69 roadrunner 383 engine questions

[welder47]

Just have some simple ? reguarding a 383 engine.
1. Do the exhaust manifold bolts require silicone, they look like they go into the water jacket.
2. Whats the opening above the intake for its located between the center cylinders and isnt covered, hole is on both sides of engine. Refer to picture.
3. Why are the engine mount bolts so small in comparison to the size of the holes in the frame and engine mount locations, seems very sloppy.

 

[northerndave]

Sure that's the right intake for those heads?

looks like an exhaust crossover port to me....

 

[northerndave]

I think there is a void or cavity around the actual crossover port that makes it look like its open or not mating up correctly.

i'm curious for someone else to answer your questions though, especially about the exhaust manifold bolt holes.

Because I seem to be burning a bit of antifreeze on my drivers side exhaust manifold on a cold start up after the car has been sitting for a while. (383)

I have been worrying about a head gasket actually.

 

[detmatt1]

I think there are high heat silicone rtv sealants that can be used to seal the exhaust bolts. As far as the intake, that is the crossover to heat the choke spring and get the engine warmed up faster and get the choke turned off so it's not running rich longer then it needs to. Why it is open around that port on the head, I am not sure, but maybe it's just to aid in heating the engine compartment?
Anybody else?

 

[wannadrag]

I may be wrong but i think the studded exhaust bolts go into the water jacket.And the intake on the 440 in my 70 RR is the same.The hole your seeing is the heat crossover for a factory intake.According to my mopar buddy it doesnt hurt to leave the intake as is.I am sure i will be corrected if i am wrong.lol

 

[detmatt1]

I'm sure that the area in question was not meant to be covered by the intake.

 

[northerndave]

Check it out...

seems to just be a void/cavity around the actual heat riser crossover port.

 

[welder47]

It is the stock intake, and Ive seen pics of the opening still showing on engines, the heat channel is below that area. I do know that the exhaust goes into the water jacket because antifreeze poured out the bolt holes when I had the motor pulled out originally and tipped it sideways. I did see some silicone on the bolts when I removed them but all my books do not say anything about it.

 

[northerndave]

that's pretty awesome for me to hear beacuse i was racking my brain trying to figure out how the hell I was getting antifreeze cooking on my HP exhaust manifolds! lol!!

Betting 99% chance it's a leak past an exhaust manifold bolt/stud.

 

[Propwash]

As Jay said..those are your heat cross over ports.. Some guys leave them open, especially if there is a heat driven carb fuel boil out problem causing hard starting after sitting for a few minutes and they don't have room for a spacer.

Your exhaust manifolds were held on from the factory via studs and nuts/sleeve nuts. If you install bolts, be weary that you will be dumping anti-freeze everytime you pull those bolts out as they do run into your water jackets in the heads, as you found out. High temp sealant usually does the trick to keep a bolt/stud from leaking. I don't know if it's murphy's law or bad luck, but i've always had the big block exhaust manifold gaskets take a crap twice as fast as small blocks, thus I always kept the studs..

As far as the slop in the mounts, what dia. of bolt are they? I'm trying to put an exact size on bolt Dia. from what I ripped out/installed in the past. The bolt heads are 5/8"....Bolt size of 7/16" maybe?? kinda taking a shot in the dark...Anyone elso on bolt size?

 

[welder47]

So Will do ya recognise the intake lol. Looks different all blasted and painted huh. The bolts that fit into my engine mount are 7/16 but the holes on the car frame are about 5/8 and so is the hole opposite the welded nut on my mount on the motor. Maybe its for movement when you mount the motor in the car. I might go with studs on the exhaust if I can see it working with the headman headers I have. And to the other guy, I can definetly see how a engine would burn through some water with just a non coated bolt installed, not a fast leak but big enough to make you think a head gasket was out which is not a fun thing to change out.

 

[welder47]

Now Im going to get out my kids art brush and paint over that raw steel area I so carefully masked around for no reason lol.

