4.3 bellhousing for 16" flywheel

Technorunner

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Does any one know if the boltpattern for the bellhousing against engine changed when they changed to 1 pcs seal and the new crankshaft??

the reason i wounder is that i have an 4.3 chevy 1995 that im converting to marin and i have a 16" flywheel to it but the bellhousing i got my hands on are for a 14" flywheel. So if the bolt pattern are the same i theoretically
should be able to machine the bellhousing to 16" size or am i missing something??
i know thera a 14" flywheel that i can buy but they are expensive and not easy to get hold of here in sweden. But i have acess to machining for free thats why im thinking of going the hard but cheap way.
 

Bondo

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Re: 4.3 bellhousing for 16" flywheel

or am i missing something??

Ayuh,.... Where'd you get a 16" flywheel,..?? What's it off of,..?? Not a 4.3l, that's for sure...
Chevy has always used either the 14", or the 12" flywheels, depending on the starter bolt pattern...
And,...
You absolutely need the flywheel that matches the balance of the motor, especially on the 4.3l...
They've been balanced to match the crankshaft balance,...
 

Technorunner

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Re: 4.3 bellhousing for 16" flywheel

thanks for the quickreply
its a manual transmission flywheel 167 teeth if im not misstaken for a 4.3 from a scrapyard
and the Engine has its origin in a chevy Astro.
the weight on the flywheel matched flexplate and converter for balancing according to scrapyard anyway.

But isent a 4.3 with balanceshaft less sensistive regarding flywheel and the dampner in front?

all info that im getting before the engine is in the boat is great then i can build the engine to last instead of remove it and change its crankshaft after half a season :)
 

zbnutcase

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Re: 4.3 bellhousing for 16" flywheel

thanks for the quickreply
its a manual transmission flywheel 167 teeth if im not misstaken for a 4.3 from a scrapyard
and the Engine has its origin in a chevy Astro.
the weight on the flywheel matched flexplate and converter for balancing according to scrapyard anyway.

But isent a 4.3 with balanceshaft less sensistive regarding flywheel and the dampner in front?

all info that im getting before the engine is in the boat is great then i can build the engine to last instead of remove it and change its crankshaft after half a season :)

Thats 168 tooth, and thats a 14 in flywheel. And no, ALL one piece main seal 4.3's are externally balanced, and require the CORRECT flywheel and damper.
 

Technorunner

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Re: 4.3 bellhousing for 16" flywheel

Ahhh thx a mil for that info. I was sure it was 16" so thats really good to hear. So what i realy need to do is buy a dampner from a car with manual trans. then with the same flywheel and i should be fine??
Is the balanceshaft a counterpart for the camshaft alone??
 

Bondo

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Re: 4.3 bellhousing for 16" flywheel

So what i realy need to do is buy a dampner from a car with manual trans. then with the same flywheel and i should be fine??

Ayuh,... You need the harmonic balncer that matches the flywheel that matches the crankshaft of your motor....

4.3ls are an odd bunch,+ these need to be kept together... They're very Vintage specfic..

The balance shaft is somewhat irrevelant, except that the harmonic balancer, 'n the flywheel, 'n the crankshaft All have to match...
 

Technorunner

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Re: 4.3 bellhousing for 16" flywheel

he he much to keep track of on this kind of engine, really hope its worth it when its in the boat :)
 

Technorunner

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Re: 4.3 bellhousing for 16" flywheel

Ayuh,... You need the harmonic balncer that matches the flywheel that matches the crankshaft of your motor....

4.3ls are an odd bunch,+ these need to be kept together... They're very Vintage specfic..

The balance shaft is somewhat irrevelant, except that the harmonic balancer, 'n the flywheel, 'n the crankshaft All have to match...

would this be an alternative since this seems to be an "active" balancer??
 

Bondo

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Re: 4.3 bellhousing for 16" flywheel

would this be an alternative since this seems to be an "active" balancer??

Ayuh,... The balancer is Active, but you still need the Right harmonic balancer for the flywheel, for That particular Crankshaft...

If you Mix, 'n Match with a 4.3l,... It'll rattle itself to pieces...
 

coheej

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Re: 4.3 bellhousing for 16" flywheel

The 168 tooth flywheel for the one piece rear main seal V6 should be interchangeable with the 168 tooth flywheel for the one piece rear main seal SB V8, at least up to the 96 - 98 years. The harmonic balancer is not interchangeable with the SB.
 
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