Bracket mods needed for Pro-Toplines?
Thread Starter
Racer
Joined: Jul 2001
Posts: 322
Likes: 1
From: Los Gatos, CA
Bracket mods needed for Pro-Toplines?
I have new pro-toplines on my 90 and have issues to solve with one of the brackets that mounts to the heads. The power steering bracket just needed to have holes enlarged to line up and is already done. The air conditioning and belt tensioner bracket is more difficult - One of the tapped holes holes in the head is missing altogether. Has anybody solved this one before?
One option is to add a tapped hole to the head (if it won't penetrate in a bad spot). Are there any others?
Thanks for the help
One option is to add a tapped hole to the head (if it won't penetrate in a bad spot). Are there any others?
Thanks for the help
Thread Starter
Racer
Joined: Jul 2001
Posts: 322
Likes: 1
From: Los Gatos, CA
Pro-toplines do not match the L98's exactly. I already knew about the power steering bracket issue so I was not worried. I made the wrong assumption that the other side was similiar with slightly changed hole locations. I did not know about the missing hole until it was too late. I had already built the new motor before I removed the old one...
I am wondering if someone else has run up against the same issue and how they solved it.
Thanks
I am wondering if someone else has run up against the same issue and how they solved it.
Thanks
Race Director
Joined: Aug 2000
Posts: 11,506
Likes: 4
From: Vancouver,Wa.
Originally Posted by 2manyfuncars
I have new pro-toplines on my 90 and have issues to solve with one of the brackets that mounts to the heads. The power steering bracket just needed to have holes enlarged to line up and is already done. The air conditioning and belt tensioner bracket is more difficult - One of the tapped holes holes in the head is missing altogether. Has anybody solved this one before?
One option is to add a tapped hole to the head (if it won't penetrate in a bad spot). Are there any others?
Thanks for the help
One option is to add a tapped hole to the head (if it won't penetrate in a bad spot). Are there any others?
Thanks for the help
You notice the other end of the head have three holes predrilled and tapped? I use to have the Protoplines on my car. 18 bad valve guides out of the box. Afr had 3.
Last edited by Corvette0096; Mar 25, 2005 at 12:05 PM.
Drifting
Joined: Aug 2001
Posts: 1,500
Likes: 0
From: Holliston MA
Cruise-In VII Veteran
I'm pretty sure that extra bolt hole is unique to L98 heads. I ran into the same problem when I installed my Canfield heads. I just drilled and tapped the extra hole using the bracket as a guide. Worse case is you'll need to use sealer on the bolt if you go into the water jacket. I also added a washer to the back side between the head and bracket so that I didn't mess up the pulley alignment or break the bracket. That bolt went into a raw casting area that was lower than the machined pads that the other bolts went into.
Racer
Joined: May 2004
Posts: 305
Likes: 9
From: Martell NE
Originally Posted by 2manyfuncars
Pro-toplines do not match the L98's exactly. I already knew about the power steering bracket issue so I was not worried. I made the wrong assumption that the other side was similiar with slightly changed hole locations. I did not know about the missing hole until it was too late. I had already built the new motor before I removed the old one...
I am wondering if someone else has run up against the same issue and how they solved it.
Thanks
I am wondering if someone else has run up against the same issue and how they solved it.
Thanks
Thread Starter
Racer
Joined: Jul 2001
Posts: 322
Likes: 1
From: Los Gatos, CA
Thanks for the replies. Drill and tap sounds reasonable to me.
I would not buy pro-toplines if I knew all of the issues they have. Flow wise they work pretty well and look to have well shaped combustion chambers, but I had a new valvejob done to correct widely varying stem heights. Dart or Brodix would have been a much better choice...
I would not buy pro-toplines if I knew all of the issues they have. Flow wise they work pretty well and look to have well shaped combustion chambers, but I had a new valvejob done to correct widely varying stem heights. Dart or Brodix would have been a much better choice...
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Burning Brakes
Joined: Jan 2002
Posts: 993
Likes: 4
From: Glen Burnie MD
Weird. All the accessory brackets lined up on my Pro Toplines, except for the alternator/PS one which had another bolt keeping it from lowering far enough. I was able to bend it, though.
However, I've had some other issues with my heads (as mentioned here recently) and would most likely never buy them again, or at least only buy 180's and have them ported bigger.
[RICHR]
However, I've had some other issues with my heads (as mentioned here recently) and would most likely never buy them again, or at least only buy 180's and have them ported bigger.
[RICHR]