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Discussion Starter · #1 ·
I am planning on rebuilding the top end of my 400SB. This will require a lot of minor miscellaneous parts that I want to make sure I have. So far, I know that I will need gaskets and bolts.

Gaskets: Head, intake, exhaust, valve cover, water pump (for a new one), water neck.

Bolts: Water pump, intake, exhaust, head. (are some of these ok to reuse or do all have to be replaced)

(LET ME KNOW IF I AM MISSING ANY ON MY LIST)

What type of gaskets are durable and long lasting for a 400SB? Fel Pro has hundreds of different 400SB gaskets, and I just want to know of one that is affordable and bulletproof. I know Corteco makes a 400 head gasket line too.

The engine is going to be set up for street use, but have the ability for an occasional drag race. I am overwhelmed when it comes to "head" gaskets for my 400. The wall at my local parts store is just covered with them, which makes it difficult for me to know exactly what I need. If anyone has the product # of a good Fel Pro gasket, or even a different brand would be ok, please let me know.

Thanks

So-Cal Jack

P.S. Is there a website that can guide me through this build??
 

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The list of regular small block head gaskets is yes, huge. But the list of 400 specific gaskets is actually pretty small. Small block 400 gaskets are differant and have the provisions for steam holes. If you have iron heads, the cheapest way out is to just buy a FelPro "KS" series kit that contains the entire gasket set. If you have alluminum heads then you will want head gaskets that have a copper fire ring so that the heads won't brinnel.

Good Luck :D
 

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Discussion Starter · #3 ·
Thanks Chris, I'll definitely look into that KS series. I did have to get my heads drilled for the steam holes, so I'll stick with the Fel Pro gasket line.

I'm going to try to do your friend's 400SB build specs, and see how much of an improvement I get from this. I still would feel more comfortable if there was a guide to follow for this job.

Thanks

so-cal jack
 

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Discussion Starter · #5 ·
Doug,

What gasket product # are you using for your Camaro? I have no idea what my quench is. I like the way your Camaro sounds. Do you have any other sound clips of it?...driving, racing, etc???

I think the 280H will be a great cam for my 400SB.

So-Cal Jack
 

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Jack, quench is the assembeled distance between the top of the piston, and the flat portion of the head. To measure your quench you need two diminsions. The deck clearance, and gasket thickness. To measure deck clearance,,, You can bridge the bore with a straight edge, bring the piston to top dead center and measure the clearance with feeler gauges. Make sure everything is clean and make absolutely sure the piston is at TOP DEAD CENTER,,, then measure carefully. You want to measure at the centerline of the wrist pin to eliminate any piston rock that may influence the result. Typically for the unmolested smallblock the deck clearance is 0.025", but that is an average,, you really need to measure what YOUR combination of parts yields. If the block has ever been decked or if the rods have ever been resized, it alters that measurement.

Every gasket FelPro makes lists a compressed nominal thickness. Typically 0.039" to 0.042" for the Permatorque 'blue' composit gaskets. FelPro makes a few ultra thin gaskets down in the 0.015" range, and most steel shim gaskets are 0.015" to 0.022".

Quench is the total of these two measurements. Deck clearance + gasket thickness. Now here's why it's important. A motor assembeled with a large quench will be more detonation prone than one that is assembeled with a small, tight quench. The 'ideal' quench for our small blocks would be 0.035" which would allow just enough room for rod stretch at higher rpm's. But you can see that it is a tough number to hit when deck clearance is 'typically' 0.025", and gaskets are 0.040". There are millions of cars out there with 0.065" + quench that run, and run just fine. And there are also millions of cars out there running in detonation, and detonation is one of your engines worst enemies.
The tight quench promotes turbulences in the combustion chamber as the air/fuel mixture is forced out of the quench area, turbulences help promote a more efficient burn of the fuel, and fights off detonation. So if a large quench makes a motor more detonation prone, and a tight quench helps fight off detonation and makes the burn more efficient (which = more power per pound of fuel burned) You can see it's importance.

Just a few other things, you can not calculate your true compression ratio unless your deck clearance and gasket thickness is known. Don't buy into the advertised compression ratios listed on web sites and car rags. The deck clearance and gasket thickness can make a HUGE difference in final compression ratio. (have I convinced you to go out and measure your deck clearance yet??)

And a final note, you mentioned Corteco gaskets. Be cautious here. They are a very good gasket, but the finish on the heads and deck surface MUST be flat, and the 'right' smoothness, or the gaskets will fail. If you are not having the block decked and the heads milled, and your machinist doesn't finish the surfaces knowing that your using Corteco gaskets,,, I'd highly advise you to stick with a regular ol FelPro composit head gasket. IMO they are the most forgiving gasket on the market today.
 

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Discussion Starter · #8 ·
Doug,

For some reason I can't open the link to your clips. Can you post them on putfile..like your other one?

What is your opinon on the Comp Cam XE274H compared to the 280H?

thank you Marv and Doug for your time, and advice.

So-cal Jack
 

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Discussion Starter · #10 ·
Thank you Marv for the information....and "yes", you have convinced me to measure the quench. :) I'll stick with the Fel Pro line for gaskets.

Doug, nice camaro. It sounds great, nice idle, and revs good. Thank you for your time with the clips. How long have you been running that setup with the 280? Does it require any routine maintenance with the heads, valves, and springs? I don't think I will be running mine at the track often. It will be more of a weekend car, with an occasional drag here and there.

thanks

so-cal Jack
 

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In 10+ years it's broke 2 valve springs (not same ones or at same time) may have over rev'd ? (spring were good to .500 lift and the 280H is .486 lift with 1.5 rockers)
Hyd. cam for the street and guy who doesn't want to be under the hood every weekend is the way to go.
The 280H will put a smile on your face, and a pucker in the pants first few times out. With regular radials and under 30-40mph (speedo is off some) kick it down to 2nd and tromp.... it was sideways :D
I was running a 2200 12" stall converter which I would recommend being your next upgrade (2000 to 2500 or somewhere in-between)
 

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Discussion Starter · #12 ·
Thanks for the info. 10 years with the 280H is convincing enough!! Now it's just finding the best deal on one..:)

So-cal Jack
 

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Discussion Starter · #13 ·
I am about to disassemble my engine to install new heads. The part that I am hesitant about it the removal of the distributor. What is the best way to remove the distributor, remember the cylinder each of the wires lead to, and know what position to re-install it at? I know many of you have been in my shoes, and I would like to know the steps you used. A webpage and guide would be great too, if there is one.

Please help me feel comfortable attacking this task.

thanks

So-Cal Jack
 

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Discussion Starter · #14 ·
I am about to disassemble my engine to install new heads. The part that I am hesitant about it the removal of the distributor. What is the best way to remove the distributor, remember the cylinder each of the wires lead to, and know what position to re-install it at? I know many of you have been in my shoes, and I would like to know the steps you used. A webpage and guide would be great too, if there is one.

Please help me feel comfortable attacking this task.

thanks

So-Cal Jack
 
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