383 Build

mtnrat

Chief Petty Officer
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Jul 29, 2006
Messages
419
Re: 383 Build

I used the flywheel and flexplate from my 350 when I took everything in to get balanced.
 

StevNimrod

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Dec 13, 2008
Messages
343
Re: 383 Build

I used the flywheel and flexplate from my 350 when I took everything in to get balanced.

I've got a flywheel on the way (the old 350 is still installed in the boat) but what is the flexplate. When I pull up the diagram for the 350 that's installed (SN OF276159) all I see on the tail end is the flywheel and coupler. What is the flexplate?
 

Bondo

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71,079
Re: 383 Build

Ayuh,... Don't worry about his Flexplate,... You don't have 1, you've got the Coupler instead...

Your Machinest can balance Any flywheel to your motor,...
It just less drilling, or filling if you start with the 400 flywheel....
 

StevNimrod

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Messages
343
Re: 383 Build

Ayuh,... Don't worry about his Flexplate,... You don't have 1, you've got the Coupler instead...

Your Machinest can balance Any flywheel to your motor,...
It just less drilling, or filling if you start with the 400 flywheel....

Thanks Bondo! That's what I thought from pulling up the Merc diagram. I just wanted to confirm.

Last question of the day (hopefully) - I'm shopping for oil pumps and they appear to come in enough pressure/volume combinations to suit every situation. What are the pros/cons of using a high volume/std pressure pump versus a standard pressure and volume pump?

I think I read somewhere that a HV pump would suck the sump dry, but if I recall this was on a hotrod forum and I'm not sure how it works in boat engines.
 

Bondo

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Re: 383 Build

Ayuh,...

A Plain ole standard duty Mellings oil pump is All the oil pump you need....

Anything more is merely a talking point,....
And,..
Leads to added stresses on the distributer drive gear, for No Good Reason...

SBCs have Never been known for any lack of oiling issues,....
 

StevNimrod

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Messages
343
Re: 383 Build

Ayuh,...

A Plain ole standard duty Mellings oil pump is All the oil pump you need....

Anything more is merely a talking point,....
And,..
Leads to added stresses on the distributer drive gear, for No Good Reason...

SBCs have Never been known for any lack of oiling issues,....

Good deal. Thanks again Bondo.

I was able to magic up another question since my last post: I've currently got a 600 cfm Edelbrock 1409 carb, Chris (the custom cam guy) suggested moving up to a 750 cfm (like an Edelbrock 1410). Any another thoughts on this before I spring for another carb?
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: 383 Build

I'll have to find a PC I can use. One of the many joys of being a Mac user. I already have a custom grind en route, but I'd like to at least see what 3 phone calls and 2 hours on hold with Comp couldn't get me.

I don't care about sarcasm, keep it coming...if anything I tend dislike people who can't appreciate a little sarcasm.

If you don't want to soil yourself using Winblows you can put Wine on your Mac and probably run that Comp Cams program that way.....(I'd get it fast though....Comp just announced shutting down operations)

http://davidbaumgold.com/tutorials/wine-mac/


I'm going to try it on this Linux powered laptop I use for everything...


Cheers,


Rick
tuxxp.jpg
 

StevNimrod

Petty Officer 1st Class
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Dec 13, 2008
Messages
343
Re: 383 Build

If you don't want to soil yourself using Winblows you can put Wine on your Mac and probably run that Comp Cams program that way.....(I'd get it fast though....Comp just announced shutting down operations)

http://davidbaumgold.com/tutorials/wine-mac/


I'm going to try it on this Linux powered laptop I use for everything...


Cheers,


Rick
tuxxp.jpg

Thanks Rick! I'll definitely get Wine downloaded. The ship has already sailed on the cam, but I can still use it for a few other programs (most of the CAD programs out are Windows only).

When did Comp announce shutting down? I know Crane did, but I hadn't heard about Comp yet.
 

Bondo

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Re: 383 Build

I've currently got a 600 cfm Edelbrock 1409 carb, Chris (the custom cam guy) suggested moving up to a 750 cfm (like an Edelbrock 1410). Any another thoughts on this before I spring for another carb?

Ayuh,...

The Carb you've got is My favorite,... It's mathamatically plenty capable of feeding your motor....
Merc. doesn't go to the 750cfm til the BBCs,....
It's Your Cash,+ maybe Chris is right...

I'd run what ya got,+ See if you think you Need a 750....
 

StevNimrod

Petty Officer 1st Class
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Messages
343
Re: 383 Build

Ayuh,...

The Carb you've got is My favorite,... It's mathamatically plenty capable of feeding your motor....
Merc. doesn't go to the 750cfm til the BBCs,....
It's Your Cash,+ maybe Chris is right...

I'd run what ya got,+ See if you think you Need a 750....

I like the carb too and just rebuilt it last season. My math is showing that I'd have 50 cfm to spare with the current carb (assuming an unrealistic VE of 100%).

I think what Chris was speaking to was something about how strong of a signal the engine would be sending to the carb at idle. Maybe he can chime in to shine more light on that. Otherwise I'd be fine keeping my 1409.
 