 

[Propwash]

Wow Russ......That Intake cleaned up beautifully. You do nice work! Glad it went to a good home!

I tried the using bolts for the manifolds idea once...after the second time of having to dump anti-freeze to change out an exhaust manifold gasket, that was enough of that.

I use a hi temp copper based anti-seize between the studs and sleeve nuts. Not the cheap Fleet Farm special stuff either. Industrial based stuff I get through Airgas. The big problem with the studs is if you're not using an anti-seize or let them get away on ya, they seize up and you either pull the stud out with the sleeve nut or end up snaping the stud off into the head..Makings for a bad friggin day!!!

I'll check the hook up on the roadrunner tonight with the mounts. See if i'm looking at the same amount of play. Pretty sure the Coronet is in the same boat as well.

Thanks for sending over that info on the body seam sealer and again, great work on that intake manifold!

 

[CAPTMACK007]

copper based paste anti sieze is not anti sieze... copper is conductive and that stuff is for increasing conductivity on battery terminals and electrical crimp terminals/connections... omg don't use it for anti sieze it'll do the opposite

As far as the mainifold bolts, I found out about the antifreeze leaking on a road trip..The car was new on the road, and my wife and I were hundreds of miles from home. I kept hearing this hissing when I stopped and found the water was leaking on the drivers side rear bolt after close inspection. I thought about head gasket too.... The bolt was almost falling out! I was lucky there was an AutoZone nearby. I took it there and the clerk noticed it was a METRIC thread... I argued that was impossible..omg..I realized that the prior owner tried to jam a metric into a standard hole.. Luckily, I was able to clean the threads with a tap (in the motel parking lot) and put in the correct size bolt. I use Permatex #2. there is no need for high heat stuff and I really dislike silicone.. Permatex #2 rocks!! Permatex #1 dries hard and #2 remains pliable.

I have the same gap on top my 383 on top.. Edelbrock performer RPM intake. Don't drop the little nuts in there hard to retrieve/ask me howI know

 

[Propwash]

I think you're a bit confused...If it wasn't anti-sieze, it wouldn't say anti-sieze on the bottle. As well as being hi temp (18ooF), it is also corosion resistant. Description on the back says works well for high temp and high torque applications as well general corosion prevention. I've used it for years on all kinds of applications as well in the USAF on F-15E's. Good enough for a jet..Good enough for me. Heck, google the cheap Permatex copper anti sieze and it'll probably tell you the same thing. I'm not quite sure what product you're talking about. More of a electro-conductive type product sounds like

 

[CAPTMACK007]

well if you dont know what a battery is..."two diff metals touching or close enough to pass and flowing electrons" and that is what electrolysis is (A chemical reaction) and corrosion is the result. Use that stuff on similar metals fine. You go and sink a stainless screw in to aluminum and let me know how long before the copper allows the aluminum to give up it's free electrons to the stainless (annode / cathode) creating a hole..... Anti sieze pastes MUST be non conductive. sheesh
Evil Emperor talking to Luke; No my young Jedi...you will find it is you..who are confused about a great...many...things...

 

[Propwash]

Yeah, I don't know what a battery is..Thanks for the heads up...I'll spare us the wasted time of a pointless argument on this and just post a link for valco copper anti-sieze. Pay special attention to the discription..

http://www.valco-cp.com/Anti-Seize.htm

Scroll down on the link for MIL-STD Approved Loctite C-5 Copper anti-sieze

http://www.nolansupply.com/superfluids.asp?supercategory=Anti%2DSeize+Compounds

Maybe you could call up the engineers over there and fill them in as well as the US military and let them know they got it all wrong as well..

There..you can have your sarcasm back..

 

[Propwash]

Alright..enough playing swords...


Russ, what brand/amp altenator is that on your 383?

 

[shag766]

jeez it was just getting interesting and then mom made me come in for nappy time

 

[CAPTMACK007]

ok.. and what brand plug wires are those...?
lol