Big Block side pipe header clearance issues.
Thread Starter
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
Big Block side pipe header clearance issues.
Man this thing is super tight against the steering box. Basically can barely slip a credit card thickness between the box and the header. Yes it’s an OE steering box.
I’ve put new mounts on both the motor and transmission and haven’t gained what I thought would be necessary. It has the factory shims under the mounts https://www.zip-corvette.com/66-74-4...ount-shim.html. It might gain some clearance if I slid the motor back but it’s pinned all the way back on the transmission crossmember slot as it is. Any suggestions...
I’ve put new mounts on both the motor and transmission and haven’t gained what I thought would be necessary. It has the factory shims under the mounts https://www.zip-corvette.com/66-74-4...ount-shim.html. It might gain some clearance if I slid the motor back but it’s pinned all the way back on the transmission crossmember slot as it is. Any suggestions...
Last edited by kossuth; Nov 1, 2019 at 07:52 AM.
Burning Brakes
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
Man this thing is super tight against the steering box. Basically can barely slip a credit card thickness between the box and the header. Yes it’s an OE steering box.
I’ve put new mounts on both the motor and transmission and haven’t gained what I thought would be necessary. It has the factory shims under the mounts https://www.zip-corvette.com/66-74-4...ount-shim.html. It might gain some clearance if I slid the motor back but it’s pinned all the way back on the transmission crossmember slot as it is. Any suggestions...
I’ve put new mounts on both the motor and transmission and haven’t gained what I thought would be necessary. It has the factory shims under the mounts https://www.zip-corvette.com/66-74-4...ount-shim.html. It might gain some clearance if I slid the motor back but it’s pinned all the way back on the transmission crossmember slot as it is. Any suggestions...
Safety Car
Joined: Sep 2005
Posts: 4,226
Likes: 643
From: Orange County Ca
I originally had used set of Hooker's , now Doug's when the Hookers rusted through. Both sets touched the steering box. As above, massage them to get some clearance. I worked a gigantic screw driver between the two to depress the pipe.
Burning Brakes
Joined: Dec 2003
Posts: 1,150
Likes: 154
It might be the motor mounts are different from one side to another,when I first pulled my engine I had about 1/8 to 3/16ths of an inch from the steering box to the headers,when I reinstalled the engine(I took the mounts out) I had no room at all.I pulled the engine again years later and put new motor mounts on and have about 1/16 of an inch.So try switching te mounts left to right before using a hammer.
Thread Starter
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
Any pictures pre and post handy work? These are coated headers. I REALLY DON'T want to take to massaging a set of new coated headers unless absolutely necessary. If thats the only way I will most likely return and get a set of non coated to modify.
Last edited by kossuth; Nov 1, 2019 at 08:32 PM.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I have Energy Suspension poly motor mounts. They cam with 1/4" plates to use between the block and the mounts. Raised everything just enough to clear.
Thread Starter
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
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Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
All I can say is the Energy motor mounts came with the 1/4" thick plates. I didn't use them on the first install and during warm up (big cam and rough idle) if I let the idle speed get to low the fan would contact the shroud, just enough to make some noise. Installed the plates and no more noise and the headers clear the steering box too.
Safety Car
Joined: Sep 2005
Posts: 4,226
Likes: 643
From: Orange County Ca
No pictures. I don't think I would dent coated headers either. Sounds like spacers may work. You'd have to watch hood clearance, fan shroud clearance, etc.