head gaskets year usage

[skostur79]

in the process of freshing my engine

but im looking at gaskets and 85 and 87 head gaskets are different?

the gm 85 gaskets are discontinued and are not the same number as 87's

so can i use 87 gaskets felpro decent ?

i have 8445 casting heads

thanks,

 

[cool 84]

You can run 87 gaskets. They're thicker and composite vs steel shim. The 85 gaskets are a little harder to blow. You will lose a slight bit of compression and it will give you a little less lifter preload. I'm not sure how well the composites work with the stock 85 head bolts.

 

[6SENSE]

Ive been using GM 87 gaskets that I purchased locally from dealer for awhile. Have worked fine other than the already mentioned decrease in compression which may give a slight decrease in gas mileage and on the street driveability as far as initial get up and go. As also mentioned lifter preload will undoubtedly change using your same pushrods. Not critical enough to cause any problems though from my experience.
I have never blown one with as much as Ive experimented with and pushed my car.
Reason behind different thickness in gaskets between years is the deck height of the blocks. Heads are the same but the deck height is lower on the 86/87 blocks needing the thicker gaskets to acheive the same compression ratio (.060 thickness compressed vs .017 or .019 I think).
Order a pair of the Felpro 1000 gaskets. They fall somewhere in between as far as thickness (.030 or so) and much better than the ones offered at the local parts store, which by the way if you check are the same that they are selling for the NA engines.

 

[skostur79]

i forgot to say that i did take off composite gaskets
i tryed to look for a companys stamp on it but did not see one yet

so the only difference is the thickness right?

do any know why felpro has different part numbers for 85 vs 87 head gaskets?

 

[Lee Thompson]

Fel pro 1000==.040 thick compressed
That is the Felpro you need. They have some cheaper ones that you DO NOT want to use.

 

[tpivette89]

the gm 85 gaskets are discontinued

since when? i ordered a set from a local Pontiac dealer last year for my hotair rebuild. they didnt have any in stock, but they were found at another dealership and were shipped to my shop the next day

 

[skostur79]

the felpro 1000's is there a web site where i can buy them
my parts store are ran but morons for i prefer to but them on the web

detroit gaskets ? any one here use them?

 

[6SENSE]

Detroit gasket = NO

Get the Felpro 1000 from Summit or Jegs or..........
84/85 GM (from GM dealer) are available last time I checked. I bought 1 pair a year or two ago from the dealer. The difference between 84/85 and 86/87 gaskets is the material (steel vs composite), and the thickness. Thickness is going to be your main factor.
I would narrow your decision to the GM 84/85, GM 86/87 or the Felpro 1000. Due to factors already discussed I think the Felpro 1000s are going to be your best all around choice.

 

[Lee Thompson]

here you go !!!

Call this # and ask for Scotty--nobody sells parts cheaper than
SRS Engine Parts
800-333-7113
Greenville, Ohio
They will be drop shipped to your door in 2 days.
Again, Felpro 1000 is the gasket you want to use.

 

[skostur79]

i take it 1000 is the product line

i found this set a summit

that right i hope

FPP-1026 Fel-Pro Performance Head Gaskets
Head Gasket, Composition Type, 4.090 in. Bore, .039 in. Compressed Thickness, Buick, 3.2/ 3.8/ 4.1L, V6, Each

thanks everyone ill add it to my list

 

[Lee Thompson]

wrong one!!!

Felpro 1026 is not the gasket you want unless you have a 4.020 in. plus bore.
Once again you want Felpro 1000.
1000 is the Felpro part #

 

[cool 84]

I never thought about running the 1000 on the 3.8. I can say the 1000s have held up to some serious prolonged detonation on my car. I don't know how they're not blown. Definately a great gasket.

 

[alec296]

ta catalog lists the steel shim head gaskets for 39 bucks
andy