HT32BSX115

Supreme Mariner
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Dec 8, 2005
Messages
10,083
Re: 383 Build

Thanks Rick! I'll definitely get Wine downloaded. The ship has already sailed on the cam, but I can still use it for a few other programs (most of the CAD programs out are Windows only).

When did Comp announce shutting down? I know Crane did, but I hadn't heard about Comp yet.


Gawd:eek: did I screw that up!!!! It was Crane!!! Not Comp..... and by the way I also read that they are probaby going to reorganize. That probably means they'll be back....
 

Tail_Gunner

Admiral
Joined
Jan 13, 2006
Messages
6,237
Re: 383 Build

Gawd:eek: did I screw that up!!!! It was Crane!!! Not Comp..... and by the way I also read that they are probaby going to reorganize. That probably means they'll be back....


:D...I for one can't tell how happy i am to hear you missed the mark. Christ i have 10 hours into comp cams cam grinds...
 

HT32BSX115

Supreme Mariner
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Dec 8, 2005
Messages
10,083
Re: 383 Build

I think it would be cool to put an aluminum 383 with aluminum manifolds/risers in my boat. I'll bet the whole mess would be at least 300 lbs lighter than the all iron 454 with iron manifolds and risers and could probably make as much power........
 

straubtech

Cadet
Joined
Mar 6, 2009
Messages
20
Re: 383 Build

The additional stroke adds greatly to piston speed in these engines. The draw on the 600 carb with stroker engines is greatly increased. Velocity is good but you don't want it to quick as the fuel will not mix with the air properly. Going to a 750 cfm carb ( CID x max rpm / 3456 = required CFM) is larger then needed but the draw on a 600 would be so great as you near the 4800-5000 rpm range that I feel it would give you a lean condition.
 

StevNimrod

Petty Officer 1st Class
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Messages
343
Re: 383 Build

The additional stroke adds greatly to piston speed in these engines. The draw on the 600 carb with stroker engines is greatly increased. Velocity is good but you don't want it to quick as the fuel will not mix with the air properly. Going to a 750 cfm carb ( CID x max rpm / 3456 = required CFM) is larger then needed but the draw on a 600 would be so great as you near the 4800-5000 rpm range that I feel it would give you a lean condition.

Thanks Chris. That's exactly what I was looking for. I remember you saying something on the phone about the potential for the fuel to not be atomized properly, but I wanted to make sure I understood the mechanics behind why. Running this thing lean, or even the risk of running it lean, could be a costly mistake.

Just heard from the engine builder that the pistons aren't going to be available until "the end of this month or the first of April". Joy.
 

straubtech

Cadet
Joined
Mar 6, 2009
Messages
20
Re: 383 Build

Thanks Chris. That's exactly what I was looking for. I remember you saying something on the phone about the potential for the fuel to not be atomized properly, but I wanted to make sure I understood the mechanics behind why. Running this thing lean, or even the risk of running it lean, could be a costly mistake.

Just heard from the engine builder that the pistons aren't going to be available until "the end of this month or the first of April". Joy.

What pistons are you looking for? Silvolite? FM?
 

Bondo

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Re: 383 Build

Thanks Chris. That's exactly what I was looking for. I remember you saying something on the phone about the potential for the fuel to not be atomized properly, but I wanted to make sure I understood the mechanics behind why. Running this thing lean, or even the risk of running it lean, could be a costly mistake.

Ayuh,... I ain't got a dog in this race,..
But,...
I'd throw some Skinny needles into the carb you've got now,+ Try to tune it to the motor after it's Runnin'...

Otherwise,...
You're throwing Away $300. for a problem that you Don't know actually Is a Problem...

There's a 'ell of a pile of 383s running Just Fine on 650cfm Carbs out there....
 

StevNimrod

Petty Officer 1st Class
Joined
Dec 13, 2008
Messages
343
Re: 383 Build

Ayuh,... I ain't got a dog in this race,..
But,...
I'd throw some Skinny needles into the carb you've got now,+ Try to tune it to the motor after it's Runnin'...

Otherwise,...
You're throwing Away $300. for a problem that you Don't know actually Is a Problem...

There's a 'ell of a pile of 383s running Just Fine on 650cfm Carbs out there....

I'll see your dog and raise you three horses, half the farm, and a few nights in the doghouse (read: sleeping on the couch). Which is about what I've got in this so far. Fortunately I'm down to about a month until I can put it in the water, so the timing should work out well.

I was able to get, for just over $100, a 1410 that was used one season and "the voice of reason" suggested that I get it, test both out, and sell whichever one I decide against. That way I can get some real data on both, compare the numbers, and post something that someone may be able to use in the future. After rebuilding the 1409 last summer (maybe not the best idea for my first carb rebuild), and swearing to all things I find sacred that I'd never do it again, it looks like I will be doing it again. Hopefully this time takes less than 4 hours.

That aside, does anyone have any pointers on the wiring for converting from a mechanical to electric fuel pump? I've got the wiring diagram, but would like to get it in terms a simple man can understand. Like, for example, where a good place is to tie into ground.
 
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