my heads are freshly resurfaced but the block is not.
the little info sheet with the gaskets says that with a less than perfect finish youll want to use a sealer. Should I use one? and if so, what should I use?

this is a 305, around 9.75:1 cr with 416 heads

 

i use k&w copper sealer i na spray can for ead and long intake gaskets, works great never ad a problem

 

cool deal, Is the amount to spray something they cover in the directions for it?

I take it your H key isnt working lol

 

I normally use permatex copper spray a gasket. Put some paper towels or rags in the cylinders, then use it like spray paint. Don't forget to remove them after sprying. Depending on circumstance. I 1st spray the block and the upside of the gasket. Don't go crazy with it. Just let it setup where it feels tacky but doesn't come off on your finger (test on an outside corner). It's also easier to use guide bolts when using the copper spray. Get 2 long enough bolts or old head bolts, grind the heads off and put a slot in them. Screw them in the heads, place on gasket and then the head will drop right on without damageing the sprayed on surface. Then use a screwdriver to remove the guide bolts.

 

That's a good idea on the guidebolts.... I just ordered those gaskets for my motor (LG4) I'm rebuilding. I still can't decide whether or not to keep them though since I was thinking of throwing in a cheap set of rods and f/t pistons in which would make 10:1, so I might have to get regular gaskets...

 

The factory used steel shim gaskets with flat-tops & 58cc chambers to come up with 9.5:1 CR. Did you shave your heads or deck or something?

BTW, I used those gaskets & Coppercoat spray. I just sprayed both sides of the gasket.

 

No, I haven't shaved the heads. I was using a compression calculator and came up to 10:1 with .015" gasket, .025" deck height, 58cc chambers and a 4cc dish on the flattops. So I'm guessing the f/t's are more than 4cc's then?

 

Stock bore or .030" over?

I forget what cc the valve reliefs are. 13 comes to mind, but 4 sounds familiar.

Pablo, you still on Okinawa? Are you working on the car in a base craft shop? I left there in '76, suspect a few things have changed since then (such as driving on the left), but others haven't (like max speed limit 50 KPH).

 

I never use anything on head gaskets.

Recently thought I'd finally blown a shim head gasket as
others here had warned.
Turned out a piston let go from high speed detonation, and a piece smashed a good sized hole in the cylinder head. What a mess. One ported 305 head bites the dust.

Both head gaskets were intact and not leaking.

I like to use a little RTV on cylinder head bolts.

 

oh no, i left that hellhole about two months ago. Spent 380 days there for a 6 month deployment, was on the MEU on three seperate occasions. It was a long strange trip. THey still drive on the left. The speed limit is like 80 kph on the freeway i think. I never drove there so i dont know for certain.

Im back home though on some leave and then im back out to camp pendleton. What base where you on?

back to the car, I ended up just spraying both sides of the gasket.

CC'ed my heads had like 51-52 ccs, basically up around 10:1 cr. HUGE PERFORMANCE INCREASE even with a port to manifold mismatch since i didnt machine the manifold. First and only run on the GTECHCompetition with a hot motor and a rocker arm that got loose on the run 13.62@103.85
2.36 60 foot spinning all through first

not bad for a 305 eh!

13.5 is coming with a minor adjustment or two (rockers and more air in the airbags)

 

and Fbird, I feel your pain man... 1 ported 305 head doesnt sound like much to most people but I know what it is to sit there and grind on the things for hours and hours and hours and hours.

 

It's stock bore.

Pablo, those are good times, what are the specs on that motor?

 

its a no name rebuilt 305 shortblock that i found in a parts car I bought, dished pistons
heads are 416's I ported, 3 angle valve job, undercut valves (stock sizes), milled, .015 shim gasket
10:1 cr
No name (SSI) 214/224 cam with 1.6 RR's .474/.498 lift
edelbrock torker II single plane
Edelbrock 1405 600 cfm carb sans choke
crankshaft wiper
edelbrock headers and 3" exaust
T5
3.42 gears


Even with the intake port mismatch that I will have fixed with machining shortly I am going to be bold and predict that I will run a 13.4 tomorrow night with a mph north of 104.5
(was reviewing some earlier runs and conditions to lead me to this.. we shall see)

 

Sounds about like my build, but I'm using a Holley Street Dominator (old school single plane style) and probably a Holley 750 dp jetted down. I'm looking for low 14's from it, but I would be estatic if I would get high-mid 13's.

 

i would upgrade that carb to get the most out of your motor. a 600 with a single plane intake and that cam...i think you need a bigger carb.