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76Fleetwood
06-13-2005, 10:46 AM
Hey Guys,

I’ve recently decided its time to do a little work on my 76’ Fleetwood brougham (engine has never been touched-68k mi) and one of the first things I want to get out of the way is the exhaust. The stock exhaust on there now is starting to rot away so making a new set of headers seems like the ideal way to go (especially seeing mts sells finished flanges). I talked to an old timer who used to race back in the day that works with a friend at a machine shop and asked him about header sizes for the cad. I mentioned the 1.75” flanges mts sells and showed him the specs I got out of the factory manual (cam, stock hp rating (210hp) etc) and he told me 1.75 is too big! And that I should go with a 1 5/8” somewhere around 35-45” long because of the low HP rating . Now if im correct, 1 5/8” is even smaller than the ports. Im afraid I underestimated the HP to him (just went by what I read) that even though itll help, it could be better.
Now everything is completely stock, and this car is a daily driver, but slowly being built up for the occasional “street race” with the mustang boys down the road. Basically whats planned for this engine..k&n filters, rejetting after the headers, and im working on building a sheet metal intake that’ll hopefully get a little more power out of it. Also I think ill drop in either the 5 or 10 grind mts cam.
Basically I just want to make sure 1-5/8” isn’t too small (its only .33” smaller flow area than 1.75”). Anyone have any recommendations if I should go with the 1-5/8” size or hop to 1.75”? also, if i went to 1.75, would the 40" or so length still work?

Thanks,
Blake

Al from MTS
06-13-2005, 02:17 PM
Your stock engine will love the 1 5/8 tube. Make them 42-45" long as well.
Our flanges are made to adapt common off the shelf headers to the Cad. The bulk of those headers are 1 3/4". So that's why we stock that size.

tommyhawk13
06-16-2005, 09:12 AM
1 5/8" is the only size primary I have ever heard of using in a Cad, modified or stock (except high rev).
Since you are making them yourself, have you considered making tri-y headers? I've heard that they make the best of both worlds, good low rpm torque & high flow for upper rpm.