who you've been listening to but what you said above makes no sense.
All cranks are the same at the flange end.
If it was originally an automatic all you need to do is knock in a pilot bushing for the manual input shaft.
No cutting.No drilling.

All australian cranks are like this whether they be LA,slant6 or hemi6.
So unless the US did something different.
Someone please correct me if i'm off beam here.
 
nqkjw said:
Whoa there!!!
Back up a bit!!!
Don't know who you've been listening to but what you said above makes no sense.
All cranks are the same at the flange end.
If it was originally an automatic all you need to do is knock in a pilot bushing for the manual input shaft.
No cutting.No drilling.

All australian cranks are like this whether they be LA,slant6 or hemi6.
So unless the US did something different.
Someone please correct me if i'm off beam here.
Click to expand...

I agree, no need to drill the crank. Just pick up a pilot bearing. Most clutch kits come with the correct pilot bearing though. If you got a pic post it!
 
A cast crank may not be drilled. A forged crank may be drilled and finish reamed, or just drilled and not reamed. If the crank is not drilled any QUALITY machine shop should be able to do this and will know exactly what you need. You can't drill it by hand. It has to set up properly to get it perfectly centered and straight.
If it's not drilled at all, you will need to buy the bearing assembly that presses into the crank hub, but you'll also have to mock up the engine and transmission because you will need to cut the input shaft down a little so things fit. If it's not drilled at all, the input WILL contact the crank and the trans won't go all the way in.

On the oil passages - I would leave them alone.
 
My understanding is my crank was machined enough to accept the hub of the torque converter, (an automatic crank).
The 4 speed crank has a hole that is deeper, but not as wide.

A pic of my crank is below.
I have not had the current engine out yet, but I have seen '4 speed' cranks and they are definitely different.

The solutions are:
1) Have the crank drilled deep enough to accept the 4 speed shaft and crank bushing.
2) Use a special bushing, from brewers or mancini, and cut the shaft.
3) Use a special bushing, from brewers or mancini, and drill the crank deeper, (measure from the bottom of the crank hole to the bellhousing, and measure the input shaft to figure out how deep).

My understaning is, if you go with option 3, you can drill the hole a little wider to compensate for doing it by hand, and the larger bushing holds the input shaft centered and straight.

I have been unable to locate a good machine shop, so I am hopeful that option 3 is, well, actually an option. I understand the need to keep the input shaft centered and straight, and I do not want to cut it.

Mopar Muscle did this with an auto to 4 speed conversion, then with a 5 speed conversion the just used the bigger bushing, (I can only find the 5 speed article at the moment and the input shaft is not an issue, but they use the larger bushing).

Mopar Muscle
http://www.moparmusclemagazine.com/...ve_speed_transmission_conversion/viewall.html
Mancini
http://chucker54.stores.yahoo.net/pilotbearing.html
Brewers
http://www.brewersperformance.com/products.asp?cat=32
BigBlock Dart
http://www.bigblockdart.com/techpages/4sptech.shtml
 

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matthon said:
My understanding is my crank was machined enough to accept the hub of the torque converter, (an automatic crank).
The 4 speed crank has a hole that is deeper, but not as wide.

A pic of my crank is below.
I have not had the current engine out yet, but I have seen '4 speed' cranks and they are definitely different.

The solutions are:
1) Have the crank drilled deep enough to accept the 4 speed shaft and crank bushing.
2) Use a special bushing, from brewers or mancini, and cut the shaft.
3) Use a special bushing, from brewers or mancini, and drill the crank deeper, (measure from the bottom of the crank hole to the bellhousing, and measure the input shaft to figure out how deep).

My understaning is, if you go with option 3, you can drill the hole a little wider to compensate for doing it by hand, and the larger bushing holds the input shaft centered and straight.

I have been unable to locate a good machine shop, so I am hopeful that option 3 is, well, actually an option. I understand the need to keep the input shaft centered and straight, and I do not want to cut it.

Mopar Muscle did this with an auto to 4 speed conversion, then with a 5 speed conversion the just used the bigger bushing, (I can only find the 5 speed article at the moment and the input shaft is not an issue, but they use the larger bushing).

Mopar Muscle
http://www.moparmusclemagazine.com/...ve_speed_transmission_conversion/viewall.html
Mancini
http://chucker54.stores.yahoo.net/pilotbearing.html
Brewers
http://www.brewersperformance.com/products.asp?cat=32
BigBlock Dart
http://www.bigblockdart.com/techpages/4sptech.shtml
Click to expand...

Mine looked just like that! I knocked a bushing in that was included with the Ram clutch and it worked fine. No other drilling required. I just used a large bolt and nut with a flat washer and a deadblow hammer. DONE!

As far as the Oil Passage! Your choice! I preferred to keep the oil pressure on the crank. It is a simple modification that just restricts the volume to the valvetrain!
 
matthon said:
My understanding is my crank was machined enough to accept the hub of the torque converter, (an automatic crank).
The 4 speed crank has a hole that is deeper, but not as wide.

A pic of my crank is below.
I have not had the current engine out yet, but I have seen '4 speed' cranks and they are definitely different.

The solutions are:
1) Have the crank drilled deep enough to accept the 4 speed shaft and crank bushing.
2) Use a special bushing, from brewers or mancini, and cut the shaft.
3) Use a special bushing, from brewers or mancini, and drill the crank deeper, (measure from the bottom of the crank hole to the bellhousing, and measure the input shaft to figure out how deep).

My understaning is, if you go with option 3, you can drill the hole a little wider to compensate for doing it by hand, and the larger bushing holds the input shaft centered and straight.

I have been unable to locate a good machine shop, so I am hopeful that option 3 is, well, actually an option. I understand the need to keep the input shaft centered and straight, and I do not want to cut it.

Mopar Muscle did this with an auto to 4 speed conversion, then with a 5 speed conversion the just used the bigger bushing, (I can only find the 5 speed article at the moment and the input shaft is not an issue, but they use the larger bushing).

Mopar Muscle
http://www.moparmusclemagazine.com/...ve_speed_transmission_conversion/viewall.html
Mancini
http://chucker54.stores.yahoo.net/pilotbearing.html
Brewers
http://www.brewersperformance.com/products.asp?cat=32
BigBlock Dart
http://www.bigblockdart.com/techpages/4sptech.shtml
Click to expand...

That hole may or may not be reamed to size , the only way to find out is to try to put a pilot bushing in there, if it fits you are all set, if you mangle it it's not finished reamed. If this is the case use the one that fits in the converter register and trim a little off the end of the input shaft .
 
JohnRR said:
That hole may or may not be reamed to size , the only way to find out is to try to put a pilot bushing in there, if it fits you are all set, if you mangle it it's not finished reamed. If this is the case use the one that fits in the converter register and trim a little off the end of the input shaft .
Click to expand...

AHA !!!
NOW I understand the problem and what you blokes do to solve it!!!:cheers:
 
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