Well this is my situation, I am going to put headers on my 95% street 1994 Z/28 this summer. I have narrowed it down to two types of midlenghts MAC and AS&M. But now I am stuck between the two for a number of reasons...

First: I am planning on doing at least a XE 224/230 cam package next summer if not P&P heads too. Will the Macs w/ 1 5/8" primary's restict this cam too much, even with the ORP in for racing?

Second: For the gains, is AS&M the better choice for this setup and worth $200 more? And if I get the AS&M would I need a new high-flow cat?

Third: I have a GMMG catback, which to my knowlegde is much too loud without a cat. If I get the AS&M setup is it worth $200 to get a Random Tech Cat? Or just use the stock or Cheap kind? Will the kind of cat make a difference? Or get the MAC and just use the ORP when I want to drop the cat?

So basically this is what I am looking at this:

1. Getting AS&M headers with a high-flow cat(if needed) ($750 + $250) = $1000

OR

2. Getting MAC headers and using the ORP occasionally But possibly choking my cam next summer.
($550 coated+ ORP $85) = $635

Are the gains worth $365??

If you understand my situation please make a comment, epsecially if you have this cam, headers or catback.
Thank you

-Dustin-

 

get the AS&M's, you'll kick yourself later if you get the smaller primaries. Headers is something you want to do once,


My exhaust setup is AS&M headers mated to a random tech ypipe with dual high flow cats into a flowmaster catback with welded on chrome stock tips. I love this setup, and the headers are excellent, coating still looks great after 2 years.

 

Acually, depending on your future plans with the car, I'd say the Mac's.

Why is that you ask when I myself have ASM's?? Simple:

The Macs are proven performers, cheaper, offer greatly better plug access. Granted the 1 5/8 primaries may be a little restrictive if you start going with a huge nitrous shot or a blower or turbo, but for a stock bottom end setup N/A they will most likely be fine. Ask 12SCNDZ, he just went 12.0 with them using heads and a CC305.

 

Yup...I like the MAC headers. Easy install, and great plug access. Like Fastbird93 stated. 12.0 with all the emissions BS still hooked up to them. Stock 95,000 mile bottom end, stock suspension, CC305, and full weight.
Wait till this year...LOL. I'm gonna put out an 11.8X "warning shot" with the new rear and a few other "goodies". Bottle passes should be somewhere in the 10.6-10.7 range.

The 12.0 was ran in 85% humidity

Frank

 

But will I see the full potential of the XE 224/230 with a 1 5/8 Mid? Pushing 350+ rwhp, it would always make me wonder... What kinda of gains are reported on each? I've heard .4-.5 tenths with the AS&M and 38-44rwhp and 28.4 rwhp and .3 gain with MACS.

Thanks for the opinions and comments, Keep em coming guys.

-Dustin-

 

The MAC's will be better at low RPM's and lose slightly at the higher RPM's to the AS&M's. Either way, you can't go wrong. The MAC's are better for daily driving due to the slightly better low end torque, but the AS&M's might get you a better time at the track due to better high end performance.

I am getting a very similar cam and I bought the MAC's because I will only be going to the track once in a great while. My car is a 50 miles per day daily driver and the MAC's with the better low end and better plug access where the headers for me.

I got mine directly from jet-hot for about $540 with the jet-hot coating.

Here's a picture

Dan

 

LOL..Hey Dan, I like my MACs, and my car sees the track ALOT Mine aren't near as pretty as yours, though. I wish I had went for the Jet Hot.

Frank

 

Yeah, with the times you are getting with the CC305 and MAC's, I guess I should say they are great for the street and the track.

I can't wait to get them on this spring. Then it's back to the track to see the performance increase.

Dan

 

Yes I know of the cam you are going to use (XE218/224), I read almost all the posts on Macs and AS&M, and I think you even debated both of them too. Yes those cams you guys are using are slightly smaller than what I plan to use. Thanks for the replies, I really appriciate it.

Anyone else got some input? I know someone else has MACS OR GMMG OR AS&M...

I like the AS&M but its going to bankrupt me, looks like the MACs are pulling ahead.

-Dustin-

 

You could also go for a Carsound high flow CAT instead of the Random Tech. That is what I bought. About $46 including shipping.

The MAC's come with the flange needed for one side of the CAT, all you need is a muffler shop with 3" pipe and the flange for the other side.

Dan

 

Yes I have thought about that too, I wonder how much of a difference $200 makes in a Converter? Would it gain anything in the 1/4? I cant think that it would... I am only getting a new cat if I go with AS&M, otherwise Ill just toss on the ORP on the MACs when the bears arent lookin

-Dustin-

 

AS@M ia an excellent header. RK Sport headers are the same identical header except it has some very minor differences. But it is 200 bucks cheaper.

The AS@M headers are more of a PITA for plug access, but do have 1 3/4 primaries.

I hit 109 mph with just AS@M headers, borla cat back and Moroso cold air sans cat converter. on a m-6 car.

Everyone I know with AS@M /RK Sport headers love them and they have also proven to make a ton of power, and results at the track.

 

Do you have a 1/4 time? And yes some of the reported gains are very appealing, I've seen 38-44 rwhp and .4-.5 off the 1/4 mile.

Thanks

-Dustin-

 

13.01 Had junk tires on it with w 2.0 60ft. 109 mph should have been good for 12.7s wit my street tires. I had bone stock susp. Other runs I hit 13.1-2's at 108 mph consistant..Best run was the 109 mph at 13.0

 

Do you live in an area where they do emissions testing?
If not why do midlengths? I would do LTs and be done with it forever.
Especially if you are doing heads and a cam. The LTs are the only way to go in my mind.

I am in a crappy situaution because I choose to do Pace Setters and now I want to switch to LTs...
I will be ordering Jet Hot LTs pretty soon