As with all headers The Flowtechs I installed on the 78 El Camino where a PITA, You might have two remove a few things like the oil filter and starter. You might have to raise the motor off the motor mount for one side.
Doug
Motor mount & Header choice
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Doug
Thanks for the warnings. The biggest pain I have endured installing headers was on a 69 Chevelle with a BBC. The headers had one tube on each side that wrapped around a frame rail. Impossible does not even get close to describing how difficult the installation was.
Okay. Think this is just about where I first came in on this subject. As matters currently stand, and after multiple exercises in research on the matter I think that I can safely say that there may be no manufacturer that makes a set of headers that are directly compatible with the clamshell style GM motor mounts. My own thread on this issue was Project Regress and it outlined exactly what I ran into. Both Hedman and Flowmaster, at some point in the last decade or so, modified their pipe design so that, instead of the number one tube coming straight out of the port, making a 90 degree turn towards the firewall, meeting 3,5, and 7, and then dropping down, they rotated it to come down at an angle to make that approach. What this means is that the number one tube crashes directly into the clamshell. Been there, had that happen. Tried to exchange a set of Flowmasters for a set of Hedman Elites and found that NONE of the Hedmans would fit. Hedman does not publish this fact on their own site but, during a visit to the OPGI site, I checked out a sale on headers that they were having, which was mostly Hedman products, and found, in the accompanying installation notes, a line that stated succinctly and directly that the clamshell mounts were not compatible with the product described above. This line repeated itself for all the headers that I investigated that would have otherwise been applicable for my G-Body M/Carlo, which, if memory serves, shares pretty much the same chassis as your 'Bu. The options that got discussed during my thread included changing out the complete mount assembly from the frame to the mill and substituting a race specific version that would accept the pipes, keeping the frame portion and exchanging the clam for a replacement offered by UMI that is made with the room to allow the pipe to pass; this was actually suggested by another Malibu owner on this site who had used them himself, or pulling the clams and modifying them to gain the room to let the pipe pass. One contributor to my thread actually stated that he had gone that route and done the work with the motor still bedded in.
What I have personally elected to do was take a spare set of the upper clams and modify them to a shape that, I think, will allow that number one pipe to move on by without issue. Right now they are in the paint booth and I had planned to take a pic or two of them tomorrow once they have dried. Once installed, I will be going back to my Flowmasters as I cannot exchange them; too many years since I bought them,. I can post copies of the pics of my version of those clams to this thread as well as attaching them to Project Regress. AS Interested?
What I have personally elected to do was take a spare set of the upper clams and modify them to a shape that, I think, will allow that number one pipe to move on by without issue. Right now they are in the paint booth and I had planned to take a pic or two of them tomorrow once they have dried. Once installed, I will be going back to my Flowmasters as I cannot exchange them; too many years since I bought them,. I can post copies of the pics of my version of those clams to this thread as well as attaching them to Project Regress. AS Interested?
I did have a set of Hedman's 68310 on my '81 with no issues with the clam shells. Outside of not reading the instructions at first, there was no real fit issues. I did have to reroute the battery cable from the original V6 routing. To add, these were one of the few sets that would work with the clutch linkage.
Yes, pics of the modified clam shells will be appreciated. I'm not opposed to buying motor mounts that will work. Part numbers/company name and any other details will help.
Thank you for your insight.
Further to my first comments, Pagrunt noted that he had run earlier versions of the Hedman's without encountering motor mount problems. In my 78 M/Carlo, when I swapped in the small block and lost the V-6, I ran Hedman headers from the get-go. Went through 3 or 4 sets of them due to winter driving but had no issues with them apart from the whole business of having to lift the car to do one side because it went in from below. Why Hedman changed its design is a mystery. Could be anything from better scavenging of exhaust fumes to money savings based on less tube being used or faster production. ??? Yeah, I will try to post those pics later on today.
Nick
Nick
If you are going to a solid mount Mororo's will give you more clearance, this is what I use for my BBC.
#62630 for the frame.
www.summitracing.com
And #62515 for the engine.
www.summitracing.com
#62630 for the frame.
Moroso 62630 Moroso Solid Steel Motor Mounts | Summit Racing
Free Shipping - Moroso Solid Steel Motor Mounts with qualifying orders of $99. Shop Motor Mounts and Inserts at Summit Racing.
www.summitracing.com
Moroso 62515 Moroso Solid Steel Motor Mounts | Summit Racing
Free Shipping - Moroso Solid Steel Motor Mounts with qualifying orders of $99. Shop Motor Mounts and Inserts at Summit Racing.
www.summitracing.com
As I offered earlier, here are the upper engine half clamshells that I modified to work with my Flowmasters. They would probably work with hedmans as well but I have no plans to create a test bed for clams and headers!!
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