Second thoughts on a cam choice.
Thread Starter
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
Originally Posted by Little Mouse
As long as you have a flex plate for a 400 small block they are external
balance if you are taking one off a 350 they are internal balance and
wont work. factory 400 cranks are external balanced at both the
balancer and flexplate/flywheel.
balance if you are taking one off a 350 they are internal balance and
wont work. factory 400 cranks are external balanced at both the
balancer and flexplate/flywheel.
Yeah, I was gonna grind the factory crank, re-use the flex plate, and use a new balancer.
Le Mans Master
Joined: Sep 2001
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From: Unreconstructed, South Carolina
Originally Posted by I'm Batman
Stupid 400 SBC question: I have a forged steel racing crank that is supposed to be set up for 5.7" rods. Do I still need to use 5.7" pistons, or should I use regular 400 pistons? 
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
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From: Columbia Missouri
So say I build this motor as I have panned thus far. Will the Hot Cam work well for my motor...which I plan for lower RPMs and lots of torque and cruising...?
Even with the shorter rod, will I suffer cyl bore problems if I don't abuse the motor and play int he highest of RPMs too often?
When I first designed this engine a few people, mostly Third Gen Camaro guys, all said this was a good build and I wouldn't have problems with it.
Even with the shorter rod, will I suffer cyl bore problems if I don't abuse the motor and play int he highest of RPMs too often?
When I first designed this engine a few people, mostly Third Gen Camaro guys, all said this was a good build and I wouldn't have problems with it.
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by Durango_boy
Okay, so reading this, all I need to do is buy some 5.7" rods, and the crank I have and the piston heads I have will work? Will this put the compression over 10.0:1, and will I have to get a different than stock head gasket?
Yes, I plan on having the crank ground down and get oversized bearings. I have never had an assembly balanced...how is this done?
Yes, I plan on having the crank ground down and get oversized bearings. I have never had an assembly balanced...how is this done?
Last edited by 63mako; Oct 8, 2006 at 09:03 PM.
Thread Starter
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
Originally Posted by 63mako
The crank will work. If you have 400 20 over pistons for a stock 400 rod 5.565 they will not work with a 5.7 rod. So you need new pistons and new rods. If you are buying new pistons and new rods anyway why not go with 6" rods and matching pistons? Or use what you got and don't push the motor.
I'm good at restraining myself or at least being carefull with my RPMs.
Le Mans Master
Joined: Oct 2001
Posts: 5,943
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From: Wildwood IL
Originally Posted by Durango_boy
I have never had an assembly balanced...how is this done?
My Wisco forged pistons & Eagle forged rods were within spec out of the box, but my Scatt crank had to be done over again when I switched from hyperutectic to forged pistons.
Good luck
Eddie
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Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by Little Mouse
How much will it cost for a machine shop to grind the crank
redo the rods with new rod bolts and rebalance. by the time you
do that the cost may be half what a new balanced 6.0 rod
assembly will cost.
redo the rods with new rod bolts and rebalance. by the time you
do that the cost may be half what a new balanced 6.0 rod
assembly will cost.
Last edited by 63mako; Oct 8, 2006 at 10:19 PM.
Thread Starter
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
Originally Posted by 63mako
That $1100 FORGED rotating assembly might look a little better when you add it all up. Saving a couple hundred now could cost a couple thousand later plus labor and inconveniance to remove and replace engine.
Well, you would think so except I have already bought EVERYTHING but the main and rod bearings and I have not had the crank ground yet. I have purchased EVERYTHING else, and I doubt it's worth a lot to anyone on Ebay. I think this motor will get built the way I had originally planned. Now, back to the cam qustion. Will a Hot Cam do me well. I know a better one exists, but will I suffer from things like fall-off idle and low vacuum?
That's all I really need, because I'm at the point in it's build where I need to change the cam now or hold my peace.
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From: Forked River NJ
Originally Posted by Durango_boy
Well, you would think so except I have already bought EVERYTHING but the main and rod bearings and I have not had the crank ground yet. I have purchased EVERYTHING else, and I doubt it's worth a lot to anyone on Ebay. I think this motor will get built the way I had originally planned. Now, back to the cam qustion. Will a Hot Cam do me well. I know a better one exists, but will I suffer from things like fall-off idle and low vacuum?
That's all I really need, because I'm at the point in it's build where I need to change the cam now or hold my peace.
That's all I really need, because I'm at the point in it's build where I need to change the cam now or hold my peace.
Thread Starter
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
Originally Posted by Gordonm
You should have a great idle with the hot cam. You are not running much duration for a 400 cube motor so your vacuum will be very good at idle. The hot cam will be real stump puller from idle to about 5000 rpm. Should do just what you want it for.
Perfect. Thanks Gord. That's exactly what I wanted to hear.
