Redrig
Master Chief Petty Officer
- Joined
- Oct 13, 2009
- Messages
- 860
Hello all,
My 302 Manifolds have been getting worse and worse to the point that I am shocked my engine has not hydrolocked. So over the last year or so I have been putting the pieces together to do this conversion, I was able to piece this together for about half of what I have seen the "kits" go for.
I didnt want to just buy some old OEM ones just to deal with that same issue again. I thought I would go through the specifics to maybe help someone out , there is surprisingly little info out there on this .
old setup with the "logs" that have not been made in ages.
And here is the concept. Riser > 3" hose > elbow > 3.5 hose to intermediate.
The only thing that really suprised me is that the old manifolds are not fastened with bolts , they are held in with studs that have to be removed. So that took a little longer to get all of those out.
Finished
Fired it up and I had one leak on the starboard side, tightened the clamps up and no more leak.
Parts used.
GLM kit 58625 - That is the manifolds and risers only. 3 inch outlet I ckecked all the mating surfaces with a straight edge and they all looked good, nice and flat.
OSCO 803035 Elbow - you can buy just the elbow or a kit (CRR80x3.5) with the 3"hose and hose clamps, I used the kit, I believe there is a BARR elbow that will work too. Basically you need a 3" x 3.5" 90 degree elbow.
2 feet of 3.5 inch exhaust hose for the elbow to intermediate connection also Double clamp every connection
So thats what I used , I hope it helps someone, us old stringer guys need all the help we can get anyways. Like I said I pieced this together over time and have an all new exhaust for about 600 dollars, some of the conversion kits I have seen have been well above a grand.
Words of advice , when doing this do your valve cover gaskets while you are in there. Also I used hard wall exhaust on the elbow to intermediate connection , I am going to replace that with softwall (no wire) eventually, its a straight enough shot that there is no needs for the wired stuff and the fit could have been tighter.
My 302 Manifolds have been getting worse and worse to the point that I am shocked my engine has not hydrolocked. So over the last year or so I have been putting the pieces together to do this conversion, I was able to piece this together for about half of what I have seen the "kits" go for.
I didnt want to just buy some old OEM ones just to deal with that same issue again. I thought I would go through the specifics to maybe help someone out , there is surprisingly little info out there on this .
old setup with the "logs" that have not been made in ages.


And here is the concept. Riser > 3" hose > elbow > 3.5 hose to intermediate.

The only thing that really suprised me is that the old manifolds are not fastened with bolts , they are held in with studs that have to be removed. So that took a little longer to get all of those out.

Finished


Fired it up and I had one leak on the starboard side, tightened the clamps up and no more leak.
Parts used.
GLM kit 58625 - That is the manifolds and risers only. 3 inch outlet I ckecked all the mating surfaces with a straight edge and they all looked good, nice and flat.
OSCO 803035 Elbow - you can buy just the elbow or a kit (CRR80x3.5) with the 3"hose and hose clamps, I used the kit, I believe there is a BARR elbow that will work too. Basically you need a 3" x 3.5" 90 degree elbow.
2 feet of 3.5 inch exhaust hose for the elbow to intermediate connection also Double clamp every connection
So thats what I used , I hope it helps someone, us old stringer guys need all the help we can get anyways. Like I said I pieced this together over time and have an all new exhaust for about 600 dollars, some of the conversion kits I have seen have been well above a grand.
Words of advice , when doing this do your valve cover gaskets while you are in there. Also I used hard wall exhaust on the elbow to intermediate connection , I am going to replace that with softwall (no wire) eventually, its a straight enough shot that there is no needs for the wired stuff and the fit could have been tighter.
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