You can do it. As they have said, just take your time.
340 Intake manifold
- Thread starter KennyCuda
- Start date
MoparCarGuy
Well-Known Member
- Joined
- Jun 28, 2020
- Messages
- 726
- Reaction score
- 618
Another video worth watching on intake manifold installation by PowerNation. They are using the Fel-Pro 1213 gaskets, too.
Intake installation starts at 13:40. Click here.
Intake installation starts at 13:40. Click here.
Not sure which intake manifold gaskets to buy they list 3 different port sizes 1x2 3/16 and 1.16x2.27 and 1.43x2.05 . its a stock cast intake 1968 340 engine in it I don't want to buy the wrong ones. i was also told victor makes a good gasket .
MoparCarGuy
Well-Known Member
- Joined
- Jun 28, 2020
- Messages
- 726
- Reaction score
- 618
The head intake port sizes are the same on all factory 340 heads. The intake manifold ports are slightly smaller than the head's intake ports to prevent an obstruction mismatch. You have the option of port matching the intake manifold ports to the intake gasket size for better flow. Good info here about port-matching: 340 X Head Buildup - Mopar Muscle Magazine
340 OEM Cast-Iron Heads =2.27 in. x 1.16 in
The Fel-Pro 1213 gaskets are the correct 340 intake manifold gaskets.
Fel-Pro 1213 Fel-Pro Performance Intake Manifold Gasket Sets | Summit Racing
Free Shipping - Fel-Pro Performance Intake Manifold Gasket Sets with qualifying orders of $109. Shop Intake Manifold Gaskets at Summit Racing.
MoparCarGuy
Well-Known Member
- Joined
- Jun 28, 2020
- Messages
- 726
- Reaction score
- 618
Google is your friend. The best gaskets are rubber. I use Perm-Align gaskets on my 440. No leaks ever.
Moroso Perm-Align Valve Cover Gaskets 93050
Moroso Perm-Align Valve Cover Gaskets 93050
Mopar Mitch
Well-Known Member
Regardless which type of valve cover gaskets you choose, no gasket is better than its installation. Cork-rubber will conform best to any irregularities in the cover and/or head surface.
Rubber is denser and does not conform as well as cork-rubber.
Cork rubber will, in long-term over many years, attract oil and become saturated... eventually needing replacement... maybe in ten years or so.
Rubber gaskets split apart IF they are over-tightened. Rubber does not compress.. it distorts. Rubber is best installed DRY.
Molded steel core silicone gaskets have very little conformance to distortion... flatness is critical. they do not conform well to stamped steel covers.
I'm a former Fel-Pro aftermarket gasket engineer.. and I wrote all the installation instructions (FIT-forms) that are contained in the sets.
Rubber is denser and does not conform as well as cork-rubber.
Cork rubber will, in long-term over many years, attract oil and become saturated... eventually needing replacement... maybe in ten years or so.
Rubber gaskets split apart IF they are over-tightened. Rubber does not compress.. it distorts. Rubber is best installed DRY.
Molded steel core silicone gaskets have very little conformance to distortion... flatness is critical. they do not conform well to stamped steel covers.
I'm a former Fel-Pro aftermarket gasket engineer.. and I wrote all the installation instructions (FIT-forms) that are contained in the sets.
Chryco Psycho
Well-Known Member
I would also port the heads & intake but then I own a die grinder & have been porting for decades !
Mopar Mitch
Well-Known Member
Which intake gaskets (from Fel-Pro)... if you choose to have the exhaust cross-over port open (for manifold heat to warm up the carb during cold operating temps)... then simply use the common MS-90109. the side rail gaskets are metal cored with fiber facings that have raised embossments around each critical sealing area. These gaskets also have a blue Teflon anti-stick coating for a supplementary sealing agent that also acts as an anti-stick for easy removal if/whenever needed. Additionally, this MS-90109 set includes 4-plastic alignment dowels to attach and align the side gaskets into the heads.
IF your intake manifold does not have the center exhaust cross-over port (as many aftermarket aluminum manifolds are)... then you could still use the MS-90109... or else, use the Fel-Pro Performance intake set #1213. Those side rail gaskets are a dense fiber with Print-O-Seal sealing beads around each port; the dense fiber material is good for conformability as some aluminum manifolds have slight warpage and/or corrosion/pitting.
Regarding the search for the molded rubber f/r end seals, forget it... for small block Mopars... many years ago, I'm pretty sure that all gasket companies have already switched to the cork-rubber seals because of their better compression (up to ~50%)... whereby rubber is not compressible... it distorts upon being squeezed... and will commonly split apart beyond ~30% of squeezed. As an option, you could simply apply about 1/4" bead of RTV silicone (any kind, but black is suitable as it will resist the common temps at that location).
Finally, when you install the side rail gaskets, regardless of the F/R sealing you choose, be certain to apply a small dab of RTV silicone at that the 4-intersecting points of the manifold/head/ends.
Before installing the manifold, do yourself a favor and tap the head threading for the intake bolts, as well as run a cleaning die over each bolt thread -- you will be glad you did this (general practice for any assembly).
Here's a tip: On many SB Mopars, there may be front and rear metal dowels -- used to align the end seals as well as the intake manifold. However, sometimes the height of those dowels will cause the manifold to not come down enough upon being tightened, especially if there has been any resurfacing done to the block/heads or manifold. So... best if you just pull them out. Most aftermarket aluminum manifolds do NOT have the small hole F/R for the dowel... so again, best to remove the dowels.
