I need to replace the stock intake manifold on my 430. After much testing to find the cause of a serious vacuum leak, the issue has been narrowed down to the manifold. I'm currently running an Edelbrock Performer 1411 (750 cfm) carb and I'm planning on replacing the manifold with an Edelbrock Performer 2146. I'm also planning on blocking off the heat riser exhaust passages, using freeze plugs. Can anyone share their experience with installing and running an Edelbrock intake on a 430? Thanks, Danny '67 Riviera Austin, TX
I ran a 1"-4 hole spacer with mine and made a big difference in the feel at take off and on accel.If using a valley pan I coated the vacuum ports with copper spray and the end holes(water ports with a light beed of silicone.)Thats my preference.I had to drill out the head exhaust crossover holes deep enough to install my freeze plugs.If on the car cut a shop rag and stick down in there deep enough that you can still pull it out but the drill wont catch the rag(to stop the metal shavings from going into the exhaust chamber,then cover the intake valley and other intake ports,blow or vacuum the shavings out and install the freeze plugs)remember they must fit tight.)I coat them with locktite.Hope this helps some.
Get rid of the metal valley pan gasket and use composite gaskets, I like the silicone beaded ones that Poston and PAE use. Have JW install a permant tray on the bottom of your manifold or use the drop in AMP tray. 4-hole spacer as mentioned above is cheap horsepower, I run 5/8" thick.
Whats the deal with the Valley pan gasket? I run the stocker, and have had zero problems. In fact, with my exhaust crossover plugged, and that valley pan my intake is cold enough to touch, even when teh motor is at 180. The intake sealed fine every time, no problems.
Have always ran a Felpro valley pan on my B4B. Never had a problem with leakage or hot intake. I would not run without some sort of pan, even if you use composite gaskets and an insert pan. It keeps hot oil splash off of bottom of manifold. I use a Earick Racing Engines pan on my wifes 462 with TA composites and an SP1.
Thanks for all the information! Can anyone confirm if the Edelbrock Performer is the same height as the stock manifold? Also, I was under the impression from an recent post that 18mm freeze plugs would fit into the heat riser exhaust ports without any drilling. Is this not the case?
Before you go replacing the intake - have you tried replacing the valley pan gasket itself? There was a factory notice on this gasket, which had a tendency to develop a leak between the #6 and #8 (as I recall) intake ports, causing a loss of vacuum and a beyond-really-annoying squeal at speed. I personally have had this problem and am in the middle of changing said gasket offender out. Might save you a few C-notes anyway...
Aha! That could very well be my problem. Thanks for that tip Erik! I just double checked on the details of the work we did when the engine bay was refreshed in June. I wasn't involved throughout the entire process, so I wasn't sure on this one. The original valley pan gasket was re-used when the intake was re-installed (and the rubber gaskets were not used either - just a bead of RTV). I have a Fel-Pro intake kit with everything in it (it now comes with the valley pan, both rubber gaskets and one tube of black RTV). The instructions call for using the RTV on both intake and water ports. Hope this solves my problem and I can stick with my stock manifold! Either way, I now have enough info for both scenarios. I'll post an update.
Not bad mouthing valley pans in general, just the stock gasket/valley pan combo, hard to get a good seal especially if you've done some decking. Composite intake gaskets can be had in a range of thickness' and the fabricated aluminum pan options from a both TSP and AMP are a nice upgrade.
An old gasket should never be used over once it has been crushed. It will almost always leak.:bglasses:
I agree 100%. I couldn't be there for the entire process, unfortunately, so that was done without me (I would have gotten rid of the factory pan). I just found out this week that the original valley pan was re-used. I'm keeping my fingers crossed that this will solve my vacuum problem and that I can finally drive my car again!
I spent some time on the car today. Got everything disconnected and removed all 12 bolts holding the intake. It's not budging, however. Looks like it's being held on by the paint. I did find a bit of oil in my PVC valve, which probably means the valley pan isn't keeping the hot oil at the bottom of the valley. Is this a valid assumption? Anyone have a trick I could use to get the intake manifold loose?
I put a large screwdriver in to the thermostat housing(being careful not to damage the thermostat) and lift. It will come up. It's pretty heavy.
If Larry's screwdriver trink doesn't do it, take a pry bar and put it through one of the carb holes....it will pop loose....and no, it won't cause any damage.....unless you have forgotten to remove a bolt. OOPS!:spank:
If you want to get crazy, take the manifold to a machine shope and have it surfaced. It should be pretty cheap. YOu can get thicker intake gaskets to compensate. At the very least, check it for warpage.:Smarty:
Intake is now. I've attached some pics. I'm going to be bypassing the heat riser with 18mm freeze plugs. Looks like I'll need 2 per head, so 4 freeze plugs total. Is this correct?
