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is that flange rotted through right below the water passage on the left front of the manifold? if so, there is your water. 781 heads. 396. can you see piston domes through plug hole? this may be a seriously low compression engine with those big *** chambers on the smallest BBC. with 25cc dome, .041 gasket and .020 deck clearance i get 8.5:1.
Intake manifold chamber pics :
I'm assuming your question was regarding the 2nd picture?
this pic. bottom left looks like a hole next to the water passage. later pic above looks like it is a dirty spot. massive water in the oil pan is always a failed intake gasket. or a hole in something. head gaskets usually blow coolant out the exhaust. this is a 2 bolt cast crank engine. so a 325 hp 396. those heads cost 2 points of compression.
this pic. bottom left looks like a hole next to the water passage. later pic above looks like it is a dirty spot. massive water in the oil pan is always a failed intake gasket. or a hole in something. head gaskets usually blow coolant out the exhaust. this is a 2 bolt cast crank engine. so a 325 hp 396. those heads cost 2 points of compression.
I believe you're right on the engine/HP numbers. I remember looking it up when I got the car.
I'll clean up the intake a bit later, but I don't remember seeing any glaring holes or issues.
Since I already have the one head off, I'm going to just finish the job and replace both head gaskets (since I already have them). But a few questions:
I'm going to use ARP head bolts. I plan on also using ARP thread sealer. Good choice?
I'm using a felpro BBC gasket kit, I'm assuming I'm putting these head gaskets on with no sealant? Just the dry gasket -
The gasket kit I have has an intake gasket for oval ports, but I've read I need to use rectangular gaskets? Any help on where I can find the right gasket for my application? Also, does the intake gasket go on with any sealant?
I have to ask... Why spend the 3x extra on ARP bolts here? What benefit would they possibly serve on such a low compression engine over stock? Id be putting that into smaller chamber heads myself.. like these? https://www.ebay.com/itm/29353159455...QAAOSw9W5bXMJJ
Last edited by augiedoggy; Jun 4, 2021 at 08:10 AM.
I believe you're right on the engine/HP numbers. I remember looking it up when I got the car.
I'll clean up the intake a bit later, but I don't remember seeing any glaring holes or issues.
Since I already have the one head off, I'm going to just finish the job and replace both head gaskets (since I already have them). But a few questions:
I'm going to use ARP head bolts. I plan on also using ARP thread sealer. Good choice?
I'm using a felpro BBC gasket kit, I'm assuming I'm putting these head gaskets on with no sealant? Just the dry gasket -
The gasket kit I have has an intake gasket for oval ports, but I've read I need to use rectangular gaskets? Any help on where I can find the right gasket for my application? Also, does the intake gasket go on with any sealant?
Thanks a bunch!
Throw that intake in the trash or hang it on your wall....I would not bolt that back on an engine. Look at the water passages and the corrosion....plus it is the wrong port anyway and those didn’t flow worth a damn....look at the dog legs in the runners to clear the intake bolts....terrible.
Stick a Torker 2-0 on it....plenty for a 396....and it will clear the hood....
Use the 1210 intake gasket that blocks the heat riser as I mentioned above.....oval port intake will use oval port gaskets....as designed.
Use a bead of silicone on the front and back rails....Google up some videos, plenty of them.
A Mr. Gasket 1131g is .020 thick and will boost compression a bit....you are kinda weak in this area at just over 8:1 or so.....spray it on both sides with Hi-Tack Permatex....these will work fine with Cast Iron heads....
ARP bolts aren’t excellent and yes, their sealer is very good....Permatex makes the same exact stuff too....PTFE thread sealer.
Use a 3M Roloc Bristle disc (green) to clean the surfaces....best product ever....works great.
This is what I would do we’re you to bring this to me......
I have to ask... Why spend the 3x extra on ARP bolts here? What benefit would they possibly serve on such a low compression engine over stock? Id be putting that into smaller chamber heads myself.. like these? https://www.ebay.com/itm/29353159455...QAAOSw9W5bXMJJ
I have to agree here too....the bolts are overkill....clean up what you have....but ARP are premium. Your call.
I agree on finding a different head too....a closed chamber head.....the increase in compression is worth it.....the 781 head is one of the most desirable heads out of all of the GM heads and you will have no trouble selling them.....
Oval port closed chamber heads and a new intake will wake this right up.....
