Regarding the valley on my 340 - there's two small pins pressed into the front valley and one in rear with corresponding holes in the cork gaskets - I need to pull these out to get proper alignment with the Air Gap - plan on silicone only on front/rear. I'm assuming this is fine ?
Intake manifold "guide" pins
- Thread starter rebeldart
- Start date
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YES! Take'em out and throw them away. They may interfear with the intake sitting all the way down like it should.
swinger1969
Repeat Mopar guy
Just curious but having built several streetrods using factory parts like Mustang IFS , stock engine parts etc etc because " they have ironed out the problems at the factory so why re-invent the wheel", why do guys throw away the gaskets, pull the line up pins out, and run a bead of silicone all in place of what worked on so many cars from the factory? Why would they have the pins there if the manifold "might not set right" , and why would they use front and rear gaskets if they didn't work? Not meaning to knock anyone's ideas but wondering why. I'm in the prcess right now of installing an RPM Air Gap on my 340 and wondering about this now. Thanks!
When you do your manifold swap, get back with us and see if you feel the same way.
Why the cork gaskets failed... The weakest point in that piece of cork is where the pin hole is drilled through. Once the PVC circuit got clogged and/or compression rings began to fail, crankcase pressure would push the cork out breaking it at that weakest point.
To leave the pins and the cork out, and build the seal from silicone makes the pin holes the most anchored point in the seal. Doesn't mean the seal wont push out at a different spot eventually. Excessive crankcase pressure will get out somewhere.
To leave the pins and the cork out, and build the seal from silicone makes the pin holes the most anchored point in the seal. Doesn't mean the seal wont push out at a different spot eventually. Excessive crankcase pressure will get out somewhere.
swinger1969
Repeat Mopar guy
Ahhhhhhhhh, good explanations and I can see why now! Thanks folks!:cheers:
I've always kept the pins and end gaskets with no problem...
Some folks do. There are also redesigned end wall seals that have flanges that go over the end walls and hold the seals in place. My 351M in my Ford truck uses those, along with a bathtub gasket over the intake valley.
swinger1969
Repeat Mopar guy
True, but Mopar doesn't have those as far as I know.
You may be right. When I go into work today I will rummage through the system and see if I can find a set that does.
69_340_GTS
Well-Known Member
When I tried to install my Edelbrock intake on my 340 there was no way to get the bolts started with those cork gaskets in place. Not sure if it comes down to manufacturing tolerances, or what, but I had to use the silicone too.
swinger1969
Repeat Mopar guy
More good info! And did you remove the little dowels as well or leave them?
If the aftermarket intake doesn't have the pin holes, you run the risk of cracking it when installed. Some even say it can happen from using the cork gaskets.
I use the cork, if possible, but that's just me. I do put a bead of silicone on the wall, place the cork on it and set a weight on it and let it set up some. Then another small bead when I drop the intake on. I haven't any issues yet. (fingers crossed, lol)
I use the cork, if possible, but that's just me. I do put a bead of silicone on the wall, place the cork on it and set a weight on it and let it set up some. Then another small bead when I drop the intake on. I haven't any issues yet. (fingers crossed, lol)
I sometimes have trouble starting the first few bolts because the threaded hole is toward the bottom of the clearance hole, but with a little finesse, you can get a couple to start on each side, then after you run them down a bit, the rest go in fine...
Yes, if the aftermarket intake doesn't have clearance holes for the pin, then you should remove it. I still use the end gaskets with gaska-cinch to help keep them in place.
69_340_GTS
Well-Known Member
Dowels came out. I didn't know if they'd hit the manifold or not, but why chance it?
69_340_GTS
Well-Known Member
After cross-threading a couple head bolt holes, I gave up trying. Thankfully, they were not too bad and I just had to chase the threads.
I always chase my threads with a tap/die. It helps especially in cases where you have to "fish around" to get the threads started...
Plus it helps in most cases that you can run the threads most of the way down by hand... Just snug/torque with wrench...
pishta
I know I'm right....
"..........The pins are removed because most aftermarket intakes are not drilled for them. If they are still in the block, they will hold the intake up off the block and even possibly break the intake when it is tightened down, so they should be removed...."
Word, I broke a 273-4 intake trying to torque it down on a 318 WITH PINS.....that obviously the 273 didnt have. Ended up using a Performer 318 that probably worked better anyway. torque-torque-SNAP! WTF?
Word, I broke a 273-4 intake trying to torque it down on a 318 WITH PINS.....that obviously the 273 didnt have. Ended up using a Performer 318 that probably worked better anyway. torque-torque-SNAP! WTF?
swinger1969
Repeat Mopar guy
ALL good points, guys, and much appareciated! Larry :cheers:
I just remembered another trick that I use to get the intake and head bolt holes to line up is to stick a phillips head screwdriver into the bolt hole next to the one that I'm are trying to start, and use it to push down on the intake to help align the holes...
swinger1969
Repeat Mopar guy
Good one!
swinger1969
Repeat Mopar guy
Tried getting them out with vise grips but so far no luck - keep slipping off. ( Keeping the vallet etc well covered though !!!)
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