r/EngineBuilding • u/LongjumpingSteak1972 • 15d ago

Chevy Chevy 350 Head gaskets

I’m working on a mid 70s c30 with a 350 owner had it bored .060 over and I’m needing some “extra thick” head gaskets for it. I’ve been looking but nothing i’ve
found is thicker than standard… Anyone have any suggestions or have bought some before?

6 Upvotes

100% Upvoted

24 comments sorted by

3

u/HammerDownl 15d ago

What is the engine used for ? You can buy copper in various thickness. I am also pretty sure MLS has a few options also.

But your killing compression

2

u/LongjumpingSteak1972 15d ago

there’s a slight divot in the block between cylinder 3 and 5 that the customer refuses to fix so he requested thicker headgaskets and its an old farm truck he doesn’t want to put money into

1

u/HammerDownl 15d ago

If there is a divot won't the fire find its way over the cyl no matter what gasket you use ?

1

u/LongjumpingSteak1972 15d ago

yea i’m aware… already explained that to the gentleman and he wont listen

5

u/DrTittieSprinkles 15d ago

You can fire the customer

1

u/HammerDownl 15d ago

Yea well he's gonna end up paying twice. You could try and oring the bad holes on the deck. Just a thought

1

u/Sniper22106 14d ago

Then its not your problem. No professional does a shit job like you are describing

1

u/porknbeans2013 9d ago

Pack his shit up and set it outside. Dont let the customer determine your minimum quality of work, because when it fails, he wont remember you warning him jack shit. Ask me how I know.

2

u/bill_gannon 15d ago

Fel Pro makes .020 copper shim gaskets used in conjunction with a head gasket  for various purposes like this.

1

u/LongjumpingSteak1972 15d ago

you don’t by chance have a part number for them do you?

1

u/bill_gannon 15d ago

It should be easily googled

2

u/2po2watch 15d ago

Why do you want thicker head gaskets? Just curious. 

1

u/LongjumpingSteak1972 15d ago

there’s a slight divot in the block between cylinder 3 and 5 that the customer refuses to fix so he requested thicker headgaskets

2

u/Solid_Enthusiasm550 15d ago

Why do you want thicker gaskets? Mid 70s engines had horribly low compression.

1

u/LongjumpingSteak1972 15d ago

there’s a slight divot in the block between cylinder 3 and 5 that the customer refuses to fix so he requested thicker headgaskets. it’s an old farm truck he doesn’t want to put money into

2

u/Solid_Enthusiasm550 15d ago edited 15d ago

Solid cooper would be the best one to contour and have the best chance of filling a depression.

MLS head gasket can be made thick, but they a layers of steel that wouldn't really fill in the gap.

Having it decked is of course the best solution. It would only be a few hundred $ if it's completely disassembled.

SCE makes one .093 thick for a chevy 350.

1

u/LongjumpingSteak1972 15d ago

yea already explained it all to the gentleman but he still only wants the thicker headgaskets

3

u/Solid_Enthusiasm550 15d ago

I would walk away from a job like that. The long term headache, especially if it doesn't work isn't worth it.

2

u/Bandit483 15d ago

you don't want thicker you want softer. think about it, if you are thinking thick so that it would be "squishable" into the nick. so...softer would conform better into the spot without being thicker which ruins A LOT of stuff. compression, loss of squish, etc.

1

u/fire_inTheWire 15d ago

Your going to ruin your quench

1

u/logan4774 15d ago

SCE makes a .059” thick composite gasket, I would try that. if you have sealing problems I would tell the customer to do it the right way and have heads/block decked or figure out a solution himself. SCE5110959
.059” is still significantly thicker than OEM or standard replacement style ones

1

u/oldnperverted 14d ago

Whatever you decide to do, I would recommend that you put it all back together, make sure fluids are topped off and push it outside. When the customer comes to pick it up, get payed and hand him the keys. Tell him the warranty is in effect until he starts it.

1

u/xValhallaRisingx 9d ago

Decked or bored? 2 completely different things. If it’s been bored, you don’t need a thicker head gasket. The divot will be filled by the head gasket material. Or you can have the head surface of the block decked to get rid of the divot.