[Tom396]

Til now, I'd only heard about it happening to other people.

Yesterday, I swapped out the intake gaskets on my oval port 396 BBC. I did so because I'd been noticing that they looked kinda odd near the center ports. Turns out, it was good that I pulled the intake. The tops of the gaskets were pulled about 1/4" down into the intake port. Also, the steel shims that were supposed to keep the exhaust crossover blocked were completely burned away. Granted, these gaskets had been in there a long time (9 years worth of street miles and 1,000+ passes?).

These were Mr. Gasket intake gaskets. The name was still visible printed on what was left of the gasket. They were very dark, maybe even black. They have an orange sealing bead printed into the gasket material. I don't know which part number it was. Most of the material is quite soft. I'm sure it sealed up great, when it was first installed.

The gasket slid into two halves. One half was nearest to the head, the other was nearest to the intake. Only one half slid down into the intake tract. The other half stayed where it belonged. I replaced them with a set of Fel Pro 1210 gaskets. I don't think they'll be any problem.

Any of ya'll run into this before with this gasket, or others? Take care. Tom Worthington.

 

[SpeedSceneLiveTV]

Has happened to me before. Just got to find the right gasket set that works for your motor. I went to another brand, (I switched to the Mr Gasket brand from the Fel Pro) and never had a problem again.

 

[SG60IMPALA]

I have the same problem with the Mr.Gasket brand on my 540. I also think mine being on the throttle stop don't help any.

 

[Brad]

Make sure intake matches heads, Felpro makes laminated gasket with steel that works nicely

 

[Real McCoy]

I have seen it several times. Usually seems to be from the intake bolts not being retightened after the motor has been heat cycled several times. Motors with vacuum pumps can do this too. I glue the gasket to the head which has always worked well for me but cleaning it off can be a task.

 

[flyin ryan]

Motors with vacuum pumps can do this too.

I've been having more of a problem with this lately too. Glue or not. Really paying attention to the intake bolts staying very tight. I think vacuum pumps to blame 100%, but can't get rid of those .

 

[JShelton]

Tom I used to run them heads and had the same problem after a couple of yrs! the way i found out was I was noticing a little coolant coming out between the intake and head at the front and rear of the intake surface of head and intake manifold. So I went to check tightness of bolts to find out they were all loose!LOL! So I pulled the intake and found the same thing on the ports like you did so now I'm running a different combination but I check the bolts all the time to make sure there tight and haven't noticed any problems since. Its funny how we take things for granted when we race our daily drivers.

 

[Real McCoy]

I've been having more of a problem with this lately too. Glue or not. Really paying attention to the intake bolts staying very tight. I think vacuum pumps to blame 100%, but can't get rid of those .

I use a FoMoCo glue, don't have the number handy, but if you apply it to both sides of the intake you can pick your entire motor up off the ground with no bolts in it and the intake will not come off. I let it hang on a motor stand, soaking the edge with Gumout ,for several hours before the intake finally broke loose. The gasket will not suck in using it, or it hasn't for me anyways....LOL.

 

[mcintosh]

I pushed my intake gaskets out with boost. Steve Morris recommended Hondabond or Yamabond, this has worked for me.

 

[tsanchez]

Just did a 396 with a air gap last weekend with the mr gaskets pushed out everywhere, put in felpros.

 

[z289sec]

If the exhaust crossover metal plate block off was not in there, that is why that part of the gasket was burnt away. The old Ultra-Seal which is what you had, used to have a round hole right there.If you weren't going to use the divorced choke, there was a metal plate with a button imprinted in it to block off the passage.

Like others have said use a good glue, and a metal embossed gasket and you shouldn't have any issues. I typically use the Fel-Pro's with Permatex High Tack gasket sealer.

 

[Jp outlaw]

Yamabond is the shiznit!

 

[Tom396]

Great responses. Thanks and take care. Tom Worthington.

 

[Nhrakat]

We used to change intake gaskets on our dragsters 3 or 4 times a year because of this. We went to plastic gaskets from nagy performance and never changed them again. They are reusable also.

 

[DoubleRRacin]

Lot's of guys don't run vacuum pumps.
Has anyone seen a blown intake cause the bottom end to build so much pressure that oil is pushed out the evac tubes.....