ASM Large Runners Not Sealing
Thread Starter
Racer
Joined: Nov 2008
Posts: 321
Likes: 2
From: Auburndale FL
ASM Large Runners Not Sealing
Any one had problems with ASM runners not sealing? I had horrible vacuum leaks with with my new 383 so I finally took it to shop, he smoked the engine and found the ASM runners are not sealing.
He double checked my installation to make sure I didn't put wrong sides and confirmed my install was right but the runners just wouldn't seal. So he recommended going back to factory runners even though my throttle body is 58mm and plenum / base have been ported.
He tested fitment with OEM runners and they fit as expected so for the moment they are going on the car so I can get it running, I am curious how much impact overall the smaller runner diameter will have?
But worse I am out 500 bucks on runners that are collecting dust.
When I say they wouldn't seal I mean when installed you have to pinch the top together to get it to contact the plenum and then over tighten the bolts to try to keep it in place. Given the amount of space i don't see how using RTV would work so I am at a loss on this one.
Thanks and Beer Me!
He double checked my installation to make sure I didn't put wrong sides and confirmed my install was right but the runners just wouldn't seal. So he recommended going back to factory runners even though my throttle body is 58mm and plenum / base have been ported.
He tested fitment with OEM runners and they fit as expected so for the moment they are going on the car so I can get it running, I am curious how much impact overall the smaller runner diameter will have?
But worse I am out 500 bucks on runners that are collecting dust.
When I say they wouldn't seal I mean when installed you have to pinch the top together to get it to contact the plenum and then over tighten the bolts to try to keep it in place. Given the amount of space i don't see how using RTV would work so I am at a loss on this one.
Thanks and Beer Me!
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
When I put runners on I never tighten the bolts all the way down at first. The best way is to take the bolts up gradually and evenly, work your way from the center out the line of bolts, taking each up a small amount..This is one way to make sure you get sealing on every surface..You can't tighten the bottoms all the way up , and then tighten the tops , this can make them leak....WW
PS, Forgot to mention, the 383 will have way less power with the stock runners..The stock runners are restrictive even on the stock 350 motors...
PS, Forgot to mention, the 383 will have way less power with the stock runners..The stock runners are restrictive even on the stock 350 motors...
Last edited by WW7; May 23, 2013 at 08:10 AM.
Advanced
Joined: Nov 2002
Posts: 55
Likes: 0
From: Tulsa OK
I had a set of those chrome plated once and the chrome shop screwed them up by messing with the mounting surfaces..........had to buy another set.........very painful. They should seal just fine unless someone has messed with them. If not, send them back to ASM for repair/replacement.
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From: Merritt Ils Fl
Race Director
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From: Overland Park Kansas
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(Just checking to make sure we're talking about the same type of runner in this thread.)
Man, I bet locating a leak -- off the car -- would be tough. Off the car wouldn't be a picnic either!
Thread Starter
Racer
Joined: Nov 2008
Posts: 321
Likes: 2
From: Auburndale FL
Muffin,
Not sure about your's but with mine when we assemble the intake the tubes sit with a little less than 1/2 inch gap total gap between the plenum and tubes and that is with the base bolts loose. I pulled them together but ended up stripping a couple bolts, so the shop told me when they were working on it.
They replaced with factory tubes and everything sealed as you expect. I don't know if the tubes are warped, too short, or what the deal is. The shop told me they would probably work with an aftermarket intake but I really wanted to keep the factory stuff since it has been ported.
I am travelling next week on business so week after I will call AZM and see if I send them back if they can exchange or atleast check them out to see if there is a problem.
Not sure about your's but with mine when we assemble the intake the tubes sit with a little less than 1/2 inch gap total gap between the plenum and tubes and that is with the base bolts loose. I pulled them together but ended up stripping a couple bolts, so the shop told me when they were working on it.
They replaced with factory tubes and everything sealed as you expect. I don't know if the tubes are warped, too short, or what the deal is. The shop told me they would probably work with an aftermarket intake but I really wanted to keep the factory stuff since it has been ported.
I am travelling next week on business so week after I will call AZM and see if I send them back if they can exchange or atleast check them out to see if there is a problem.
Race Director
Joined: Jun 1999
Posts: 14,924
Likes: 9
From: Merritt Ils Fl
Gregg, I have picked up so much stuff from so many members I am not sure where, or who, they came from. On that note I spent so much time and effort trying to get them to seal when they came off the last time I threw them under the bench and moved on. The may well be Edelbrocks. I'll have to look.
My plan is to mount the heads and intake on the block finger tight/snug then the runners/plenum using a feeler gage to measure clerance as meral begins to touch metal. Stone/file a tad and try again. Way I figure the process will keep me out of trouble for a week or so.
My plan is to mount the heads and intake on the block finger tight/snug then the runners/plenum using a feeler gage to measure clerance as meral begins to touch metal. Stone/file a tad and try again. Way I figure the process will keep me out of trouble for a week or so.
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
Did you check the gaskets, I have had problems with the gaskets not lining up with runners and causing vacuum leaks, I solved the problem by filling in the leak with sealer when I installed the runners. The leak was at the top of the cold start injector location.
Pro
Joined: Oct 2008
Posts: 706
Likes: 265
From: Jyväskylä, FINLAND
I had a set of AS&M runners, which wouldn't seal properly. Tried them on several times with TPiS BigMouth intake manifold, then got fed up. Sold them to a friend, who finally got them to work with double gaskets, some machining and seriously overtightening all the bolts...
Then I got my hands on a set of Edelbrock's runners, which had to be welded some material on the lower end of the runners to match to the intake manifold. Also all the mating angles were off, so had to take them to a shop with plenum and intake manifold to make them fit.
There are some pictures, how poorly those Edelbrock runners fit in relationn with the plenum http://finnshark.com/forum/showpost....postcount=2108
First two pictures are with Edel runners and the two last pics with siamesed originals.
Then I got my hands on a set of Edelbrock's runners, which had to be welded some material on the lower end of the runners to match to the intake manifold. Also all the mating angles were off, so had to take them to a shop with plenum and intake manifold to make them fit.
There are some pictures, how poorly those Edelbrock runners fit in relationn with the plenum http://finnshark.com/forum/showpost....postcount=2108
First two pictures are with Edel runners and the two last pics with siamesed originals.