Icepick
Active member
Q, What headers do you use?
A, The headers I use are the 79-93 Mac mustang automatic version, I modify the collectors so that they fit the Gen 1 and work with the rest of the exhaust system that I make...
Q, Will these headers fit without modifications?
A, No! There is not a header out there that I know of that is made for a mustang that will fit a Gen 1 with a 351 and an E4OD transmission without modifications... The main problem is the width of the E4OD... I have tried "all" the Mac headers and the BBKs... The headers I use fit the best, require the least amount of modification plus there resonably priced for the quality and performance they offer... That is why I use them... As they come from Mac the passengers side header collector will hit the transmission bad enought to not allow the installer to get all the bolts into the head ports and forget about hooking up the mid pipe it's not going to happen... The drivers side fits no problem but the collector angle is less than ideal... I have spent a lot of time perfecting the modifcations that I make to the collectors and someone would be hard pressed to try to do a better job when it comes to fitment with the rest of the exhaust system in mind. Also the quility of work that I do on the headers could not be duplicated easily without the specific tools and fixtures that I use... If someone wants to buy a set of the Mac auto headers thinking they will fit or that the mods are so easy its not worth paying me to do I would be more than happy to sell the headers as they come and even offer advise on how to do it! I could also sell them cheaper than anyone else...
Q, If i already have a set of these headers can you modify them for me to fit a Lightning?
A, Yes, I charge $80. to do the necessary modifactions plus return shipping...
Q, Do you have to notch the frame rail and what does this entail?
A, Yes, The reason for the frame notch is because one of the primary tubes is to close to the top of the frame rail... If you undo the right motor mount nut and jack up the motor it is possable to fit the header in but once you let the motor back down the one tube will be very close or slightly hit the frame rail so when the motor shakes at idle or torques over under load due to the rubber motor mounts it will hit the frame... The frame notch is necessary to gain clearance in that area to prevent the tube from toching the frame... This frame notch is not a big deal! There is already an excisting notch in the frame for the stock header to clear... All you have to do is take it in about 1/2" deeper and 3" longer than the notch that is already there... My exhaust includes instruction with a picture that shows exactly what needs to be done... It takes about 2 minutes to cut the notch with a sawzall and a new blade... In the near future i will try to post a picture of this here so you all can see what needs to be done...
Q, Why do use these headers?
It is very simple... Price! Because of the huge mustang market and the manufacturing that is done in large numbers... This drives the price way down compared to making a very low production number header made specificly for the Gen 1... After my modifcations and the necessary frame notch they fit perfect! The only 1 5/8 & 1 3/4 long tube header that is specific to the gen 1 other than the ones I modify and sell is made by Kooks custom headers only sold through JDM enginering... They are very nice headers and fit without notching the frame but the cost is $800. which is twice the amount i sell the HTS coated 1 3/4 for... Plus they do not sell a full exhaust system to go with them so you would have to fabercate the rest of the exhaust or find someone to do it for you... Well, that's basicly it... If you can deal with notching the frame I can provide you with an exhaust that fits, looks and sounds great for a reasonable price... I have sold hundereds of these headers and exhaust systems now over the last 4 years and everyone seems very happy with them!
Q, What kind of performance do these headers offer?
They flat out make a lot of power! Most of the fast Gen 1 guys with a street/ strip type truck run my exhaust... Ed Huerta has run 12.4 @107 naturally aspirated and Jerry Skinner has run 9.4 @142 with a blower both are using my 1 3/4 headers and dual 3 " exhaust! There are many others running very well with my exhaust systems so the performance pretty much speaks for itself...
Q, Whats the differance between the 1 3/4 and the 1 5/8 headers and which should I use?
The only differance beteen the two is the tube size and price... As for which you should use depends on your combination and future plans... Either header will make a lot of power on a 351 based motor mild or modified and they both work very well... The 1 5/8 will produce more power and torque in the lower RPM range and the 1 3/4 will produce more up top... I suggest the 1 5/8 for stock or mild mods like heads cam, low boost superchargers etc.
The 1 3/4 are a better choice for built motors operating at higher RPM's, stroker motors, high boost superchargers, etc.
