FLP's vs. MAC's...
 

In the spring, I will be doing a heads/cam/header/intake project. I am planning everything right now.

For headers, I am looking at both the FLP's and the MAC's. I live in a county in Ohio where the EPA is just as strict as The People's Republic of California so I absolutely have to have CATs.

My question -- Does anyone have any quantifiable data regarding the performance of FLP's vs. MAC's? For example, does anyone have a heads/cam car where you had MAC's, switched to FLP's and dynoed a significant difference.

Thanks in advance for the help.

Re: FLP's vs. MAC's...
 

There will be a difference in area under the curve. Peak numbers will not be that significant, and even the area under the curve will not be a dramatic difference on a mild head and cam job. My peak gains on my internally stock '99 with FLPs were +25 RWHP and +20 RWTQ (with cats), but there were areas of the graph where I gained as much as 35RWTQ.

Re: FLP's vs. MAC's...
 

Yeah there shouldn't be a hug difference but I say go with the FLP's.There more expensive but there a great header plus you can interchange the cats when you want too!! :D

Re: FLP's vs. MAC's...
 

I'll try to dig out my graph later. I went from macs to flps. Gained 0 rwhp over macs, but got about 20rwtq over the macs down low. An interesting thing was I found that the macs actually sounded better on my car than the FLPs did.

Re: FLP's vs. MAC's...
 

go with the thunderracing headers.

Re: FLP's vs. MAC's...
 

Thanks to all for the help.

Re: FLP's vs. MAC's...
 

I will warn you of one thing. If you deal with mac, BEWARE. Their customer service sucks! I spent 2 weeks trying to get them to respond to me. When they did, they admitted they hadn't included all my components in my order. Four weeks later, they won't respond to my emails or phone messages. Its hard to believe that a vendor can stay in business operating like this. I would go with a company with at least a resemblence of integrity. These guys suck.

Re: FLP's vs. MAC's...
 

I had absolutely no problem with MAC support. I was shy 4 bolts with my header kit and they had them here NEXT DAY!

As for Ohio Echeck, I think it'll be hit and miss. Depends on the inspector. One place waived my car off due to "tampering" since I have MACs. Another had no problem whatsoever. I guess I'll go through this all again here soon. I've heard the EPA is cracking down though and they are doing more checks for cats.