100 buck torker 2 in north wales PA. he doesn't know what it is, but the number on underside says irt is a torker 2. only oval single plane that fits under a vette hood. he has a set of heads these are port matched to. doesn't say what. https://philadelphia.craigslist.org/...313527980.html Gen 6 L29 heads are cheap and easy to find. 100cc chambers. they are a little restrictive, but good for everything but full throttle above 6000 rpm. would have to do adjustable rocker studs. they make em for those 3/8ths threads. rt 57 salvage in port murray has some for 125 bucks each. here is a pair of 702's down in s. jersey by me. https://southjersey.craigslist.org/p...321920757.html
Last edited by derekderek; Jun 4, 2021 at 09:27 AM.
I have to ask... Why spend the 3x extra on ARP bolts here? What benefit would they possibly serve on such a low compression engine over stock? Id be putting that into smaller chamber heads myself.. like these? https://www.ebay.com/itm/29353159455...QAAOSw9W5bXMJJ
Originally Posted by Jebbysan
Throw that intake in the trash or hang it on your wall....I would not bolt that back on an engine. Look at the water passages and the corrosion....plus it is the wrong port anyway and those didn’t flow worth a damn....look at the dog legs in the runners to clear the intake bolts....terrible.
Stick a Torker 2-0 on it....plenty for a 396....and it will clear the hood....
Use the 1210 intake gasket that blocks the heat riser as I mentioned above.....oval port intake will use oval port gaskets....as designed.
Use a bead of silicone on the front and back rails....Google up some videos, plenty of them.
A Mr. Gasket 1131g is .020 thick and will boost compression a bit....you are kinda weak in this area at just over 8:1 or so.....spray it on both sides with Hi-Tack Permatex....these will work fine with Cast Iron heads....
ARP bolts aren’t excellent and yes, their sealer is very good....Permatex makes the same exact stuff too....PTFE thread sealer.
Use a 3M Roloc Bristle disc (green) to clean the surfaces....best product ever....works great.
This is what I would do we’re you to bring this to me......
Jebby
Replying to both of you --
Im not planning on keeping this engine long, maybe 1 year (next year?), 2 max. So performance and all that at this particular point isn't really high on my priority list. I'm just trying to get it running at this point. As far as the ARP bolts, Ive just used them on every engine I've built, so it's kind of a habit. I don't want to reuse the old bolts and if I'm buying a new set, I'd rather get something worthy. Only a few extra bucks.
Honestly I didn't really plan on digging in the motor this far to begin, but since I'm here I'm just doing some PM to make it as reliable as possible for the 1000 miles I may put on it before I buy a crate
Im not planning on keeping this engine long, maybe 1 year (next year?), 2 max. So performance and all that at this particular point isn't really high on my priority list. I'm just trying to get it running at this point. As far as the ARP bolts, Ive just used them on every engine I've built, so it's kind of a habit. I don't want to reuse the old bolts and if I'm buying a new set, I'd rather get something worthy. Only a few extra bucks.
Honestly I didn't really plan on digging in the motor this far to begin, but since I'm here I'm just doing some PM to make it as reliable as possible for the 1000 miles I may put on it before I buy a crate
Make sure you put a new intake on this or you will be very unhappy. The intake is way more important than the head bolts for a few extra bucks....
Quick update -- good news and bad news
A buddy I met at a car show a while back has a BBC torker 2 he's not using... Apparently they don't have the best rep as the best flowing? Haha
Installed the pass side head back today. Everything was good. Bolt 16, the last bolt... Stripped threads. Held to 60 ft lbs tq. Went to the last step of 75-80 ft lbs and it gave. So I had to uninstall the head and ordered a helicoil. Wasted a whole day haha but I guess that's how it goes. Hopefully I dont have any issues with the driver side tomorrow.
New intake manifold looks good. I CHASED the remaining head bolt holes with a thread chaser. Lots of gunk in there...
The helicoil should be here tomorrow.
The only question I have is... Hoe do I drain the remaining coolant out of this block? I searched all over the internet but I can't find a concrete answer. I pulled what I thought was the drain plug on the pass side, but nothing came out. I'm assuming there's a drain on the driver and pass side? Can the drain be seen in the (driver side) picture I've attached? If not, a specific image with the plug highlighted or circled would be great. Thanks guys!
Did you rotate the block so that the hole is at it's lowest point?
Next...the hole may be blocked with crud...stick a screwdriver into the hole to see id crud and coolant pour out (into a bucket).
