C3 72 exhaust donut ?

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Jul 26, 2019 | 09:26 PM

Pitts532M

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From: Texas

C3 72 exhaust donut ?

replacing heat riser valve on right side, figured I'd replace donut. Looking at diagram the donut fits between bolt flange and sleeve lip mounting to riser. How does that happen? Is there enough wiggle room to get donut over sleeve lip? 72 small block. Thank-you.

Jul 26, 2019 | 11:56 PM

Hammerhead Fred

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From: Midlothian VA

The donut goes on the sleeve an the sleeve is then pushed into the pipe. The flange then pulls the pipe + donut + sleeve tight against the heat riser.

Jul 27, 2019 | 09:20 AM

Pitts532M

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From: Texas

Quote:

Originally Posted by Hammerhead Fred

The donut goes on the sleeve an the sleeve is then pushed into the pipe. The flange then pulls the pipe + donut + sleeve tight against the heat riser.

Hamerhead Fred; thank-you that was what I was afraid of. I have not taken it a part yet, maybe it will become clear when I do, so please excuse my ignorance. The exhaust looks like it is a 2 ½ that reduces to 2” at the riser valve, so it seems I need a sleeve at the donut that fits into the exhaust.

Jul 27, 2019 | 05:03 PM

firstgenaddict

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IF you do not have the sleeve the donut will crush "too much" and will not seal up correctly.

Jul 28, 2019 | 02:23 PM

Hammerhead Fred

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From: Midlothian VA

Quote:

Originally Posted by Pitts532M

The exhaust parts are available in both 2.5 and 2.0 inch diameters. You need to determine which system you have before purchasing.

Jul 28, 2019 | 02:31 PM

Nowhere Man

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also this is a VERY common part found at any auto parts store or exhaust shop

Aug 24, 2019 | 12:50 PM

Pitts532M

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From: Texas

no sleeve for the doughnut, bad seal. Got her with properly attached now. Thank-you.

Aug 26, 2019 | 01:10 PM

carriljc

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Pitts532M

Take a look here.... I did this replacement last year... you should really use the SLEEVE per Willcox.... otherwise it looks like you'll burn up the donut (packing).

https://www.corvetteforum.com/forums...downpipes.html

Last edited by carriljc; Aug 26, 2019 at 01:12 PM.