Big thumbs up to MAC mid's
Big thumbs up to MAC mid's Help my buddy install a set of MACs on his 99 SS last night,and i just wanna say that I am very impressed with them.He got them off of ebay for i think just over $400 for the headers,y pipe,and hardware.They had a very nice silver finish on them,dont know if it was an option or not but they were gorgeous.The install took us about 6 hours to do from start to finish,mainly due to the fact that we could not for our lives get the driver side header up and in.ended up taking the coil packs off as a complete unit on the driver side to get the header up and then back down and in,and unbolted all the bolts on the pass side coil pack rail so we could swing it out of the way for a bit more room.also ended up cutting off that piece of the block on the pass side that gets in the way.luckily we read about that earlier before we started the project or else we woulda been ef'in clueless 
.
i almost cant wait to do them again now that i know what im doing.i think that me and the other 3 people that helped on the car could easily get a set installed in 4 hours,if not less.i already have a 98 Z28 that im going to end up doing them on,and as soon as i get my car ill definetely be getting some MACs.so we'll see.oh yeah and the exhaust system is a flowmaster american thunder,and it sounds SWEEEEEEEET.there isnt a single thing that sounds better than american muscle flowing through a flowmaster
.i almost cant wait to do them again now that i know what im doing.i think that me and the other 3 people that helped on the car could easily get a set installed in 4 hours,if not less.i already have a 98 Z28 that im going to end up doing them on,and as soon as i get my car ill definetely be getting some MACs.so we'll see.oh yeah and the exhaust system is a flowmaster american thunder,and it sounds SWEEEEEEEET.there isnt a single thing that sounds better than american muscle flowing through a flowmaster
Yes, MAC's are great headers and a breeze to install.
Oh, and Flowmaster is CRAP. It has the worst flow numbers of any cat-back system for our cars. Sounds great, yes, but you won't be seeing the full potential of the headers with Flowmaster (aka: Crapmaster, Chokemaster, etc...)
Oh, and Flowmaster is CRAP. It has the worst flow numbers of any cat-back system for our cars. Sounds great, yes, but you won't be seeing the full potential of the headers with Flowmaster (aka: Crapmaster, Chokemaster, etc...)
Originally Posted by Ferocity02
Yes, MAC's are great headers and a breeze to install.
Oh, and Flowmaster is CRAP. It has the worst flow numbers of any cat-back system for our cars. Sounds great, yes, but you won't be seeing the full potential of the headers with Flowmaster (aka: Crapmaster, Chokemaster, etc...)
Oh, and Flowmaster is CRAP. It has the worst flow numbers of any cat-back system for our cars. Sounds great, yes, but you won't be seeing the full potential of the headers with Flowmaster (aka: Crapmaster, Chokemaster, etc...)
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Joined: Apr 2002
Posts: 814
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From: Murrieta
The flowmaster thing has been proven again and again.
The Mac headers used to be a great bang-for-buck header. My heads and cam combo put down 447/409 through modded Macs (no ball flange) and a single 3.5" collector. I'd like to add that after upgrading to Jet-Hots and dual cutouts I gained 1.8mph. Never dyno'd it.
The Mac headers used to be a great bang-for-buck header. My heads and cam combo put down 447/409 through modded Macs (no ball flange) and a single 3.5" collector. I'd like to add that after upgrading to Jet-Hots and dual cutouts I gained 1.8mph. Never dyno'd it.
Just the crossflow design Flowmaster muffler is crap, which is the one for our cars. I had it, and yes it sounds great, but others sound better IMO. I have seen flow numbers for various cat-backs and IIRC, Flows was 300 CFM, while the Loudmouth was around 1600 CFM. Borla was like 800 CFM, I think... There are better exhausts than Flowmaster. If you are doing headers you are probably looking for SOME power gain, so I'm just saying Flows may be holding back the potential of your motor.
Originally Posted by MicahJam
The flowmaster thing has been proven again and again.
The Mac headers used to be a great bang-for-buck header. My heads and cam combo put down 447/409 through modded Macs (no ball flange) and a single 3.5" collector. I'd like to add that after upgrading to Jet-Hots and dual cutouts I gained 1.8mph. Never dyno'd it.
The Mac headers used to be a great bang-for-buck header. My heads and cam combo put down 447/409 through modded Macs (no ball flange) and a single 3.5" collector. I'd like to add that after upgrading to Jet-Hots and dual cutouts I gained 1.8mph. Never dyno'd it.
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Joined: Apr 2002
Posts: 814
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From: Murrieta
I never said all of my mph gain was from the headers, I simply stated the difference between the two setups. Here's the difference, make your own conclusions.
Heads/cam ~3800lb Camaro
, Macs, 3" ORY with a 3.5" flowmaster collector, open 3.5" cutout right after the Y. 118.2 mph
Same car, but with Jet-Hots and dual cut-outs: 120 mph
Heads/cam ~3800lb Camaro
, Macs, 3" ORY with a 3.5" flowmaster collector, open 3.5" cutout right after the Y. 118.2 mphSame car, but with Jet-Hots and dual cut-outs: 120 mph
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TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
Don't worry it makes sense but look at your Torque and HP curve and you'll find them different.
The gain of LT's increases as power adders go on but the Macs are great for street/strip set up. No clearance problems, no banging especially with lowered cars. It's like comparing oranges and mandarines, same species, different taste.
The gain of LT's increases as power adders go on but the Macs are great for street/strip set up. No clearance problems, no banging especially with lowered cars. It's like comparing oranges and mandarines, same species, different taste.
i had macs and i liked them,i don't think they are a bad set of headers at all. i just switched to kooks a pain in the azz to install,(driver side)but i'm trying to squeez every last drop of power from my car,and the kooks have a nicer sound too.
TECH Apprentice
Joined: Feb 2004
Posts: 341
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From: oklahoma city
I will be honest I have a flowmaster on my car, it sounds great over the stock muffler, that's why I got it. But I went to a Tenneco automotive class on Monday and they are the people who make Monroe shocks and struts and Walker and Dynomax exhaust systems among other products. They had a Dodge Truck that was on two ramps on the right side, we didn't know at first why the dodge had dual exhaust and one pipe coming out the right side, but that was when the instructor started to put on different mufflers on this pipe so we could hear them. Also had cutaways of all major types of mufflers and the Flowmaster had flow that is only like 150cfm over a generic turbo muffler, the dynomax was pushing almost 1000cfm nearly twice that of a stock muffler, and it was a straight shot from inlet to outlet. I was fairly impressed, But they didn't say anything about Magnaflow( which I most likely will be getting after my Jethots) But still wouldn't put their struts or shocks on my car, mom's car absolutley, mine no. Just some info, sorry so long
you bet ya can check out this thread 
https://ls1tech.com/forums/generation-iii-external-engine/157723-mac-headers-3-inch-x-pipe-pics.html
https://ls1tech.com/forums/generation-iii-external-engine/157723-mac-headers-3-inch-x-pipe-pics.html
TECH Fanatic
Joined: Jan 2002
Posts: 1,376
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From: Stuart Fl
The Macs are great. My car can vary up to 4 mph due to weather, so you cant compare the 118 to 120 unless the weather was pretty much ideal Also, how do you get a 3800# camaro? Convertible? My 00SS fully loaded with every option incl T-tops was 3450.It would take a 350# dude to make 3800!
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Joined: Apr 2002
Posts: 814
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From: Murrieta
Originally Posted by NastySSoo
how do you get a 3800# camaro? Convertible? My 00SS fully loaded with every option incl T-tops was 3450.It would take a 350# dude to make 3800!