Exhaust Manifold Mod

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RustyRatRod

I was born on a Monday. Not last Monday.
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Don't know how many of yall are interested, but here's what I did. Well.......here's what my friend Freddie did. LOL Since I am a walking retard with a grinder, I asked my friend Freddie about enlarging a slant manifold outlet. He took it out to 2 1/4" with meat left over. He said he was sure it would go to 2 1/2" but we both agreed that it might be a little thin. At 2 1/4" it still has plenty left. He did a fantastic job going way into the outlet smoothing and enlarging the whole way. Here's the finished product along with an untouched original to compare to. I don't know what gains if any, but it can't hurt plus when I upgrade to the TTI slant six exhaust, it will be a better match.

MANIFOLD COMPARISON.jpg
ORIGINAL MANIFOLD.jpg
MODIFIED MANIFOLD.jpg
MODIFIED MANIFOLD1.jpg
 
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A couple more showing how far in he went with it. No, I don't think it can hurt at all. The plan is when I get the 225 built, I'll be pulling the 170 out of course and at that time I'll give the manifold back to Freddie so he can port match the manifold to the head, since the head for the 225 will be ported.

VIXEN MODIFIED MANIFOLD2.jpg
VIXEN MODIFIED MANIFOLD3.jpg
 
DOn't know how many of yall are interested, but here's what I did. Well.......here's what my friend Freddie did. LOL Since I am a walking retard with a grinder, I asked my friend Freddie about enlarging a slant manifold outlet. He took it out to 2 1/4" with meat left over. He said he was sure it would go to 2 1/2" but we both agreed that it might be a little thin. At 2 1/4" it still has plenty left. He did a fantastic job going way into the outlet smoothing and enlarging the whole way. Here's the finished product along with an untouched original to compare to. I don't know what gains if any, but it can't hurt plus when I upgrade to the TTI slant six exhaust, it will be a better match.

View attachment 1715546176 View attachment 1715546177 View attachment 1715546178 View attachment 1715546179
Freddie did a good job. Thanks for showing the pics.
 
oh man that is awesome... wish I woulda thought of that before bolting everything back on a few weeks ago... I'll have to file this under future projects. Thanks for sharing the info @RustyRatRod !
 
Maybe if I was able to afford to upgrade to the 32/36 Weber at the same time. As is, I don't know. As said, it caint hurt.
Looks good Rusty! Smart guy to know your limits. If you have a buddy that can do a nice job let him do it.
 
That should make a huge difference mated up with some free flowing exhaust. Slants like to breathe. My first car was a 72 dart with a slant. I threw on some 2.25 pipe and a glass pack and it was like night and day.
 
Old fashioned true old school hot rodding.....tip my hat to ya Rusty!!! Came out perfect..... been wanting to hog out of set of 273 manifolds ..
 
please update as to any gains, performance, etc..

ok, I'm updating. lol There is a definite change from about 2500 on up. No doubt. I think with the 2.5" exhaust, there will be even more added.
 
What about the knock off Weber? I had one on a 2.6 Mitsubishi for years with no issues. Actually still have it.
I accidentally ordered a Chinese weber and the quality was terrible. The butterflies rubbed on the throttle body and didn't open all the way. Sent back and got a real Weber.
 
I accidentally ordered a Chinese weber and the quality was terrible. The butterflies rubbed on the throttle body and didn't open all the way. Sent back and got a real Weber.
This has been probably 4 or 5 years ago and it didn't have any issues. Of course there's no quality control with those things, so maybe I just got lucky.
 
yup Ive done a couple of /6 exhaust manifolds the same way..... with another in the garage to "do it again" (think song by "Steely Dan")
I have never done anything to the ports on one, other than to clean up the hooks and sharp edges that would gouge my hands while handling.....
 
MoparMike1974, I do believe the Slant does like to breath. After I added the Super Six set-up on my ‘70 Dodge Slant6 I added a set of Hooker 3 into 1 headers into 2.25” real dual exhaust system with “H” pipe. Back to a pair of glass pack mufflers all the way to back of car capped with bright tips. Gives it a sound like a mild small block at Idle. Until you drive off then it does sound like a six.
 
I am super dupah with a grindah braddah as they say here. That being said- is it worth it just to buy a header on these things? I do kinda like the dual exhaust of the header look, but I am a complete newbie on sixes.
 
I am super dupah with a grindah braddah as they say here. That being said- is it worth it just to buy a header on these things? I do kinda like the dual exhaust of the header look, but I am a complete newbie on sixes.
Have you priced headers for a slantie yet?

If your ok spending that kind of dough, go for it

But if you were to calculate HP/dollar you'd get a much higher return on the DIY approach
 
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