A, The headers I use are the 79-93 Mac mustang automatic version, I modify the collectors so that they fit the Gen 1 and work with the rest of the exhaust system that I make...
Q, Will these headers fit without modifications?
A, No! There is not a header out there that I know of that is made for a mustang that will fit a Gen 1 with a 351 and an E4OD transmission without modifications... The main problem is the width of the E4OD... I have tried "all" the Mac headers and the BBKs... The headers I use fit the best, require the least amount of modification plus there resonably priced for the quality and performance they offer... That is why I use them... As they come from Mac the passengers side header collector will hit the transmission bad enought to not allow the installer to get all the bolts into the head ports and forget about hooking up the mid pipe it's not going to happen... The drivers side fits no problem but the collector angle is less than ideal... I have spent a lot of time perfecting the modifcations that I make to the collectors and someone would be hard pressed to try to do a better job when it comes to fitment with the rest of the exhaust system in mind. Also the quility of work that I do on the headers could not be duplicated easily without the specific tools and fixtures that I use... If someone wants to buy a set of the Mac auto headers thinking they will fit or that the mods are so easy its not worth paying me to do I would be more than happy to sell the headers as they come and even offer advise on how to do it! I could also sell them cheaper than anyone else...
Q, If i already have a set of these headers can you modify them for me to fit a Lightning?
A, Yes, I charge $80. to do the necessary modifactions plus return shipping...
Q, Do you have to notch the frame rail and what does this entail?
A, Yes, The reason for the frame notch is because one of the primary tubes is to close to the top of the frame rail... If you undo the right motor mount nut and jack up the motor it is possable to fit the header in but once you let the motor back down the one tube will be very close or slightly hit the frame rail so when the motor shakes at idle or torques over under load due to the rubber motor mounts it will hit the frame... The frame notch is necessary to gain clearance in that area to prevent the tube from toching the frame... This frame notch is not a big deal! There is already an excisting notch in the frame for the stock header to clear... All you have to do is take it in about 1/2" deeper and 3" longer than the notch that is already there... My exhaust includes instruction with a picture that shows exactly what needs to be done... It takes about 2 minutes to cut the notch with a sawzall and a new blade... In the near future i will try to post a picture of this here so you all can see what needs to be done...
Q, Why do use these headers?
It is very simple... Price! Because of the huge mustang market and the manufacturing that is done in large numbers... This drives the price way down compared to making a very low production number header made specificly for the Gen 1... After my modifcations and the necessary frame notch they fit perfect! The only 1 5/8 & 1 3/4 long tube header that is specific to the gen 1 other than the ones I modify and sell is made by Kooks custom headers only sold through JDM enginering... They are very nice headers and fit without notching the frame but the cost is $800. which is twice the amount i sell the HTS coated 1 3/4 for... Plus they do not sell a full exhaust system to go with them so you would have to fabercate the rest of the exhaust or find someone to do it for you... Well, that's basicly it... If you can deal with notching the frame I can provide you with an exhaust that fits, looks and sounds great for a reasonable price... I have sold hundereds of these headers and exhaust systems now over the last 4 years and everyone seems very happy with them!
Q, What kind of performance do these headers offer?
They flat out make a lot of power! Most of the fast Gen 1 guys with a street/ strip type truck run my exhaust... Ed Huerta has run 12.4 @107 naturally aspirated and Jerry Skinner has run 9.4 @142 with a blower both are using my 1 3/4 headers and dual 3 " exhaust! There are many others running very well with my exhaust systems so the performance pretty much speaks for itself...
Q, Whats the differance between the 1 3/4 and the 1 5/8 headers and which should I use?
The only differance beteen the two is the tube size and price... As for which you should use depends on your combination and future plans... Either header will make a lot of power on a 351 based motor mild or modified and they both work very well... The 1 5/8 will produce more power and torque in the lower RPM range and the 1 3/4 will produce more up top... I suggest the 1 5/8 for stock or mild mods like heads cam, low boost superchargers etc.
The 1 3/4 are a better choice for built motors operating at higher RPM's, stroker motors, high boost superchargers, etc.
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