Whats the TRUTH about MAC headers?......
Whats the TRUTH about MAC headers?...... I am loooking to buy MAC headers soon to free up a bunch of my horsepower that the cam should give me. I live in cali, so any headers except for shorties are illegal, but I will change the headers back to stock before I go in and get it smogged. I will have cats by the way and probably a cutout.
The reason I'm worried about LT headers is that they can be seen from just looking under thye car if a cop decides to pull me over and check. This isn't possible with MAC's. I have read somewhere that MAC's offer the same gains as LT's in the top end, but LT's had more power in the bottom end. Is this true? Recently, maybe people have been bad mouthing MAC's without any reason to back them up.
The set-up I am probably going to be getting soon is the MAC headers, with a 3" AAP y-pipe with CarSound cats welded in. Is there any problem with this? Thanks.
The reason I'm worried about LT headers is that they can be seen from just looking under thye car if a cop decides to pull me over and check. This isn't possible with MAC's. I have read somewhere that MAC's offer the same gains as LT's in the top end, but LT's had more power in the bottom end. Is this true? Recently, maybe people have been bad mouthing MAC's without any reason to back them up.
The set-up I am probably going to be getting soon is the MAC headers, with a 3" AAP y-pipe with CarSound cats welded in. Is there any problem with this? Thanks.
People who bad mouth Macs have not clue WTF their talking about....PERIOD...
I have installed probably 15 sets of Macs, and seen them dyno'd back to back vs. just about every Longtube out there. Macs will make the same peak RWHP as any 1 3/4 longtube on the market. LT's will more times than not, make slightly more low-midrange TQ (assuming we're referring to a 346 heads/cam engine)...
Port the primaries, and put a good collector on Macs, and they'll perform within 1 tenth/1 mph of a Longtube headers on a 346 ci heads/cam motor. I've seen it, i've done it, and don't repeat results I read about on the internet... PERIOD..
josh
I have installed probably 15 sets of Macs, and seen them dyno'd back to back vs. just about every Longtube out there. Macs will make the same peak RWHP as any 1 3/4 longtube on the market. LT's will more times than not, make slightly more low-midrange TQ (assuming we're referring to a 346 heads/cam engine)...
Port the primaries, and put a good collector on Macs, and they'll perform within 1 tenth/1 mph of a Longtube headers on a 346 ci heads/cam motor. I've seen it, i've done it, and don't repeat results I read about on the internet... PERIOD..
josh
Clearance is not a problem with MAC's on my lowered TA except going over speed bumps in a parking lot. I gained 14rwhp just with MAC's and the off-road Y-pipe. There are certainly more gains with long tubes, but as with every thing there are trade-offs. I bought MAC's because at the time they were the best bang for bucks headers including no fitment issues.
I do think the supplied Y pipe isn't that good so I had a Flowmaster Y collector welded in to help with flow and minimize the drone at 2400 rpms. I also "ported" or cleaned up the inside welds on the primaries. The HTS coating isn't that good, so I stripped the finish and sprayed on some Eastwood Hi-Temp header paint which has held up suprisingly well and will not flake or rust provided you applied it correctly. Installation is a plus with the headers dropping in from the top if you remove the coil packs and valve covers.
I do think the supplied Y pipe isn't that good so I had a Flowmaster Y collector welded in to help with flow and minimize the drone at 2400 rpms. I also "ported" or cleaned up the inside welds on the primaries. The HTS coating isn't that good, so I stripped the finish and sprayed on some Eastwood Hi-Temp header paint which has held up suprisingly well and will not flake or rust provided you applied it correctly. Installation is a plus with the headers dropping in from the top if you remove the coil packs and valve covers.
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Originally Posted by Mistacamawo
well ideally yeah but what if you need to make it look somewhat stock?
94106 for 2.5"
94109 for 3"
stay away from the mac cats.
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Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
Originally Posted by Mistacamawo
well ideally yeah but what if you need to make it look somewhat stock?
High flow cats don't cost *that* much power on stock internal cars, maybe 5rwhp/rwtq, but start messing around with H/C packages and you're leaving a noticeable amount of power on the table using them. Some H/C guys pick up 15-20rwph at peak and similar TQ (and gains across the whole rpm range) removing even high flow cats.
IMO, if you don't have to pass a sniffer (which many states don't have anymore for '96 and up cars, OBD scan only), then ditch the cats and ditch them quick.
PS. I can't imagine the hassle it must be for you cali guys having to put stock exhaust back on all the time for these tests. Can't you guys just slip someone some $$$$$?
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I have nothing to compare them too, but my Macs are completely problem free. No fitment problems, no banging, great price, etc....
I probably would have went with LTs if there was an inexpensive option available at the time (like hooker), but there was not. That said, I haev no intention of changing them now.
Tommy
I probably would have went with LTs if there was an inexpensive option available at the time (like hooker), but there was not. That said, I haev no intention of changing them now.
Tommy
If inexpensive long tubes were available when I bought my Macs, I probably would have gone with them. I have the ball flanges cut off, and a custom 3" y-pipe with a Flowmaster collector. Car runs good, times in sig. I see no reason to change the Macs, and I have a ton of ground clearance too.
Bruce
I see no reason to change the Macs, and I have a ton of ground clearance too.Bruce
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Joined: Nov 2001
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From: Texas
I have had the macs on my old setup and the car I have now. Install was easier than some folks claim, I dropped mine in from the top. Only thing I did different this time was hack the flange off and weld 3" exhaust straight to the header. Sounds good with true duals bullets and the hotcam chopping......
I've run MACs for about 2 years now, 1 year with their off-road y-pipe and the last year with a true dual setup and they work i guess. I dont have any dyno comparisons or anything like that but no complaints really. I am going to a LT setup now only because I got a killer deal on a set and I plan to stick with at true dual setup similar to the one I had with my MACs.
