Can I use a sb400 flexplate on a sb350
 

Getting ready to install my engine & trans & I have a flexplate question. I have several flexplates in my stash, however they all appear to be balanced. I say that because they have several extra drilled holes which I am assuming is for balancing.

My question is can I use 1 on the 350 engine I am installing? Seems to me that a balanced flexplate wouldn't do harm to a 350 but visa versa would be a problem (unbalanced on a 400 engine).

Any input would be appreciated. We all know what happens when we assume.

Thanks
Scott

Re: Can I use a sb400 flexplate on a sb350
 

No. External balance 400
internal balance 350.
The 400 should have a large counter balance weight

Re: Can I use a sb400 flexplate on a sb350
 

Thanks 4 the input. The other flexplates I have do have counter weights, but this 1 only has the extra holes.

Here are a couple pics:

Re: Can I use a sb400 flexplate on a sb350
 

ttt

Re: Can I use a sb400 flexplate on a sb350
 

"they have several extra drilled holes which I am assuming is for balancing."

On a flex plate with weights you will actually see a chunk of metal welded on that is the weight.

Re: Can I use a sb400 flexplate on a sb350
 

I'd buy a new one that hasn't been messed with.

100-2901 bolt kit

SCAT Engine Components FP-350-SFI - Scat Flexplates

Re: Can I use a sb400 flexplate on a sb350
 

I think the holes were drilled to balance the TH350 flexplate. I mean, even with an internally balanced engine you would want the flexplate fairly balanced. The TH400 ones are "counter balanced". No weights = TH350.

Re: Can I use a sb400 flexplate on a sb350
 

So, looks like I can use this 1 on a 350/350 combo?

Will probably just go buy a new 1 but would like to know incase I need it in the future.

Thanks