[Houman SS '70]

Dear Hot Rodders,

I'm going to change my 350 SBC block which belongs to 1975 with two piece rear main seal to a 350 SBC with one piece rear main seal which is 1986-up.

I was wondering if I should also change my TH-350 to a newer version?
What else is required?

Thanks to every hint and everybody.

Houman

[302 Z28]

To my knowledge the older TH350 will work fine with the newer SBC. If the original TH350 is giving you hints that it is about to go south, I would keeep it. Of course if you already have a fresh TH350 then go ahead and change it.

Vince

[MI2600]

You'll need a one-piece flexplate.

[Bumpstick]

You'll need a one-piece flexplate.

...???

Think you mean a flexplate that has the "H" weight for the late model 1 piece seal engines...? (get a flexplate for the 87 and later 350)

[Houman SS '70]

Thanks to everybody.

So the flexplate is different?
How about the converter? I'm going to get a TCI Streetfighter. Does it work?

Tks,
Houman

[MI2600]

The crank flanges are different and won't accept the older style plate. I believe it does have a kind of an H on it. Either will bolt up to your converter.

[jimfulco]

My transmission man recommends the use of a heavy-duty flex-plate on the one-piece Chevys. He said the stock ones have a habit of breaking.