New intake/exhaust manifold = PITA

[mo-mudder]

Got my new intake/exhaust manifolds from Alfa Heaven about a month ago for $165; not complaining about the price one bit. I am, howeber, complaining about the install. Good lord...
Inspection of manifold after hearing louder than normal exhaust noise revealed a totally broken off flange on exhaust #3. Some busted knuckles and greasy hands and 2 hours later, off came the 80# intake.exhaust/carb as 1 unit. Disassembly #1.
Got the box from Alfa and the new gaskets from car quest, and started bolting everything up. The alignment sleeves were a REAL pain. Got the carb on and fired it up, and there was some loud exhaust noise and a massive vacuum leak. Upon further instection, it looked like the #3 intake and #4 exhaust weren't making good seals. Using my trusty 2-AA maglight, I saw that the top of the two flanges were sealing, but there was about 1/8" gap on the bottom of both. Disassembly #2.
Thought I'd try using the whole set of new gaskets, and using 2 old gaskets on the #3 intake and #4 exhaust to try and seal the hole. Bolted everything up, and still had the loud exhaust + funky noises, and the massive vacuum leak. Thought about shaving off the upper portion of the #3 intake to get a good seal. Disassembly #3.
Then I had an idea. Not sure if it was a good one or a bad one, but an idea. I took the old intake and bolted it up to the new (to me) exhaust. Bolted it up, and still noticed a gap, but much less than was there before. Skipped the hour process of installing/disassembly/run test. Disassembly#4.
Tried a double gasket on just the #3 intake and #4 exhaust with the new exhaust and the old intake, installed the carb, and run test, and now it idles decently, and has manageable exhaust noise. Plumbed up an old flowmaster and some 2 1/4" exhaust pie and a tweeter cap and took it down the road and back for a 2 mile victory lap and ran like a champ. I think I even mighta hit 45. I'll snap a few pics tomorrow.

 

[gimpyrobb]

What a pain! The victory lap is just THAT much sweeter though.

 

[devilman96]

I hate to say this but that is prolly gonna crack again... and in the same place. Need to check the manifolds and head for warp'age... then have then shaved accordingly. Its a PITA process to under go but its better than buying another manifold set in a few months.

 

[mo-mudder]

I'm thinkin about fabricating an exhaust set from a sheet of 1/2" steel, and then some 16 or 20 ga. tubing to a collector to keep from dealing with the same cast iron problem as before. I figured this was just a way of buying some time before I had to go the custom-header route. I built a set for my mud truck and they work relatively well, so I'll probably end up doing that. Might even go with an different intake manifold, too, to keep from having everything bolted together.

 

[acetomatoco]

Did you put the sleeves in the exhaust ports on the head... they are separate from the gaskets? And secondly you assemble the manifolds loose to each other and then torque the parts to the head to spec.. so as not to bend or break the clamps and then you tighten the two halfs of the manifold together...and then retorque warm and cold a coupla times as the new gaskets compress.. just like doing a flat head jeep..minus the sleeves... ACE

 

[mo-mudder]

Yea, I did it a little different each time, placing the sleeves either in the head or the manifold, and the last time, right before I put everything together the way I wanted it, I put the 3 sleeves to the grinder and just smoothed out the rough edges on all sides of the sleeves. I'll make a note to let it warm up and shut it down and re-torque all the mounting bolts.

 

[hndrsonj]

Guarantee something is warped. Unless you fix it right it will be back.

 

[mo-mudder]

That's probably true. Might be the head, but if I'm gonna go thru the effort of removing the head and having it worked on, I'm just gonna jerk out the whole powerplant and tranny and repower it with a big block Ford. Might be the manifolds, but making one from steel might be a bit more elastic than the cast iron factory manifolds.

 

[11ACR-LT]

Ace is right about assembling it loosely and torqueing it up in stages, when I did my 211 I put a bead of hi-temp RTV on both sides of the gaskets at the intake ports and torqued it up, sealed up fine and been running 10 yrs,the alignment sleeves only go in the intake ports,don't over torque the bolts to seal small leakage between the exhaust manifold and head,this will not allow the manifold to "grow" as it warms up and will cause cracking and breakage. Hope this helps