MAC's are on!
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From: Farmingville, New York
MAC's are on! I posted a question about MAC vs. SLP headers a few days ago and went w/ the MAC's and the catted Y. Well, they are on and I couldn't be happier! The install went well w/o any major problems and the part I was really afraid of, the Y, fit beautifully! I have more ground clearance now than I did w/ the stock manifolds and cats. Well, maybe not more, but definately not less. They seemed to wake the car up a bit, but HP Tuners is showing that it's running pig rich, so I'm sure there's more in there! I'm going to E-Town on Saturday for the true test. I'll keep you all posted.
People really talk bad about these headers, but I dont know why.I had recently Installed Mac Mids with there catted Y Too.Woke up my car I am just having a fittment with driver header rubbing against steering colum u joint, but that problem is fixed now cause I installed urethane motor mounts to fix it.Maybe Today I will take it to the track.Here in south florida dont know if power is on for Moroso Motorsports Park.I think they are Good headers and flow as much as long tubes.
I bought my mac's from a guy in houston, and he made 540 rwhp with them on a mild cammed 422 motor. I made 375 rwhp with just a cam and macs and exhaust, and other small things. They are great, people hate on them saying go to LT's instead. LT's might give 5-10 rwhp max if that compared to these, especially if they have been worked on like mine have. Good choice. 
Originally Posted by RedRider81
.
Those are some sweet numbers. I also love my Mac's.
Those are some sweet numbers. I also love my Mac's.
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Well, just got back from E-Town and as happy as I am w/ the headers, definate SOP difference, the track was horrible. Traction was impossible. Best I could muster was a 12.64 @ 107 w/ a 1.9 60' and to top it off, I hurt the tranny. The 1-2 shift was real lazy and the 2-3 was slipping and bumping the limiter. . I tried 3 runs w/ the tranny slipping and ran 12.69, 12.67 and 12.64. I know that wasn't the smartest thing to do w/ the tranny slipping, but I was still able to make the 130 mile drive home. It never ends!
. I tried 3 runs w/ the tranny slipping and ran 12.69, 12.67 and 12.64. I know that wasn't the smartest thing to do w/ the tranny slipping, but I was still able to make the 130 mile drive home. It never ends! Trending Topics
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Originally Posted by fast01
I posted a question about MAC vs. SLP headers a few days ago and went w/ the MAC's and the catted Y. Well, they are on and I couldn't be happier! The install went well w/o any major problems and the part I was really afraid of, the Y, fit beautifully! I have more ground clearance now than I did w/ the stock manifolds and cats. Well, maybe not more, but definately not less. They seemed to wake the car up a bit, but HP Tuners is showing that it's running pig rich, so I'm sure there's more in there! I'm going to E-Town on Saturday for the true test. I'll keep you all posted.
I have the same system and I am realy happy with it. However, I realy think I lost some ground clearance with the cat on the driver side. Please see my photo. If yours is different (better), perhaps I can get an improvement on my system with a bit of fitting. I think it could be about 1/4" up higher, but then I would worry about it hitting the floor. Any ideas?
Thanks JA
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I'm at work right now, but I think my driver side cat is a little tighter to the floor. I'll take a look when I get home and see if I can get a picture up. It was just a matter of getting everything up into position and holding it in place w/ stands. I did have the benifit of using a lift, but I imagine you could do the same thing w/ jackstands and maybe some wood.
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Hi
Ya, the Kooks system is realy nice. It was just to pricy to import it into Canada for me. The stepped headers with cat Y pipe would have costed about 2k landed before the install.
Fast01: Hi I appreciate your help. No rush.
Thanks JA
Ya, the Kooks system is realy nice. It was just to pricy to import it into Canada for me. The stepped headers with cat Y pipe would have costed about 2k landed before the install.
Fast01: Hi I appreciate your help. No rush.
Thanks JA
Originally Posted by 3.8SFITURBO
MAC's are nice headers, Mine tick a bit and are uncoated so they look like shi* but they fit nice and sound good.
What makes the MAC's tick? I've read this before, but never heard an explanation.
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We put Mac's on my son's 94 Z28. They really woke up the car. I bought some used and ground the heck both at the ports and in the collector. The welding was not the best. I got them Jet Hot coated after grinding and they work great on his car. I went with long tubes on my 01, but I really doubt if they make any more power than the Macs. However, I've heard that the Mac Cats are very restrictive. So if you go with Macs, install your own high flow Cats.
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Hey JGA, I tried to post the picture I promised, but it keeps telling me my files are too large. Sorry man! I'm computer illiterate and don't know how to make them fit. 
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Originally Posted by fast01
Hey JGA, I tried to post the picture I promised, but it keeps telling me my files are too large. Sorry man! I'm computer illiterate and don't know how to make them fit.
I will assume you are using MS Windows. Open the photo in MS Photo Editor. You should be able to double click on the file and it should open in Photo Editor. Choose "Image" and then "Resize". You can make the photo smaller by adjusting the length and width dimensions.
There is a size limit when attaching the file so I think you have to get it under 100 KB or somthing like that. If you right click on the file and then select properties you should be abe to get the size of the file.
Thanks JA
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Originally Posted by glennhl
We put Mac's on my son's 94 Z28. They really woke up the car. I bought some used and ground the heck both at the ports and in the collector. The welding was not the best. I got them Jet Hot coated after grinding and they work great on his car. I went with long tubes on my 01, but I really doubt if they make any more power than the Macs. However, I've heard that the Mac Cats are very restrictive. So if you go with Macs, install your own high flow Cats.
I heard about the restrictive flow with the cats after I bought and installed my system. However, my system really woke up my car so they cannot be that bad. I think they have gotten a bit of a bum rap. Anyway, they are on now and I am in no hurry to replace them. Perhaps in a few years I will install higher flow cats.
Thanks JA
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Originally Posted by corvet786c
People really talk bad about these headers, but I dont know why.I had recently Installed Mac Mids with there catted Y Too.Woke up my car I am just having a fittment with driver header rubbing against steering colum u joint, but that problem is fixed now cause I installed urethane motor mounts to fix it.Maybe Today I will take it to the track.Here in south florida dont know if power is on for Moroso Motorsports Park.I think they are Good headers and flow as much as long tubes.
I live in Stuart. Do you know where we can get our cars tuned?
I havent heard of Macs in a while and when they were around during my header pick-time, they were not a bad buy. I do remember the cats being very bad, forgot where I saw the flow charts, but it was worse than the stock's. The chart had macs, stocks, carsound, random tech and maybe one more...anyone know where the **** that chart is?
Oh yea, do your macs have the HTS coating on it?