Le Mans Master
Joined: Sep 2001
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From: Unreconstructed, South Carolina
Imagine young Mr. Nimrod flies he & I in his light private aircraft to a Saturday AM show at a strip 200 miles from home. We've planned to begin return flight early-evening. We have good weather en route and a great get together. Lotsa coffee, BS & friendship. But as we're preparing to return ... the weather radio & (someone else's) radar indicates an ominous, slow-moving front has blanketed most of our return route with thunderstorms, hail & gale winds imbedded w/tornadoes. The other pilots (many more experienced than Mr. N) tell us we'd better not fly. When Mr. N replies that we're gonna fly and we'll probably be OK, most of the those same pilots tell us we're nuts but it was nice knowing us.
Do you think we should fly then? ... or ... go get a rental car and bear the added expense of retrieving aircraft later?
No doubt in my mind ... if Mr. N flies, he'll do it solo ... I've arranged a rental car. As Mr. N lifts off, I'm hoping he makes it home OK ... but my gut tells me I'll spend Monday evening at the visitation ... w/ the widow Nimrod.
The analogy differs mostly in that a hot street motor with crappy internals probably won't draw blood ... only $, time & lotsa face. That's my tale & I'm sittin' on it. G'Luck DB!
Do you think we should fly then? ... or ... go get a rental car and bear the added expense of retrieving aircraft later?
No doubt in my mind ... if Mr. N flies, he'll do it solo ... I've arranged a rental car. As Mr. N lifts off, I'm hoping he makes it home OK ... but my gut tells me I'll spend Monday evening at the visitation ... w/ the widow Nimrod.
The analogy differs mostly in that a hot street motor with crappy internals probably won't draw blood ... only $, time & lotsa face. That's my tale & I'm sittin' on it. G'Luck DB!
Race Director
Joined: May 2005
Posts: 10,674
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by Durango_boy
Well, you would think so except I have already bought EVERYTHING but the main and rod bearings and I have not had the crank ground yet. I have purchased EVERYTHING else, and I doubt it's worth a lot to anyone on Ebay. I think this motor will get built the way I had originally planned. Now, back to the cam qustion. Will a Hot Cam do me well. I know a better one exists, but will I suffer from things like fall-off idle and low vacuum?
That's all I really need, because I'm at the point in it's build where I need to change the cam now or hold my peace.
That's all I really need, because I'm at the point in it's build where I need to change the cam now or hold my peace.
Last edited by 63mako; Oct 9, 2006 at 08:37 PM.
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by jackson
Imagine young Mr. Nimrod flies he & I in his light private aircraft to a Saturday AM show at a strip 200 miles from home. We've planned to begin return flight early-evening. We have good weather en route and a great get together. Lotsa coffee, BS & friendship. But as we're preparing to return ... the weather radio & (someone else's) radar indicates an ominous, slow-moving front has blanketed most of our return route with thunderstorms, hail & gale winds imbedded w/tornadoes. The other pilots (many more experienced than Mr. N) tell us we'd better not fly. When Mr. N replies that we're gonna fly and we'll probably be OK, most of the those same pilots tell us we're nuts but it was nice knowing us.
Do you think we should fly then? ... or ... go get a rental car and bear the added expense of retrieving aircraft later?
No doubt in my mind ... if Mr. N flies, he'll do it solo ... I've arranged a rental car. As Mr. N lifts off, I'm hoping he makes it home OK ... but my gut tells me I'll spend Monday evening at the visitation ... w/ the widow Nimrod.
The analogy differs mostly in that a hot street motor with crappy internals probably won't draw blood ... only $, time & lotsa face. That's my tale & I'm sittin' on it. G'Luck DB!
Do you think we should fly then? ... or ... go get a rental car and bear the added expense of retrieving aircraft later?
No doubt in my mind ... if Mr. N flies, he'll do it solo ... I've arranged a rental car. As Mr. N lifts off, I'm hoping he makes it home OK ... but my gut tells me I'll spend Monday evening at the visitation ... w/ the widow Nimrod.
The analogy differs mostly in that a hot street motor with crappy internals probably won't draw blood ... only $, time & lotsa face. That's my tale & I'm sittin' on it. G'Luck DB!
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Don't say we didn't warn ya
Let me see now if I have this correct. 406ci with stock 5.565" rods and pistons, 350ci cam and 180cc heads ?
Let me see now if I have this correct. 406ci with stock 5.565" rods and pistons, 350ci cam and 180cc heads ?
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by MotorHead
Don't say we didn't warn ya
Let me see now if I have this correct. 406ci with stock 5.565" rods and pistons, 350ci cam and 180cc heads ?
Let me see now if I have this correct. 406ci with stock 5.565" rods and pistons, 350ci cam and 180cc heads ?
If anyone knows it would be you, that the key to a sucessful engine build is well matched components carb to pan!
Last edited by 63mako; Oct 9, 2006 at 09:07 PM.
Thread Starter
Team Owner
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From: Columbia Missouri
Originally Posted by 63mako
Ok. Take it your not reconditioning the rods ends, installing new pin bushings or balancing the assembly and still got to have the crank ground. Good luck on your flight home son. Cam should work great for as long as she stays together!
The new pistons came with new pins, and they are getting conditioned when the pistons are swapped.
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by Durango_boy
The new pistons came with new pins, and they are getting conditioned when the pistons are swapped.