Another tip: As for the plastic alignment dowels (as included in the MS-90109 set), depending on your manifold, it could be an advantage to grind a small relief area (tear-drop relief shape) into the manifold areas that the plastic dowels will be positioned (common 2nd form each end). I've seen OE cast iron manifolds with these reliefs, but never have I seen an aluminum (not the Eddy OE or aftermarket six-packs) having these tear-drop shaped reliefs. The slight raised height of the plastic dowels could, possibly, pending the manifold bolt hole diameter, hold up the manifold from being fully tightened down to the side rail gaskets. Most people are unaware of this matter when using the plastic alignment dowels with their intake manifold.... same scenario with the F/R metal dowel pins.
Final tip: On some aftermarket aluminum intake manifolds (regardless of engine brand), the intake ports may be slightly mis-aligned due to casting shift. The result is that the gasket may not seal properly around the ports... the raised sealing beads (either with a metal-cored gasket or the dense fiber gaskets) could fall uncompressed inside the ports -- not good! So, you have to visually inspect the alignment of the casting ports with the gasket ports. A dense fiber gasket can be trimmed to fit more easily than a metal-cored gasket.... but the critical concern is the positioning of the sealing beads on the gasket -- those are what does the sealing... the raised beads. IF they fall into the ports (due to a bad casting/core shift), then you will have a problem... get another/better manifold will be the solution.
IF your intake manifold does not have the center exhaust cross-over port (as many aftermarket aluminum manifolds are)... then you could still use the MS-90109... or else, use the Fel-Pro Performance intake set #1213. Those side rail gaskets are a dense fiber with Print-O-Seal sealing beads around each port; the dense fiber material is good for conformability as some aluminum manifolds have slight warpage and/or corrosion/pitting.
Regarding the search for the molded rubber f/r end seals, forget it... for small block Mopars... many years ago, I'm pretty sure that all gasket companies have already switched to the cork-rubber seals because of their better compression (up to ~50%)... whereby rubber is not compressible... it distorts upon being squeezed... and will commonly split apart beyond ~30% of squeezed. As an option, you could simply apply about 1/4" bead of RTV silicone (any kind, but black is suitable as it will resist the common temps at that location).
Finally, when you install the side rail gaskets, regardless of the F/R sealing you choose, be certain to apply a small dab of RTV silicone at that the 4-intersecting points of the manifold/head/ends.
Before installing the manifold, do yourself a favor and tap the head threading for the intake bolts, as well as run a cleaning die over each bolt thread -- you will be glad you did this (general practice for any assembly).
Here's a tip: On many SB Mopars, there may be front and rear metal dowels -- used to align the end seals as well as the intake manifold. However, sometimes the height of those dowels will cause the manifold to not come down enough upon being tightened, especially if there has been any resurfacing done to the block/heads or manifold. So... best if you just pull them out. Most aftermarket aluminum manifolds do NOT have the small hole F/R for the dowel... so again, best to remove the dowels.
Another tip: As for the plastic alignment dowels (as included in the MS-90109 set), depending on your manifold, it could be an advantage to grind a small relief area (tear-drop relief shape) into the manifold areas that the plastic dowels will be positioned (common 2nd form each end). I've seen OE cast iron manifolds with these reliefs, but never have I seen an aluminum (not the Eddy OE or aftermarket six-packs) having these tear-drop shaped reliefs. The slight raised height of the plastic dowels could, possibly, pending the manifold bolt hole diameter, hold up the manifold from being fully tightened down to the side rail gaskets. Most people are unaware of this matter when using the plastic alignment dowels with their intake manifold.... same scenario with the F/R metal dowel pins.
Final tip: On some aftermarket aluminum intake manifolds (regardless of engine brand), the intake ports may be slightly mis-aligned due to casting shift. The result is that the gasket may not seal properly around the ports... the raised sealing beads (either with a metal-cored gasket or the dense fiber gaskets) could fall uncompressed inside the ports -- not good! So, you have to visually inspect the alignment of the casting ports with the gasket ports. A dense fiber gasket can be trimmed to fit more easily than a metal-cored gasket.... but the critical concern is the positioning of the sealing beads on the gasket -- those are what does the sealing... the raised beads. IF they fall into the ports (due to a bad casting/core shift), then you will have a problem... get another/better manifold will be the solution.
Mopar Mitch
Well-Known Member
Kenny -- you can use the set #1213... but remember, there will not be any opened exhaust crossover port that matches the stock OE manifold, as well as the upper half-moon port to allow heat to evacuate from around that passage.
So, you'll have two decisions to make:
1. IF you want to keep the exhaust crossover port closed, then you'll need to lay a thin metal sheet cut for that port onto the gasket... use some very thin flat sheet metal. The metal will then prevent the center area of that gasket (#1213) from eventually burning through. Also, pending your carburetor and choke, you'll have to hook up either an electric or manual choke, or do away with it entirely.
2. IF you want to have the exhaust crossover ports open, then you'll need to scribe and cut the ports using a sharp knife (Exacto or similar)... to match the open manifold ports. Plan on spending at least 30 minutes to cut open the ports. The heat crossover allows the factory choke to remain in use as needed for cold startups.
One thing different with the Fel-Pro Performance intake sets, is that the cork-rubber end seals will have a peel-off adhesive backing to attach those end seals to the block (the MS90109 set's cork-rubber end seals do not have that adhesive backing).
Mitch i rarely use the car in the winter and the carb is a Edlebrock 650 electric choke. If i put them on as i got them they will eventually burn through right? Does it really matter since the car doesn't really get driven in the winter months
Mopar Mitch
Well-Known Member
Kenny -- I can't tell you how long it'll take for the material to burn through.. maybe 1-month or longer... pending how much you drive it... but it will eventually burn through. Play it safe and simply put a very thin metal shim at that area... you don't want the material clogging up your exhaust valves, either. The best material would be stainless steel for its higher temperature resistance vs common tin-plate, but the common tin-plate will do just fine. (Some Chevies use SS as the material for the crossover plate.)
Similar threads
